Download or read book Biodegradation of Selected Organic Nitrogen Compounds in Activated Sludge Systems written by Jia Guo and published by . This book was released on 2010 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: Activated sludge systems are commonly used to remove organic matter and nutrients from wastewater. They are also used to remove synthetic organic compounds from industrial activities. In this study, two identical activated sludge-based continuous stirred tank reactors (CSTRs) were employed to study the biodegradation of melamine and 4-nitrophenol and their impact on wastewater effluent water quality and microbial structure and functions. Two CSTRs at steady-state conditions were fed with two synthetic organic nitrogen compounds, melamine and p-nitrophenol (PNP) for 12 hours on day 136 and 150, respectively, of an extended test. Melamine, although toxic to human and animals, presented no detrimental effect on bioreactor performance and it appeared to act as an inert soluble substance in the activated sludge system. After the shock loading, melamine was quickly washed out of the continuous flow system. Batch degradation studies confirmed that the activated sludge from the CSTR was not capable of degrading melamine. The other chemical p-nitrophenol (PNP), however, showed significant toxicity towards the activated sludge, although subpeaks of possible PNP degradation metabolites were detected by high performance liquid chromatography indicating that the PNP could be partially degradable by the activated sludge. After 12-h shock loading of PNP, significant inhibition of nitrification and bacterial activity by PNP resulted in a prolonged period (> 22 days) of deterioration of effluent water quality. The results indicate that the fate and toxicity of synthetic organic nitrogen compounds can be quite different in activated sludge systems, although both melamine and PNP increased total nitrogen concentrations in wastewater effluent.

Download or read book Biodegradation and Treatability of Specific Pollutants written by Edwin F. Barth and published by . This book was released on 1979 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Soluble Organic Nitrogen Characteristics and Removal written by Stephen J. Randtke and published by . This book was released on 1978 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Selected Biodegradation Techniques for Treatment And or Ultimate Disposal of Organic Materials written by SCS Engineers and published by . This book was released on 1979 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigations of Biodegradability and Toxicity of Organic Compounds written by Jan Dojlido and published by . This book was released on 1979 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1991 with total page 884 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1991 with total page 1354 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development and Calibration of Bio kinetic Models for Organic Carbon and Nitrogen Biodegradation in an Aerobic Activated Sludge System written by Muhammad Azizul Hoque and published by . This book was released on 2010 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: Substrate removal mechanisms in a mixed culture of an activated sludge system are still a mystery that researchers have been trying to unravel by proposing and developing models to interpret the observed experimental data. Activated Sludge Model Number 1 (ASM1) was first introduced to better understand the biochemical mechanisms during carbon and nitrogen oxidation and was based on the assumption that the external substrate is consumed only for biomass growth. This model ignored the formation of intracellular polymers (storage products) in the biomass cell, though several researchers observed the phenomenon of storage of carbon sources and the significant role it played in the carbon removal process. As a consequence, the Activated Sludge Model Number 3 (ASM3) was formulated assuming that all the easily biodegradable substrate is first stored internally during the feast phase before being used for growth during famine conditions. However, experimental observations proved that both storage and growth occur simultaneously during the feast phase. Consequently, the simultaneous storage and growth (SSAG) model was developed as an extension to ASM3 specifically to gain an in-depth understanding of the carbon oxidation process. While considerable investigation has been focused on model calibration using respirometric measurements of the oxygen uptake rate (OUR) during the aerobic biodegradation of substrate, model-based interpretation of titrimetric measurements has been limited. In biological systems, the oxygen consumption and corresponding pH changes occur simultaneously and can be easily monitored using respirometric and titrimetric experimental observations respectively. Attempts were, therefore, made to calibrate ASM1 using titrimetric measurements. During the subsequent successful development, consideration was given to the pH effects of carbon uptake, ammonia uptake for growth, CO2 production from carbon metabolism and the nonlinear carbon dioxide transfer rate (CTR) due to stripping. While respirometry was successfully used to calibrate every proposed new model, the interpretation of titrimetric measurements, however, was always based on ASM1, using calibration substrates such as acetate and ammonium. The SSAG model, developed in the year 2005, proposed an improved kinetic expression for the degradation of storage products under famine conditions. It was successfully calibrated using on-line respirometric measurements and validated using off-line storage products measurements with acetate used as a calibration substrate. However it failed to explain the titrimetric behavior of the substrate biodegradation process. While in most cases the above models were calibrated using simple synthetic substrates, the application of these models for complex substrates was not investigated. Therefore, in this dissertation, the biodegradation kinetics for different substrates like acetate (simple carbon source), sodium dodecyl sulfate (relatively complex carbon source), ammonium (simple nitrogen source), urea (relatively complex nitrogen source) and glutamic acid (combination of carbon and nitrogen) were investigated. A titrimetric respirometer, established in the Water-waste laboratory in the Faculty of Engineering and Surveying, University of Southern Queensland, Australia, was used to conduct batch experiments in order to monitor substrate biodegradation process in an aerobic activated sludge system. Both the dissolved oxygen and the pH control data were logged with the Labview software package. A spreadsheet program was used to calculate the oxygen uptake rate and the proton production/consumption rate from the raw measurements. During batch experiments, the biodegradation of all five test substrates showed unique respirometric and titrimetric behaviors indicating that each of these compounds is biodegraded using distinctive mechanisms with the involvement and coordination of different bacterial populations. The pattern of OURs were observed varying from substrate to substrate describing the characteristics of test compounds. The titrimetric profiles were also different for different substrates biodegradation reflecting the on-going biochemical reaction of respective substrate in activated sludge system. While acetate biodegradation, for example, caused proton consumption (at pH 7.8) in the liquid medium, proton production was noted under feast conditions when either sodium dodecyl sulfate or glutamic acid was used as a test substrate. An in-depth revision of the existing activated sludge models was completed and the models were assessed using experimental observations. An improved bio-kinetic model which includes both the oxygen and proton balances for the biodegradation of each of the test substrates was then developed. In addition, the substrates biodegradation pathway and the non-linear CO2 transfer process were considered during the modeling. For proper model evaluation, the proposed model was calibrated using varying initial substrate concentrations and pH levels. In addition, three different calibration approaches: using respirometric measurements alone, using titrimetric measurements alone and using combined respirometric-titrimetric measurements, were applied during the study. The estimation of model parameters was undertaken using non-linear techniques utilizing the algorithms in the optimisation toolbox (MATLAB). For the biodegradation of each test substrate, the proposed model was successfully calibrated using both the respirometric and titrimetric behaviors in the activated sludge system. The estimated model parameters showed consistent results for all three calibration approaches thereby confirming the precision of the proposed model. The parameter estimation errors (calculated for 95% confidence intervals) as well as the mean squared errors for the different calibration approaches were quite reasonable and confirmed the statistical soundness of the proposed model. In addition, the proposed model was validated using off-line measurements. This dissertation presents an in-depth explanation of how the proposed models interpret the biodegradation processes and how the model parameters vary for different substrates in an activated sludge system. The results will be helpful in further refining current models that can contribute to the optimization of the design operation and enhanced performance of full scale wastewater treatment plants.

