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Zheng, Jing. "Application of GAC adsorption in pulp and paper mill effluent treatment." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0019/MQ58522.pdf.
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Hedman, Jens. "Modelling of suspended solids effluent from a pulp and paper mill." Thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-171767.
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This study examines the wastewater treatment system on BillerudKorsnäs integrated pulpand paper mill at Karlsborg, with focus on the effluent of suspended solids. Due to lowerregulatory limits for the emissions of suspended solids BillerudKorsnäs is looking forways to improve the efficiency of the wastewater treatment. Therefore, this study seeksto create a statistical model for the emissions of suspended solids and to find which factorsin the production, wastewater treatment and surrounding environment that affects theemissions. The purpose of the study is to extend the current understanding of the treatmentsystem to create a base for future decisions. The methods used for the modelling areElastic net regression and Random forest classifier, which were selected for the variableselection properties they provide. Unfortunately, the results show that the fitted modelscan only explain a small part of the variation of the emissions of suspended solids.The lack of fit in the models indicate that the current data is not sufficient to explain thevariation in the emissions of suspended solids. During the study deficiencies in the datacollection has been detected and improvements to overcome these deficiencies are proposedin the hope of creating more reliable data for the company and to create a betterbasis for future studies.<br>Denna studie undersöker avloppsvattenreningen på BillerudKorsnäs integrerade massaoch pappersbruket i Karlsborg, med fokus på utsläppen av suspenderade ämnen. Pågrund ut av sänkta gränser för utsläppen av suspenderade ämnen undersöker BillerudKorsnäsmöjligheter för att öka effektiviteten i avloppsvattenreningen. Därför försöker dennastudie att skapa en statistisk modell för utsläppen av suspenderade ämnen och undersökavilka faktorer i produktion, avloppsvattenrening, och omgivande miljö som påverkar utsläppen.Syftet med studien är att förbättra förståelsen för avloppsvattenreningen och attskapa beslutsunderlag för framtida förbättringar. Metoderna som används i modellernaär Elastic net regression och Random forest classifier, vilka valdes för deras variabel selectionegenskaper. Resultaten för modellerna visar att modellerna endast kan förklara enliten del av variationen i utsläpp av suspenderade ämnen. Det dåliga resultatet indikeraratt nuvarande data inte är tillräckligt för att skapa den typ av modeller som används. Understudien så har brister i datainsamlingen upptäckts, och förbättringar för att överbryggadessa brister är föreslagna med ändamål att göra insamlad data mer pålitlig och skapa enbättre bas för framtida studier.
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Boissinot, Philippe. "Photooxidation of a TM pulp and paper mill effluent with hydrogen peroxide." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=24051.
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The photooxidation of a Thermo-Mechanical (TM) pulp and paper mill effluent with hydrogen peroxide $ rm(H sb2O sb2)$ was investigated at different experimental conditions by using a batch photochemical reactor operating at a dominant UV light wavelength of 253.7 nm. Photolysis of $ rm H sb2O sb2$ produces hydroxyl radicals ($ cdot$OH), which are very powerful oxidizing species. The effluent consisted of a "heat condensate" obtained from toxic vapors generated during various stages of the pulping process. Several operational parameters were varied and their effects on the process were observed and analyzed, in order to achieve its optimization. In addition, heterogeneous photocatalysts such as cupric oxide (CuO) were also investigated as a complement to the photooxidation process.<br>The main parameter used to determine the quality of the wastewater before and after photooxidation was the Chemical Oxygen Demand (COD), using a closed reflux standard procedure. COD values of the treated solution were determined at subsequent time intervals and used to draw curves illustrating the rate of oxidation of the wastewater. Other parameters, such as Dissolved Organic Carbon (DOC) and dissolved lignin concentration, were investigated towards the end of the research in order to obtain a more complete characterization of the quality of the wastewater after treatment.<br>The experimental data reveal that there is an optimal $ rm H sb2O sb2$ concentration that is best suited for the photooxidation of the effluent. Moreover, an increase in temperature accelerates the rate of elimination of COD. An increase in effluent concentration is detrimental to the speed of the process, since it causes an increase in its absorbance which can act as a barrier against UV light. The efficiency of the photooxidation process is not affected by variations in the initial pH of the wastewater. Cupric oxide (CuO), when exposed to UV light, efficiently catalyzes the production of OH radicals and is therefore very beneficial to the photooxidation process.
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Makris, Stephen P. (Stephen Paul). "Removal of resin and fatty acids from pulp mill wastewater streams." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5135.
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Resin and fatty acids (RFA) are predominantly components of coniferous trees having the natural function of protecting against microbial damage. These compounds are released from wood during the pulping process and a fraction reaches the wastewater treatment system. RFA are acutely toxic to aquatic organisms at concentrations on the order of parts per million, and their presence has been linked to toxicity outbreaks in receiving waters following process upsets. The chronic toxicity of resin and fatty acids in complex effluent matrices is poorly understood. Furthermore, the role of hydrophobic, pulp-derived solids as a removal pathway from wastewater streams has not been comprehensively studied. The objectives of this dissertation have been to quantify the relationship between resin and fatty acid concentration and chronic toxicity and to determine the role of partitioning in the removal of these compounds from pulp mill wastewater streams. Field and laboratory studies were conducted to measure toxicity using the Microtox™ whole effluent toxicity and Ceriodaphnia dubia 7-day, survival and reproduction bioassays. One resin acid in particular, dehydroabietic acid, was found to account for a significant fraction of final effluent chronic toxicity. Dissolved and sorbed RFA concentrations were quantified by solvent extraction, methyl ester derivatization, and GC-FID analysis. Partitioning to suspended solids was found to be a major removal pathway for the RFA from the effluent treatment system. A kinetic model for flotation was applied and compared to experimental data. Flotation was found to be effective at selectively removing RFA bound to pulp-derived solids from pulp mill and bleach plant sewers at moderate to high pH.
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Noggle, Jessica Joy. "Eastern mosquitofish as a bioindicator of pulp and paper mill effluents." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0009720.
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Thesis (Ph.D.)--University of Florida, 2005.<br>Typescript. Title from title page of source document. Document formatted into pages; contains 277 pages. Includes Vita. Includes bibliographical references.
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Morais, Ismarley Lage Horta. "Biological treatment of pulp and paper mill effluents with aerobic granular sludge." Universidade Federal de Viçosa, 2016. http://www.locus.ufv.br/handle/123456789/9372.
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Previous issue date: 2016-12-15<br>O tratamento de águas residuárias com lodo aeróbio granular apresenta muitas vantagens em comparação ao processo convencional de lodos ativados com lodo floculento. Os grânulos são agregados microbianos densos e compactos que possibilitam uma maior retenção de biomassa no reator biológico e uma elevada capacidade de sedimentação, favorecendo a remoção biológica de matéria orgânica, nutrientes, compostos tóxicos e clarificação final do efluente devido à estrutura e propriedade de sedimentação do lodo. Estes benefícios resultaram em um aumento do interesse de implantação do processo de tratamento com lodo aeróbio granular e a busca de maiores informações à respeito da formação, estabilidade e a influência dos parâmetros operacionais sobre a granulação. Assim, este trabalho apresenta uma revisão bibliográfica com a compilação das informações recentes sobre o lodo aeróbio granular incluindo a possibilidade de utilização dos grânulos aeróbios em biorreatores a membrana, em elevadas temperaturas e as aplicações em plantas de tratamento de larga escala. Foi realizada, ainda, a avaliação da adição de 100 mg.L-1 e 200mg.L-1 de cálcio na estabilidade, resistência mecânica e diâmetro dos grânulos formados em reatores em batelada sequencial alimentados com efluente de uma fábrica de polpa celulósica kraft. Os reatores apresentaram eficiências similares de remoção de matéria orgânica e o diâmetro médio dos grânulos foi de cerca de 11 mm em todos os reatores, embora os grânulos formados no reator que recebeu 100 mg.L-1 de Ca2+ apresentou velocidade de sedimentação 36% superior aos demais e maior resistência mecânica. A melhoria da granulação pode ser obtida ainda pela seleção de microrganismos que contribuem para a formação dos agregados. A produção de substâncias poliméricas extracelulares (SPE) pelas bactérias é um dos fatores que influencia a agregação celular, uma vez que as SPE agem como agente cimentante e atuam na adesão entre as células. A produção de SPE de dezenove isolados microbianos, obtidos de grânulos aeróbios formados no tratamento de efluente de fábrica de papel reciclado foi avaliada e seis isolados dos gêneros Staphylococcus, Agrobacterium, Enterobacter e Rhodococcus melhoraram a granulação biológica. A ausência destes isolados nos testes de co-agregação reduziu a relação entre proteínas e polissacarídeos (relação PN/PS) e diminuiu a formação de agregados.<br>Aerobic granular sludge wastewater treatment has many advantages over the conventional activated sludge process. The granules are dense and compact microbial aggregates that allow a higher biomass retention in the biological reactor and a high settling velocity, favoring the biological removal of organic matter, nutrients, toxic substances and improves wastewater clarification. Due to the sludge structure and settleability, these benefits have attracted considerable interest in the implementation of the aerobic granular sludge process and givenrise to the need for better understanding of the formation, stability and influence of the operational parameters on the granulation. Thus, this work was divided into three chapters. Chapter 1 presents a review of recent developments on aerobic granular sludge including the possibility of using aerobic granules in membrane bioreactors, at high temperatures and for a full-scale implementation. The addition of divalent cations in the reactors can enhance granulation and granule stability. In Chapter 2, the effect of the addition of 100 mg.L-1 and 200 mg.L- of calcium in the stability, mechanical strength and diameter of the granules formed in sequential batch reactors (SBR) fed with pulp mill effluent was evaluated. The reactors showed similar organic matter removal efficiencies and granule size was approximately 11 mm in all SBR, although the granules formed in the reactor with addition of 100 mg.L- of Ca2+ had a settling velocity 36% higher and greater mechanical resistance than the others. Granulation can also be enhanced by the selection of microorganisms that contribute to the aggregates formation. Bacterial extracellular polymeric substances (EPS) production is one factor that contributes to cell aggregation, since EPS acts as an intercellular cement that may reinforce cohesion inside the bacterial clusters. In Chapter 3, EPS production of nineteen microbial isolates obtained from aerobic granules formed in the recycled paper wastewater treatment was evaluated and six isolates of the genera Staphylococcus, Agrobacterium, Enterobacter and Rhodococcus contributed to biological granulation. The absence of these isolates in the co-aggregation tests reduced the protein-polysaccharide ratio (PN / PS ratio) and reduced the aggregates formation.
