Book excerpt: This concise introduction to the fundamentals of biological treatment of wastewater describes how to model and integrate biological steps into industrial processes. The book first covers the chemical, physical and biological basics, including wastewater characteristics, microbial metabolism, determining stoichiometric equations for catabolism and anabolism, measurements of mass transfer and respiration rates and the aerobic treatment of wastewater loaded with dissolved organics. It the moves on to deal with such applications and technologies as nitrogen and phosphorus removal, membrane technology, the assessment and selection of aeration systems, simple models for biofilm reactors and the modeling of activated sludge processes. A final section looks at the processing of water and the treatment of wastewater integrated into the production process. Essential reading for chemists, engineers, microbiologists, environmental officers, agencies and consultants, in both academia and industry.