Download or read book Nitrification and Denitrification in the Activated Sludge Process written by Michael H. Gerardi and published by John Wiley & Sons. This book was released on 2003-03-19 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrification and Denitrification in the Activated Sludge Process, the first in a series on the microbiology of wastewater treatment, comprises the critical topics of cost-effective operation, permit compliance, process control, and troubleshooting in wastewater treatment plants. Avoiding the technical jargon, chemical equations, and kinetics that typically accompany such texts, Nitrification and Denitrification in the Activated Sludge Process directly addresses plant operators and technicians, providing necessary information for understanding the microbiology and biological conditions that occur in the treatment process. Of special interest to wastewater treatment plant operators are the bacteria that degrade nitrogenous wastes–the nitrifying bacteria–and the bacteria that degrade carbonaceous wastes–the cBOD-removing bacteria. Both groups of bacteria need to be routinely monitored and operational conditions favorably adjusted to ensure desired nitrification. Each chapter in this groundbreaking study offers a better understanding of the importance of nitrification and denitrification and the bacteria involved in these crucial processes. Chapters include: Organotrophs The Wastewater Nitrogen Cycle Nitrite Ion Accumulation Dissolved Oxygen Denitrifying Bacteria Gaseous End Products Free Molecular Oxygen The Occurrence of Denitrification

Download or read book Water Resources Research Catalog written by and published by . This book was released on 1966 with total page 1464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microbial Community Analysis written by Thomas E. Cloete and published by IWA Publishing. This book was released on 1997-01-01 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microbial Community Analysis surveys the vast amount of theoretical and practical knowledge on the design of biological treatment systems. It describes the different types of biological wastewater systems, the role of microbial diversity in these systems, and how this affects design and operation, methods for studying microbial community dynamics, and mathematical modelling of these systems. Contents Biological methods for the treatment of wastewaters Biodiversity and microbial interactions in the biodegradation of organic compounds Microbial population dynamics in biological wastewater treatment plants Molecular techniques for determining microbial community structures in activated sludge Principles in the modelling of biological wastewater treatment plants Practical considerations for the design of biological wastewater treatment systems Scientific and Technical Report No.5

Download or read book Factors Influencing the Biodegradation Kinetics of Toxic Organic Compounds in Activated Sludge Systems written by Charles Vijay Anselm and published by . This book was released on 1998 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: When phenol was removed from the feed stream the measured kinetic parameters for phenol significantly reduced, and the kinetic parameters for 4CP increased. When both compounds were removed from the feed the measured kinetic parameters for phenol and 4CP reduced significantly. The results observed from this research have shown that rate of biodegradation of individual organic compounds is significantly influenced by changes in operational conditions. The findings of this research is a significant contribution towards the understanding of the factors that affect the rate of biodegradation kinetics of toxic organic compounds in activated sludge treatment systems.

