Dissertations / Theses on the topic 'Trickling filter'

Anionic surfactants are wildly used in many industrial and household applications. Because anionic surfactants are used so widely, significant attention has focused on the removal of these contaminants from wastewater. Among various treatment techniques, biofiltration, such as trickling filter technologies, has been employed in many wastewater treatment plants (WWPTs) to remove anionic surfactants. However, current knowledge of the efficacy of trickling filter to remove anionic surfactants from wastewaters is limited. The present study characterized the performance of a high rate (i.e. roughing) trickling filter to remove anionic surfactants both at lab-scale and pilot-scale. Lab-scale tests investigated the biodegradation of anionic surfactants under controllable conditions were compared with those from previous studies by others. Pilot-scale tests investigated the efficacy of a trickling filter at removing anionic surfactants from a wastewater over an extended period of time. The data from the pilot-scale tests were used to model the performance of trickling filter at removing anionic surfactants from the wastewater, using first order and modified Velz models. The lab-scale tests indicated that high molecular weight anionic surfactants degrade faster than the low molecular weight surfactants. The biodegradation rates observed in the present study were similar to those from pervious studies by others. The pilot-scale tests indicated that roughing trickling filter could remove 11% to 29% of anionic surfactants and 4% to 22% of COD from the wastewater. Higher molecular weight anionic surfactants were more degradable. The experimental data could be accurately modeled using the modified Velz model (R² value more than 0.9). The degradation rates of modified Velz model for total anionic surfactants, high molecular weight anionic surfactants and COD were 0.053±0.0057, 0.088±0.0048 and 0.119±0.0111 (mIs)0.5 respectively. The pilot-scale test results indicated that a high rate (i.e., roughing) trickling filter was not capable of effectively removing anionic surfactants in the primary effluent at Lions Gate WWTP because a relatively large trickling filter area would be required to achieve the required surfactant removal efficiency.

The low-rate trickling filter is the most common biological treatment process used in small and medium sized sewage works in the UK. It produces an inconsistent effluent quality, which has traditionally been related to seasonal changes in solids accumulation, grazing activity and sloughing of microbial film. The final effluent solids and, organic matter content is then too high for discharge or reuse. Given the increasingly stringent effluent standards, both in terms of quality and consistency, tertiary treatment is often required. This study was designed to investigate the key parameters affecting the performance of low-rate trickling filters and the characteristics of their effluents in terms of contaminant size, which might influence the efficiency of crossflow filtration as a tertiary treatment for the trickling filter.

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Includes bibliographical references.
In South Africa, many wastewater treatment plants (WWTP) still make us of their rock filled trickling filters. Instead of using them for organics removal and nitrification, there is growing interest in integrating them with biological excess P removal activated sludge (BEPRAS) systems in an external nitrification flow scheme (Hu et al., 2000). In such a scheme, the full influent flow (after primary settling) is discharged to the anaerobic reactor of the BEPRAS system, after which the activated sludge is separated from the water by internal settling tanks. The clarified supernatant is pumped to the trickling filter for nitrification and the activated sludge to the anoxic reactor of the BEPRAS system, where the nitrified water rejoins the main BEPRAS system. This external nitrification BEPRAS system has several advantages over continuing to use the trickling filters for organics removal and nitrification, such as significantly reduced oxygen demand (~50%) and biological N and P removal on the full wastewater flow. To date full-scale studies in South Africa have been performed only with rock media trickling filters, for example that at Daspoort WWTP (Muller et al., 2004, 2006a, b). This report describes an investigation on the full-scale operation of a plastic media nitrifying trickling filter (NTF) at the 1 Ml/d Citrusdal WWTP.

The objective of this study is to remove turbidity originating from algae present in oxidation ponds effluents by an easy and inexpensive method. For this reason, a novel lab-scale Step Feed Dual Treatment (SFDT) process was constructed and the efficiency of trickling filter (TF) to remove algae and organic matter was investigated. SFDT process developed in this study is the unique, inexpensive and new system to scavenge algae from oxidation pond effluents. In this system, influent is first treated in a stabilization pond, and subsequently they directed to a TF, so as to provide a dual treatment. Moreover, some fraction of the raw influent was directly sent to TF to maintain a steady biofilm on the TF medium. Stabilization pond was not simulated in the experimental set-up as the main objective of the study is to observe TF ability to scavenge algae from pond effluent. To determine the magnitude of the effect of individual operational parameters (hydraulic loading rate, influent COD and chlorophyll-a concentration) and of their combinations on organics and particle removal efficacy an experimental design was followed. Experiments consistent with twolevel factorial design with three variables (23) were performed. Hydraulic loading rate (HLR) (0.5-2 m3/m2.day), influent COD (150-550 mg/l) and influent chlorophyll-a concentrations (Chl-a) (250-600 µ
g/l) were selected as independent variables. The COD and algae removal (as Chl-a) were selected as dependent variables. Data obtained from the experiments showed that when HLR (m3/m2.day) was increased from 0.5 to 2, Chl-a, NTU, SS and COD removals were decreased, however, more than 85 % removal was attained in each case, except for COD. The lowest removal efficiencies were obtained for all the quality parameters when hydraulic loading was increased to 4 m3/m2.day. It was observed that in general removal percentages for turbidity, Chl-a, SS and COD increased considerably with the decreasing hydraulic loading rate. Highest removals were obtained at lowest HLR. The removal of algae in TF was presumably due to both flocculation (due to algal and bacterial EPS production) and degradation (through bacterial activity) of algae. In conclusion, trickling filter produced clear effluents, with less than 2 NTU, for most of the cases.

The feasibility of using bench-scale biotrickling filter reactors inoculated with the fungus UBAF004, isolated from soil in Tahuapalca, for treatment of water contaminated with cypermethrin was investigated. Wood chips, gravel and ceramics were tested as packing materials for the reactors in batch experiments in small glass flasks. Wood proved to be the material on which the fungus grew best and was thus chosen as the packing material for the reactors. It was determined that UBAF004 had quite low competitive strength compared to other microorganisms when growing on wood and gravel but not necessarily on ceramics. UBAF004 grew slowly in the reactors leading to poor degradation performance. The results obtained indicate that it will be challenging to use UBAF004 for treatment of water contaminated with cypermethrin in Tahuapalca. The single largest issue is to find a way to establish a stable population of the fungus in the reactor and to protect it from being out competed by other microorganisms.

