Literatura académica sobre el tema "Refuse and refuse disposal Recycled products"

In Taiwan, 3,130,735 t of refuse for disposal and 4,113,808 t of recycled recyclable waste were generated in 2017. The government of Taiwan has been actively promoting a resource recycling program since July 1998. To pursue sustainability and locate waste minimization opportunities, the correlation between utility consumption and population and the quantity of refuse and recyclable waste from municipalities in Taiwan was studied. There are six special municipalities and 16 cities and counties covering a great variety of urbanization and settlement characteristics, such as registered populations, electricity, and water consumption. The above parameters of the municipalities were correlated with the quantities of refuse and recycled urban waste. Residential electricity consumption, overall population, and business electricity consumption were found to be major parameters correlating the generation of refuse and recycled urban waste. Due to their higher levels of business activities, the waste generation behaviours of these six special municipalities are more diverse than those of the 16 municipalities. Due to the discrepancy of the registered population system, the utility consumption values within administrative boundaries can better predict municipal solid waste, (MSW) generation than utility consumption at a per capita. Utility consumption within administrative boundaries is more convenient as a measure to predict refuse and recycled urban waste than other complex social–economic indicators.

Pilot-scale investigations on the fate and potential effects of disposable diapers codisposed with shredded municipal refuse were conducted using simulated landfills operated under leachate containment and recycle conditions. Carbon fourteen(14C)-labelled absorbent gelling material (AGM) was used to detect the possible loss of the diaper polymer to the gases and liquids generated during the various stages of landfill stabilization. Only a small quantity (<3%) of the total 14C appeared in either the leachate or gas phases. This indicated only minor degradation of the 14C-labelled AGM to either leachate soluble products or methane (CH4) or carbon dioxide (CO2). Retrieval of the diapers and waste after the completion of the landfill stabilization is scheduled to confirm this finding and complete a 14C mass balance. Moreover, the overall results indicated the effectiveness of landfill simulations for determining the fate and effects of codisposed post-consumer products throughout the sequential phases of landfill stabilization.

Using mathematical programming with activity-based costing (ABC) and based on the theory of constraints (TOC), this study proposed a green production model for the traditional paper industry to achieve the purpose of energy saving and carbon emission reduction. The mathematical programming model presented in this paper considers (1) revenue of main products and byproducts, (2) unit-level, batch-level, and product-level activity costs in ABC, (3) labor cost with overtime available, (4) machine cost with capacity expansion, (5) saved electric power and steam costs by using the coal as the main fuel in conjunction with Refuse Derived Fuel (RDF). This model also considers the constraint of the quantity of carbon equivalent of various gases that are allowed to be emitted from the mill paper-making process to conform to the environmental protection policy. A numerical example is used to demonstrate how to apply the model presented in this paper. In addition, sensitivity analysis on the key parameters of the model are used to provide further insights for this research.

Legal regulations on waste disposal require waste producers to limit landfilling and to find different ways of waste management, the preferred methods being recycling of material and energy potential. Currently, in Poland, the only consumers of refuse-derived fuels (RDF) are cement plants. However, their ability to utilize alternative fuel is far from the estimated potential. One solution would be to redirect the excess fuel to power and heat production facilities. Unfortunately, these sectors are facing a number of problems related to the thermal treatment of waste, mainly formal nature. Co-combustion of waste in power plants raises a lot of concern among their employees and local communities. Especially significant is the harmfulness of usage of fuel from waste for the people’s lives or health, or the environment. The article compares the environmental footprints of the combustion process of: waste - based fuel (RDF) and lignite. The analysis was performed for a standard pulverized coal fired boiler. Comparative assessment was made by analyzing the total environmental impact of all combustion products of the two fuels. Final results have shown, that the environmental footprint of waste-based fuels can be similar or even smaller than traditional coal-based fuels

Landfills in rural, resource-based communities are receiving unknown quantities of potentially hazardous materials, including household hazardous wastes (HHHW) and industrial, commercial, and institutional (ICI) wastes in self-hauled and collection vehicle loads. Rural generation and disposal rates are expected to be higher than in urban areas.The research program was conducted in a resource-based community consisting of a town of about 5500 residents and the surrounding rural area with an equal number of residents in Alberta. The research objective was to determine the weight fraction of hazardous materials in the refuse through physical sampling of the waste stream at the community landfill. Over a 1-year period (1991), large collection vehicle loads and self-hauled private and ICI loads from the town and the rural area were sampled during 1 week in each season using a two-staged systematic random sampling design to measure the average weight fraction and variation by season and by type of load. The results show the annual average weight fraction of hazardous materials to be 6.7% with a 95% confidence interval of 4.0% to 9.4%. Seasonal differences are apparent, but are not significant. Self-hauled ICI and rural wastes tend to contain higher percentages of potentially hazardous materials, but the variation is also higher so the values are not significantly different from those from the town. The detected materials consist mainly of oily wastes (debris, oil containers, and vehicle oil filters), other automotive products, and paints. As a result, the hazardous material content of rural community refuse appears to be substantially higher than the 0.3% to 1.0% reported for HHHW in urban refuse streams. While the rural composition suggests that vehicle and home maintenance contribute some of the difference, this study also shows that ICI wastes and self-hauled loads contribute noticeable quantities of potentially hazardous materials. The results suggest that it is essential for rural communities to consider waste management alternatives for potentially hazardous materials because rural waste streams contain significantly higher percentages and because rural landfills are often not designed to as high a standard as large urban facilities. Key words: household hazardous waste, ICI waste, waste stream analysis, rural landfills, refuse waste stream.

The generation of solid waste around the world creates problems if not properly managed. The method of processing solid waste by burning or landfill is currently not optimal. The availability of land where the final processing (TPA) is critical, looking for a new TPA alternative will be difficult and expensive, especially in big cities. The processing of solid waste using bio drying technology has the potential to produce renewable energy and prevention of climate change. Solid waste processing products can serve as Refuse Derived Fuel (RDF), reduce water content of solid waste, meningkatkan kualitas lindi and increase the amount of recycled solid waste that is not completely separated from home. Biodrying technology is capable of enhancing the partial disintegration and hydrolysis of macromolecule organic compounds (such as C-Organic, cellulose, hemicellulose, lignin, total nitrogen). The application of biodrying has the potential to reduce greenhouse gas emissions such as carbon dioxide (CO2), methane (CH4), and dinitrooksida (N2O). These gases cause global warming.

The County Sanitation Districts of Los Angeles County (Districts) operate a network of six wastewater treatment plants called the Joint Outfall System (JOS) which treat a wastewater flow of approximately 22.3 m3/s (510 mgd). Centralized sludge processing for the JOS is performed at the largest plant in the system, the Joint Water Pollution Control Plant (JWPCP). Sludge is anaerobically digested, dewatered in scroll centrifuges, and either composted and sold to a private company which produces bagged soil amendment products or codisposed with refuse at a site which recovers energy from landfill gas with a 46 net megawatt steam turbine power plant. Future sludge handling will include dehydration followed by incineration for most of the sludge now landfilled. JWPCP accomplishes an environmentally sound and cost effective balance of solids disposal to the air, land and water.