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Singh, Surendra. "The mechanism of fouling and synthetic membrane development for treating coating plant effluent from a pulp and paper mill." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0019/NQ46546.pdf.
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Bhathena, Jasmine. "The physical and physiological effects of nitrogen and phosphorus limitation on a pulp and paper mill effluent biotreatment microbial community /." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80228.
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The influence of nitrogen (N) and phosphorus (P) limitation on pulp and paper mill activated sludge (AS) floc properties was studied using a bioreactor fed with synthetic Kraft mill effluent. The bioreactor and synthetic effluent were designed and shown to perform like the real mill system providing the AS, establishing the in vivo relevance of the results. Limitation of either N or P produced inadequate effluent biotreatment, shown by poor BOD5 and suspended solids removal, and by decreased biomass health, performance, and floc settling. Greatly enhanced poly-beta-hydroxybutyrate (PHB) (but not carbohydrate or extracellular polymeric substances [EPS]) synthesis was the common response of the floc microbial community to N limitation over many days. In contrast, P-limitation increased total carbohydrate and EPS, but not PHB.<br>N limitation, but not P limitation, caused the net floc surface charge to be much more negative, while P-limitation, but not N-limitation, increased the floc bound water content and surface hydrophobicity. Thus, in real pulp and paper mill AS systems, careful manipulation of N or P additions may be useful to optimize the key process of charged polymer-assisted AS dewatering.
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Rodriguez-Chiang, Lourdes. "Enhancement of methane production from the anaerobic digestion of chemical pulp and paper mill effluents." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/669251.
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Sustainability of resources such as energy, water and waste have become important drivers in our current economy. For large industries that are water and energy intensive like pulp and paper (P&P) mills, this is a specifically relevant issue. The large and heterogenous volumes of effluents in P&P mills make it a difficult task to properly treat before discharge. Anaerobic digestion is an efficient wastewater technology that cleans the effluent, reduces wasted sludge and simultaneously produces methane that can be further used as energy. The research work described in this thesis aims to enhance the methane production from the anaerobic digestion of different chemical P&P mill effluents. Through effluent characterization, variability of process parameters, promoting agents and the assessment of biochemical methane potential (BMP) tests, the benefits of three potential methods to enhance methane yields of wastewaters were evaluated. In addition, the conversion of chemical pulp fibers directly to methane was explored. The attained results described the different improvements that can be made to enhance methane production.
Easily degradable effluents such as hydrolyzed filtrates and evaporator condensates contain high concentrations of sugars and acetic acid respectively, which could encourage an oversaturation of acids during acidogenesis. An inoculum to substrate ratio (ISR) of 2 proved to be the optimal in order to add the required buffering capacity to neutralize the pH and produce significantly high methane yields of up to 333 mLCH4/gVS. The high productivity of these effluents can be then considered for co-digestion with harder to treat effluents such as lignin-rich streams. Lignin clearly hinders methane production indicated by the negative linear correlation found between lignin content and methane yield. The co-digestion of lignin-rich effluent with evaporator condensates from neutral sulfite semi-chemical (NSSC) pulping proved to enhance the overall methane productivity of the mill´s wastewater treatment. Furthermore, the assessment of hydrotalcites (HT) addition indicated a contribution towards an increase in methane yield, faster production rates and a greater lignin removal. The poor performance of calcined HT suggests that the advantages of HT addition came from the layered sheet structure. Finally, besides establishing the methane potential in various P&P effluents, the examination of methane productivity of different pulp fibers and its products proved to be a promising new energy alternative to explore. Brown, oxygen delignified and bleached pulp gathered biodegradabilities of up to 90% and methane yields as high as 380 mLCH4/gVS. With the current changing bio-economy this last approach paves the way in exploring alternative and novel uses for chemical pulp mill products.<br>La sostenibilidad en la gestión de recursos como la energía, el agua y los residuos se ha convertido en un aspecto clave en nuestra economía actual. Para grandes industrias que consumen mucha agua y energía, como la industria de pulpa y papel (P&P) este es un tema especialmente relevante. Los grandes y heterogéneos volúmenes de efluentes que producen las fábricas de P&P hacen que su adecuado tratamiento sea una tarea difícil. La digestión anaerobia es una tecnología eficiente para el tratamiento de aguas residuales; que limpia el efluente, reduce el lodo producido y simultáneamente produce metano que puede usarse como fuente de energía. El objetivo del trabajo de investigación descrito en esta tesis es aumentar la producción de metano a partir de la digestión anaerobia de diferentes efluentes producidos en fábricas de pulpa. A través de la caracterización del efluente, determinación de parámetros del proceso, agentes promotores y la evaluación de pruebas de producción de metano bioquímico se evaluaron los beneficios de tres métodos potenciales para mejorar los rendimientos de metano de los efluentes. Asimismo, se exploró la conversión directa de fibras de pulpa química a metano. Los efluentes fácilmente degradables, como los filtrados hidrolizados y los condensados del evaporador, contienen altas concentraciones de azúcares y ácido acético, respectivamente, lo que podría provocar una sobresaturación de ácidos durante la acidogénesis. Se ha demostrado que una relación de inóculo a sustrato de 2 resulta óptima para aumentar la capacidad tampón del sistema y neutralizar el pH y producir rendimientos de metano significativamente altos, de hasta 333 mLCH4/gVS. La alta productividad de estos efluentes hace que se puedan considerar para la co-digestión con efluentes más difíciles de tratar, como las aguas ricas en lignina. Claramente la lignina obstaculiza la producción de metano, tal y como indica la correlación lineal negativa encontrada entre el contenido de lignina y el rendimiento de metano. La co-digestión del efluente rico en lignina con el condensado de evaporadores de pulpa semi-química de sulfito ha demostrado mejorar la productividad de metano en el tratamiento de aguas residuales de la planta. Además, la adición de hidrotalcitas (HT) como catatlizadores contribuye hacia un aumento en la producción de metano, tasas de producción más rápidas y una mayor eliminación de lignina. Con HT calcinadas se han obtenido rendimientos bajos, lo que sugiere que las ventajas de la adición de HT provienen de su estructura laminar. Finalmente, además de establecer el potencial de metano que existen en los efluentes de P&P, la evaluación de la productividad de metano de diferentes fibras de pulpa y sus productos ha demostrado ser una nueva alternativa energética para explorar. El uso de pulpa blanqueada, sin blanquear y deslignificada con oxígeno muestran biodegradabilidades de hasta 90% y rendimientos de metano de hasta 380 mLCH4/gVS. Con la cambiante bioeconomía actual, este último enfoque estimula la exploración de usos alternativos y novedosos para productos de plantas de pulpa química.
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Bacani, Vincent J. (Vincent Joseph). "Development of a rapid colourimetric assay for resin and fatty acids in pulp and paper mill effluents." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23253.