Opponent: Veronika Granat

The kiln drying of wood produces huge amounts of vapour. The vapour is released to the environment when the process purges some of the saturated hot air. The main environmental issue regarding the use of kiln drying process are the release of the water vapour which contains organic contaminants. Some of them are hazardous to human health. In addition, there are some wood particles which may released with the water vapour purging process. In this research, the vapour is condensed and analysed for its organic contaminants and their biodegradability. The result showed that the dominant contaminants present in the condensate were ethanol and methanol with the concentration of approximately 65 mg/L and 25 mg/L respectively. The average COD concentration of the condensate was 159 ± 40 mg/L. The analysis also showed that the contaminants were biodegradable. In order to treat the wastewater, a trickling filter process using bark chips as a support medium was used to treat an artificial wastewater. The artificial wastewater contained the dominant contaminant present in the wood drying condensate. In the experiment, different sizes of bark chips were used. In addition, the loading rate of the treatment system was varied by changing the flow rate and contaminant concentration. The 30 cm long trickling filter using bark chips varying between of 2.8 – 4 mm diameter as the support medium gave a maximum removal of 36.4 % with removal capacity of 8.34 kg COD/m³bed•day at a flow rate of 2.8 cm/min and average inlet COD load of 20.4 kg COD/m3bed•day. The trickling filter with bark chips varying between 5.6 – 8 mm diameter as the support medium was operated using variations in contaminant concentration and flow rate. The operation using different inlet concentration gave the highest removal rate of 13.5 kg COD/m3bed•day at average initial load of 84.9 kg COD/m³bed•day, flow rate of 2.8 cm/min and theoretical initial concentration of 680 mg/L. The trickling filter operated with flow rate variation showed the highest removal rate of 10 kg COD/m³bed•day at an average inlet load of 53.3 kg COD/m³bed•day and flow rate of 7.1 cm/min. The removal rate of the contaminants in treatment was limited. There is a number of possible explanations. First is the active surface area, which indicating the area where the contact between the biofilm surface and feed happened. The active surface area increased as the flow rate increased. Second is the residence time of the feed in the bed. The residence time of the feed varied with the flow rate. It decreased as the flow rate increased. Third is the influence of the contaminants in the feed. The presence of methanol and methanol in the feed inhibited each other’s degradation. The dimention of a full-scale biotrickling filter to be used in actual kiln was also estimated. The estimation was made based on the maximum removal rate and optimum flow rate obtained in the experiments. The result of the estimation showed to obtain significant removal, the required bed would have to be 2.35 m in diameter and 160 in height.

Water pollution has become a global issue with impacts in all countries but particularly those undergoing rapid urbanisation such as China. The review for this thesis established that in 2015 China had 3,910 urban treatment plants with daily treatment capacity of 167million cubic metres. This treatment capacity was able to serve more than 90% of the population in urban regions. Compared to the previous 20 years, these treatment facilities represented a major improvement. However, the thesis uses recent annual environmental reports to show that this level of treatment is still not enough to avoid serious water pollution, more than 30% of Chinese rivers were classified as polluted. The main reason for this it is suggested is that most of treatment infrastructure is for urban areas and the rural areas still lack even basic treatment and rural communities represents about half the total Chinese population. The statistics reported in Chapter 2.1 indicates only 25.3% of towns and 11% of villages are connected to treatment facilities. It was concluded that this lower treatment rate was the major factor impacting on the water environment. Therefore, it is important to improve treatment infrastructure in China remote areas. The literature suggested that trickling filter (TF) technology had advantages as wastewater treatment in this type of situation namely Chinese rural areas. This thesis therefore reports on research to upgrade the TF basic processes to remove newly prioritized nutrient pollutants using novel, sustainable and easily available local media, these were; zeolite, maifan stone, recycled concrete aggregate (RCA), brick, blast furnace slag and dolomite. The media were screened using simple absorption tests first focussing on P removal and then a short-listed group tested under dynamic pilot scale. Further static experiments were carried out on this group to understand the mechanisms involved. The pilot tests used the selected concrete and brick. The best performers against traditional media controls and the results showed pollutant removal (COD, TSS, Turbidity, TOC and N) in line with previous models. The media, except concrete, however released phosphorus. This was further confirmed by batch tests with different operating conditions which found the media released P when the initial P concentration was below 10mg/l or above 15mg/l. Concrete was not affected and continued to adsorb P under all conditions (Chapter 4). It was recommended that tests using crushed concrete for tertiary treatment be carried out. Concrete was further studies by isotherm models the best fit was the Langmuir equation with a maximum adsorption of 6.88mg/g. The mechanism of adsorption was ionic attraction determined by kinetic study and thermodynamic models. The adsorption capacity was compared with other literature, and the results from this study suggested a larger size of crushed concrete (2-5mm) could be used for P removal as effectively as smaller sizes. In order to determine the phase of the P adsorbed, sequential extractions were carried out. The results confirmed labile or easily removed P (LBP) dominated (44%) followed by refractory or occluded P (O-P), Ca-P, Mg-P and Al-P. The literature, suggested LBP would be easily available to plants and the RCA could be reused for plant nutrient supply. Different grades of RCA in terms of their original water to cement ratio (W/C) were also tested for P removal. The study showed high W/C ratio removed more P due to the greater porosity and larger pore sizes than the lower W/C ratio.

The absence of water catchment protection often results in contamination of drinking water supplies. Waters in South East Asia have been exploited to support extensive agriculture, industry, power generation, public water supply, fisheries and recreation use. Ammonia has been identified as a significant contaminant of drinking water because of its ability to affect the disinfection efficiency of chlorine. The interference of ammonia with chlorination is a prevalent and expensive problem faced by many water treatment plants (WTPs) located throughout South East Asia. The conventional approach for ammonia removal was to pre-chlorinate using high concentrations of chlorine, which has a number of disadvantages including the formation of disinfection by-products and high chlorine consumption. This thesis investigated the application of high rate nitrifying trickling filters (NTFs) as a means of ammonia removal from a polluted lowland water source as an alternative to pre-chlorination. NTFs are widely used for the biological remediation of ammonia rich wastewater, however their performance when required to operate under low ammonia concentrations for potable water applications was unknown. A NTF pilot facility consisting of one large-scale, and three small-scale NTFs were constructed at Hope Valley WTP in South Australia. The NTFs were operated to simulate the raw water quality of a polluted catchment identified in Indonesia (Buaran WTP), including variations in ammonia, biological oxygen demand (BOD5), and turbidity. Results confirmed that plastic-packed NTFs were able to operate equally successfully under low ammonia-N concentrations, some 10- to 50-fold lower that that of conventional wastewater applications, where complete conversion of ammonia to nitrate was consistently observed under these markedly reduced loadings. Results also showed that when operated under mass loads equivalent to typical ammonia loading criteria for wastewater NTFs, by increasing hydraulic flow¬, comparable apparent nitrification rates were achieved. These results confirmed that mass transport limitations posed by low ammonia-N concentrations on overall filter performance were insignificant. This thesis also investigated the impact of organic carbon quantity and biodegradability on the nitrification behaviour of the pilot NTF. Results demonstrated that organic carbon loading, rather than the C:N ratio, was an important regulator of filter nitrification capacity, where a linear decline in nitrification performance correlated well with sucrose and methanol augmented carbon loads. Extensive monitoring of inorganic nitrogen species down the NTF, to profile nitrification behaviour, showed sucrose-induced carbon loads greater than 870 mg sBOD5 m–2 d–1 severely suppressed nitrification throughout the entire filter bed. This study also confirmed that critical carbon loads for nitrification varied among carbon sources. In contrast to sucrose, when a more native-like carbon source was dosed (organic fertiliser), no significant decline in nitrification capacity was observed. This could be attributed to differences in carbon biodegradability. This research has provided new insights into the microbial ecology of a potable water NTF. The combination of fluorescent in situ hybridisation (FISH) and scanning electron microscopy (SEM) for in situ analysis of biofilms was successful in identifying the spatial distribution of ammonia oxidising bacteria (AOB), nitrite oxidising bacteria (NOB) and heterotrophs. When the NTF was operated under low organic loads, clusters of AOB and NOB were abundant, and were located in close proximity to each other. Uniquely, the study identified not only Nitrospira spp but also the less common Nitrobacter spp within the NTF biofilm. Biofilm analysis showed that the type of carbon source also strongly influenced the biofilms characteristics in terms of biomass ecology, morphology, and polysaccharide composition, which was correlated with NTF performance. Results showed that an increase in sBOD5 via the addition of sucrose promoted the rapid growth of filamentous heterotrophic bacteria and production of large amounts of polysaccharide. Stratification of nitrifiers and heterotrophs, and high biofilm polysaccharide concentrations were observed at all filter bed depths, which coincided with the impediment of nitrification throughout the entire filter column. High biofilm polysaccharide concentrations also coincided with a significant increase (40 %) in filter hydraulic retention time, as determined by hydraulic tracer experiments. In contrast to sucrose-fed biofilms, organic fertiliser-fed biofilms had a more uniform and dense ultra-structure dominated by many rod shaped bacteria, and was significantly lower in polysaccharide composition. This observation was coupled with superior nitrification performance. This study confirmed that a well functioning NTF is a viable, low cost alternative for ammonia removal from source water abstracted from poorly protected catchments found in many developing countries. Pre-treatment using NTFs has the potential to reduce the chlorine dose required for pre-chlorination. Thereby improving water quality by minimising the formation of disinfection by-products, and improving the control of chlorination. NTFs could also find ready application in other situations where ammonia interferes with chlorine disinfection.

