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Pollution and its effects on the environment have emerged as critical areas of research within the past 30 years. The Handbook of Environmental Engineering is a collection of methodologies that study the effects of pollution and waste in their three basic forms: gas, solid, and liquid. In Volume 8, Biological Treatment Processes, tried-and-true solutions comprise a 'methodology of pollution control'. The distinguished panel of authors contributes detailed chapters, which include topics ranging from treatment by land application, activated sludge processes, and submerged aeration to trickling filters, lagoons, rotating biological contactors, sequencing batch reactors, digestions, and composting. Volume 8 and its sister book - Volume 9: Advanced Biological Treatment Processes - are designed as both basic biological waste treatment textbooks and reference books for advanced undergraduate and graduate students - as well as for designers of waste treatment systems, scientists, and researchers. An indispensable addition to the Humana Press series, Volume 8: Biological Treatment Processes provides an illuminating look at water pollution control and the fascinating evolution of bio-environmental engineering.

[eng] Comprising over 70% of the Earth's surface, water is undoubtedly the most precious natural resource that exists on our planet. Without the seemingly invaluable compound comprised of hydrogen and oxygen, life on Earth would be non-existent: it is essential for everything on our planet to grow and prosper. Although we as humans recognize this fact, we disregard it by polluting our rivers, lakes, and oceans. Subsequently, we are slowly but surely harming our planet to the point where organisms are dying at a very alarming rate. In addition to innocent organisms dying off, our drinking water has become greatly affected as is our ability to use water for recreational purposes. In order to combat water pollution, we must understand the problems and become part of the solution. When is compared with other options of processing, biological treatment of residual water is considered a cheap and attractive alternative to eliminate various types of contaminants. The effíciency of the biological process depends on many factors such as the concentration of the contaminants, the chemical structure of the composed, the pH and the presence of inhibitory compounds in wastewater. Although some organic contaminants can be degraded through biological process, many other composed synthetic and natural are not biodegradable. On the hand, several chemical processes as advanced oxidation processes (AOP's) can be use for mineralization of many organic contaminants. The doubt that presents these processes is the use of expensive reagents. A potential viable solution proposed during last two decays is the combination of these processes with biological processing. In these combined processes, the chemical process would be utilized like pre-treatment step to enhance the biodegradability and elimínate the toxicity of the effluents, while the total mineralization would be completed in the biological process. For it, it is interesting to monitor the changes in the biodegradability of the effluents along the chemical process, this may be use to determine the optimum pre-treatment time. In the literature various indicators have been proposed to follow the biodegradability, where the ratios BOD5/COD and BOD5/TOC are the most utilized (BOD: Biological oxygen demand); COD: Chemical oxygen demand; TOC: total organic carbón). In general, are municipal wastewater was taken as reference values. Thus, it is considered that an effluent is biodegradable when the relation BOD5/COD is over 0.4 or BOD5/TOC over 1.0 (Metcalf & Eddy, 1985). The AOP's are defined like those processes that imply the generation of radicals highly reagents (especially radical hidroxilo) in suffícient quantities. Although most organic matter can be degraded by these processes, other compounds as the acetic acids,maleico and oxálico, acetona or cloroformo are not attacked by these radicals (Bigda,1995). The advantage of AOP's comes from the fact that radicals can be formed through different processes. In this study, AOP's based on photo-oxidation well be used for treatment of water contained Phenol and 2,4-dichlorophenol. In the first chapter of this work a general literature review the reactions are presented in which a series of methods for the treating refractory were proposed, among them is found the adsorption in active carbon, humid oxidation, supercritical oxidation, electrochemical oxidation, chemical oxidation in its two parts classics and advanced oxidation. For all, a small bibliographical search as well previous publication in elimination of phenol (POH) and 2,4-dichlorophenol (DCP) are presented. Moreover, it was presented a basic explanation of the characteristics of the biological processing and its operational types. At the end of this chapter, it has been introduced a figure (Figure 3.4) that shows a possible strategy to treat any type of wastewater depending on the organic load and the biodegradability. With respect to the results, the thesis present a framework of the combination of AOP's and biological treatment. In this case, synthetic residual water containing phenol (POH) and 2,4-diclorophenol (DCP) and textile dyes.These compound associates as contaminants in different types of water. They appear in different types of industrial effluents and included among the 130 priority contaminants gives by US EPA and the European Union. A study of the behaviour of these substances for a possible biological degradation showed that all presented low biodegradability, and some as the DCP and textile dyes were inhibited for biomass. Thus, it was necessary to seek alternatives treatment processes. In a first part of this work, the degradation of these composed was studied by means of advanced oxidation processes (AOP's), based on the use of the process of photo oxidation, in this case, direct irradiation with light UV or UVA, and combination these sources of light with; UV(A)/H202, UV(A)/Fe(III),UV(A)/Fe(II)/H202 and the process Fenton. These experiments were performed in four different, two of them are type tubular and the other two are type stirred tank. The followed variables along the process were the concentration of the contaminants, pH, initial concentration of the H202, Conc. Initial of Fe(II), time of irradiation and total organic carbon (TOC). The effect of irradiation time in the degradation of both the POH and DCP was studied. Also, kinetic of the reactions were followed. Results show that direct UV photolysis is not efficient for DCP and POH elimination. First order reaction constant of aprox. 0.0056 min-1 and 0.0066 min-1 was obtained for POH and DCP, respect.) Also the combinations of this process with other hydroxyl radical sours were studied, for e. j., the effect of the quantity of peroxide or Fa(II), or the black light irradiation with UV at (300-420 nm) vs. 254 nm. By means of the combination H202/UV/Fe removals percentages of 100 DCP and POH were achieved. During these reactions, by-products were identified, for POH it was identified caticlos, quinone and hidroquinoin. In the case of DCP, only it was possible to identify the clorobenzoquinona and some carboxylic acids. As it was mentiond above, the hostility that AOP's presents is use of expensive reagents, and a possible alternative is the combination with biological process. In this study also, some strategies for these types of combination have been established, that was possible by means of a study of the improvement in the biodegradability of the treated solutions. In a second part of the work, therefore, the effect of these processes was studied in the biodegradability enhancement of the solutions. The better results were obtained by means of the process photo-Fenton, the ratios BOD5/COD increased from O up to 0.92 and 0.48 for solutions of 100 ppm of POH and DCP respectively. After time of irradiation of 30 min and initial concentrations of H2 02 of 65 ppm and 300 ppm, respectively. Later the improvement of the biodegradability of the treated solutions, was studied the biodegradation of some solutions pre-tried of POH and DCP. Respect the DCP treated, the results have shown that activated sludge of a municipal wastewater plant could be adequate for the treatment of the pre-oxidize solutions and that was possible through co-digestion of the same with a residual water. By means of the combination photo Fenton -biological treatment. It was achieved up to a 89 of organic matter elimination. Continuing this line of investigation, it was developed also a complete combined processes consist of DCP pre-treated via Photo oxidation and aerobic and anaerobio biological reactors type SBR (sequencing batch reactor). By means of this process, elimination of organic matter up to 93 of TOC was obtained in a signifícant cycle time. The same strategy was applied to phenol, in this part a comparison has been established between single and coupled processes, the results have been shown that good improvement in organic matter take place in the combined processes. Finally, the use of the photo oxidation processes was examined to eliminate the colour and improvement the biodegradability of dyes solutions. The results have shown that these processes can be use efficiently for colour elimination and biodegradability improvement of dyes solutions.