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Researchers have linked resin and fatty acids (RFAs) to acute toxicity, especially in thermomechanical and chemithermomechanical pulp and paper mill effluents. Thus, the measurement of total RFAs may be a rapid, inexpensive alternative to standard methods of toxicity monitoring, such as 96-hour rainbow trout testing. Current procedures for the analysis of RFAs typically involve solvent extraction and concentration, derivatization, and analysis by GC, HPLC, or TLC. These procedures are far too expensive, complicated, and time-consuming for implementation at mill sites.<br>This thesis reports the development of a rapid, colourimetric assay based on the dye methylene blue (MB) for the quantification of resin and fatty acids in pulp and paper mill effluents. This MB assay uses the complexation of the cationic organic dye molecule to the carboxylic acid groups of RFAs to form a measurable chromophore. The electrically neutral, blue-coloured complexes are then extracted into a poorly polar organic solvent, dichloromethane. The measured absorbance at 655 nm is directly related to the total RFA concentration in the effluent sample.<br>The methylene blue assay is inexpensive and simple to use. It has a method detection limit of 0.589 mg/L total RFA. There are good correlations between the results obtained using the methylene blue assay and a well-established GC assay, and between RFA concentrations measured by the MB assay and acute toxicity measured by Microtox. The assay is sufficiently simple and rapid to be practical for routine in-mill monitoring.
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Rava, Eleonora Maria Elizabeth. "Management of hydrogen sulphide generation at a Kraft paper mill." Diss., Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-09152008-113200/.
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Kommineni, Sunil. "Mechanistic study of ultrafiltration membrane fouling in the separation of molecular-size characterized pulp and paper mill effluents." Diss., The University of Arizona, 1999. http://hdl.handle.net/10150/284936.
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The use of ultrafiltration (UF) to treat pulp mill effluents is limited by fouling of membrane surfaces and pores. In prior studies with pulp mill effluents, no efforts were made to relate the molecular-size distribution of the solute molecules to the membrane fouling mechanisms. This dissertation presents a novel protocol for obtaining certain essential size distribution parameters, such as, the average molecular weight (M(w)), average molecular number (M(n)) and heterogeneity index (HI) to describe complex industrial wastewaters including the extraction (E)-stage effluent. This novel molecular sizing protocol was verified using challenge solutions containing solutes of known molecular weight. In these tests, the measured M(w)'s were within ±5% of the expected M(w)'s. A comprehensive model to describe the UF membrane productivity during the treatment of E-stage effluent was developed. This model accounts for variations in membrane, feed water and operational variables. The feed water variables that were incorporated into the model include molecular size distribution, viscosity and concentration. Also, included in the model are the operational variables such as trans-membrane pressure and cross-flow velocity. This model predicted the fluxes for the E- and oxygenated E-stage (E₀) effluents within an error of 9%. The UF membrane fouling by E-stage effluent was quantified employing fouling potential factors. An increase in the molecular weight cut-off (MWCO) of the membranes resulted in increased irreversible fouling possibly by increased pore plugging. Lower irreversible fouling was observed for pulp mill effluents with high M(w)'s. The role of surfactants in reducing the membrane fouling was also discussed. The ratio of M(w) of feed wastewater to the MWCO of the membrane, denoted by λ, effectively represents the ratio of the average diameter of the solute molecule to the nominal diameter of the pore. Membrane rejection and fouling potentials were related to λ. The measured apparent diffusion (D) and mass transfer (k) coefficients for the E- and E₀-stage effluents across the membranes were found to confirm to D ∼ M(w)⁻⁽⁰·³³ ᵗᵒ ⁰·⁴⁸⁾ and k ∼ D⁰·⁶⁶.
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Karat, Irma. "Advanced Oxidation Processes for removal of COD from pulp and paper mill effluents : A Technical, Economical and Environmental Evaluation." Thesis, KTH, Industriell ekologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121350.
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In Sweden, the dominating source for emissions of degradable organic substances to water is the pulp and paper industry. The organic substances increase oxygen consumption in the recipient which subsequently threatens aquatic species. Improved process engineering, process closures and use of external treatments have in recent years drastically lowered the Biological Oxygen Demand (BOD). However, the Chemical Oxygen Demand (COD) has not been reduced to the same extent, as some organic substances are more persistent and must be treated with more advanced techniques. Chemical precipitation, which can bind large parts of the remaining COD into solid matter, making it possible to be removed from the effluent by various separation technologies, contributes to an efficient COD removal. However, the direct operating cost for the treatment is high as large amount of chemicals are used in the process, and large quantities of sludge generated. In the near future EU pulp and paper industry will have to meet new regulatory demands on COD discharges, and pulp mills in Asia, South-America and Oceania will meet stringent discharge demands. It is therefore of interest to review alternative treatments in regards to technical, environmental and economical feasibility in the treatment of pulp and paper mill wastewaters. Much interest has been shown for Advanced Oxidation Processes (AOP), which is why these techniques have been evaluated in this thesis. The first part of the report consists of a literature review where processes with the following oxidants have been reviewed: 1. Ozone (O3); 2. Ozone + Hydrogen peroxide (O3/H2O2); 3. Fenton’s reagent (Fe2+/ H2O2); 4. Ozone + Ultraviolet light (O3/UV); 5. Hydrogen peroxide + Ultraviolet light (H2O2/UV); 6. Photo-Fenton’s reagent (Fe2+/ H2O2/UV); 7. Titanium dioxide + Ultraviolet light (TiO2/UV). Ozone treatment (1) and ozone in combination with hydrogen peroxide (2) were chosen for further experimental studies. The experiments were conducted at Wedecos (Xylem Water Solutions) laboratory in Germany and tested on wastewater from three different Swedish mills: A, B and C. The experimental results indicate that treatment with ozone is an efficient method for elimination of COD from pulp and paper mill wastewaters. A relatively high COD reduction (41 % for Mill A, 31% for Mill B and 53% for Mill C) was achieved for all wastewaters with an applied ozone dosage of 0.2g O3/L, without an appreciable impact on other parameters such as pH, N-tot, NO2-, NO3-, NH4+, P-tot and PO43-. There are indications that the nature of the wastewater has an impact on the COD removal efficiency and that TMP wastewater is easier to oxidize in comparison to wastewater from sulphate mills. The combination with hydrogen peroxide did not show any further COD reduction compared to ozone treatment alone, thus confirming the results Ko et al. showed in their study in 2009. Oxidation with ozone is seen as more environmental alternative in comparison to chemical treatment (precipitation/flocculation) because contaminants in the wastewater are destructed rather than concentrated or transferred into a different phase, which leads to the decrease of COD, colour and toxicity without the need to handle large amounts of sludge. However, a subsequent biological treatment may be necessary for removal of BOD as a BOD increase is registered for all wastewater treated in this study. The costs are on the other hand higher in comparison to chemical treatment even though there are indications of cases when treatment with ozone can be profitable (e.g. if the cost for sludge handling increases in the future, price for chemicals increases and electricity price decreases). There are some uncertainties regarding the system and there is no clear evidence that toxic by-products are not formed. More research must be done and more full-scale installations must be reported before the pulp and paper industry is willing to invest in oxidation technology.<br>I Sverige, är massa- och pappersindustrin den dominerande utsläppskällan av nedbrytbart organiskt material till vatten. När det organiska materialet når recipienten ökar syreförbrukningen eftersom stora mängder syre erfordras för nedbrytningen av materialet. Detta leder i sin tur till att de vattenlevande organismerna hotas och utsätts för syrebrist. Förbättrad processteknik, ökad processlutning och utbyggnad av extern avloppsvattenrening har under de senaste åren drastiskt sänkt den biokemiska syreförbrukningen (BOD). Däremot har den kemiska syreförbrukningen (COD) inte reducerats i samma utsträckning då delar av det organiska materialet är mer persistent och måste behandlas med mer avancerad teknik. Kemisk fällning kan idag binda stora delar av det kvarvarande COD till fast material som sedan kan avlägsnas via olika separationsmetoder. En stor nackdel med den här typen av rening är att stora mängder kemikalier används som i sin tur genererar stora mängder slam som måste tas om hand, vilket introducerar höga driftkostnader. Inom en snar framtid kommer massa- och pappersbruk inom EU att möta nya regulatoriska krav för COD utsläpp, och bruk i Asien, Sydamerika och Oceanien kommer även de att möta väldigt hårda utsläppskrav. Det är därför av intresse att granska alternativa reningsmetoder och utvärdera dess tekniska, miljömässiga och ekonomiska genomförbarhet vid behandling av avloppsvatten från massa- och pappersbruk. Mycket intresse har visats för Avancerade Oxidationsprocesser (AOP), varför dessa tekniker valts att utvärderas i detta examensarbete. Första delen av rapporten innefattar en litteraturstudie där processer med följande oxidanter studerats: 1. Ozon (O3); 2. Ozon + Väteperoxid (O3/H2O2); 3. Fenton’s reagens (Fe2+/ H2O2); 4. Ozon + Ultraviolett ljus (O3/UV); 5. Väteperoxid + Ultraviolett ljus (H2O2/UV); 6. Foto-Fenton’s reagens (Fe2+/ H2O2/UV); 7. Titaniumdioxid + Ultraviolett ljus (TiO2/UV). Utav dessa valdes ozon behandling (1) och ozon i kombination med väteperoxid (2) för vidare experimentella studier. Behandlingarna har utförts vid Wedecos (Xylem Water Solutions) laboratorium i Tyskland och undersökts på avloppsvatten från tre olika svenska bruk; A , B och C. Experimentella resultat tyder på att ozonering är effektiv behandlingsmetod för reducering av COD i avloppsvatten från massa- och pappersbruk. En relativt hög COD reducering (41% för bruk A, 31% för bruk B, och 53% för bruk C) uppvisades för samtliga avloppsvatten med en tillämpad ozondosering på 0.2 g O3/L, utan någon märkbar inverkan på andra parametrar så som pH, N-tot, NO2-, NO3-, NH4+, P-tot och PO43-. Det förekommer indikationer om att typ av avloppsvatten har en inverkan på COD reduktionen och att TMP avloppsvatten är lättare att oxidera i jämförelse mot avloppsvatten från sulfatmassabruk. Kombinationen av ozon och väteperoxid uppvisade ingen ytterligare COD reduktion i jämförelse mot ozon som enda oxidant, och bekräftade därmed de resultat Ko et al. uppvisade i sin studie 2009. Ozonering ses som ett miljövänligare alternativ till kemisk rening (fällning/flockning) eftersom föroreningarna i vattnet destrueras istället för att koncentreras, vilket innebär att COD, färg och toxicitet kan minskas utan att stora mängder slam genereras. Dock kan en efterföljande biologisk behandling vara nödvändig för avskiljning av BOD då en BOD ökning uppvisats för samtliga avloppsvatten i denna studie i takt med att COD brutits ned till lättnedbrytbart biologisk material. Kostnaderna är däremot höga i jämförelse mot kemisk fällning även om det förekommer indikationer på fall när behandlingen kan vara lönsam (t ex om slamhanteringskostnaderna blir högre i framtiden, inköpspriset för kemikalier ökar och elpriset sjunker). Det råder vissa tveksamheter gällande systemet och det finns inga konkreta bevis på att toxiska biprodukter inte bildas. Mer forskning måste utföras och fler fullskaliga installationer måste rapporteras och innan massa- och pappersindustrin är villig att investera i oxidationstekniken.
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Long, Xiaoping. "Minimum effluent process for pulp mill." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/11825.
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Watkins, E. James. "Foulant adsorption onto ion exchange membranes." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/7062.
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Melanson, Jason B. "Effluent recycling in a Kraft pulp mill." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0009/MQ60153.pdf.
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Moreira, Leandro de Jesus. "Minimização de efluentes em uma fábrica de polpa kraft lo-solids® branqueada de eucalipto." Universidade Federal de Viçosa, 2010. http://locus.ufv.br/handle/123456789/5903.
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Previous issue date: 2010-07-09<br>Historically, the pulp and paper industry has been one of the largest consumers of natural resources. The volume of water consumed in the sector reaches an average value of about 25 to 100 m3 per ton of pulp produced. Among the stages that comprise the kraft process, the bleaching plant is the largest source of liquid effluent generation. Reducing effluent generation, through partial or total system closure, significantly reduces fresh water consumption and brings benefits in terms of reduction of environmental pollution. The purpose of this work was to evaluate the feasibility of reducing fresh water consumption in the bleaching system, through the recirculation of bleaching filtrates. From the current conditions of pulp process of Lwarcel Celulose Ltda, which has total effluent generation of 22 m3/adt, two degrees of closure were analyzed, generation 19,5 and 17,5 m3/tsa. Based on these conditions, the final product quality, concentration and influence of non-process elements (NPEs) in the circuit, reagent consumption on bleaching and concentration of effluent generation were analyzed. Results indicate that as the circuit was closed, the concentration of non-process elements (NPEs) was increased in the system and only one alternative analyzed meets pulp quality requirements.<br>Historicamente a indústria de celulose e papel tem sido considerada uma das maiores consumidoras de recursos naturais. O volume de água consumido pelo setor alcança em média valores de 25 a 100 m3 por tonelada de polpa celulósica produzida. Dentre os estágios que compõem o processo kraft, a planta de branqueamento constitui a maior fonte de geração de efluentes líquidos. Impactos significativos através da redução de geração de efluentes, com fechamento parcial ou total do circuito, trazem economia no consumo de água fresca e benefícios ambientais. A proposta deste trabalho é avaliar a viabilidade da redução do consumo de água fresca no processo de branqueamento, através da recirculação de filtrado no circuito. A partir das condições atuais do processo de fabricação de celulose da indústria Lwarcel Celulose Ltda, que apresenta geração total de efluente de 22 m3/tsa, analisou-se dois graus de fechamento, geração de 19,5 e 17,5 m3/tsa. Com base nestas condições verificou-se a qualidade do produto final, concentração e influencia dos ENPs no circuito, consumo dos insumos de branqueamento e concentração do efluente gerado. Os resultados obtidos apontam que à medida que o circuito de águas foi fechado, aumentou-se a concentração dos elementos não processáveis no sistema e que apenas uma das alternativas avaliadas satisfaz os requisitos de qualidade.
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Young, Stephanie. "Pulp mill effluent induced coagulation and flocculation in receiving waters." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ60362.pdf.
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Fraser, Donald Scott. "Fate and effects of pulp mill effluent solids in the soil environment." The University of Waikato, 2007. http://hdl.handle.net/10289/2621.
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The pulp and paper industry in New Zealand annually produces over one hundred thousand dry tonnes of solid waste due to the treatment of pulp and paper mill effluents, the majority of which is currently landfilled. The New Zealand Waste Management Strategy (2002) has set a target for the diversion of commercial organic wastes from landfill to beneficial use to exceed 95% by 2010 . Effluents produced by softwood pulp mills, such as in New Zealand, contain high concentrations of naturally derived resin extractive compounds that are toxic to fish and other aquatic organisms. Improvements in waste water treatment technology has enabled the industry to meet rigorous discharge standards, however, this has resulted in an increase in the production of pulp mill effluent solids which require disposal. This has become an issue for the pulp and paper industry, especially as current landfill space is limited. Land application has been used for many years as a means of disposal of pulp mill wastes. While most studies investigating land application of pulp mill effluent solids have concluded that the risk posed to the environment is low, few have investigated the potential toxicity of these wastes to soil organisms, and these studies did not directly address the effects of resin extractive compounds. Resin extractives have been shown to be recalcitrant and to accumulate in anaerobic sediments. It is not known to what extent resin extractives are bioavailable or degradable in land applied Pulp mill effluent solids (PMES), or their potential to bioaccumulate in soil organisms. This PhD thesis research sought to extend the knowledge on the environmental fate and effects of pulp mill effluent wastes. It focused on terrestrial systems, which have not been well studied in this respect. Four chemically distinct softwood pulp mill effluent solids, a primary treatment solid and three secondary treatment biosolids, were used to investigate their effects on soil organisms and soil functions. An interdisciplinary approach was adopted, which incorporated three main areas of study, as follows: 1. A comprehensive resin extractives analysis of the pulp mill effluent solids undertaken so that effects on soil organisms and soil functions could be related to the resin extractives chemistry of the individual pulp mill effluent solids tested. 2. A battery of bioassays used to investigate the toxicity of the selected pulp mill effluent solids. 3. A field trial set-up to investigate how pulp mill effluent solids affected soil functions and also to investigate the decomposition of pulp mill effluent solids and of resin extractives in these solids. Three hypotheses tested were: I. Pulp mill effluent solids are toxic to soil organisms. II. Resin extractives in pulp mill effluent solids are recalcitrant in the terrestrial environment. III. Pulp mill effluent solids will cause significant measurable negative impacts on soil functional capacity. A wide range of resin extractives compounds were identified in pulp mill effluent solids, and concentrations of individual compounds varied widely between the different pulp mill effluent solids tested. During the two years after field application of the pulp mill effluent solids, resin extractives declined, however, decay rates of individual compounds were variable. The decay rate of compounds was influenced by the type of pulp mill effluent solids containing these compounds and not by the initial concentration of compounds. All compounds, including resin acids, degraded rapidly in the applied primary solid and in one of the applied biosolids, with average half-lives calculated ranging from three to twelve months. In the other biosolids, resin acids were recalcitrant with average half-lives calculated to be nearly ten years. Laboratory bioassays conducted on oats, earthworms and enchytraeid worms indicated that pulp mill effluent solids had low toxicity to these organisms. An aquatic bioassay organism, however, was acutely affected by aqueous extracts from pulp mill effluent solids. Earthworms were shown to bioaccumulate some resin extractive compounds to a limited extent, indicating that resin extractives were bioavailable in pulp mill effluent solids. Enchytraeid reproduction was reduced by exposure to some pulp mill effluent solids but this was not correlated to resin extractives concentration of the solids tested. Field applied pulp mill effluent solids significantly enhanced the fluxes of CO2 from the soil surface. When mass losses of pulp mill effluent solids carbon were taken into account, it was shown that these solids had little effect on soil respiration. Needle litterbags were placed above and below pulp mill effluent solids and in the litter horizon of a control treatment for 12 months. Needle litter decomposition was not significantly different between treatments, however, changes in enzyme activities were detected in litter beneath pulp mill effluent solids compared to control needle litter that had not been exposed to pulp mill effluent solids. The decomposition rate of field applied pulp mill effluent solids was slow, with half-lives extrapolated to be between five and twenty five years. The decomposition rate appeared to be influenced by the pools of carbon available for decomposition, with primary solids decaying significantly faster than biosolids due to a higher cellulose component. The conclusions of the PhD thesis research are, therefore, that generally, pulp mill effluent solids used in the study were demonstrated to be relatively benign and appear to pose a low risk to the terrestrial ecosystem when applied to soil. However, a cautious approach is still recommended to land application, based on the extensive evidence of disruption to aquatic ecosystems, and because pulp mill effluent solids will take many years to decompose and resin acids are recalcitrant in some pulp mill effluent solids. Further research is recommended to elucidate mechanisms of action by resin extractives in soil organisms and the ultimate fate of these compounds in the soil compartment.