Biofiltraciniai įrenginiai - tai alternatyva standartiniams veikliojo dumblo valymo įrenginiams. Tinkamai įrengus ir naudojant šiuos filtrus galima ženkliai sumažinti eksploatacijos išlaidas bei pasiekti pageidaujamų išvalymo kokybės rezultatų. Biofiltrų efektyvumas labai priklauso nuo naudojamo užpildo tipo, todėl šiame darbe buvo nagrinėjama naujo užpildo nuotekų biofiltracijai tinkamumas. Atlikti tyrimai parodė, kad pasirinkti akmens vatos užpildai yra tinkami naudoti laistomuosiuose filtruose ir juose gali vykti organinių medžiagų šalinimas ir nitrifikacija. Organinių medžiagų šalinimo efektyvumas pagal BDS7 abiejuose filtruose siekė daugiau nei 95 %, o ištekančių nuotekų koncentracija neviršijo 5 mg O2/l. Pirmajame filtre, kuriame buvo naudojama specialiai apdorota akmens vata, skirta augalams auginti, vidutinis nitrifikacijos efektyvumas siekė 62,2 %, antrajame filtre, kuriame buvo naudojama statybinė priešvėjinė akmens vata, skirta pastatams apšiltinti, vidutinis nitrifikacijos efektyvumas buvo 61,6 %. Darbą sudaro šios dalys: įvadas, literatūros analizė, tiriamojo darbo metodika, tyrimų rezultatai, išvados, rekomendacijos, literatūros sąrašas bei priedai. Darbo apimtis – 64 p. teksto be priedų, 17 lent., 25 pav., 46 bibliografiniai šaltiniai. Atskirai pridedami 6 priedai.
Biofilters are an alternative for standard active sludge treatment plants. When used and installed properly, biofilters can significantly reduce operating costs and achieve the desirable cleaning quality results. The effectiveness of biofilters depends on the type of media used, so this paper discuses the suitability of new media for waste water biofiltration. Studies have shown that chosen stone wool media is suitable to use for trickling filters and it may also be used in organic matter removal and nitrification processes. In trickling filters, organic matter removal efficiency by BDS7 was more than 95 %, and wastewater outlet concentration was less than 5 mg O2/l. In the first filter, filled specially with treated stone wool for growing plants, average nitrification efficiency was 62,2 %; while in the second filter, filled with stone wool for buildings thermo isolation, average nitrification efficiency was 61,6 %. Thesis consists of: 64 pages of text without appendixes, 17 tables, 25 pictures, 46 bibliographical entries. Also there are 6 appendixes included.

Discute o pós-tratamento de efluente de lagoas facultativas visando à remoção de nitrogênio amoniacal. Para isso, foram utilizadas unidades terciárias em escala piloto. A escolha do tipo de unidades para o pós-tratamento do efluente levou em consideração a questão do baixo custo e simplicidade de operação. Desta forma, para o estudo, fez-se opção por lagoas rasas e filtros percoladores como unidades de pós-tratamento. O objetivo principal do trabalho foi associar as taxas de aplicação superficial e volumétricas com as remoções de nitrogênio amoniacal nessas unidades. Para lagoas em escala piloto, foram adotadas profundidades de 0,5 m e 1,0 m. As lagoas rasas foram submetidas a diferentes taxas de aplicação e TDH. Para os filtros percoladores, foram escolhidos dois materiais diferentes como meio suporte, pedra britada e anel plástico. Os filtros foram submetidos a diferentes condições operacionais. Para os dois tipos de unidades complementares de tratamento, foram verificados os efeitos das condições ambientais sobre as eficiências de remoção. Na lagoa de 0,5 m foram observadas concentrações de nitrogênio amoniacal abaixo de 20 mg-N/L para tempos de detenção de 5 dias e taxas de aplicação superficial de 50 kgDBO/ha.d. Na lagoa de 1,0 m, concentrações de nitrogênio amoniacal abaixo de 20 mg-N/L só foram possíveis com taxas de aplicação de 50 kgDBO/ha.d e TDH de 10 dias. A lagoa de 0,5 m apresentou uma eficiência maior na remoção de nitrogênio amoniacal do que a lagoa de 1,0 m. Os efluentes dos filtros apresentaram concentrações de nitrogênio amoniacal acima de 20 mg-N/L com taxas acima de 0,20 kgDBO/m³.d. Para taxas de aplicação hidráulica acima de 18 m³/m².d e 0,70 kgDBO/m².d houve o encerramento do processo de nitrificação nos filtros. Os valores de pH e as concentrações de NH3 no efluente da lagoa facultativa submeteram os filtros a operar dentro da faixa de inibição da nitratação, devido ao NH3, sendo observadas concentrações significativas de nitrito no seu efluente. Os filtros percoladores não foram adequados como unidades de pós-tratamento de efluente de lagoa. Embora as lagoas rasas não tenham atendido aos aspectos de múltiplas qualidades do efluente, elas foram mais adequadas ao pós-tratamento de efluente de lagoa facultativa do que os filtros percoladores.
This study discusses the post treatment of effluent ponds aiming at removing the ammonia nitrogen. To this end, tertiary units were used in a pilot scale. The choice of units for the post treatment of the effluent took into consideration the issue of low cost and simplicity of operation. Thus, for this study, we chose shallow ponds and trickling filters as post-treatment units. The main objective of this study was to associate the superficial and the volumetric application rates with the removal of ammonia nitrogen of these units. For the ponds on a pilot scale, two depths were adopted: a pond of 0.5 m and another one of 1.0 m depth. The shallow ponds were subjected to different loading rates and HRT. For the trickling filters, two different kinds of materials were chosen as a medium support: crushed stone and plastic ring. The filters were also subjected to different operating conditions. For both types of additional treatment units it was observed the effects of the environmental conditions on the removal efficiencies. In the pond of 0.5 m depth, it was observed concentrations of ammonia nitrogen below 20 mg-N/L for detention times of 5 days and superficial application rates of 50 kgBOD/ha.d. In the pond of 1.0 m depth, concentrations of ammonia nitrogen below 20 mg-N/L were only possible with application rates of 50 kgBOD/ha.d and HRT of 10 days. The 0.5m-depth pond showed a better efficiency in the removal of ammonia nitrogen than then1.0m-depth pond. The filters had concentrations above 20mg-N/L with rates above 0.20 kgBOD/m³.d. For hydraulic application rates above 18m³/m².d and 0.70kgBOD/m².d there was the cessation of the nitrification process in the filters. The pH values and the concentrations of NH3 in the effluent of the facultative pond made the filters operate within the range of inhibition of nitration, due to the NH3, and it was observed significant concentrations of nitrite in the effluent of the filters. The trickling filters were not suitable as units of post-treatment pond effluent. Although the shallow ponds have not met the multiple aspects of quality of the effluent, they were more adequately for facultative pond effluents post-treatment than trickling filters.

