Total Energy Consumption For Municipal Wastewater Treatment

Quantities of all forms of energy consumed for collection and treatment of municipal wastewater are estimated. Heat energy is equated to electrical energy by a conversion factor of 10,500 Btu/kwh. Total energy consumption, expressed as kwh/mg of wastewater treated, ranges from 2300-3700 kwh/mg. Energy used for construction of the treatment plant and the sewerage system represents 35-55% of the total energy consumed. The remainder used for plant operation is predominately (65-75%) electrical energy. The use of high efficiency aeration devices combined with good maintenance practices appears to offer the best opportunity for conservation of energy within the plant. Recovery of energy from the sludge produced at the plant can be accomplished by anaerobically digesting the sludge and using the digester gas as fuel for internal combustion engines. In large plants, when the sludge is sufficiently dewatered, it is also possible to recover energy by incinerating the dewatered sludge with production of steam in a waste heat boiler. The steam can then be used within the plant or expanded through a steam turbine to produce mechanical or electrical energy.

The principle of the conventional activated sludge (CAS) for municipal wastewater treatment is primarily based on biological oxidation by which organic matters are converted to biomass and carbon dioxide. After more than 100 years’ successful application, the CAS process is receiving increasing critiques on its high energy consumption and excessive sludge generation. Currently, almost all municipal wastewater treatment plants with the CAS as a core process are being operated in an energy-negative fashion. To tackle such challenging situations, there is a need to re-examine the present wastewater treatment philosophy by developing and adopting novel process configurations and emerging technologies. The solutions going forward should rely on the ways to improve direct energy recovery from wastewater, while minimizing in-plant energy consumption. This book begins with a critical overview of the energy situation and challenges in current municipal wastewater treatment plants, showing the necessity of the paradigm shift from removal to recovery in terms of energy and resource. As such, the concept of A-B process is discussed in detail in the book. It appears that various A-B process configurations are able to provide possible engineering solutions in which A-stage is primarily designed for COD capture with the aim for direct anaerobic treatment without producing excessive biosludge, while B-stage is designated for nitrogen removal. Making the wastewater treatment energy self-sustainable is obviously of global significance and eventually may become a game changer for the global market of the municipal wastewater reclamation technology. The principal audiences include practitioners, professionals, university researchers, undergraduate and postgraduate students who are interested and specialized in municipal wastewater treatment and process design, environmental engineering, and environmental biotechnology.

Special Offer: Cao Ye Shi Author Set - Buy all three books together and save a total £76! Mass Flow and Energy Efficiency of Municipal Wastewater Treatment Plants presents the results of a series of studies that examined the mass flow and balance, and energy efficiency, of municipal wastewater treatment plants; it offers a vision of the future for municipal wastewater treatment plants. These studies were undertaken as part of the R & D program of the Public Utilities Board (PUB), Singapore. The book covers the latest practical and academic developments and provides: a detailed picture of the mass flow and transfer of Chemical Oxygen Demand (COD), solids, nitrogen and phosphorus and energy efficiency in a large municipal wastewater treatment plants in Singapore. The results are compared with the Strass wastewater treatment plant, Austria, which reaches energy self-sufficiency, and the approaches for improvement are proposed. a description of the biological conversions and mass flow and energy recovery in an up-flow anaerobic sludge blanket reactor - activated sludge process (UASB-ASP) - and compares this to the conventional activated sludge process. a comprehensive and critical review of the current state of the art of energy efficiency of municipal wastewater treatment plants including benchmarks, best available technologies and practices in energy saving and recovery, institution policies, and road maps to high energy recovery and high efficiency plants. a vision of future wastewater treatment plants including the major challenges of the paradigm shift from waste removal to resource recovery, technologies and processes to be studied, integrated sanitation system and management and policies. Mass Flow and Energy Efficiency of Municipal Wastewater Treatment Plants is a valuable reference on energy and sustainable management of municipal wastewater treatment plants, and will be especially useful for process and design researchers in wastewater research institutions, engineers, consultants and managers in water companies and water utilities, as well as students and academic staff in civil/sanitation/environment departments in universities.