1. Food industry as a source of waste and by-products -- 2. Anaerobic digestion of waste and by-product from food industry -- 3. Composting of waste and by-product from food industry -- 4. Environmental aspect of waste and by-product from food industry and their management.

In 2009 the Norwegian government banned biodegradable waste in landfills to mitigate climate gas production. To be able to stabilize source separated waste before landfilling a constructed biocell has been tested during a four year period. The research is part of a pilot project organized by Avfall Norge. A total amount of 12 000 tons of waste from both industry and households were embedded in the biocell. Before loading, the waste fractions were characterized both in macro and micro scale. Anaerobic testing in lab scale documented the methane potential in different waste fractions. Especially car fluff contained toxic components which suppressed biodegradation. To avoid greenhouse gas leakage the biocell was constructed as a closed system with synthetic capping and gas wells coupled to a compressor. While the biogas was flared the leachate was collected and recycled. Leachate contains both nutrients and DOC which is supposed to increase the biological activity. During the first part of the test period the BOD/COD was above 0.5 before it declined. In addition both inorganic and organic environmental harmful components were analyzed in the leachate. Levels of heavy metal decreased during treatment. The methane production was detected on-line with IR. Both the production and gas phase concentration varied during the test period. A total of five gas wells were positioned at different levels in the biocell. Only one of them produced biogas for a considerable period. This presentation will focus on biocell construction and waste degradation related to variation in leachate constituents as a function of time.