This study was designed to investigate, at laboratory and pilot scale, the effects of various loading and climatic factors on the nitrification perfon-nance of four media, and to undertake a comparative assessment of the media. The media used were blast furnace slag and three random plastic media: Flocor RS, Etapak 160 and a new medium, Etapak 210. Laboratory experiments using pure cultures of Nitrosomonas europaea have determined the effect on nitrification of temperature, pH and substrate, BOD and inhibitor concentrations. Optimal values have been resolved for the temperature and pH and half- saturation constants for the substrate and inhibition are calculated for pure culture conditions. The presence of glucose and glutamic acid has been shown to have a beneficial effect on nitrification, although this observation could not be adequately explained. Pilot scale research, conducted over a two year period, has provided an accurate representation of a nitrifying trickling filter by using effluent from Cranfield STW in filters exposed to the full climadc variation. Data obtained from these filters have indicated the superior performance of the blast furnace slag media due mostly to its ability to maintain a large active bacterial Population without excessive accumulation. Results have been used to support or challenge previous publications, and to generate a set of desion curves. Conclusions from this research have been used in the design of a full scale nitrifying trickling filter which has been constructed at Cranfield STW, early data from which are presented.

Studies in Europe, Japan, and North America have reported that wild fish exposed to treated sewage effluents can exhibit significant physiological and reproductive abnormalities consistent with exposure to hormonally active chemicals. The main objective of this research project was to examine the estrogenic and androgenic activity in treated sewage to determine the risk associated with treated sewage discharges in Australia and New Zealand. Several bioassays, including a sheep estrogen receptor and a rainbow trout androgen receptor binding assay, were set up and validated with model compounds. The assays were then used to measure the estrogenic and androgenic activity in sewage samples from 15 municipal sewage treatment plants (STP) utilizing a variety of treatment technologies. Raw sewage samples contained high levels of both estrogenic and androgenic activity, up to 185 ng/L estradiol equivalents (EEq) and up to 9330 ng/L testosterone equivalents (TEq), respectively. Secondary treatment processes such as activated sludge had the greatest impact on removal of biological activity from the wastewater. The estrogenic and androgenic activity in final treated effluents were <1 to 4.2 ng/L EEq and <6.5 to 736 ng/L TEq, respectively. Based on lowest observable effective concentrations reported in the literature, these levels are unlikely to induce biological effects in exposed fish in the short term. To examine potential long-term effects, resident mosquitofish chronically exposed to undiluted treated sewage were sampled. Several morphological biomarkers indicative of endocrine disruption were measured and compared with mosquitofish captured at a reference site. Mosquitofish captured in a constructed wetland for tertiary treatment of secondary treated sewage exhibited morphological differences such as elongated anal fins consistent with exposure to androgenic chemicals, although this effect was not measurable in fish collected at sites further downstream or at any of the other sites. Based on these results, it is unlikely that mosquitofish populations would be significantly affected by exposure to final treated sewage. A reverse transcription real-time polymerase chain reaction (RT-PCR) method to measure the production of a female-specific protein (vitellogenin) mRNA in adult male mosquitofish was developed, and this could be used as a rapid test to detect early changes in individuals exposed to estrogenic activity.

Neste trabalho, a partir da aplicação da teoria de controle ótimo, são estabelecidos sistemas de controle aplicáveis a três importantes sistemas aeróbios de tratamento de esgotos - filtros biológicos, processos de lodos ativados e os processos combinados formados a partir da combinação dos filtros biológicos e lodos ativados. Para a definição dos sistemas de controle são necessários modelos dinâmicos que descrevam o comportamento dos diferentes sistemas de tratamento. Da literatura são obtidos os modelos dinâmicos destinados à descrição do comportamento do processo de lodos ativados; para o filtro biológico, é proposto um modelo combinando à equação de balanço do reator e o modelo de ordem variável, este último destinado ao cálculo do fluxo de substrato para o interior de biofilmes profundos. Os resultados demonstram que, independentemente do sistema de tratamento considerado, os sistemas de controle reduzem substancialmente os tempos de acomodação e os desvios apresentados pelas variáveis de estado em relação as suas condições de equilíbrio. Por fim, função da inviabilidade de monitoramento de todas as variáveis de estado utilizadas para caracterizar os sistemas de tratamento, são propostos, a partir de modelos simplificados, controladores que incorporam a observação de estados. Também neste caso, os controladores estabelecidos permitem melhorar significativamente o desempenho dos sistemas de tratamento de esgotos analisados.
This paper constructs automatic control systems by means of optimal control theory for three different combinations of wastewater treatment units, namely, trickling filter, activated sludge process and a combined process. The dynamic model for the activated sludge process available in literature and a model proposed for the trickling filter were used in the construction of control systems. It is shown that the controls obtained in this study substantially reduce the durations necessary for the reestablishment of the equilibrium conditions in terms of state variables and the attenuation of oscillations around these conditions. Controls including observers for the state variables were devised on the basis of simplified models for the process in order to deal with the difficulties involved in monitoring all the state variables. These control systems were also found to be quite effective in improving the performance of the wastewater treatment plants considered in this paper.

Dissolved organics in wastewater samples were separated into three size fractions (0-1,000 amu, 1,000-10,000 amu, and 10,000 amu-0.22 m) using ultrafiltration (UF) membranes. The mass distribution within each fraction was adjusted by using a new permeation coefficient model to account for membrane rejection. Dissolved organic and soluble BOD (sBOD) removals in a trickling filter were studied for the different size fractions. The Logan trickling filter model was recalibrated and used to generate predicted removals by size fraction of sBOD, dissolved organic carbon (DOC), and biodegradable DOC (bDOC) for a given influent. Although there was moderate agreement between observed and predicted removals, more investigation is needed to explain shifts in material between different size fractions. Of the three parameters, bDOC may offer a better parameter for modelling trickling filter performance than sBOD.

Com a utilização de filtros percoladores aeróbios, procurou-se promover a remoção de nitrogênio amoniacal do esgoto sanitário efluente de reator anaeróbio compartimentado, através do processo de nitrificação. O trabalho foi desenvolvido em duas fases; na primeira foi realizada a preparação da serragem de couro utilizando-se peneiramento e lavagens e a seguir iniciou-se a aplicação do esgoto sanitário em quatro filtros percoladores. Os filtros F1 e F2 foram operados com a mesma taxa de aplicação (1,91 'M POT.3'/'M POT.2'.dia) e diferentes meios suportes, sendo brita e serragem de couro do tipo wet blue respectivamente. Os filtros F3 e F4 foram preenchidos com serragem de couro e operaram com taxa de aplicação hidráulica de 4,00 e 6,00 'M POT.3'/'M POT.2'.dia . O filtro F3 apresentou melhores eficiências de remoção para todos os parâmetros, com eficiência média de remoção de NTK, 'N'-'NH IND.3' e DQO de 71%; sendo que a partir do sexagésimo quarto dia, esse filtro passou a apresentar 100% de remoção de NTK e 'N'-'NH IND.3'. Os filtros F1 e F2 podem ter tido problemas com a aeração, já que foram operados com menores taxas de aplicação hidráulica e deveriam apresentar melhores resultados. O filtro F4 apresentou baixas eficiências de remoção, provavelmente devido a maior taxa de aplicação hidráulica.
The aim of the work is to promote the ammoniacal nitrogen removal from anaerobic baffed reactor effluent using aerobic trickling filters, through the nitrification process. The research was developed in two phases; firstly the leather sawing was prepared through sieving and washing, later the domestic sewage was applied into four tricking filters. The F1 and F2 filters were operated with the same hydraulic loading (1,91 'M POT.3'/'M POT.2'.day) and different filter packing. For the F1 filter was used rock and for the F2 wet blue leather sawing. The F3 and F4 filters were filled with leather sawing and operated in a hydraulic loading of 4,00 and 6,00 'M POT.3'/'M POT.2'.day respectively. The F3 filter presented better removal efficiencies for all the parameters, with 70% of average removal efficiency of KTN (Kjeldahl Total Nitrogen), 'NH IND.3'-'N' (ammoniacal nitrogen) and COD (Chemical Oxygen Demand). From the 49th day on, this filter presented 100% of removal efficiency of KTN and 'NH IND.3'-'N'. The F1 and F2 filter were supposed to present better results due to the lower hydraulic loading, but it did not happen, probably because the aeration was not enough. The F4 filter presented low removal efficiency, possibly due to the higher hydraulic loading.

L'objectif principal de ce travail de thèse concerne l'étude de l' élimination de la DCO et de la nitrification dans une nouveau lit bactérien Multi-Section ( MSB ) . Après une caractérisation de l’hydrodynamique et du transfert d’oxygène de ce lit bactérien, les expériences biologiques menées sous des conditions opératoires contrastées (fortes et faibles charges organiques eteaux usées contenant ou pas des matières particulairs) ont été menées. En parallèle, des simulations avec le logiciel Biowin® ont été réalisées. Les principaux résultats sont résumés en suivant :- La rétention de liquide statique est majoritaire par rapport à la rétention dynamique que ce soit en présence ou en absence de biofilm. Le biofilm joue le rôle d’une "éponge" permettant un maintien de l’humidité du lit même à faible débit. Les expériences de DTS ont montré que le biofilm accroit le temps de séjour du liquide et conduit à une diminution de l’épaisseur du film liquide permettant ainsi de promouvoir le transfert de l'oxygène.- Le réacteur MSB montre une élimination efficace de la DCO (> 95 % ) et de la nitrification ( > 60 % de l’azote entrant), mais une accumulation de DCO particulaire a lieu dans le filtre ce qui conduira à un colmatage à terme. La nitrification cohabite avecl’élimination de la DCO même dans la première section et pour une charge organique élevée ce qui implique une bonne capacité d’oxygénation du MSB par l’aération naturelle.- Un modèle dynamique de MSB a été utilisé implémenté sur le simulateur - BioWin , afin d'obtenir la répartition des biomasses au sein du réacteur et d'évaluer le processus limitant dans chaque section. Le modèle partiellement calibré peut aider à estimer les besoins minimum d'oxygène pour la nitrification et peut rendre compte de la compétition entre la croissance hétérotrophe et la nitrification
The main objective of this PhD work focused on the study of the COD removal and nitrification in a new designed Multi-Section Bioreactor (MSB). Hydrodynamic characterization of the reactor, biological experiments under contrasted conditions and simulations by Biowin® software were carried out:- Firstly, it was found that static liquid retention is the predominant part both without and with the presence of biofilm. Biofilm acts like a "sponge". RTD experiments showed that biofilm can promote liquid residence time, decrease the liquid film andpromote the oxygen transfer consequently.- Secondly, the MSB operated at contrasted organic loading rate (OLRs) and nitrogen loading rate (NLRs) showed that COD can be effectively removed (removal efficiency > 95%) and nitrification (> 60% of the N removal) occurred in this biofilter.Nitrification is efficient even in the first section implying no drastic oxygen limitation though only natural aeration is occurring.- Thirdly, a TF dynamic model has been used from a simulator - BioWin, in order to get more insights on the biomass distribution in the pilot and to assess the limiting process in each section of the bioreactor. Calibration of the model can help us to estimate theminimum oxygen requirement for nitrification for each zone inside the pilot and it can well represent the competition between heterotrophic growth and nitrification

