With over 150 wastewater treatment installations operating worldwide, Wehrle’s typical technical solution would include a de-packaging & separation step, a pasteurization step followed by a two-step anaerobic digestion (AD) system that produces a valuable biogas resource – an energy gain from the system. Using a combined heat and power (CHP) plant, heat energy is generated from the biogas and recovered for use in pasteurization and in downstream processes, allowing full use of the UK government’s Renewable Heat Incentive in addition to payments from the Feed-In Tariff from renewable electricity production.
Digestate from the AD system would then typically be decantered and filtered through an ultrafiltration (UF) system before entering a series of processes to reduce phosphorous, ammonia and chemical oxygen demand (COD) levels. These would include a Bioscrub system for ammonia stripping, utilising more of the heat from the CHP system, and a membrane bioreactor (MBR) system producing treated water with low COD and ammonia resulting in lower Mogden charges. Alternatively, following additional post-treatment processes, the treated water can be reused on site to provide various beneficial uses and reduce waste disposal costs further.
As added benefits, the phosphorous removal and ammonia stripping processes each produce valuable inorganic fertilizers. In addition organic fertilizers are produced from the Anaerobic Digester and decanting processes and these provide local formers with useful products created out of what used to be seen as a waste disposal problem, which is now very much an economic and environmental opportunity for organic waste producers.
With an engineering and service office based in Witney, UK, Wehrle’s innovative treatment solutions are backed by an established and renowned German reputation for delivering reliable, proven and cost-effective solutions to a range of wastewater treatment problems including applications such as landfill leachate where ammonia and COD are also reliably reduced using MBR technology.
Systems are designed, installed, maintained and continuously optimised by Wehrle’s specialist engineers, who can operate plants to client requirements providing solutions from partial to full operation. Wehrle’s approach to wastewater treatment is unique. They focus on understanding site requirements and how to re-use existing equipment, through undertaking detailed feasibility studies and pilot trials, with the focus on maximising energy and economic profit from waste streams by using the full range of renewable energy incentives available.
Various technologies can be tested on site in process configurations to replicate the operation of full scale systems. Wehrle strive to re-use, refurbish and upgrade existing equipment where possible. The result is an efficient process solution at an affordable whole life cost with minimal installation and commissioning time. Systems have been engineered for various clients including Dairy Crest, Chivas Brothers, Dairy Gold, KP Foods, Cadbury’s and Kellogg’s.
Process solutions can be provided integrated into multiple containers or designed to fit into available space. This process engineering flexibility brings the benefits of both pre-installed components and bespoke design. By understanding requirements over the longer term, additional capacity can be planned in to allow future expansion at minimal cost. For further details please visit www.wehrle-env.co.uk.
Notes for Editors
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