Download or read book Practical Environmental Bioremediation written by R. Barry King and published by CRC Press. This book was released on 1997-12-29 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bioremediation, or enhanced microbiological treatment, of environments contaminated with a variety of organic and inorganic compounds is one of the most effective innovative technologies to come around this century! Practical Environmental Bioremediation: The Field Guide presents updated material, case histories and many instructive illustrations to reflect the evolving image of this fast-emerging industry. Bioremediation technology has witnessed great strides towards simplifying treatability formats, finding new approaches to field application, more potent nutrient formulations, monitoring protocols and the resulting general improvement in results. This new guide condenses all current available knowledge and presents necessary technical aspects and concepts in language that can be readily comprehended by the technical student, experienced scientist or engineer, the aspiring newcomer, or anyone else interested in this exciting natural cleanup technique.

Download or read book Exploring Biodegradation of Emerging Pollutants Using Next Generation Sequencing and Uplc MS MS Techniques written by Ke Yu and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Exploring Biodegradation of Emerging Pollutants Using Next Generation Sequencing and UPLC-MS-MS Techniques" by Ke, Yu, 余珂, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: This study was conducted to set up a systematic approach utilizing advantages of both wet lab and bioinformatic methodologies to study biodegradation abilities and microbial bacterial-functional relationship within bioremediation communities. Firstly, 11pharmaceuticals and personal care products (PPCPs)were selected as target chemicals for establishing an effective determination process in analyzing trace-level concentrations in the environment, and understanding the removal routes during pollutants removal process in wastewater treatment process using activated sludge. Ultra performance liquid chromatography-tandem mass spectrometry was utilized to develop a rapid, sensitive and reliable method without solid phase extraction pre-concentration for trace analysis of 11 PPCPs in influent and effluent from municipal wastewater treatment plants. Shorten the detection time and significant reduction of detection cost were achieved due to the omitting usage of solid phase extraction (SPE)process and avoiding the consumption of hydrophiliclipophilic balancced (HLB)cartridge. Research on removal routes of ten selected PPCPs in activated sludge found activated sludge hardly removed carbamazepine. Biodegradation was the sole route to remove acyclovir, metronidazole, benzylparaben, ethylparaben, methylparaben and propylparaben. Both adsorption and biodegradation were involved in the removal of ranitidine and benzophenone-3, while fluoxetine could be totally removed by adsorption in activated sludge. Secondly, as the target microbial community, activated sludge community was used to set up the global bioinformatic analysis process. Both metagenomic and metatranscriptomic approaches were processed to characterize microbial structure and gene expression of activated sludge community. The taxonomic profile showed thatactivated sludge was dominated by Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Verrucomicrobiaphyla. Gene expression annotation of nitrogen removal revealed that denitrification-related genes sequences dominated in both DNA and cDNA datasets while nitrifying genes were also expressed in relative high levels. Specially, ammonia monooxygenase and hydroxylamine oxidase demonstrated the high cDNA/DNA ratios, indicating strong nitrification activity. Ammonia-oxidizing bacteria present mainly belonged to Nitrosomonas and Nitrosospira species. A fast method to construct local sub-databases has been established for the quick similarity search and annotation of huge metagenomic datasets. The conducted tests showed sub-database annotation pipeline achieved a speedup of 150-385 times, and got exactly the same annotation results with those of the direct NCBI-nr database BLAST-MEGAN method. This approach provides a new time-efficient and convenient annotation similarity search strategy for laboratories without access to high performance computing facilities. Thirdly, bisphenol A(BPA), which has a partially known biodegradation pathway and relevant bioremediating genes, was chosen as a model to establish a pipeline for systematical understanding the pathways and gene/bacteria relationships in an enriched microbial community. 11 new metabolites were detected during BPA degradation. Thereby, a novel pathway of degrading BPA metabolite was proposed. Sphingomonas strains were dominant taxa in initial degradation of BPA, while the other

Download or read book Biodegradability of Organic Substances in Aquatic Envir written by Pavel Pitter and published by Springer. This book was released on 1990-07-05 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Anaerobic Biodegradation of Selected Organic Compounds with and Without Inhibition of Sulfate Reducing Bacteria written by Tinker R. McBrayer and published by . This book was released on 1989 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biodegradation of Selected Volatile Organic Compounds in the Anaerobic Digestion of Primary and Secondary Sewage Sludges written by Thomas L. Crawford and published by . This book was released on 1990 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: