This brochure gives an overview on joint research projects of the German Federal Ministry of Education and Research, which initiated the funding measure “Future-oriented Technologies
and Concepts for an Energy-efficient and Resource-saving Water Management” in 2012. Results show that the water-energy-nexus gives the crucial incentive for new energy and resource efficient solutions.
Resource Theme: Resource recovery
Resource recovery from wastewater in Austria: wastewater treatment plants as regional energy cells
This paper describes the estimation of total energy consumption and generation and the related degree of energetic self-sufficiency at certain Austrian WWTPs. Preliminary results regarding the development of a tool for evaluating and optimising on-site and externally supplied use of energy are presented. Finally, the possibilities of energy supply for neighbouring spatial structures are discussed briefly and conclusions drawn about the potential to develop WWTPs as regional energy cells.
Urban water networks as an alternative source for district heating and emergency heat-wave cooling
Three emergency cold recovery techniques are presented as a response to heat-waves: subway station cooling, ice production for individual cooling, and “heat-wave shelter” cooling in association with pavement-watering. The cold generation potential of each approach is assessed with a special consideration for mains water temperature sanitary limitations. Finally, technical obstacles and perspectives are discussed.
Recycling and Reuse of Treated Wastewater in Urban India
The document focuses on identifying the economic, financial and environmental benefits of wastewater recycling from the perspective of public spending. Also provides information on the evolution and current practices of wastewater recycling internationally and the international and national regulatory and policy frameworks that guide wastewater recycling. It presents possible strategies for city and state planners and policy makers to initiate the discourse on wastewater recycling and reuse.
Factsheet: Municipal Wastewater Methane: Reducing Emissions, Advancing Recovery and Use Opportunities
This factsheet provides a concise reference describing the sources of methane emissions in WW plants, and opportunities for methane recover and utlization. Additional two case studies are included describing recovery and use of methane within WWTPs globally.
The Roadmap to a Low-Carbon Urban Water Utility
An international guide to the WaCCliM approach
The Roadmap to a Low-Carbon Urban Water Utility presents utility managers with an approach to address their most pressing challenges, while reducing carbon emissions through
measures that either have a return on investment through energy or water savings, or that correspond to planned investments as part of the asset management plan to maintain or improve their services. Utilities adopting this approach are contributing to a carbon-neutral future, by instigating a change of mind-set, not only in urban water management but also by inspiring all other urban services through sharing the risks and the urgency to act to avoid aggravated impacts of climate change, of which water utilities are among the first victims: water scarcity, flooding and deteriorated water quality
Uso seguro del agua para el reúso
Gives a broad picture of wastewater treatment and reuse; its safe use as a fundamental aspect in water efficiency and security; technologies and biological processes for the treatment of wastewater destined for reuse, policies and regulations for the reuse of wastewater in some countries of Latin America (document is in Spanish).
Upgrading and methanisation projects at WWTP Avedøre
Enzymatic Biogas Upgrading
The techniques for removing CO2 from biogas are well known and available on the market in a number of ways to upgrade the biogas. Scrubbing with water or amine is most widely used methods. Common to all types is the large capital and operation cost (CAPEX & OPEX) in upgrading systems
A new technique is based on enzyme enhanced removal of the biogas’ content of CO2. The enzyme; Carbonic Anhydrase is well known as an accelerator for CO2 absorbtion and has been studied for decades. The enzyme is one of the fastest enzymes known in nature, and is present in all living organisms. Enzyme’s task is to transport CO2 in and out of the body tissue as lungs and muscles. The enzyme’s inability to remain active for longer periods in harsh industrial processes, has until now, prevented commercial use of the enzyme. Encapsulation of the enzyme in a gel has been tested in lab scale.
During spring 2015 Akermin and Ammongas will build a full-scale upgrading plant, that will handle the 3 million cubic meter biogas/year from WWTP Avedøre’s digesters.
The enzymes used in the project comes from Novozymes A/S,
In July 1, 2015 the biogas will be sent through the system and into the natural gas grid. The demonstration project will run until April 2017, and then will come a long period with commercial operation.
sludge2energy A way to energy self-sufficient sewage treatment plants
Co-incineration costs less, but on the other hand monoincineration provides the option of phosphorus recovery. Another factor in favour of incineration is the fact that it allows to recover the amount of energy consumed for sludge transport, dewatering and drying. It is an innovative concept of decentralised sludge utilisation by generation and use of thermal and electrical energy.The plant on WWTP Straubing is designed for 200,000 PE and presently treats about 35,000 m3 wastewater per day. After anaerobic sludge treatment and dewatering by means of centrifuges this is an annual volume of almost 9,000 t sludge dewatered to on average 28-29 % DR. The thermal energy content of dried sludge is a substantial value for the creation of an energy balance. The thermal value of dried sludge with 65% dry residue is comparable with brown coal and provides 1,020 kWh of energy. With according boiler efficiency, about 800 kWh of thermal energy can be generated. After deduction of further thermal losses in the micro gas turbine about 700 kWh of thermal energy effectively remain for the drying process. With a thermal energy consumption of about 565 kWh for the drying process there is even a surplus of energy available.
Use of biogas for cogeneration of heat and electricity for local application: performance evaluation of an engine power generator and a sludge thermal dryer
A small unit of cogeneration of energy and heat was tested at the Centre for Research and Training on Sanitation UFMG/COPASA – CePTS, located at the Arrudas Sewage Treatment Plant, in Belo Horizonte, Minas Gerais, Brazil. The unit consisted of an engine power generator adapted to run on biogas, a thermal dryer prototype and other peripherals (compressor, biogas storage tank, air blower, etc.). The heat from engine power generator exhaust gases was directed towards the thermal dryer prototype to dry the sludge and disinfect it. The results showed that the experimental apparatus is self-sufficient in electricity, even producing a surplus, available for other uses. The tests of drying and disinfection of sludge lasted 7 h, leading to an increase in solids content from 4 to 8% (50% reduction in sludge volume). Although the drying of sludge was not possible (only thickening was achieved), the disinfection process proved very effective, enabling the complete inactivation of helminth eggs.