The huge biomass generated by vendors of tender coconut is the broken husks refuse dumped along roads and highways in Kerala. These dumps become breeding grounds for diseased causing germs and carrier mosquitoes causing threat to human life. In order to avoid pollution and find use of the rejected biomass of tender husks, a study was carried out on pulping of tender coconut husk fibre which could be used for papermaking. The optimum pulping condition, the quality of the pulp and its yield was evaluated using different variables like time and temperature. It was observed that the organosolv process could efficiently remove lignin from the tender coconut fibre yielding maximum cellulose. During the traditional pulping processes such as Kraft pulping to isolate the cellulose fibers for the production of paper, the hemicellulose and lignin fractions are degraded, limiting their valorization possibilities. Organosolv pulping has been advocated as the environmentally benign version of the kraft process. Unlike other pretreatment methods, organic solvents can easily be recycled and reused. The lignin dissolved by organosolv pulping is easily recovered by dilution and is unsulphonated and relatively unmodified. Products like handmade paper, egg cartons, handicraft items, garden articles like paper pots could be made from the organasolv pulp of tender coconut husk fibre.

The disposal and reuse of waste combustion residues has become a critical topic recently in view of the method of treating household wastes in a city, which has gradually changed to be incineration (major) and landfill (minor) in densely populated Taiwan, plus the difficulty of various wastes disposed by the Refuse Incineration Plant at Yilan County. To propose concrete recommendations as references for the local competent authorities’ policy for reuse of bottom ash, we researched and analyzed compositions of wastes and ingredients as well as leaching toxicity of bottom ash (accounting for 70% of waste combustion residues) which had been collected from the Li-Ze Incineration plant at Yilan, and transported bottom ash to a cement plant also at Yilan as an alternative material for Portland cement. The results in this study indicated quite a few products, with ingredients of bottom ash from an incineration plant, can be taken as principal compositions used in production of cement, and the capacity of bottom ash treated by the cement plant can be further expanded according to the quality of produced cement and bottom ash properly processed.

There has been a gradual increase in the field of parts recovery from cars that are withdrawn from use. However, the disposal of automotive shredder residue (ASR) still remains a significant problem. ASR is refuse derived fuel (RDF), which contains mainly plastics, fiber sponges, and rubbers in different proportions, and therefore a thermal treatment of selected waste samples is applied. The presented research includes thermogravimetry (TG) analysis and differential thermogravimetric (DTG) analysis, as well as a proximate and an ultimate analysis of the ASR samples. The obtained results were processed and used as an input for modelling. The numerical calculations focused on the identification of the ASR’s average composition, the raw pyrolysis process product, its dry pyrolytic gas composition, and the combustible properties of the pyrolytic gases. The TGA analysis with three heating rate levels covered the temperature range from ambient to 800 °C. The thermal decomposition of the studied samples was in three stages confirmed with three peaks observed at the temperatures 280, 470, and 670 °C. The amount of solid residue grew with the heating rates and was in the range of 27–32 wt%. The numerical calculation of the pyrolysis process showed that only 0.46 kg of dry gas were formed from 1 kg of ASR. The gas yield increased with the rising temperature, and, at the same time, its calorific value decreased from 19.22 down to 14.16 MJ/m3. This is due to the decomposition of C6+ hydrocarbons and the promotion of CO formation. The thermodynamic parameters of the combustion process for a pyrolytic gas air mixture, such as the adiabatic flame temperature and laminar flame speed, were higher than for methane and were, respectively, 2073 °C and 1.02 m/s.

The Second-Hand Society tells the stories of people in Portland, Oregon who redefine waste by making use of objects others discard. The author spends time in repair shops watching craftsmen hammer and polish broken typewriters, vacuum cleaners and shoes back to life. She follows book scouts, clothes pickers and liquidators as they gather merchandise to resell and spends hours at nonprofits that collect and redistribute unwanted electronics and building supplies. She watches junk artists and fashion designers assemble found objects into display pieces, accompanies Dumpster divers and "freegans" along their regular collection routes and visits the homeless encampment by the airport to see how an entire community of people survives on nothing but reclaimed materials. The members of the second-hand society challenge the traditional conception of things as "broken" or "unwanted" and assert that forward movement and new-new-new is not always optimal. By examining the motivations and practices of the people who make use of our discards and looking at the contradictions they run up against, this thesis develops a more complete understanding of the reality that's possible if we think differently about our waste.

Thesis (Doctor of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2017.
The search for alternatives to fossil fuel is necessary with a view to reducing the negative environmental impact of fossil fuel and most importantly, to exploit an affordable and secured fuel source. This study investigated the viability of municipal solid waste gasification for a fuel cell system. Potential solid fuels obtained from the study in the form of refuse-derived fuel (RDF) had high heating value (HHV) between 18.17 MJ/Kg - 28.91 MJ/Kg with energy density increased from 4142.07 MJ/m3 to 10735.80 MJ/m3. The molecular formulas of RDF derived from Ladies Smith drop-off site, Woodstock drop-off site and an average molecular formula of all thirteen municipal solid waste (MSW) disposal facilities were CH1.43O1.02, CH1.49O1.19, and CH1.50O0.86 respectively. The comparative ratios of C/H were in the range of 7.11 to 8.90. The Thermo Gravimetric Analysis showed that the dehydration, thermal decompositions, char combustions were involved in the production of gaseous products but flaming pyrolysis stage was when most tar was converted to syngas mixture. The simulation of RDF gasification allowed a prediction of the RDF gasification behaviour under various operating parameters in an air-blown downdraft gasifier. Optimum SFR (steam flowrate) values for RDF1, RDF2 and RDF3 were determined to be within these values 2.80, 2.50 and 3.50 and Optimum ER values for RDF1, RDF2 and RDF3 were also determined to be within these values 0.15, 0.04 and 0.08. These conditions produced the desired high molar ratio of H2/CO yield in the syngas mixture in the product stream. The molar ratios of H2/CO yield in the syngas mixture in the product stream for all the RDFs were between 18.81 and 20.16. The values of H2/CO satisfy the requirement for fuel cell application. The highest concentration of heavy metal was observed for Al, Fe, Zn and Cr, namely 16627.77 mg/Kg at Coastal Park (CP), 17232.37 mg/Kg at Killarney (KL), 235.01 mg/Kg at Tygerdal (TG), and 564.87 mg/Kg at Kraaifontein (KF) respectively. The results of quantitative economic evaluation measurements were a net return (NR) of $0.20 million, a rate of return on investment (ROI) of 27.88 %, payback time (PBP) of 2.30 years, a net present value (NPV) of $1.11 million and a discounted cash flow rate of return (DCFROR) of 24.80 % and 28.20 % respectively. The results of the economic evaluations revealed that some findings of the economic benefits of this system would be viable if costs of handling MSW were further quantified into the costs analysis. The viability of the costs could depend on government responsibility to accept costs of handling MSW.

Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2016.
The generation of municipal solid waste has increased significantly due to the exponential population growth and it has become a global issue. Gasification technology, an alternative method for waste treatment is a thermochemical process where carbon-based material are exposed to an environment deprived in oxygen, was used for this project. The aim of this thesis is to study the gasification of plastic waste which is a potential alternative energy source using infrared heaters. To achieve this goal, fundamental studies have been numerically and experimentally conducted for an infrared gasifier and subsequently establishing the temperature profile for gasification using a small scale reactor. A detailed study on low density polyethylene was conducted using Infrared Spectrometry and thermal decomposition techniques such as Thermogravimetry and Differential Scanning Calorimetry were performed to establish the temperature at which plastic pellets sample used for this research gasify. The gasification behaviour of pelletized low density polyethylene (plastic pellets) was tested and three case studies were done to evaluate the most suitable temperature profile for the reactor to gasify the low density polyethylene at high temperature for less amount of time. Subsequently, the reactor model was simulated and results validate the use of reactor at an optimum temperature of 800 °C for a gasification process with less residue content. The reactor designed for this research is fully functional and validates the temperature behaviour predicted during simulation. The experimental results show infrared heaters are suitable for gas production using this gasification process.

Thesis (MScEng)--Stellenbosch University, 2002.
ENGLISH ABSTRACT: Can salts present in an aqueous industrial effluent be retained by the [me ash that is produced as a by-product of gasification or by power stations utilising coal as the raw material? In order to answer this question, the actual chemistry that occurs during the mixing and settling process, needs to be understood. At the Sasol Secunda petrochemical plants in South Africa, ash is produced as a byproduct from the gasification of coal, and by the coal-fired power stations (steam plants). The [me portion of the ash (± 50J.lm in diameter) is disposed of through the use of a closed loop wet ash disposal system. The ash is transported as a slurry to the disposal sites (ash darns). The industrial effluent used to transport the ash consists mainly of the recycled ash effluent, known as clear ash effluent (CAE), as well as a variety of process waste streams containing high concentrations of salts. This mixture of ash and water is pumped to ash dams, where the ash is allowed to settle and is therefore separated from the effluent. From the ash darns the effluent flows into evaporation dams, and finally into CAE dams before being returned to the ash plant in Sasol 2 and 3 to be mixed once again with the ash. During this contact time of the ash with the water certain chemical reactions may occur. If one understands what chemical reactions occur during this process, and under what conditions they occur, then it will be possible to utilise the ash disposal system to its full potential, possibly enhancing the salt retention ability. An investigation was thus conducted into what processes actually occurs during the entire ash water contact period. The overall aim of the project was to obtain an understanding of the functioning of the [me ash disposal system so that its efficiency can be improved upon, and furthermore, so that the ash darns can be utilised more effectively in retaining salts. This investigation focussed on the chemical reactions that occur when an industrial effluent is mixed with fine ash, and consisted of four main aspects: • A literature survey on related issues. • An analysis and evaluation of the changes that occur in the actual disposal system. • Laboratory column experiments to investigate, in more detail, the different chemical reactions, which occur during the different stages of the disposal process. • The drilling of boreholes into the ash dams to obtain core material at a variety of depths and locations for analysis purposes. From this investigation it was concluded that salts are retained in the ash dams; based on the results obtained from the laboratory column experiments and the production rate of the fine ash from Sasol 2 and Sasol 3, the potential amount of salts that can be removed from the system (either due to precipitation or water retention in the ash dams) is approximately 95 tons/day. The salts that were found to be most pertinent to the wet ash disposal system utilised at Sasol, Secunda, are Ca, S04, Na, and Cl. Of these, Ca, S04 and Na were identified in literature to be the components most commonly associated with fly ash leachate. The Ca chemistry, which occurs in the ash disposal system, was explored extensively. Is was found that Ca, which is initially present in the fresh fine ash as lime, is leached from the ash into the effluent, where it reacts with carbon dioxide in the atmosphere, and is therefore removed from the system due to the precipitation of calcite. Sodium, S04, and Cl were all found to be retained in the ash; the S04 appears to be retained in a stable form within the ash, not merely due to hydraulic retention, which suggests that the ash system has the potential to act as a salt sink for S04 ions. The mechanism of salt retention in the ash darns was found to be predominantly by means of hydraulic retention, and therefore the salts have the potential to be flushed out of the ash dams into the underlying soil material. However, results from the core drilling exercise revealed that there doesn't appear to be a significant seepage of elements from the ash fill material into the underlying vertisol material. Some components (AI, Fe, Na, K, Mg, Cr, P, Ti and V) from the older, and inactive ash dam, do appear to have percolated into the underlying material. However, a significant amount of water, and therefore salts, are still retained in the ash dam. In terms of the mineralogical composition of the ash dams, a significant difference was observed between the mineral phases present in the ash fill material of an active and an inactive ash dam. Ettringite was detected throughout the borehole drilled into the inactive ash darn, and was not evident at all in the core material from the two boreholes drilled into the active dam, which suggests that this mineral is formed in the ash darns over a long time period. The minerals quartz and mullite were found in the fresh [me ash as well as in most of the core material obtained from the drilling exercise. The mineralogical composition of the ash fill samples, from the boreholes drilled into the centre of the active and inactive ash darns, was found to be very consistent with depth. This finding, combined with the fact that the chemical composition of the core samples varied more significantly in the borehole located near the edge of the active fine ash darn, indicated that the lateral position of the ash in the ash dam influences the chemical reactions that occur. Overall, from this investigation it was concluded that although the chemistry, involved in the mixing of an industrial effluent with fine ash, is extremely complex and site-specific, it is possible to determine the most significant changes which occur within a wet ash disposal system. Besides providing one with a better understanding of the working of the Secunda ash disposal system, the results of this investigation have also provided the framework for future research on this topic and related issues, i.e. the construction of a pilot scale ash darn set-up; further column experiments to investigate the extent to which S04 ions can be removed from the system; the influence of the addition of CO2 to the system; and more extensive core drilling in the vicinity of the ash darns.
AFRIKAANSE OPSOMMING: Kan soute teenwoordig in 'n industriële uitvloeisel teruggehou word in fynas geproduseer as neweproduk van steenkoolkragsentrales? Om 'n antwoord op hierdie vraag te kry, moet die chemiese reaksies wat gebeur tydens die meng en wegdoening van die as en aswater verstaan word. By die Sasol petrochemiese aanlegte in Secunda, Suid Afrika, word fynas geproduseer as 'n neweproduk in die vergassing en die stoomopwekkingprosesse. Die fynas (50)lm diameter) word weggedoen deur 'n geslote nat asstelsel. Die industriële uitvloeisel wat gebruik word vir die vervoer van die as bestaan hoofsaaklik uit hergebruikte aswater (genoem CAE - clear ash effluent), asook 'n verskeidenheid ander prosesafvalstrome wat hoë konsentrasies soute bevat. Die mengsel van as en aswater word in 'n asflodder gepomp na die asdamme, waar die as besink en sodoende geskei word van die waterfase (aswater). Vanaf die asdamme vloei die aswater na verdampingsdamme, en daarna na die CAE damme, vanwaar die CAE weer na die Sasol aanleg teruggepomp word om weer met as gemeng te word. Gedurende die kontak tussen die CAE en as gebeur sekere chemiese reaksies. Indien hierdie reaksies verstaan word, en onder watter toestande dit plaasvind, kan die asdamstelsel tot volle kapasiteit benut word deur moontlik die soutretensie binne die asdam te verhoog. 'n Ondersoek is gedoen om te bepaal watter prosesse plaasvind gedurende kontak tussen die as en water. Die doel van die ondersoek was om 'n beter begrip te kry oor die funksionering van die fynas-wegdoeningstelsel en om te bepaal of die asdamme meer effektiefbedryfkan word om moontlik meer soute te akkommodeer. Die ondersoek het uit vier hoofaspekte bestaan: • Literatuuroorsig, • 'n Analise en evaluering van die veranderinge wat plaasvind oor die asdamstelsel, • Laboratoriumskaal kolomeksperimente om in meer besonderhede die chemiese reaksies wat 'n rol in die aswaterstelsel speel, te bepaal, en • Die boor van toetsgate op die bestaande asdamme om boorkerne te ontleed by bepaalde dieptes en liggings. Uit die ondersoek is bevind dat soute wel in die asdamme behou word. As die kolomtoetse as basis gebruik word, en die produksietempo van fynas vanaf Sasol 2 en 3, dan kan daar 'n potensiële 95 ton soute per dag deur die asstelsel verwyder word (deur hoofsaaklik waterretensie en presipitasie van soute). Die mees prominente soute wat in die Sasol asstelsel voorkom is Ca, S04, Na, en Cl. Vanhierdie soute, is Ca, S04, en Na deur die literatuur geïdentifiseer as komponente wat met vliegas loog geassosieer word. Die Ca chemie, wat in die asstelsel plaasvind, is in besonderhede ontleed. Dit is bevind dat Ca, teenwoordig in die vars fynas as kalk, vanuit die as in die aswater geloog word, waar dit dan met atmosferiese CO2 reageer en dan vanuit die stelselverwyder word deur die presipitasie van kalsiet. Natrium, S04 en Cl word in die as teruggehou. Dit wil voorkom asof die S04 in 'n stabiele vorm in die as teruugehou word, nie net deur die hidrouliese retensie nie en dat die asstelsel dalk as 'n potensiële sink vir S04 kan optree. Die meganisme van soutretensie in die asdamme is hoofsaaklik deur hidrouliese retensie, met die gevolg dat die soute potensieel in die onderliggende grond uitgewas kan word. Die resultate van die boorkernondersoek wys egter dat daar nie beduidende uitwassing van hierdie soute in die grond is nie. Dit wil voorkom of sekere komponente (Al, Fe, Na, K, Mg, Cr, P, Ti en V) van die ou en onaktiewe asdam in die grond geloog is. 'n Beduidende verskil was gevind tussen die minerale fases in die asmateriaal van die aktiewe en onaktiewe asdamme. Ettringiet was teenwoordig deur die hele diepte van die boorkern van die onaktiewe dam, maar was nie teenwoordig in beide boorkerns van die gate op die aktiewe asdam nie. Dit impliseer dat hierdie mineraaloor 'n langer tyd gevorm word. Kwarts en mulliet was deurentyd in al die boorkerne teenwoordig. Die mineralogie van die boorkern van die middel van die aktiewe asdam was baie konstant met diepte (in teenstelling met dié van die boorkern op die kant van die asdam) wat daarop dui dat die laterale posisie van die as in die asdam die chemiese reaksies wat mag plaasvind kan beïnvloed. Die ondersoek bevestig dat alhoewel die chemiese reaksies betrokke in die aswaterstelsel baie kompleks en liggingspesifiek is, die mees beduidende veranderinge wat in die asstelsel plaasvind, wel bepaal kan word. Die ondersoek het benewens 'n beter begrip van hoe die asdamme reageer, ook 'n raamwerk gegee vir verdere navorsing in hierdie veld, bv. die bou van 'n loodsskaal-asdam, verdere kolomtoetse om die vermoë van die asstelsel om S04 ione te verwyder te bepaal en die invloed van gemanipuleerde kalsiet presipitasie deur die byvoeging van CO2.