Com a crescente ideia de sustentabilidade, surge a necessidade de utilização de recursos renováveis e reaproveitamento de resíduos gerados em processos industriais. Neste trabalho foi avaliada a utilização da cinza pesada oriunda da queima do carvão em usinas termoelétricas no desenvolvimento de um Cermet. O compósito Cinza-Ferro (Cz-10Fe) foi obtido por metalurgia do pó e é composto de cinza pesada moída com adição de 10% em massa de pó de ferro puro. A adição do ferro é justificada para melhoria das propriedades mecânicas do material cerâmico. O compósito foi aplicado como meio suporte para biofilme em filtro biológico percolador, no pós-tratamento de efluentes domésticos. Foram realizados estudos com os principais componentes da cinza, tais como a sílica (SiO2), em forma de pó de quartzo, e a alumina (Al2O3) na versão comercial para avaliação da interação dos mesmos com o ferro e avaliação de suas propriedades mecânicas sob influência da variação da temperatura de sinterização A cinza pesada, obtida na Usina Tractebel de Charqueadas, foi moída durante 2, 4 e 8 horas para determinação do tamanho de partícula ideal para o compósito. Após caracterização, foi selecionada cinza moída por 2 horas para a produção dos compósitos para aplicação. A aplicação se deu utilizando um protótipo no pós-tratamento de efluentes da Estação de Tratamento de Esgotos (ETE) da COMUSA visando a remoção de Demanda Química de Oxigênio (DQO). Obteve-se incremento na eficiência do processo, reduzindo a DQO do efluente final em média 9%, indicando a viabilidade de uso do protótipo no pós- tratamento de esgotos domésticos, com porosidade aproximada de 20%, obtidos na cinza moída por 2 horas e sinterizado com ferro, como meio suporte para biofilme em filtro biológico percolador.
With the crescent idea of sustainability, there is a necessity for the use of renewable resources and the reuse of waste generated in industrial processes. In this work the use of the coal bottom ash from thermoelectric plants was evaluated in the development of a Cermet. The composite Ash-Iron (Cz-10Fe) was obtained by powder metallurgy and is composed of ground heavy ash with addition of 10% by mass of pure iron powder. The addition of iron is justified to improve the mechanical properties of the ceramic material. The composite was applied as biofilm packing media in trickling filter in the post-treatment of domestic effluents. Studies with the main components of the ash, such as silica (SiO2), in the form of quartz powder, and alumina (Al2O3) in the commercial version were carried out to evaluate their interaction with iron and evaluation of their mechanical properties under influence of the sintering temperature variation The bottom ash obtained at Tractebel from Charqueadas was milling for 2, 4 and 8 hours to determine the ideal particle size for the composite. After characterization, milled ash for 2 hours was selected for the production of the composites for application. The application was done using a prototype in the post-treatment of effluents from the Wastewater Treatment Station (ETE) of COMUSA aiming at the removal of Chemical Oxygen Demand (COD). The efficiency of the process was obtained by reducing the COD of the final effluent by a mean of 9%, indicating the viability of the utilization the prototype in the post-treatment of domestic sewage, with approximate porosity of 20%, obtained in ground ash for 2 hours and sintered with iron powder, in biofilm packing media in trickling filter.

Neste trabalho, estudou-se a utilização de filtros percoladores como tratamento complementar de efluente de lagoa de estabilização visando a remoção de nitrogênio, principal causador de problemas como a eutrofização de corpos hídricos em conjunto com o fósforo. A motivação principal para o desenvolvimento desta pesquisa foi a dificuldade encontrada para o atendimento ao padrão definido pela Resolução CONAMA 357/05, a qual define concentração máxima de nitrogênio para lançamento de efluentes em corpos hídricos receptores de 20 mg/l. Em 2008 foi promulgada a Resolução CONAMA nº 397 a qual estabeleceu, em seu Artigo 34, que o padrão de emissão de nitrogênio amoniacal seria suspenso temporariamente para efluentes de estação de tratamento de esgoto sanitário, continuando a valer a concentração máxima nos corpos receptores estabelecidas na Resolução CONAMA 357/05. Sendo assim, a questão sobre a remoção de nutrientes constitui uma preocupação diretamente relacionada ao emprego dos sistemas de lagoas de estabilização. Para esta pesquisa, utilizou-se os efluentes tratados por lagoas facultativas provenientes da Estação de Tratamento de Esgoto do município de Lins/SP e, para o experimento em questão, foram construídos dois filtros biológicos seguidos de decantadores, ambos em escala piloto. Os filtros foram construídos em um corpo cilíndrico de polipropileno com diâmetro de 1,2 metros e teve seu volume dividido igualmente por uma placa vertical também de polipropileno, propiciando área superficial de 1,13 m² e volume útil total de 4,52m³. Para o fornecimento de oxigênio, indispensável para o processo de nitrificação, o filtro foi apoiado sobre uma base de concreto com drenos de fundo para permitir a ventilação do sistema, garantindo a concentração de oxigênio necessária. Para comparação da eficiência na remoção do nitrogênio, cada filtro foi preenchido com determinado tipo de material, ou seja, um filtro continha pedra britada variando de 4 a 8, admitindo-se área superficial de 70 m²/m³ e possibilitando uma área para formação de biofilme de 316,7 m², enquanto que no outro filtro foram utilizado anéis plásticos com área superficial de 100m³/m³, fornecendo 542,9 m² de área superficial para a formação de biofilme. Também foram construídos decantadores após os filtros percoladores para a remoção dos sólidos em suspensão, não sendo alvo da pesquisa em questão Tendo em vista que o molhamento de todo o material de preenchimento se faz importante para a eficiência do sistema, foi utilizado um sistema de recalque para o transporte do esgoto para o filtro, distribuído continuamente sobre o meio suporte e com vazão divida igualmente para os dois filtros por meio de um sistema de distribuição de pvc perfurado com diâmetro de 40 mm e com funcionamento semelhante a um aspersor de jardim A taxa de aplicação superficial variou entre baixa, intermediária e alta, tendo aumento de vazão no sistema até que o processo de nitrificação cessasse e cada fase teve duração de 180 dias. Conforme verificado nos resultados obtidos, filtros percoladores apresentam boa eficiência na remoção do nitrogênio do efluente, seja pela desnitrificação via nitrito ou pela volatilização do nitrogênio. A ETAPA 1 apresentou resultados bastante satisfatórios para o filtro de brita em relação ao filtro com anéis plásticos, podendo ter sido ocasionado pela área rugosa das britas, a qual facilitou a formação do biofilme, enquanto que a superfície lisa dos anéis plásticos dificulta a formação do biofilme, resultando na baixa eficiência apesar da maior área superficial. Já na ETAPA 3, com taxas de aplicação maiores, o filtro preenchido com anéis plásticos apresentou maior eficiência do que o filtro com brita. Tal fato pode ter sido conseqüência da maior área disponível para a formação do biofilme nos anéis plásticos. Ambos os casos apresentaram eficiência suficiente para remoção de nitrogênio a concentrações inferiores a 20 mg/l. Tais resultados demonstram que os filtros percoladores possuem boa funcionalidade para a remoção do nitrogênio de efluente sanitário tratado por sistemas de lagoas de estabilização.
It was studied in this paper the use of trickling filters as a complementary treatment of wastewater stabilization pond seeking removal of nitrogen, the main cause of problems such as eutrophication of water bodies in conjunction with phosphorus. The main motivation for this research was the difficulty to meet the standard set by CONAMA 357/05 Resolution, which defines the maximum nitrogen concentration for disposal of effluents in water bodies as 20 mg / l. In 2008 was created the CONAMA Resolution 397 which established, in Article 34 that the emission pattern of ammonia nitrogen would be temporarily suspended for wastewater treatment plant discharge, continuing to enforce the maximum concentration in the water bodies established in CONAMA Resolution 357/05. Thus, the question on the removal of nutrients is a concern related to the use of systems of waste stabilization ponds. For this study, was used the treated effluent by anaerobic and facultative ponds from the Sewage Treatment Plant in the city of Lins/SP, and for this experiment was constructed two trickling filters followed by settlers, both in pilot scale. The filters were constructed on a cylindrical body of polypropylene with a diameter of 1.2 meters and its volume was divided symmetrically by a vertical plate also made of polypropylene, providing superficial area of 1.13m² and total net volume of 4.52m³. To supply oxygen, essential for the nitrification process, the filter was supported on a concrete base with bottom drains to allow the ventilation system, to supply the concentration of oxygen needed. To compare the efficiency of nitrogen removal, each filter was filled with a certain type of material, ie, a filter containing crushed rock ranging from 4 to 8, considering surface area of 70m²/m³ and a possible area for biofilm formation of 316.7m², while in the other filter was used plastic rings with surface area of 100m²/m³, providing 542.9m² of surface area for biofilm formation. Settlers were constructed after the trickling filters for the removal of suspended solids, because that are not the focus of this research. Considering that the wetness around the filling material is important for system efficiency, it was used a pumping system to transport sewage to the filter, continuously distributed on the support materials and flow split equally for both filters by a distribution system made of perforated PVC with a diameter of 40mm and functioning like a garden sprinkler. The application rate surface ranged from low, intermediate and high, having increased flow in the system until the process of nitrification ended and each phase lasted 180 days. As shown in the results, trickling filters show good efficiency in removing nitrogen from wastewater, either by denitrification by nitrite or by the volatilization of nitrogen. The STEP 1 showed satisfactory results for the filter of crushed rocks over the filter with plastic rings, which may have been caused by the rocks rough area, which facilitated the formation of biofilms, while the smooth surface of the plastic rings makes harder the formation of biofilm, resulting in low efficiency despite the larger surface area. In STEP 3, with higher rates of application, the filter filled with plastic rings showed higher efficiency than the filter with crushed rocks. This might have been a consequence of the greater area available for biofilm formation in plastic rings. Both cases had efficient enough to achieve nitrogen concentrations lower than 20 mg/l. These results demonstrate that the trickling filters have good functionality for removing nitrogen from sanitary wastewater treated systems for waste stabilization ponds.