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Coakley, Jonathan Davis. "The role of bleaching in pulp mill effluent effects on fish." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ37941.pdf.
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Jones, John B. "Towards zero liquid effluent at a complex fine paper mill." Thesis, University of Manchester, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616898.
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The paper industry traditionally used water on a profligate scale. In recent decades the industry has responded to increasingly stringent environmental demands by various measures, one of the most cost-effective of which has been to reduce water consumption and consequential discharge. In fact, it has now become received wisdom among paper makers that reduced water consumption and reduced environmental impact go hand in hand. Reflecting this belief, regulatory authorities have increased the pressure upon the paper industry to reduce water discharges. Operation with Zero Liquid Effluent is now widely accepted as being best for the environment. The research reported in this thesis demonstrates that in mills making fine papers, this is not necessarily the case. In such mills, the minimal environment impact may well result from operating with a small, but non-zero, discharge of water, purified before final discharge to a watercourse. The reason lies in the nature of operation in fine paper mills. In such mills, grade changes take place very frequently, often several times each day on each machine. Each grade of fine paper is made from a furnish comprising a unique combination of raw materials, including special chemicals, dyes, and fillers. A portion of these materials fails to be retained during sheet forming. This portion remains in the backwater, in dissolved or suspended form, and is ultimately returned to the forming section. Backwater from one grade of paper cannot be used for another grade, because doing so would result in off-grade paper. During grade changes, therefore, the papermakers purge contaminants from the backwater system, by dumping contaminated backwater and by making off-grade paper, which must also be dumped. Both strategies result in brief shock loads on the environmental protection system.
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Nyberg, Thomas. "Process steam : Steam conditioning at a pulp and paper mill." Thesis, Karlstad University, Division for Engineering Sciences, Physics and Mathematics, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-582.
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<p>Abstract</p><p>This report is the result of an examination work at the University of Karlstad. The purpose of this project is to examine how the condition of the steam affects the efficiency of the steam consumers and how variations in that condition affect a pulp and paper mill.</p><p>This report is meant to describe the main components regarding steam production, steam conditioning and steam consumption. It should also be able to give basic information about the significance of steam conditioning in the pulp and paper industry. It is aimed to people working with steam conditioning to increase their understanding and knowledge about it.</p><p>The aim of this report is to:</p><p>• Describe the function of the most commonly used steam generators and the difference between these.</p><p>• Identify the main steam consumers and describe their function.</p><p>• Give an introduction to steam conditioning and its role at a pulp and paper mill.</p><p>This report will try to answer the following questions:</p><p>• How does the generated power from back-pressure steam turbines vary with grade of superheat of outlet steam?</p><p>• What are the advantages with steam conditioning?</p><p>• Are the steam conditioners at Gruvöns bruk able to deliver steam at the right condition?</p><p>The conclusions from this report are that;</p><p>• If the steam conditioning valves are able to reduce small steam flows to the correct temperature, more power can be produced. The design condition of the steam turbines can than be nearer saturation.</p><p>• The temperature variations are more critical at the turbine inlet than downstream the steam conditioning valves. The valves at Gruvöns bruk who are studied in this report, are fully functioning.</p><p>• Common for the main steam consumers at pulp- and paper mills are that they are all sensitive for variations of steam temperature, especially high temperature.</p>
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Jortama, P. (Pirjo). "Implementation of a novel pigment recovery process for a paper mill." Doctoral thesis, University of Oulu, 2003. http://urn.fi/urn:isbn:9514272226.
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Abstract
The objective of this study is to demonstrate an ecological and economic recovery process, which was developed and implemented at Stora Enso Oyj Fine Paper Oulu mill during the period 2000 to 2002. The ECO plant recovers the material called ECO pigment from the effluent treatment sludge and it can be used as a filler in multicoated fine paper production for art printing purposes.
The ECO plant process consists of the following process stages. First, there is a separating phase for the recoverable material from fibres and other rejects, which is done with a wire washer. Then the fractionating of the recoverable material is performed with two-stage centrifugal cleaners. Chemical treatment with peracetic acid is used as a preservative and to increase the brightness of the ECO pigment a little. Then the recoverable material is stored in the pigment storage area and dosed to the paper machines as a filler. The rejects from the ECO plant are thickened in belt filter presses and then transferred to the bark storage area, where they are mixed with bark and combusted in a solid fuel boiler.
The majority of the particles of the recovered ECO pigment were less than 45 μm; this size of particle accounted for 96.4% (on average) according to the studies made between June and December 2002.
The use of ECO pigment is not found to cause more web defect problems on the base paper than before, according to the studies of the number of total web defects with the achieved particle size distribution and because the microbe content has been controlled.
There are three sources from which the ash content of the base paper is composed after the start-up of the ECO plant, i.e. the broke, the virgin filler and ECO pigment. Therefore the use of ECO pigment partly decreases the need to use virgin filler. The ECO pigment was tested in the coating colour in pilot tests, and based on these results it could be used in the coating colour. The dry solid content of the ECO pigment has to be increased from the present level for the coating application.
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Fortin, Nathalie. "Molecular characterization of dechlorination potential in kraft pulp mill effluent treatment systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0002/MQ29692.pdf.
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Fortin, Nathalie. "Molecular characterization of dechlorination potential in kraft pulp mill effluent treatment systems." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27317.
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Many low molecular weight chlorinated organic compounds produced by the pulp and paper industry during kraft bleaching of the wood pulp are toxic. Mass balance studies suggest that mineralization of chlorinated organics is occurring in pulp and paper mill wastewater treatment systems. To understand the nature of dechlorination activity, molecular tools such as oligonucleotide primers and corresponding DNA probes were developed to monitor the presence of microorganisms possessing key genes (dehalogenases) responsible for the degradation of chloroaliphatic organics in kraft pulp mill effluent treatment systems. Oligonucleotide primers designed from the coding sequence of known dehalogenases and a methane monooxygenase gene, which is known to catalyze dehalogenation reactions, were used for polymerase chain reaction (PCR) analysis, using genomic DNA extracted from dehalogenating bacterial isolates and total community DNA extracted from water and sediments of lagoon treatment systems. PCR amplification with dhlB oligonucleotide primers, designed from the haloacid dehalogenase of Xanthobacter autotrophicus, revealed the presence of dehalogenase genes in both aerated lagoons and stabilization basins. Similar results were obtained with mmoX primers designed from the methane monooxygenase gene of Methylococcus capsulatus. DNA sequence analysis of several PCR fragments showed significant similarity to known dehalogenase genes. The molecular tools developed in this study revealed the presence of different types of microorganisms with dechlorination potential in the microbial community of pulp mill effluents.
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Smits, Judit Emmy Geraldine. "Biological effects of dietary bleached kraft pulp mill effluent on mink (Mustela vison)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq24017.pdf.
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Joyce, Stephanie Anne. "Biological factors affecting pulp mill effluent-induced coagulation and flocculation in receiving waters." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0015/MQ47047.pdf.