Municipal solid waste incineration (MSWI) is the most widely used solution in those countries where landfilling areas are limited. Incineration allows reducing the total volume of waste (up to 90%) and generating energy resulting from combustion. The main by-product generated in waste-to-energy plants is known as incineration bottom ash (IBA), which is a heterogeneous mixture of ferrous and non-ferrous metals, ceramics, and glass. IBA is classified as a non- hazardous material due to its composition rich in calcium oxide, silica, and iron. IBA composition and morphology are very similar to natural siliceous aggregates after an ageing treatment where the weathered bottom ash (WBA) is obtained. This maturation process makes feasible the WBA valorisation as a secondary aggregate in the field of construction and civil engineering. Moreover, the high percentage of glass and aluminium found in the WBA would allow its valorisation as a precursor in the alkali-activated binders (AABs) formulation. The main goal of this PhD thesis was the scientific and technological development of new AABs based on the alkali activation of WBA (AA-WBA binders), to reduce the use of ordinary Portland cement (OPC) in building and civil engineering fields. In this sense, this aim is related to the use of more sustainable cement-based materials, which promote the circular economy and zero-waste principle through the valorisation of WBA. The potential of WBA as a precursor in the AA-WBA binders’ formulation was evaluated along with the PhD thesis through different studies that can be classified into four blocks. The first block was based on the evaluation of the WBA potential as a precursor in AABs based on its particle size. This study demonstrated the variability in the reactive SiO2 and Al2O3 availability as a function of the particle size. The potential of the entire fraction (EF) and the 8-30-mm fraction highlighted the possible use of them as precursors in the AABs formulation. The second block of this thesis was focused on the study of AA-WBA binders using the WBA as a sole precursor. Mixtures of sodium silicate (WG) and NaOH (2M, 4M, 6M, and 8M) were used as alkaline activator solutions to assess the effect of the NaOH concentration on the final properties. It was demonstrated the possibility of developing AA-WBA. The influence of alkaline activator solution concentration on the final properties of the AA-WBA was evidenced, obtaining better mechanical performance with the use of the WG/NaOH 6M solution. The results revealed the enhancement in the mechanical properties when the 8-30-mm fraction was used. However, the environmental results revealed arsenic and antimony leaching values that require further research to validate the environmental feasibility of AA-WBA. In the third block, the 8-30-mm fraction was mixed with other precursors with greater availability of Al2O3 (metakaolin and PAVAL®). The main purpose was to improve the mechanical properties and the heavy metal stabilisation effect of the AA- WBA obtained in the second block. In both cases, mechanical performance was improved due to the inclusion of Al2O3. However, the environmental properties continued to show leaching values that did not ensure the environmental viability of the AA-WBA binders. Finally, the fourth block of the thesis was focused on carrying out an environmental and ecotoxicological assessment to validate the use of AA-WBA binders as construction material. The results showed a medium-low level of ecotoxicity in the AA-WBA formulated with the 8-30-mm fraction, similar to the binders activated with MK (AA-MK).
El principal subproducte generat durant la incineració de residus sòlids urbans es coneix com a cendra de fons. La seva composició és molt similars als agregats silícics naturals després d’un tractament d’envelliment on s’obté la cendra de fons madurada (weathered bottom ash; WBA segons les sigles angleses). El seu alt contingut en vidre i alumini el converteixen en un potencial candidat com a precursor en la fabricació d’aglutinants activats alcalinament (alkali-activated binders, AABs segons les sigles angleses). L’objectiu principal d’aquesta tesi doctoral va consistir en el desenvolupament de AABs mitjançant l’activació alcalina de WBA (aglutinants AA-WBA). El potencial de la WBA i els aglutinants AA-WBA es va avaluar mitjançant diferents estudis que es poden classificar en quatre blocs. Al primer bloc es va avaluar el potencial de WBA com a precursor en funció de la seva mida de partícula. Aquest estudi va demostrar el potencial de la fracció sencera i de la fracció 8-30 mm. El segon bloc es va centrar en l’estudi d’aglutinants AA-WBA que utilitzaven el WBA com a únic precursor. Es va evidenciar la influència de la concentració de la solució activadora alcalina en les propietats finals dels aglutinants AA-WBA. Els resultats van revelar la millora de les propietats mecàniques quan es va utilitzar la fracció 8-30 mm. No obstant, els resultats ambientals van revelar valors de lixiviació d'arsènic i antimoni que requerien la validació a nivell ambiental dels aglutinants. Al tercer bloc, la fracció 8-30 mm es va barrejar amb altres precursors rics en d’Al2O3 (metakaolin i PAVAL®) per millorar les propietats mecàniques i l’estabilització de metalls pesants dels aglutinants obtinguts al segon bloc. En ambdós casos, es va millorar el rendiment mecànic, tot i que les propietats ambientals van continuar mostrant valors de lixiviació que no asseguraven la viabilitat ambiental dels aglutinants AA-WBA. Finalment, al quart bloc es va realitzar una avaluació ambiental i ecotoxicològica per validar l’ús d’aglutinants AA-WBA com a material de construcció. Els resultats van mostrar un nivell mitjà-baix d’ecotoxicitat a l’AA-WBA formulat amb la fracció de 8 a 30 mm, similar als aglutinants activats amb MK (AA-MK).