Nesta tese foi estudada a utilização da serragem de couro do tipo wet blue como meio suporte de filtros percoladores no pós-tratamento de esgoto sanitário. O desenvolvimento deu-se em três fases: na primeira fase foram realizadas a classificação e caracterização da serragem, bem como a sua preparação através de peneiramento, lavagens e secagem. Foram realizados dois tipos de lavagens: uma em batelada com solução alcalina de pH em torno de 9,0 e outra contínua com água corrente com pH em torno de 7,0. Na segunda fase foram utilizados quatro filtros percoladores com volume aproximado de 10 litros; dois foram preenchidos com serragem de couro bruta peneirada e os outros dois com serragem de couro peneirada, lavada e seca ao ar livre. Esses filtros operaram em série com quatro filtros de volume aproximado de 30 litros, preenchidos da mesma forma. Os quatro primeiros filtros receberam o efluente de um reator anaeróbio compartimentado e os demais receberam os efluentes dos primeiros. A terceira fase consistiu do uso apenas dos filtros percoladores de maiores volumes, os quais operaram aerados e com o afluente alcalinizado. Os conjuntos de filtros que operaram em série na segunda fase apresentaram eficiências de remoção de coliformes totais e fecais que variaram em torno de 94 e 92%, respectivamente. A eficiência de remoção de DBO5 total foi cerca de 80%. Na terceira fase, os filtros apresentaram eficiências de remoção de coliformes totais e fecais de cerca de 98 e 99%, respectivamente. Com relação à eficiência de remoção de DBO5, o valor encontrado foi de aproximadamente 80%. Nesta terceira fase foram encontradas excelentes reduções de NTK e de nitrogênio amoniacal com eficiências médias de remoção, para os dois parâmetros, de 83% antes da alcalinização e de 100% após a alcalinização.
This thesis studied the use of leather sawing (wet blue type) as packed bed of trickling filters in the wastewater post-treatment. The thesis was divided into three stages: as first stage the classification and characterization of the leather sawings were accomplished, as well as its conditioning through sieving, washing and drying. Two washing techniques were accomplished: a batch one with alkaline solution of pH around 9,0 and a continuous one with water of pH around 7,0. In the second stage four trickling filters were used with an approximated volume of 10 L; two were filled with sifted raw leather sawing and the two others with sifted, washed and open-air dryed leather sawing. Those filters operated in series with four other filters with an approximated volume of 30 L, filled in the same way. The 10 L filters received the efluent of an anaerobic baffled reactor and the others received the efluents of the first ones. The third stage consisted on the 30 L trickling filters alone, which were aerated and feeded with alkalinized influent. The group of filters that operated in series in the second stage presented total and fecal coliform removal efficiencies that varied around 94 and 92%, respectively. The efficiency of total BOD5 removal was around 80%. In the third stage filters presented total and fecal coliformes removal efficiencies around 98 and 99%, respectively. About BOD5 removal efficiency, it was found a value of approximately 80%. In this stage it was achieved excellent KTN and ammoniacal nitrogen removals with average removal efficiencies of 83% before alkalinization and 100% after alkalinization.

En 2013, le SIAAP a lancé un programme pour moderniser la station Seine Aval, la plus grande STEP en Europe. Après la modernisation, la configuration de traitement de la station sera complexe. Pour évaluer les impacts économiques et environnementaux des choix d’exploitation et identifier les meilleurs choix en fonction des besoins de traitement, les outils de support, comme les modèles mathématiques des procédés de traitement sont demandés. Cette thèse présente la modélisation de la filière biofiltration de la station Seine Aval après sa modernisation. La filière est composée d’un procédé de décantation primaire, de trois étages de biofiltration et d’un procédé de clarification tertiaire. Une stratégie de modélisation est d’abord proposée. Ensuite, les modèles SimBio et SimDec, qui simulent respectivement le fonctionnement de la biofiltration et de la décantation lamellaire physico-chimique sont améliorés afin de construire les modèles de procédés individuels de la filière. Après la calibration-validation, les modèles sont assemblés afin de construire le modèle de la filière biofiltration. Les règles de commandes et les évaluations des coûts et des impacts environnementaux sont intégrées. Enfin, pour évaluer le potentiel d’application du modèle filière comme un outil d’optimisation, des scénarios d’exploitation sont testés et analysés. Selon les résultats, la performance de traitement de chaque procédé modélisé peut être bien prédite par les modèles de procédés individuels. Le modèle de la filière biofiltration construit est capable d’indiquer les avantages et les inconvénients des scénarios d’exploitation et d’aider à identifier le choix d’exploitation optimum
In 2013, SIAAP (the interdepartmental association for sewage disposal for the Paris conurbation) launched a program to upgrade the Seine Aval (SAV) plant, the largest wastewater treatment plant in Europe. This upgrade program, which is scheduled to be finalized in 2022, aims to adapt the plant to the urbanization of the Paris region and to regulatory requirements. After the upgrade, the wastewater treatment will be realized by two parallel treatment lines: (i) the biofiltration line and (ii) the membrane bioreactor line (MBR). The configuration of the treatment after the upgrade of the station will be complex, which provides several local and global operation choices to realize the wastewater treatment. To evaluate the economic and environmental impacts of these operation choices and identify the best choices based on treatment needs, support tools such as models simulating the performance of treatment processes are required. This thesis presents the modelling work for the biofiltration line of the Seine Aval plant after its upgrade in 2022. The modelled line is composed of a primary settling process, three stages of biofiltration and a tertiary clarification process. Considering the progress of the upgrade program, a modelling strategy for the biofiltration line is first proposed. This strategy defines the order of modelling for the treatment steps of the biofiltration line and the control rules to be integrated in the biofiltration line model. Then, the SimBio model and SimDec model, which respectively simulate the treatment performance of biofiltration and physico-chemical settling process, are modified and improved in order to build process models for each treatment step of the biofiltration line. The process models are calibrated and validated with data from the plants of SIAAP. After calibration and validation, the models are connected in order to build the model for the biofiltration line. Control rules and evaluations of treatment costs and environmental impacts are integrated in the biofiltration line model. Finally, to evaluate the potential for using the biofiltration line model as a tool for treatment optimization, several operation scenarios are tested and analysed. According to the results obtained, in general, the performance of each treatment step modelled can be well predicted by the process models. The built biofiltration line model is able to indicate the advantages and disadvantages of the operation scenarios and help to identify the optimum operation choice. It therefore has the potential to be used as a tool to help optimize the biofiltration line of the Seine Aval plant