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Carter, Shane Basil. "Adsorption of Colour from Pulp and Paper Mill Wastewaters onto Diatomaceous Earths." The University of Waikato, 2007. http://hdl.handle.net/10289/2400.
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Abstract Production of pulp and paper from raw wood involves the washing of substantial quantities of highly coloured material from the wood pulp. Although most of this colour is trapped within the mill and the mills wastewater treatment system, discharge of coloured wastewater remains a problem of public concern. Lake Rotorua, New Zealand is filled with sediment consisting almost exclusively of diatoms. The most abundant species, Aulacoseira, has been shown to have very small pores, less than 200 nm, that could be very useful for the capture and holding of large organic molecules. Lake Rotorua is situated close to the two largest pulp and paper mills in New Zealand and may have to be dredged to solve a problem of eutrophication. Wastewaters generated at the Kinleith (Tokoroa) and Tasman (Kawerau) mills in the North island of New Zealand have been used to assess the characteristics of colour removal by Lake Rotorua diatoms. Vacuum filtration through the diatoms succeeded in removing colour but proved to be impractically slow as an industrial process. Addition of diatoms to wastewater streams in stirred experiments showed that significant adsorption took place. The majority of the colour was removed within 30 seconds of mixing. The efficiency of colour removal was found to vary between wastewater streams within the mills. The pH dependency of this removal was tested and found to be most effective in a pH range of 3.6 to 5. Attempts to reuse the diatoms showed that chemical backwash regimes were more effective than calcination. This study concluded that surface silanols were likely to be the principle agent in forming coagulants with the colour material and were subsequently trapped on the diatom surfaces, but more importantly within the pores.
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Renner, Victoria Emily. "Sources and ecology of Escherichia coli in pulp and paper mill biosolids." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27549.
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Pulp and paper mills generate biosolids as a by-product of their effluent treatment systems. These biosolids show excellent potential as a soil conditioner. However, the detection of high levels of E. coli (10 2 to 105 CFU/gdw), in the absence of any significant fecal loading, has caused concern among effluent treatment system operators, land applicators and regulators. This research examines the sources and ecology of E. coli strains comprising the population of E. coli in the biosolids of an eastern Ontario pulp and paper mill by applying the molecular microbial source-tracking tool repetitive sequence-based polymerase chain reaction. Confirmed E. coli were successfully isolated from 2 forested sites, treated mill process feed water, storm effluent, mill fibres, wood chips, primary and secondary clarifier effluents and sludges, and biosolids. While laboratory isolates could be accurately distinguished from forest and industrial isolates, cluster and jackknife analyses were incapable of differentiating reliably among isolates from the forest, on-site inputs, effluent treatment system and biosolids (average rates of correct classification values ranged from 43.9% to 72.9%). No input could be excluded as a source of E. coli to the effluent treatment system. Many fingerprint types were unique to the primary and secondary clarifiers; however, only a subset of the fingerprint types recovered from the primary and secondary clarifiers were detected in the biosolids. This suggests that the E. coli strains found in mill biosolids were those able to survive the hot, desiccating conditions of dewatering. Highly similar fingerprint types (> 80% similarity) were recovered repeatedly over an 8-month period from the effluent treatment system (primary and secondary clarifiers) and biosolids. These results are consistent with growth within the effluent treatment system and biosolids, rather than fecal loading. Over a 3-year period the pulp and paper mill effluent treatment system underwent large-scale changes, including a 50% reduction in effluent volume upon the elimination of on-site pulping activities. New fingerprint types were detected in the biosolids following the restructuring, and the Shannon index of diversity increased. Disruption of established operating conditions could have opened niches, allowing new strains to colonize the mill effluent treatment system successfully.
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Mao, Huazhong. "Development and evaluation of the ozone/immobilized fungal process for pulp mill effluent treatment." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22155.pdf.
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Söderholm, Kristina, and Ann-Kristin Bergquist. "Growing Green and Competitive : A Case Study of a Swedish Pulp Mill." Umeå universitet, Institutionen för geografi och ekonomisk historia, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-68930.
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The experiences of past efforts of industrial pollution control while maintaining competitiveness should be of great value to research and policy practice addressing sustainability issues today. In this article, we analyze the environmental adaptation of the Swedish pulp industry during the period 1970–1990 as illustrated by the sulfite pulp producer Domsjö mill. We investigate how this company managed to adapt to heavy transformation pressure from increasing international competition in combination with strict national environmental regulations during the 1960s to the early 1990s. In line with the so-called Porter hypothesis, the company was able to coordinate the problems that were environmental in nature with activities aiming at production efficiency goals and the development of new products. Swedish environmental agencies and legislation facilitated this ―win-win‖ situation by a flexible but still challenging regulatory approach towards the company. From the early 1990s and onwards, the greening of the pulp industry was also a result of increased market pressure for green paper products.
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Downing, Gavin. "The effect of changes in bleached kraft pulp mill effluent on plasma cortisol of fish /." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68170.
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In a three year study, the applicability of the cortisol response to capture as a biomarker of the health of fish from areas chronically exposed to pollution was assessed. Northern pike (Esox lucius) and yellow perch (Perca flavescens) captured from an area contaminated by bleached kraft pulp mill effluent (BKME) were initially found to be incapable of elevating their blood cortisol concentration to reference levels. Following a reduction of the amount of absorbable organochlorines (AOX) in the BKME, fish downstream of the mill regained their normal cortisol response to capture. The time frame for this recovery was from between 6 to 18 months. Fewer young fish downstream of the effluent provided evidence for the impact of long-term exposure to BKME at the population level.<br>The impairment of the cortisol response to capture, and its subsequent recovery after effluent reduction provide the foundation for developing cortisol as a biomarker of contaminant exposure. Further work should determine the relationship between cortisol and the effect at higher levels of biological organization (e.g., population and community).
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Latva-Somppi, Jouko. "Experimental studies on pulp and paper mill sludge ash behavior in fluidized bed combustors /." Espoo : Technical Research Centre of Finland, 1998. http://www.vtt.fi/inf/pdf/publications/1998/P336.pdf.
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Leiviskä, T. (Tiina). "Coagulation and size fractionation studies on pulp and paper mill process and wastewater streams." Doctoral thesis, University of Oulu, 2010. http://urn.fi/urn:isbn:9789514260889.
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Abstract
This thesis aims to increase our knowledge about the characteristics of chemical pulp process and wastewaters and how problematic substances, e.g. wood extractives, could be removed effectively and selectively by coagulation–flocculation with either internal or external water treatment. Characterization was performed by investigating kraft pulp bleaching filtrates, as well as wastewater, before (influent) and after (effluent) the activated sludge treatment by means of a range of chemical analyses and by carrying out size fractionation studies. Cationic polyelectrolytes were used to purify oxygen stage bleaching filtrate, and charge analyses (zeta potential, charge quantity) were carried out in order to understand the coagulation phenomenon. In activated sludge treatment, the enhancement of particle removal, either by filtration or using a chemical in the primary clarifier, would lead to savings in aeration costs and result in a more stable process. Microfiltration already with a large pore size (8 µm) removed 30–50% of the wood extractives from the influent. Separate treatment stages for certain wastewater fractions, e.g. debarking plant effluent, would ensure cost-efficiency. After the activated sludge process, the wood extractives were present as particles (18%) and < 3 kDa fraction (82%). β-sitosterol occurred only in particles in the effluent. The release of harmful components into the environment could be decreased by microfiltration (e.g. 0.45 µm) of the final effluent or using a chemical in the secondary clarifier. Interestingly a huge increase in BOD was realized in the 3 kDa fraction of both influent and effluent, which indicated the presence of toxic substances in the larger fractions. After passing the effluent into the water system, there might be a similar jump in the BOD because the effluent is diluted many-fold. This would contribute to the formation of areas with an oxygen deficit. In the coagulation–flocculation studies, effective and selective removal of wood extractives (92%) from the oxygen stage filtrate was obtained with a cationic polyelectrolyte of medium molecular weight and medium charge density at 72 °C and pH 5–6. The multimodal zeta potential distribution gave more information than the average zeta potential. Aggregation of colloidal particles occurred when only one zeta potential was observed. The number of different zeta potentials diminished with decreasing pH and after exceeding a certain polyelectrolyte dosage level.
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Mower, Barry F. "Effects of Pulp and Paper Mill Discharges on Fish Populations in Three Maine Rivers." Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/MowerBF2009.pdf.
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Kemppainen, Hanne. "Mapping of causations for edospore formation and process optimization at pulp-and paper mill." Thesis, KTH, Skolan för bioteknologi (BIO), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-150698.
