Progress in Environmental Engineering contains theoretical and experimental contributions on water purification, new concepts andmethods of wastewater treatment, and ecological problems in freshwater ecosystems. The issues dealt with in the book include:(i) Causes and control of activated sludge bulking and foaming(ii) e use of new support materials in activated sludge technology as a result of studies on wastewater treatment in a sequencing batch reactor with keramsite grains as the porous carrier in Moving Bed Sequencing Batch Biofi lm Reactors (iii) Greenhouse gas emissions from WWTPs espec