In a world where there is a growing awareness of the possible effects of human activities on climate change, there is a need to identify the emission of greenhouse gases (GHG) from wastewater treatment plants (WWTPs). As a result of this growing awareness, governments started to implement regulations that require water authorities to report their GHG emissions. With these developments there exists a strong need for adequate insight into the emissions of N2O and CH4. With this insight water authorities would be able to estimate and finally reduce their emissions. The overall objectives of the different research programs performed by partners of the GWRC members WERF (United States of America), WSAA (Australia), CIRSEE-Suez (France) and STOWA (the Netherlands) were: To define the origin of N2O emission. To understand the formation processes of N2O. To identify the level of CH4 emissions from wastewater collection and treatment systems. To evaluate the use of generic emission factors to estimate the emission of N2O from individual plants

Because of the uneven distribution of fresh water in time and space and the increasing human population, a large number of regions are experiencing water scarcity and stress. Membrane-based desalination technologies like reverse osmosis have the potential to solve the fresh water crisis in coastal areas. However, in many cases membrane performance is restricted by biofouling. Biofouling of Membrane Systems gives a comprehensive overview on the state of the art strategies to control biofouling in spiral wound reverse osmosis membrane systems and point to possible future research directions. Despite the fact that much research and development has been done to overcome biofouling in spiral wound membrane systems used for water treatment, biofouling is still a major practical problem causing performance decline and increased energy demand. Biofouling of Membrane Systems is divided into three sections including modelling and numerical analysis, non-destructive characterization and feed spacer geometry optimization. It focuses on the development of biomass in the feed channel of the membrane module and its effect on pressure drop and hydrodynamics. This book can be used to develop an integral strategy to control biofouling in spiral wound membrane systems. An overview of several potential complementary approaches to solve biofouling is given and an integrated approach for biofouling control and feed spacer design is proposed.

Wastewater and drinking water treatment are essential elements of urban infrastructure. In the course of the last century there has been enormous technical development, so successful that for the general public in industrialized countries this infrastructure is hardly noticed. Nevertheless there is ongoing activity to further improve the existing processes. The IWA Leading Edge Technology conference held in Prague helped to stimulate this development and this book helps disseminate the results. A selection of presentations from the conference are included in this volume. Wastewater and drinking-water treatment are normally considered as two separate fields due to the very different boundary conditions that apply. Nevertheless several issues such as membrane processes, removal of micropollutants and water reuse are of crucial importance to both. This potential for cross-fertilization further enhances the value of this collection of high-quality articles that delineate the leading edge of research and development in water and wastewater treatment.