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BillerudKorsnäs is a manufacturer of fiber-based cartonboard and liquid packaging board. Microbial growth occurs at several steps in cartonboard production due to favourable environment and the good access to nutrients from the raw material, and additives such as starch. Vegetative bacteria are usually not harmful in the production and die in the hot drying end of the cartonboard machine. The most abundant microflora at paper- and cartonboard factories consists largely of sporeforming microorganisms from the genera Bacillus and Paenibacillus. The endospores are highly resistant and can stay in the final end product, which is undesirable. Levels of endospores from these species at BillerudKorsnäs production unit KM5 are usually low, but an occational increase can be seen when a new cartonboard product, KW1 is produced. Today, the method used for controlling the microbiology is by adding biocides to broke towers. This has shown to be both expensive and non-effective at KM5. A new method is needed for controlling the microbiology at KM5 that is more effective, costbeneficial and environmental friendly.The aim of this project was to test a hypothesis for spore formation at a paper board factory in lab-scale experiments. A suggestion of a technical change in the process would be made that could minimize spore formation and the use of biocides at KM5. A model organism Bacillus licheniformis (E-022052) was used to study effects of environmental conditions on spore formation. Experiments were also performed in controlled bioreactor trials, where methods to minimize spore formation were tested.The experiments showed that nutrient deficiency of a primary carbon source was the major reason for spore formation and should be avoided at KM5. Further, the experiments showed that oxygen limitation significantly decreases the endospore formation.The conclusion reached, was that spore formation could be minimized by a feed addition of glucose to Broke tower 1 during the few days production of KW1. A second alternative includes using a feed of concentrated pulp that could be used to minimize spore formation without the use of biocides and without the need for rebuilding of the mill.
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Sehlberg, Jimmy. "Steam Prediction at an Integrated Pulp and Paper Mill : Mondi Dynäs in Kramfors Municipality." Thesis, Luleå tekniska universitet, Energivetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79636.
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The most important energy carrier at an integrated pulp and paper mill is steam, it is essential to power components and machinery. The components create variations in the steam grid network, variations that exceed the capacity of the steam accumulator. To avoid steam shortages, production leans towards having the accumulator nearly filled, eventually leading to periods with over production. Abundantly produced steam must be released from the steam grid network, and this is done without energy recovery. The purpose has therefore been to create a computer model with the ability to predict steam consumption for the entire mill. The prediction shall eventually be used in the control systems for steam producers and the accumulator. By knowing future steam demand, production can be planned more efficiently and so can the accumulation level of steam. This will allow a greater range of operation since the predictor can provide information on when significant steam demand changes will occur. The most important energy carrier at an integrated pulp and paper mill is steam, it is essential to power components and machinery. The components create variations in the steam grid network, variations that exceed the capacity of the steam accumulator. To avoid steam shortages, production leans towards having the accumulator nearly filled, eventually leading to periods with over production. Abundantly produced steam must be released from the steam grid network, and this is done without energy recovery. The purpose has therefore been to create a computer model with the ability to predict steam consumption for the entire mill. The prediction shall eventually be used in the control systems for steam producers and the accumulator. By knowing future steam demand, production can be planned more efficiently and so can the accumulation level of steam. This will allow a greater range of operation since the predictor can provide information on when significant steam demand changes will occur.By creating separate predictor models for the largest steam consumers, the final predictor consists of four minor predictor models. The first is related to five batch digesters, the second to one of the two paper machines (PM5), the third to the other paper machine (PM6), finally the forth to all other consumers. The separate predictors have been created by gathering historical process data connected to their operation. Analyses and correlations have been made to show what has significant effects on their steam consumption. The final predictor has shown the possibility of having an R2 above 0.7 for up to one hour ahead. Even though, it is possible to have 60 minutes of accurate prediction. Reliable prediction ranges are determined for the four separate predictors. The reliable prediction range for the two paper machines has a potential of 15 minutes and the R2 is still above 0.8 for that time ahead. The predictions for digesters have an R2 above 0.6 for up to 25 minutes ahead. The steam demand from other components can be predicted with an average error of no more than 9% for 60 minutes ahead.<br>Vid ett integrerat massa- och pappersbruk är ånga den mest vitala energibäraren, den brukas av maskiner och komponenter för massa- och papperproduktionen. Komponenternas arbetscykler skapar svängningar på ångnätet som överstiger vad den installerade ångackumulatorn kan hantera. För att möta det svängande behovet produceras ånga i en sådan takt att ackumulatorn ska hålla hög nivå. Något som skapar perioder med överproduktion och full ackumulator vilket leder till att ånga måste friblåsas förutan energiåtervinning. Av denna anledning har syftet med detta arbete varit att ta fram en prediktionsmodell som kan förse bruket med pålitlig prognos för ångförbrukning. Kunskap om framtida prognoser ska såsmåningom implementeras i styrningen för ackumulatorn samt ångproducenter. Prognoserna ska underlätta att mer effektivt möta kommande behov, större reglerutrymme i ackumulatorn samt mer anpassad produktion. Den färdigställda prediktionsmodellen består av fyra mindre modeller grundade utefter de mest påverkande komponenterna. Den första tillhör de fem batch kokarna, den andra ansvarar för pappermaskin 5 (PM5). Tredje är till pappersmaskin 6 (PM6), slutligen en prediktor för övriga förbrukare. Prediktorerna har skapats utefter teoretiska behov samt relevant historisk data som påverkat energianvändningen. Analyser av korrelationer mellan olika parametrar har skapat prediktionsförmåga för dessa prediktorer. Den kompletta prediktionsmodellen uppvisar potential att leverera pålitlig prognos med förklaringsgrad R2 över 0.7 upp till 60 minuter fram i tiden. Trots att 60 minuters pålitlig prediktion är möjlig kan den inte garanteras. Pålitlig prediktionstid bestämms utifrån vardera enskild prediktor. Pappersmakinera påvisar pålitlig prediktionsförmåga upp till 15 minuter där R2 hålls ovan 0.8 inom den tiden. Kokeriets prediktionstid är 25 minuter där R2 har värden över 0.6. Övriga komponenter påvisar liten skillnad inom 60 minuters prediktionstid. Det genomsnittliga prediktionsfelet överstiger ej 9% inom den tiden.
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Gibbons, Wade N. "Suitability of small fish species for monitoring the effects of pulp mill effluent on fish populations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq21350.pdf.
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Podemski, Cheryl Linda. "Ecological effects of a bleached kraft pulp mill effluent on benthic biota of the Athabasca River." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0019/NQ37908.pdf.
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Bauer, Elizabeth Nanette. "MODIFICATION OF AN EXISTING BENTHAL MODEL FOR PAPER MILL WASTES." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275443.
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Moslehi, Ehsan. "Integrating membrane filtration forwater reuse in tissue mill." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231741.
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Water is an essential and indispensable component is the pulp- and paper production industry.The increase in energy costs, stricter environmental regulations and water resource shortageshave caused a reduction of the water footprint in the industry as well as an increase in waterrecycling and water circuit closure. Reducing water usage requires an understanding of wherecontaminants originate, as well as which streams are critical to the process and how they impactmill operation. The recirculation of water can cause contaminant accumulation; therefore millsemploy technologies for water treatment in the internal water cycles, the so-called ‘kidneys’.Application of membrane technology is one such option which can improve the recycled waterquality and reduce contaminant buildup.The present study was carried out on a lab-scale for the treatment of a tissue mill effluent usingmembrane separation. A combination of pretreatment methods and various membranes werecompared with regards to separation, flux and fouling. The AlfaLaval M20 device was to treatwastewater samples sent from the mill, where the permeate was recirculated to the feed tank.COD and TOC levels are compared with regards to determining the separation efficiency. Thepermeate flux was measured over the two-hour filtration period, as well as flux recovery todetermine fouling levels. Additionally, some economic aspects of the process are discussed.This study suggests the potential application of a combination of flocculation or centrifugationpretreatment, with reverse osmosis membranes for recycling water to replace freshwater intake.The results also indicate the possibility of using ultrafiltration as kidneys to decreasecontamination buildup for further water loop closure.
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Barber, Steven Donald. "Analysis and Prevention of Usable Fiber Loss from a Fine Paper Mill." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/37004.
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Reducing losses of usable waste fiber from paper mills conserves valuable resources and has the capacity to produce considerable economic returns to the manufacturer. The purpose of this research effort was to evaluate the potential for the prevention of loss and/or recovery of usable waste fiber from paper machines within a fine paper mill. Further, a preliminary evaluation of fiber loss prevention strategies and fiber recovery technologies was conducted.
<p>
The paper mill in question experienced losses of usable waste fiber to the sewer in amounts approaching, and sometimes exceeding 40 tons/day. An existing database of usable fiber test results was analyzed to determine patterns of fiber loss. Further testing showed that the most significant fiber losses resulted from centrifugal cleaner cones. These cones, designed to remove foreign material from stock, are one step in a series of mechanical cleaning devices in the stock preparation area of the paper mill. Cleaner cone systems on two of the paper machines were found to contribute most significantly to total fiber loss.
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Contrary to cleaner cone design, the dirt content of fiber rejects from cones experiencing excessive loss was very low. Cleaner cones on other machines operated normally. These rejects were extremely dirty and quantities of fiber were low. These results indicate poor operating efficiency of two of the cleaner cone systems in question. By adding cones where space is available, system capacity and efficiency will increase, fiber losses will decrease, and the dirt content of rejects will increase. This will result in substantial resource and financial savings to the paper mill.
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Technologies have been developed to recover usable fiber from paper mill sludge. However, prior to further investigation of the use of such innovations at this paper mill, efforts should focus on the reduction of fiber loss from point sources.<br>Master of Science
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Small, Contessa. "Occupational narratives of pulp and paper mill workers in Corner Brook, Newfoundland : a study in occupational folklife /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0032/MQ47479.pdf.
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Larson, Robert Blake. "Attenuation of constituents from paper-pulp mill wastewater ponded on clay soil under natural environmental conditions." Thesis, The University of Arizona, 1986. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1985_367_sip1_w.pdf&type=application/pdf.
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Lundmark, Patrik, and Viktor Bergman. "The Influence of Pressure Factors : A case study of a Swedish mechanical pulp and paper mill." Thesis, Halmstad University, School of Business and Engineering (SET), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-5841.
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<p>The authors of this paper will try to identify what different pressure factors have an influence over the Swedish mechanical pulp and paper industry. Moreover, the authors of this paper will try to identify whether different levels of environmental commitment can be identified within the organization.</p><p>The results show that all of the pressure factors that were identified in the case study, except for regulations and social pressure, are influenced by economic benefits and, therefore, a reactive stance is almost always preferred by the firm when there is a negative correlation between economic performance and environmental performance. Results also indicate a gap in the internal communication of the organization. This is not related to the topic of this paper but might be useful information for the company used in the case study.</p>
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Ganta, Madhuri. "Anaerobic digestion of pulp and paper mill solid wastes : evaluation of operational parameters and microbial diversity." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/27081.
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Tripathi, Chandrashekhar. "Thermophilic aerobic biological treatment of bleached kraft pulp mill effluent and its effect on floc formation and settleability." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0001/NQ41328.pdf.
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Tomasini, Federica. "Industrial Demand Response in the Primary Reserve Markets : A case study on Holmen’s Pulp and Paper Mill." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-253260.
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This thesis stems from the interest of Holmen group to investigate the opportunitiesavailable for large electricity consumers in the Swedish primary reserve markets.The study performed focuses on one of Holmen's paper mill and it aims at identifyinga load inside the production process that is suitable for providing frequency containmentservices for the grid. The evaluation of the mill's consumption prole and the technicalrequirements of the reserve market led to the identication of the electric boiler coupledwith a steam accumulator as the most appropriate load.Five case study simulating the participation of the mill to dierent energy and reservemarkets have been evaluated. For each case a linear optimization problem has beenformulated. The rst simulation represents the current practice of the mill in relation tothe energy purchased on the spot market (following it will be also referred as referencecase). The second case study (II c.s.) integrates the use of the steam accumulator asa tool to perform thermal load shifting. In the third case study (III c.s.) the mill ismodelled to bid on the spot and primary reserve market by oering some capacity ofthe electric boiler. The last two case studies (IV and V c.s.) recalls the rst and lastpreviously mentioned, but also include the possibility of having energy imbalance. Thismeans that the imbalance settlement operated by eSett will produce an additional costor prot for the mill.The last three problem formulations fall under the denition of stochastic problems,since two random variable are present, namely: average hourly frequency value andimbalance settlement price. The uncertainty of the variables is represented throughscenarios.The outcome derived from the combination of the results for the winter and summercases shows that each strategy brings an economic saving when compared to the referencecase (I c.s.). The less interesting strategies are the ones that do not involve the reservemarket, leading to about 0.03% (II c.s.) and 0.06% (IV c.s.) of saving on the overallyearly energy cost. Contrariwise, by oering FCR-N capacity, the cost of electricitycan be cut by 5.15% (III c.s.) and 6.69% (V c.s.), respectively considering and notconsidering the imbalance settlement.<br>Avhandlingen har sitt ursprung i skogsindustrikoncernen Holmens intresse att undersökamöjligheten för stora elförbrukare att delta på den svenska primär-reservmarknaden. Studien som utförts fokuserar på ett av Holmens pappersbruk och syftar till att identifiera en elektrisk process som, inom bruksgränserna, är lämplig för att tillhandahålla frekvensregleringstjänster till det nationella nätet. En utvärdering av brukets elförbrukning samt de tekniska krav som ställs på reservmarknaden ledde till att en elektrisk panna med tillkopplad ångackumulator identifierades som mest lämplig.Fem budstrategier som simulerar brukets deltagande till olika energioch reservmarknader har presenterats. För varje strategi är ett linjärt optimeringsproblem formulerat. Den första strategin visar på nuvarande sätt bruket köper elektricitet på spotmarknaden. Den andra strategin integrerar användning av ångackumulatorn som ett verktyg för att utföra termisk lastskiftning. I den tredje modelleras deltagande också på primärreservmarknaden genom att erbjuda en viss kapacitet hos elpannan. De två sista strategierna baseras på den första och tredje, men tillåter i tillägg obalanser vilket innebär en extra kostnad eller möjlig intjäning för bruket.De tre sista problemformuleringarna faller under definitionen stokastiska problem, eftersom två slumpmässiga variabler är närvarande, nämligen: genomsnittligt timfrekvensvärde och priset för obalans. Osäkerheten för variablerna representeras genom scenarier.Resultatet visar att varje strategi ger en ekonomisk besparing jämfört med refer-ensfallet (strategi ett). De mindre intressanta strategierna är de som inte involverarreservmarknaden, vilka endast leder till ca 0,03% och 0,06% minskning av den totalaårliga energikostnaden. Däremot, genom att erbjuda FCR-N-kapacitet kan kostnaden för el minskas med 6,69% och 5,15% beroende s eller ej.
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Kovara, Michael Anthony 1949. "The effect of temperature and overwater dissolved oxygen concentration on benthal feedback from pulp and paper mill sludges." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191913.
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Settleable solids accumulate (benthal layer) in stabilization lagoons, reducing volume for treatment and providing a source of oxygen demand and nutrients (feedback). The objective of this research was to define the impact of overwater dissolved oxygen (DO) and temperature upon these benthal properties. Batch benthal deposits (2:1, vol/vol, primary clarifier underflow and waste activated sludge) under a continuous-flow overwater layer were subject to variable temperature and DO. Experiment conditions simulated a facultative lagoon. Over 124 days, DO uptake was measured and effluent was sampled for chemical oxygen demand (COD), ammonia-N, and ortho-phosphate. Nearly all phosphorus feedback occurred in the first 31 days, and ammonia-N feedback was most constant for the duration. COD feedback was greatly reduced and DO uptake increased slightly with increasing DO. All feedbacks increased more from 15°C to 20°C than from 20°C to 26°C. Residual sludge analyses indicated that phosphorus was limiting to benthal stabilization. Temperature dependent reactions caused a linear decrease in total and volatile suspended solids.
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Gauthier, Francis. "Study of coliform bacteria in Canadian pulp and paper mill water systems : their ecology and utility as health hazard indicators." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33401.
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Coliform bacteria have long been used to indicate fecal contamination of food, water, and solid surfaces, and thus the presence of a health hazard. In this study, the in-mill water and external effluent treatment systems of seven typical Canadian pulp and paper mills were shown to support the growth of numerous coliforms, especially Klebsiella spp, Escherichia coli, Enterobacter spp., and Citrobacter spp . Mill coliforms were shown to be not just simple transients from feedwater or furnish (wood), but to be continuously growing, especially in the primary clarifiers. Therefore, coliforms and fecal coliforms cannot be used as fecal contamination indicators in pulp and paper mill water and effluent treatment systems.<br>N2-fixing coliform populations were detected in mill water systems and were analyzed using N2-fixation assays and nitrogenase gene (nifH) probing. Both active in situ populations and cultured microbial isolates were tested. Active N2-fixation was demonstrated in six primary clarifiers. Measurement of the numbers and composition of the total culturable bacterial community in a primary clarifier revealed that approximately 50% of all aerobic cells contained nifH , of which >90% were Klebsiella. Coliforms growing on MacConkey agar plates from the primary clarifier were all identified as Klebsiella and 100% of these Klebsiella contained the nifH gene. Preliminary estimates indicate that the amount of N2 fixed per day is substantial in some clarifiers.