This study was conducted in South Africa. South Africa is the first country within the Southern African Development Community to have regulated plastic shopping bags waste through the imposition of both a standard on thickness and a levy. Given this scenario, the Plastic Bags Regulations present an illustrative case for researching complexity, uncertainty and controversies surrounding a new trend in environmental policy making, namely waste product regulation. The thesis focuses on understanding and investigating tensions, debates and responses emerging from the policy process as actors and actor-networks put not only the Plastic Bags Regulations asfocal actant (token) but also other actants and actant-networks as well. To this end, a research question that addressed environmental policies, tensions, debates and responses that informed the development of South Africa's Plastic Bags Regulations was spelt out. The research objectives included the need to: (I) analyse selected international environmental policy processes surrounding plastic shopping bags litter and waste regulation and how these influenced developments in South Africa; (2) identify actors, actants and actor/actant-networks that shaped and were being transformed by South Africa's Plastic Bags Regulations and explain the tensions, debates and responses arising in the policy processes; (3) identify environmental policy outputs and assess outcomes emerging from the formulation and implementation of South Africa's Plastic Bags Regulations; and (4) establish patterns in environmental policy process reforms around South Africa's Plastic Bags Regulations. The language of actors (human), actants (non-human) and actor/actant-networks brings to the fore the aspects of processes and relationships that exist around them. As such, insights from the actor/actant-network theory (AANT) were drawn upon to inform the research. AANT enquiry framework collapses binaries such as nature/society, art/science, structure/agency and global/local historically associated with a particular type of social theory. AANT also denies that purely technical, scientific or social relations are possible (the notion of quaSi-objects or token). Data sets were generated following' the Plastic Bags Regulations as token actant with time frames ranging from prior to, during and after the formulation of the regulations. Similarly, data analysis drew insights from AANT's four moments of translation namely problematisation, interessement, enrolment and mobilisation, with the intervention theory providing an evaluative perspective that complemented AANT. The findings were that after the promulgation of the first draft of the Plastic Bags Regulations in May 2000, tensions emerged around the nature of regulation (whether command and control - preferred by government or self regulation - preferred by industry and labour). In this regard the latter group raised concerns about jobs, income and equipment loss as well as the need to have a holistic approach to waste management rather than targeting a single product at a time whilst the former maintained that this would not be so. As such, education, awareness and stringent antilitter penalties were proposed by industry and labour as sustainable responses to the problem of plastic shopping bags waste rather than regulation. These debates continued and resulted in minor amendments to the original regulations as finalised by Government in May 2002. However, industry and labour continued lobbying government resulting in the conclusion of the Plastic Bags Agreement in September 2002 and the ultimate repulsion of the May 2002 regulations in May 2003. As revealed by this research, these responses led to broader social responses and further tensions as demand for plastic shopping bags went down by about 80% although an estimated 1000 jobs were lost and a number of companies lost equipment and business (with some closing down) following the implementation of the regulations. During implementation, debates emerged around the need to promote locally made carry facilities with two alternatives in sight namely: the Green Bag and the Biodegradable Plastic Bag. Debates also took place regarding enforcement of the new law resulting in the amendments of various pieces of legislation including the Environmental Conservation Act, Environmental Management Act and the Revenue Laws Act. Overall, a 15-year policy reform cycle and sub-cycles was determined. The research also established that the government considered the regulations a success and was already implementing simi lar initiatives to regulate other waste products, among them, used tyres, used oil and glass, confirming the trend towards waste product regulation in South Africa. From these research findings, a series of conceptual frameworks were drawn up to clarify the nature of tensions, debates and responses surrounding certain lead actors, actants and actorlactant-networks. Some of the conceptual frameworks that emerged around the actors and actor-networks include Organised Government, Organised Industry and Organised Labour. Conceptual frameworks that emerged around key actants and actant-networks include the Integrated Pollution and Waste Management, Plastic Bags Regulations as well as the discourses surrounding the Green bag and biodegradable plastic bags. The thesis concludes by reflecting on how the above and the grand actor/actant-network conceptual frameworks emerging from this research might be adopted with varying degrees of flexibility to research environmental and waste management policy processes in different waste product regulation set-ups.
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D’après les limites d’acceptation pour la mise en décharge des déchets, les REFIOM (Résidus d’Epuration des Fumées d’Incinération d’Ordures Ménagères) sont considérés comme déchets dangereux, car ils libèrent des quantités importantes de chlorures et de métaux lourds lorsqu’ils entrent en contact avec de l’eau. Ces solides doivent par conséquent être traités avant leur mise en décharge. A côté des traitements visant l’acceptabilité des REFIOM en décharge, quelques recherches entrevoient la possibilité de valoriser ces résidus, notamment dans des matériaux cimentaires.