碩士
國立中山大學
環境工程研究所
100
Because of high intense population is in Taiwan, households water use requires a considerable amount. It is substantially reduce daily water use to share primary water resources, if we can reclaim domestic wastewater properly and make it support. Currently, reclaiming water is an emerging requirement for management and application. If we can adequately monitor and treat reclaimed water, reducing environmental contaminants, costs, and environmental feedback is possible. The study treated domestic wastewater of Feng-Shan river using GAC trickling filter with two column in a series and the removal efficiency of organic carbon was observed. The experimental results indicated that removal efficiency of organic carbon concentration was decreased as the empty-bed contact time (EBCT) increased. The best average removal efficiency of TOC and DOC was about 72% and 78%. According to the TOC removal rates using GAC at different temperatures, the TOC removal rates at room temperature and 4℃were respectively 95% and 90% in the first column of the experiment and 85% and 80% in the second column. The removal rates of dissolved organic carbon (DOC) using GAC folter system at room temperature and 4℃ were respectively 95% and 90% in the first column of the experiment and 90% and 87% in the second column. Obviously,the TOC removal rate treated using GAC filter system at room temperature was superior to that treated at 4℃ In comparing treated water and recycled water,most of the water quality parameters (temperature、Suspended solids、BOD、COD、pH) were to meet recycled water quality standards.However, the system due to use GAC trickling filter system treatment that easily decrease dissolved oxygen in treated water but conductivity in treated water without changes. These two water parameters were failed to meet the recycled water standards. By the way, we found trained GAC through SEM irradiation the biofilm area of trained GAC surface at 25℃was superior to that treated at 4℃. It corresponds to the removal efficiency of organic carbon, the removal efficiency of 25℃ was higher than result of 4℃. Therefore, a certain relationship between the biofilm area and removal efficiency of organic carbon is existed in this work.

A pilot-scale study was undertaken to further the development of a combined trickling filter-activated sludge process designed for biological phosphorus removal and nitrification-denitrification. The system is called the FGR-SGR (fixed growth reactorsuspended growth reactor) process. The innovative aspect of the FGR-SGR process is the incorporation of a fixed growth (trickling filter) component into the conventional suspended growth (activated sludge) biological nutrient removal treatment train. The objective of the study was to extend and optimize design and operational criteria for biological nutrient removal in the FGR-SGR process, including an assessment of optimum process reactor hydraulic retention times, internal recycle flow rates, and operating mixed liquor suspended solids (MISS) concentration. Two pilot-scale processes were operated in parallel, to compare controlled changes in design parameters. Both pilot plants consistently produced an effluent typically containing 10-15 mg/L suspended solids, less than 10 mg/L BOD₅,less than 0.01 mg N/L ammonia, and 2-3 mg N/L total kjeldahl nitrogen, regardless of design and operational changes. Nitrification in the FGRS accounted for greater than 85% of the process total nitrification, and the fixed growth nitrification was found to be first order with respect to ammonia concentration. A higher FGR irrigation (recycle) rate was associated with a significantly greater nitrification rate. On the other hand, phosphorus removal was highly dependent on design and operational changes to the process. Daily short-term increases in the FGR recycle rate to prevent excess solids buildup on the media greatly improved phosphorus removal. With daily pulse hydraulic loading, low effluent orthophosphate concentrations (less than 0.3 mg P/L) were observed when the ratio of the mass of volatile fatty acids (VFA) taken up in the anaerobic reactor to process influent total phosphorus (P) concentration was greater than 6 mg HAc/mg P; at lower ratios, effluent orthophosphate concentrations increased to greater than 1 mg P/L. The mass of volatile fatty acids taken up in the anaerobic reactor depended on the anaerobic actual hydraulic retention time, the steady-state process influent VFA concentration, and the steady-state mean MLSS concentration. Biological phosphorus removal was significantly better at an aeration basin mean MLSS concentration of approximately 3,000 mg/L, compared to one of 2,000 mg/L. Denitrification in the anoxic reactor was accompanied by bacterial uptake of orthophosphate. Phosphorus uptake in the anoxic reactor accounted for approximately 45% of overall process total phosphorus removal. Bench-scale batch tests showed that following the completion of denitrification, secondary phosphorus release occurred for the remainder of the anoxic phase. Allowing significant concentrations of VFA to reach the anoxic reactor induced phosphorus release during the first few minutes of denitrification, reducing net anoxic phosphorus uptake. Bench-scale batch tests designed to simulate the effects of manipulating internal recycle flow rates to dampen hydraulic shocks typically caused by the peak daily load in full-scale plants indicated that manipulation of the recycle flows has the potential to improve phosphorus removal in the process.

碩士
長庚大學
企業管理研究所
97
This project is related to the research on the effectiveness of PCB organic wastewater treatment through trickling filter method. Since PCB organic wastewater is conventionally treated by either activated sludge or contact aerobic basin methods, this project has therefore chosen the trickling filter method which is seldom used in Taiwan and has never been applied for the PCB Industry. After pilot testing as well as the scaled up commercial plant operation, the current daily treatment capacity is approximately 3000 – 4000 tons, and with monthly organic pollutant COD (Chemical Oxygen Demand) of approximately 100-140 tons. The COD concentration of the effluent water has been stably reduced from 120-140 mg/l to 100-120 mg/L range (National Standard is below 120 mg/L) and removal efficiency significantly increased from 75-80% to 80-85%. Apart from stable water quality, most importantly, the treatment cost is relatively lower compared to conventional methods with unit treatment cost reduced from 23.0 NT$/M3 to 21.8 NT $/M3, equivalent to 5.2% margin. The final unit sludge generation quantity was improved by a margin of 31.1% from 0.45 kg/kg-COD to 0.31 kg/kg-COD, moreover, this has further effectively lessened the secondary pollutant problem associated with the subsequent sludge treatment. Consequently, this has imperceptibly reduced the direct penalty loss associated with fines imposed by the Environmental Bureau due to unstable water quality. In addition, it also helps to prevent corporate risk on work stoppage orders originated from the impingement of the Environmental Regulations. This trickling filter method could be used as the corporate reference when setting up similar production plants. Keyword ：Printed Circuit Board , COD (Chemical Oxygen Demand), Trickling Filter, Organic Pollutants.