Project Appreciation and Objectives
Regeneration of granular activated carbon (GAC) is a significant operating cost at many water treatment works, which is increasing with the identification of new problem organic micropollutants, particularly pesticides. Usually, regeneration frequency is established to safely minimise risk of breakthrough of contaminants, with a high level of security and associated cost.
This project will develop techniques for estimating GAC bed life with greater confidence to allow regeneration frequency and operating cost to be reduced. Ozonation is often used for pesticide degradation ahead of GAC, and the benefits of this will be taken into account in optimisation of GAC regeneration frequency. The software will be pre-calibrated with existing data, but a key feature will be the facility to update with operational data for specific works.
Benefits to Clients
- Reduced operating cost for organic micropollutant removal without reducing the security of treatment.
- Risk assessment tool for Drinking Water Safety Plan (DWSP) development and implementation.
- Review test and measurement procedures to assess GAC loading and remaining bed life.
- Develop software to predict bed life for defined input conditions, including benefits from ozonation prior to GAC.
- Integrate the above two elements to provide a software tool for GAC management. This will allow estimation of bed life for regeneration regime planning and help evaluate alternative treatment management options for combined use of ozone and GAC - of benefit both in terms of operational management and DWSP implementation. The tool will also assist in process selection and design for ozone/GAC systems.
- Demonstrate the tool using data from participating companies for a range of organic micropollutants and operating conditions.
- Practical, software-based operational tool for cost-effective management of GACs.
- Dissemination workshop.
- Final report.
- Development of GAC and ozonation software tools for removal of algal toxins as part of the EU "TOXIC" project, 2002-2005.
- Investigation of pesticide removal using GAC for a wide range of single client projects, including simulation modelling using the WRc GACman software.
- Portfolio projects on removal of "emerging" organic micropollutants and pesticides, including metaldehyde, using GAC and ozonation CP317, 2006; CP354, 2008.
- Development of best practice guidance for GAC management, CP001, 2002.