Les recherches présentées ici s’inscrivent dans cette tendance nouvelle et visent l’élaboration d’un procédé combinant traitement et valorisation des REFIOM.

Les REFIOM représentent en fait différents types de résidus provenant des installations que rencontrent les fumées issues de l’incinération des déchets. La composition des résidus diffère selon leur origine. Il est dès lors apparu essentiel de considérer chaque type de résidu séparément et de poursuivre l’élaboration d’un traitement sur un seul type de REFIOM. Nous avons choisi de concentrer les recherches sur les Cendres Volantes de Chaudière (CVC), ces résidus se retrouvant dans tout incinérateur.

Le traitement des CVC est basé sur l’extraction de fractions valorisables et la séparation de fractions contaminées, permettant d’obtenir des résidus acceptables en décharge ou, idéalement eux-mêmes valorisables.

Une séparation magnétique permet d’extraire environ 10% en poids des CVC mais ne semble pas exploitable dans le cadre du traitement des CVC car les particules magnétiques contiennent des impuretés (composés non magnétiques) et que le résidu final reste contaminé.

Une étude de la répartition des éléments en fonction de la taille des particules (granulochimie) est effectuée sur les CVC. Il apparaît intéressant de séparer la fraction inférieure à 38 µm obtenue lors d’une séparation granulométrique, effectuée en voie humide en utilisant une solution dense. En effet, cette fraction semble être nettement plus contaminée en Pb (soluble) que le reste des CVC. Une telle séparation constitue dès lors la première étape du traitement des CVC. Elle est suivie par des étapes de lavage des fractions obtenues, visant à extraire les sels solubles (chlorures et métaux). Les lavages sont envisagés à contre-courant afin d’utiliser au mieux l’eau de lavage. Une recirculation interne des solutions est également prévue, de sorte que, théoriquement, le procédé ne génère pas d’effluents liquides. Une étape de précipitation de composés métalliques (PbS dans ce cas-ci) est prévue après le lavage des boues.

Le procédé de traitement des CVC produirait ainsi des boues et des granulats décontaminés, des sels et des précipités métalliques. Seules certaines étapes du procédé ont été investiguées en laboratoire ;des essais supplémentaires sont encore nécessaires pour optimiser chaque étape, comprendre les phénomènes physico-chimiques qui se produisent et assurer des filières de valorisation.

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Municipal Solid Waste Incineration (MSWI) fly ashes and Air Pollution Control (APC) residues are considered as hazardous waste according to the limits for the acceptance of waste at landfills, because high amounts of chlorides and heavy metals leach from the solids when those are in contact with water. These residues have thus to be treated before they can be accepted in landfill. Several treatments aim to limit the leaching of the residues. Beside these treatments, some research works go further the treatment and consider the valorisation of MSWI fly ashes and APC residues, e.a. in cementitious materials.

The present work follows the new trend and aims to build up a process that combines treatment and valorisation of MSWI fly ashes and APC residues.

MSWI fly ashes and APC residues come from the devices encountered by the flue gases from waste incineration. The residues composition differs according to their origin. It seems thus essential to consider each type of residues separately and to develop the treatment only on one sort of residue. Boiler Fly Ashes (BFA) were chosen because they exist in every modern MSWI plant.

The BFA treatment is based on the extraction of valorisable fractions and on the separation of contaminated fractions, which makes the final residues less hazardous; these final residues would then be acceptable in landfill, or, even better, be valorisable.

A magnetic sorting extracts ~10% (wt.) of BFA; however, such a separation would not be useful in a treatment process because the magnetic particles contain some impurities (non magnetic particles) and the final residue is still hazardous.

The repartition of the elements according to the particles size has been studied on BFA. It seems interesting to separate the BFA at 38 µm by a wet sieving process using a dense solution. The lower fraction presents a higher contamination in Pb (soluble) than the larger. Consequently, the first step of the BFA treatment consists of a wet sieving. Washing steps follow the sieving and aim to extract soluble salts (chlorides, heavy metals). These washings work in a counter-current way to optimise the use of water. The solutions are recycled in the process, which implies the absence of liquid effluents. A precipitation step of some metallic compounds (PbS in this case) is foreseen after the washing of the lower fraction.

The BFA treatment process would produce decontaminated sludge and coarse fractions, salts and metallic compounds. Some steps of the process have been investigated at lab-scale; further studies are necessary to optimise each step, to understand the observed reactions and to guarantee valorisation channels.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

For some years, the massive spreading of technically complex products as well as the shortening of product life cycles have led to a constantly rising return flow of discarded technical devices. The removal of these devices today occurs mostly through disposal-oriented strategies, i.e. used products are shredded and finally stored in dumps or eliminated thermally in domestic refuse combustion plants. For a long time, the product flow was a one-way street. Public and legal pressure have led to an increase in the importance of environmentally-oriented aspects in both the industrial and private sector. This leads to a rising demand for the establishment of a cycle-oriented economy. The cycle-oriented economy aims to keep materials and products in economic circulation as long as possible. The objective of the cycle-oriented economy is motivated by the shortage of resources (energy and raw materials) and the shrinking of disposal areas (air, water, soil), as well as the realization that economically usable potentials are currently being thrown away (Gupta and Veerakamolmal, 1999). Disposal, as central component of the cycle-oriented economy, includes recycling. Recycling includes disassembly as a type of treatment. In contrast to other types of treatment, disassembly permits a higher maintenance of value of old products; however, it usually requires a higher expenditure as well. In contrast to alternative types of treatment (i.e. shredding), the recovery of functional components and assemblies for reuse (product recycling) and the possibility of the recovery of materials (material recycling) are possible advantages of conducting a disassembly process (Seliger and Kriwet, 1993). In general, disassembly follows the same objectives as production; thus remanufacturing is often spoken of (Rautenstrauch, 1999).

We are a wasteful lot on planet Earth. We do not mean to be, but this is an inherent and unavoidable feature of human society. The processes of living, eating, working, playing, and dying all utilize consumer products whose production and use generate wastes. Every candy bar has a wrapper; every apple has a core. It is almost impossible to think of a process that does not create some waste. There is sawdust from cutting lumber, metal shavings from drilling and soldering circuit boards, sludges from chemical processes, leftover food from restaurants, waste paper by the ton from environmental hearings and other legal proceedings, dirty diapers, and other household garbage. Societal wastes range from the refuse produced by every family to highly toxic industrial wastes from the production of specialized goods such as electronics, computers, cars, petrochemicals, and plastics. Virtually every aspect of our daily lives generates waste. Waste cannot be avoided. But what happens to all this waste? Some of it is recycled. During the past ten years there has been a growing realization that our globe is finite in its resources, and that the environment is under considerable stress and is being quietly but relentlessly despoiled. In response, streetside “blue box” and other recycling programs have sprouted. Approximately 20% of municipal waste in North America is currently being recycled: metal cans are going back to smelters, paper back to pulp mills, and glass and plastic to factories to be turned into new products. Recycling programs are still expanding, and it is anticipated that in the future as much as 50%, and perhaps even more, of all household and commercial waste will be recycled. Some of the waste is incinerated. When this is accompanied by generation of electricity or useful steam or heat, it can be viewed as a form of recycling—the conversion of waste to energy, a very useful product. It also helps preserve precious nonrenewable resources such as gas, oil, and coal. Many people, however, are concerned about the emissions that are released into the air and the ash that is produced. About 18% of municipal solid waste in the United States is currently being incinerated, with about 75% of the incinerators generating energy (EPA, 1994).

