Case studies – Page 5 – Carbon Neutral Urban Water

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

GUIA’s WWTP 0-100% Energy self-sufficient

Guia’s Wastewater Treatment Plant (WWTP) one of EPAL main assets, is the largest Portuguese WWTP and one of the main engineering works in Portugal due to the complexity of its technical solution, the requirements of the receiving environment (bathing area) and urban planning (tourist zone).

The Biosolids Emissions Assessment Model (BEAM)

Biosolids management practices are evaluated based on environmental, economic and social impacts. A consideration of increasing importance is the impact of greenhouse gas (GHG) emissions from biosolids (treated sludge). BEAM tool was developed for calculating GHG emissions from biosolids management.

Guidelines on Energy Efficiency on Water and Wastewater Utilities

These EE-Guidelines were tested by three pilot utilities, SONEDE in Tunisia, ONEE in Morocco and Aqaba Water Company in Jordan. The energy checks and energy analysis at the water supply facilities were guided and supported by German experts from Hamburg Wasser, a company with longstanding experience in energy management – and known for its strategic target to be independent from external energy inputs before the year 2020.

Separating sewage from rainwater in Vancouver

Vancouver is working toward the Province of BC’s environmental goal to eliminate sewage overflows by 2050. As the City replaces combined sewer systems with separated sewer systems, properties will also need to have separated sewer systems.There are two sewer separation programs running concurrently in the City. The overall sewer mains are being separated so that storm drains carry stormwater runoff separately from other wastewater.

Water loss management: A case study in Korea. Water Practice & Technology

A case of water loss management on a small city whose water supply is approximately 34,000 ?/day is examined. Revenue water ratio was just 55% mostly because of water loss caused by old pipes and difficulties in pipeline management in the beginning 2004. From 2005 to 2006, 50 km of pipe was replaced due to leaks, poor resultant water quality, blockage or corrosion. In all the new pipes, water meters and valves were replaced as well. This has already led to water savings, and the city plans to continue maintaining and replacing pipes as needed. Overall, through systematic management and rehabilitation/replacement of pipelines, water leakage has decreased dramatically, and the revenue water ratio has increased from 55% to 70% in just 2 years.

Benefits and drawbacks of thermal pre-hydrolysis for operational performance of wastewater treatment plants

This paper presents benefits and potential drawbacks of thermal pre-hydrolysis of sewage sludge from an operator’s prospective. The innovative continuous Thermo-Pressure-Hydrolysis Process (TDH) has been tested in fullscale at Zirl wastewater treatment plant (WWTP), Austria, and its influence on sludge digestion and dewatering has been evaluated. A mathematical plant-wide model with application of the IWA Activated Sludge Model No.1 (ASM1) and the Anaerobic Digestion Model No.1 (ADM1) has been used for a systematic comparison of both scenarios – operational plant performance with and without thermal pre-hydrolysis. The impacts of TDH pre-hydrolysis on biogas potential, dewatering and return load in terms of ammonia and inert organic compounds (Si) have been simulated by the calibrated model and are displayed by Sankey mass flow figures. Implementation of full scale TDH process provided higher anaerobic degradation efficiency with subsequent increased biogas production (+75-80%) of waste activated sludge (WAS). Both effects – enhanced degradation of organic matter and improved cake’s solids content from 25.2 to 32.7% TSS – promise a reduction in sludge disposal costs of about 25%. However, increased ammonia release and generation of soluble inert Si was observed when TDH pre-hydrolysis was introduced to WWTP.

Energy self-sufficiency as a feasible concept for wastewater treatment systems

Energy Recovery from Wastewater Treatment Plants in the United States: A Case Study of the Energy-Water Nexus

Energy recovery from wastewater treatment plants via anaerobic digestion with biogas utilization and biosolids incineration with electricity generation. We estimate that anaerobic digestion could save 628 to 4,940 million kWh annually in the United States. In Texas, anaerobic digestion could save 40.2 to 460 million kWh annually and biosolids incineration could save 51.9 to 1,030 million kWh annually.

United Utilities, Davyhulme WWTW, CHP Plant

At the Davyhulme wastewater treatment works (WWTW) in Greater Manchester, United Utilities is generating renewable energy from sewage gas that is created from sludge left behind after the treatment of wastewater. United Utilities spent £100 million on the programme that leaves the sludge behind to be used to power the site. At the site 90,000 tonnes of sludge is being processed a year. Clarke Energy has supplied 2 new GE’s Jenbacher JMS620 GS-BL gas engines and re-located 3 x JMS620 GS-BL existing engines to Davyhulme for this project, together creating 12.0MW of renewable power. This is the equivalent of powering over 10,000 typical UK homes.

Resource Type: Case studies