THICK SOLIDS DIGESTION – RESEARCH, DESIGN AND VALIDATION OF KEY PROCESS UNIT OPERATIONS
Authors: Cumiskey, Aidan; Dawson, Mick; Tillotson, Martin
Source: Proceedings of the Water Environment Federation, WEF/AWWA/CWEA Joint Residuals and Biosolids Management 2003 , pp. 1415-1432(18)
Publisher: Water Environment Federation
Abstract:Advances in the design of anaerobic digesters have seen a trend towards digestion of thicker sludges in the US, UK and elsewhere. This includes a number of new facilities using bolt on technologies to mesophilic anaerobic digestion such as Cambi Thermal Hydrolysis, Prepasteurisation and Biological Hydrolysis. Cambi Thermal hydrolysis utilises thickened sludge and the digestion process is fed at high DS%, typically 12-14%w/wDS thereby intensifying the digestion process and reducing reactor volumes.
There is limited experience in the design of digestion systems for such applications including heating, mixing and pumping. As the trend continues towards advanced digestion technology, a greater emphasis will be placed on these basic unit process operations. Monsal have conducted fundamental research into digester heating and mixing technology in collaboration with British Hydraulics Research group (BHR) and Yorkshire Water. A number of plants have been designed using design tools generated from the research. This includes the digester mixing systems for a major sludge processing facility in Scotland, which is an advanced digestion facility employing Cambi Thermal Hydrolysis followed by mesophilic anaerobic digestion. This advanced facility treats a design PE of 562,000, processing 16,000 tds/year of hydrolysed sludge utilising two 4000 m3 digesters.
This paper looks at the design of the mixing technology for thick feed sludges for the full scale plant. The background research is examined and reviewed. The conceptual design is examined and reported. The full scale design and testing is also reported and examined being compared with the design stage. The paper looks at the use of fundamental sludge rheology to design effective systems for thick sludge digestion and reports on the effects of thermal hydrolysis pretreatment.
Document Type: Research Article
Publication date: January 1, 2003
- Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed. WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access.
- Subscribe to this Title
- Membership Information
- About WEF Proceedings
- WEFTEC Conference Information
- ingentaconnect is not responsible for the content or availability of external websites