The Mojave Desert and Mountain Recycling Authority is a California Joint Powers Authority (the JPA), consisting of nine communities in California’s San Bernardino County high desert and mountain region. In August 2008 the JPA contracted with Gershman, Brickner & Bratton, Inc. (GBB) to prepare the Victor Valley Resource Management Strategy (Resource Management Strategy). Working with RRT Design and Construction, Inc. (RRT), GBB prepared a coordinated forward-looking strategy to guide the JPA’s future program and facilities decisions. The Resource Management Strategy focused on the Town of Apple Valley, population 70,092, and the City of Victorville, population 107,408, the two largest JPA member communities, which have a combined total of more than 130,000 tons per year of material entering the JPA’s recycling system and the Victorville Landfill. The Resource Management Strategy is underpinned by a characterization of waste loads delivered to the Victorville Landfill. A visual characterization was carried out by RRT in September/October 2008. RRT engineers identified proportions of materials recoverable for recycling and composting among all loads collected from residential and non-residential generators for a full week, nearly 300 loads total. The JPA financed and manages the operations contract for the highly automated Victor Valley Material Recovery Facility (MRF). The MRF today receives and processes an average of 130 tons per day (tpd), five days per week, of single stream paper and containers and recyclable-rich commercial waste loads. The waste characterization indicated that as much as 80 percent of loads of residential and commercial waste currently landfilled could be processed for recycling and composting in a combination manual and automated sorting facility. Residue from the MRF, which is predominated by paper, would provide potential feedstock for an energy recovery project; however, the JPA has two strategies regarding process residue. The first strategy is to reduce residue rates from existing deliveries, to optimize MRF operations. An assessment of the MRF conducted by RRT indicated that residue rates could be reduced, although this material would continue to be rich in combustible materials. The second strategy is to increase recovery for recycling by expanding the recyclable-rich and organics-dense waste load deliveries to the MRF and/or a composting facility. The Resource Management Strategy provided a conceptual design and cost that identified projected capital and operations costs that would be incurred to expand the MRF processing system for the program expansion. Based on the waste composition analysis, residue from a proposed system was estimated. This residue also would be rich in combustible materials. The December 2008 California Scoping Plan is the roadmap for statewide greenhouse gas emission reduction efforts. The Scoping Plan specifically calls out mandatory commercial recycling, expanded organics composting (particularly food residue), and inclusion of anaerobic digestion as renewable energy. The Resource Management Strategy sets the stage for JPA programs to address Scoping Plan mandates and priorities. California Public Resources Code Section 40051(b) requires that communities: Maximize the use of all feasible source reduction, recycling, and composting options in order to reduce the amount of solid waste that must be disposed of by transformation and land disposal. For wastes that cannot feasibly be reduced at their source, recycled, or composted, the local agency may use environmentally safe transformation or environmentally safe land disposal, or both of those practices. Moreover, Section 41783(b) only allows transformation diversion credit (10 percent of the 50 percent required) if: The transformation project uses front-end methods or programs to remove all recyclable materials from the waste stream prior to transformation to the maximum extent feasible. Finally, prior to permitting a new transformation facility the California Integrated Waste Management Board is governed by Section 41783(d), which requires that CIWMB: “Hold a public hearing in the city, county, or regional agency jurisdiction within which the transformation project is proposed, and, after the public hearing, the board makes both of the following findings, based upon substantial evidence on the record: (1) The city, county, or regional agency is, and will continue to be, effectively implementing all feasible source reduction, recycling, and composting measures. (2) The transformation project will not adversely affect public health and safety or the environment.” The Resource Management Strategy assessed two cement manufacturers located in the high desert region for their potential to replace coal fuel with residue from the MRF and potentially from other waste quantities generated in the region. Cement kilns are large consumers of fossil fuels, operate on a continuous basis, and collectively are California’s largest source of greenhouse gas emissions. The Resource Management Strategy also identified further processing requirements for size reduction and screening to remove non-combustible materials and produce a feasible refuse derived fuel (RDF). A conceptual design system to process residue and supply RDF to a cement kiln was developed, as were estimated capital and operating costs to implement the RDF production system. The Resource Management Strategy addressed the PRC requirement that “all feasible source reduction, recycling and composting measures” are implemented prior to approving any new “transformation” facility. This planning effort also provided a basis for greenhouse gas reduction analysis, consistent with statewide initiatives to reduce landfill disposal. This paper will report on the results of this planning and the decisions made by the JPA, brought current to the time of the conference.

Waste to Energy (WTE) is a viable and vital resource to Ireland. Due to its geographic location, strategically located between the U.S. and Europe, Ireland has inherent advantages when it comes to gaining technical knowledge. As an island country with its size it has exaggerated waste elimination problems. Power generation in Ireland is distorted by the size of the island and Irelands recent high-tech business boom has had an affect too. These two items, power and waste, overlap and can be addressed (in part) with one solution. Products not produced in Ireland are imported. The residue of these products is garbage. Therefore the garbage is constantly being imported to the island and never expelled. Landfill space in Ireland is diminishing — rapidly. “Not in my backyard!” is a principal attitude of the public and with good reason. Refuse is a health threat. Landfill tax legislation is changing and the price is rising to €19/tonne and heading for €32/tonne. Converting waste to energy as part of a recycling process garnishes public support because the resource of rubbish is managed in a manner that appeals to common sense. It is a solution that takes into account the public health and providence of the island. If waste is sorted and classified as economically recyclable (i.e. marketable) it is reclaimed and reused. If waste is sorted and classified as economically un-recyclable by conventional methods it is then evaluated for its energy value in power generation and thermal conversion to basic elemental products. The classification process determines the value of waste products, therefore the economic implications of their use either by recycling the waste and thermally eliminating it while generating electricity and/or by producing recycled products. This paper presents a waste recycling/generation project concept that includes waste stream separation, refuse-derived fuels, waste gasification/generation and renewable power resource integration.