Rapid and important developments in the area of energy - water nexus over the last two to three years have been significant. This new edition of Water and Energy: Threats and Opportunities is timely and continues to highlight the inextricable link between water and energy, providing an up-to-date overview of the subject with helpful detailed summaries of the technical literature. Water and Energy has been up-dated throughout and major changes are: new chapters on global warming and fossil fuels, including shale gas and fracking; the consequences of the Deepwater Horizon accident in the Mexican Gulf and the Niger Delta oil spills; new developments in hydropower; and continued competition between food, water and energy. Water and Energy Threats and Opportunities, 2e creates an awareness of the important couplings between water and energy. It shows how energy is used in all the various water cycle operations and demonstrates how water is used and misused in all kinds of energy production and generation.Population increase, climate change and an increasing competition between food and fuel production create enormous pressures on both water and energy availability. Since there is no replacement for water, water security looks more crucial than energy security. This is true not only in developing countries but also in the most advanced countries. For example, the western parts of the USA suffer from water scarcity that provides a real security threat. Part One of the book describes the water-energy nexus, the conflicts and competitions and the couplings between water security, energy security, and food security. Part Two captures how climate change, population increase and the growing food demand will have major impact on water availability in many countries in the world. Part Three describes water for energy and how energy production and conversion depend on water availability. As a consequence, all planning has to take both water and energy into consideration. The environmental (including water) consequences of oil and coal exploration and refining are huge, in North America as well as in the rest of the world. Furthermore, oil leak accidents have hit America, Africa, Europe as well as Asia. The consequences of hydropower are discussed and the competition between hydropower generation, flood control and water storage is illustrated. The importance of water for cooling thermal power plants is described, as this was so tragically demonstrated at the Fukushima nuclear plants in 2011. Climate change will further emphasize the strong coupling between water availability and the operation of power plants. Part Four analyses energy for water - how water production and treatment depend on energy. The book shows that a lot can be done to improve equipment, develop processes and apply advanced monitoring and control to save energy for water operations. Significant amounts of energy can be saved by better pumping, the reduction of leakages, controlled aeration in biological wastewater treatment, more efficient biogas production, and by improved desalination processes. There are 3 PowerPoint presentations available for Water and Energy - threats and opportunities, 2e. About the author Gustaf Olsson, Professor Em. in Industrial Automation, Lund University, Sweden Since 2006, Gustaf has been Professor Emeritus at Lund University, Sweden. Gustaf has devoted his research to control and automation in water systems, electrical power systems and process industries. From 2006 to 2008 he was part time professor in electrical power systems at Chalmers University of Technology, Sweden. He is guest professor at the Technical University of Malaysia (UTM) and at the Tsinghua University in Beijing, China and he is an honorary faculty member of the Exeter University in UK. Between 2005 and 2010 he was the editor-in-chief of the journals Water Science and Technology and Water Science and Technology/Water Supply, (IWA Publishing). From 2007 to 2010, he was a member of the IWA Board of Directors and in 2010 he received the IWA Publication Award. In 2012 he was the awardee of an Honorary Doctor degree at UTM and an Honorary Membership of IWA. Gustaf has guided 23 PhDs and a few hundred MSc students through their exams and has received the Lund University pedagogical award for distinguished achievements in the education". The Lund University engineering students elected him as the teacher of the year He has spent extended periods as a guest professor and visiting researcher at universities and companies in the USA, Australia and Japan and has been invited as a guest lecturer in 19 countries outside Sweden. He has authored nine books published in English, Russian, German and Chinese and and contributed with chapters in another 19 books as well as more than 170 scientific publications.

Written and edited by a team of industry experts, this exciting new volume covers clean energy production from sewage and biomass while achieving a zero-waste strategy. Wastewater treatment plants are critical in protecting both the environment’s resources and human health. A wastewater treatment plant’s technological system focuses not only on the effectiveness of the treatment but on the costs and energy consumption of the entire system. Municipal wastewater treatment produces a significant amount of sewage sludge all over the world. The majority of this sludge’s dry matter content is made up of organic compounds which are not toxic, and they consist of both primary and secondary (microbiological) sludge. There is also a substantial quantity of inorganic substances in the sludge, along with a small quantity of toxic matter. Also, various raw sewage treatment options can include energy production (heat, electricity, or biofuel) to reduce dependence on external energy supply during treatment. The most important options used for energy production from sewage and biomass can use the following approaches: anaerobic digestion, co-digestion, incineration with energy recovery, co-incineration, pyrolysis, gasification, supercritical (wet) oxidation, and hydrolysis. Generally, these processes or methods are cost-effective, but they can still have some setbacks related to the nature of the methods or the raw material used for conversion. There are also operating conditions to comply with to get a successful outcome. This book combines information from many disciplines related to wastewater treatment technologies to show how the circular economy approach can be used to achieve zero waste and produce energy that can be useful for plants and communities. This approach focuses on clean technologies for green energy resources such as biohydrogen, biofuels, and biogas from biomass and sewage sludge for zero waste production. This is aimed to also integrate the issue of energy demand and the one of energy production.