The continuous rise in population, urbanization and expansion of cities has triggered a corresponding increase in construction and demolition activity. The frequent collapse of buildings attributed to poor structural design, building decay, and/or use of substandard materials has generated a substantial increase in construction refuse, also referred to as Construction and Demolition (C&D) Waste. This waste stream originates from residential, commercial, agricultural, institutional and industrial building projects for new builds, reconstruction, expansion, and refurbishments/rehabilitation. Most studies in Nigeria have generally focused on solid waste management without considering the uniqueness of C&D and giving it the attention needed, in order to achieve sustainable urban spaces that are highly functional, safe, convenient, and livable. This study seeks to investigate the different approaches and processes of C&D waste management in the City of Jos, in the Plateau State of Nigeria. The mix method was adopted for this research whereby quantitative and qualitative data was collected through a structured questionnaire for construction enterprises, as well as face-to-face interviews with the agencies responsible for waste management in the city. A total of 21 construction companies (representing about 10%) were randomly selected for questionnaire administration while interviews were conducted with the Plateau Environmental Protection and Sanitation Agency (PEPSA) and the Jos Metropolitan Development Board (JMDB) who are responsible for waste management. Investigations revealed that C&D waste consists of heavy and non-degradable materials such as: sheet metal roofing, sand, gravel, concrete, masonry, metal, and wood to mention only a few. The construction companies are solely responsible for: the collection, storage, transportation and disposal of wastes generated from their activities. Approximately 60-70% of the C&D waste materials are either reused, recycled or resold, while the remaining residual waste is indiscriminately disposed. Although the PEPSA and JMDB are responsible for waste management, their focus has been on establishing solid non-hazardous waste infrastructure systems, policies and plans. The absence of records of the quantity of C&D waste generated, the lack of financial data, and the omission of policies and plans for the C&D waste stream has resulted in a missed opportunity for a comprehensive and sustainable waste management strategy for the City and the state. To protect public health, valuable resources, and natural ecosystems, it is recommended that the C&D waste stream be included as part of the state’s waste management program, in consideration of the growing construction and demolition activity, by including C&D policies and guidelines.

In the summer of 2009, Governor John P. DeJongh, Jr. announced that the Virgin Islands Water and Power Authority (WAPA) had just signed two 20-year Power Purchase Agreements, and the Virgin Islands Waste Management Authority (VIWMA) had signed two 20-year Solid Waste Management Services Agreements with affiliates of Denver-based Alpine Energy Group, LLC (AEG) to build, own, and operate two alternative energy facilities that will serve the residents of St. Croix, St. John, and St. Thomas. The alternative energy facilities, to be built on St. Croix and St. Thomas, have a projected cost of $440 million and will convert an estimated 146,000 tons per year of municipal solid waste into refuse-derived fuel (RDF) using WastAway Services® technology, which will be combined with petroleum coke as fuel in fluidized bed combustion facilities to generate steam and electric power. These sustainable projects will provide 33 MW of electric power to St. Thomas and St. John and 16 MW of electric power to St. Croix, and will help to provide long-term cost stability for electric power and solid waste management in the Territory. Construction is expected to start in spring 2010 with an anticipated completion date during the fourth quarter of 2012. This procurement is a significant achievement for the U.S. Virgin Islands. When the projects are fully implemented, they will allow the Territory to reduce its dependence on oil, recover the energy value and certain recyclable materials from its municipal solid waste, and divert this waste from landfill. Since VIWMA has the responsibility to collect and/or dispose of solid waste year-round, having a system incorporating multiple solid waste processing lines and an adequate supply of spare parts on hand at all times is crucial to meeting the daily demands of waste receiving and processing, and RDF production. Also, with the location of the US Virgin Islands in a hurricane zone, and with only one or two combustion units available in each Project, the ability to both stockpile waste pre-RDF processing and store the produced RDF is very important. Gershman, Brickner & Bratton, Inc. (GBB)’s work has included a due diligence review of the Projects and providing professional support in VIWMA’s negotiations with AEG. GBB’s initial primary assignment centered on reviewing the design and operations of the RDF processing systems that will be built and operated under the respective Service Contracts. VIWMA needed to undertake a detailed technical review of the proposed RDF processing system, since this was the integration point of the waste collection system and waste processing/disposal services. GBB, in association with Maguire, was requested to provide this review and present the findings and opinions to VIWMA. In the completion of this effort, which included both a technical review and participation in negotiations to advance the Service Contracts for the Projects, GBB made direct contact with the key equipment suppliers for the Projects proposed by AEG. This included Bouldin Corporation, the primary RDF processing system supplier, with its patented WastAway technology, and Energy Products of Idaho, the main thermal processing equipment supplier, with its fluidized bed combustion technology and air pollution control equipment. Additionally, since the combustion systems for both Projects will generate an ash product that will require marketing for use and/or disposal over the term of the Service Contracts, GBB made contact with LA Ash, one of the potential subcontractors identified by AEG for these ash management services. Due to the nature of the contract guarantees of VIWMA to provide 73,000 tons per year of Acceptable Waste to each Project for processing, VIWMA authorized GBB to perform a current waste stream characterization study. Part of this effort included waste sorts for one week each in February 2009 on St. Croix and March 2009 on St. Thomas, with the results shared with VIWMA and AEG, as compiled. The 2009 GBB waste stream characterization study incorporated historical monthly waste weigh data from both the Bovoni and Anguilla Landfills that were received from VIWMA staff. The study has formed a basis for continuing to augment the waste quantity information from the two landfills with the additional current monthly results compiled by VIWMA staff going forward following the waste sorts. The final GBB report was published in December 2009 and includes actual USVI landfill receipt data through August 31, 2009. The information contained in this document provides the underpinnings to allow for better tracking and analysis of daily, weekly and monthly waste quantities received for recycling, processing and disposal, which are important to the overall waste processing system operations, guarantees and cost projections. GBB’s annual projections are that the total waste on St. Croix is currently over 104,000 tons per year and over 76,000 tons per year on St. Thomas. The thermal processing technology selected for both Projects is a fluidized bed process, employing a heated bed of sand material “fluidized” in a column of air to burn the fuel — RDF and/or Pet Coke. As such, the solid waste to be used in these combustion units must be size-reduced from the myriad of sizes of waste set out at the curb or discharged into the large roll-off boxes or bins at the many drop-off sites in the US Virgin Islands. While traditional RDF would typically have several days of storage life, the characteristics of the pelletized RDF should allow several weeks of storage. This will be important to having a sound and realistic operating plan, given the unique circumstances associated with the climate, waste moisture content, island location, lack of back-up disposal options and downtime associated with the Power Generation Facility. During the negotiations between AEG and VIWMA, in which GBB staff participated, in addition to RDF and pelletized RDF as the waste fuel sources, other potential fuels have been discussed for use in the Projects and are included as “Opportunity Fuels” in the Service Contracts. These Opportunity Fuels include ground woody waste, dried sludges, and shredded tires, for example. Therefore, the flexibility of the EPI fluidized bed combustion boilers to handle multi-fuels is viewed as an asset over the long term, especially for an island location where disposal options are limited and shipping materials onto and off of each island is expensive. This presentation will provide a unique behind-the-scenes review of the process that led to this historic agreement, from the due diligence of the proposed technologies, to implementation planning, to the negotiations with the contractor. Also discussed will be the waste characterization and quantity analysis performed in 2009 and the fast-track procurement planning and procurement of construction and operating services for a new transfer station to be sited on St. Croix.