Proceedings

The application of a Thermal Hydrolysis Process (THP) prior to sludge digestion is becoming more popular in the UK. Benefits are an increased production of methane and the production of class A biosolids post digestion. A potential disadvantage is the increase in release of ammonia in the digestion process, resulting in dewatering liquors with high ammonia concentrations. Application of a THP process can lead to a significant increase in nitrogen load on the main sewage treatment works.

The SHARON process for nitrogen removal over nitrite has been tested at laboratory scale for treatment of THP post digestion liquors. Liquors from various locations have been tested

This paper gives a brief introduction of the SHARON process and describes the results of the lab tests. Test results were used for the design of the SHARON process that is currently being built at Whitlingham STC (Anglian Water). The paper describes the design parameters applied for Whitlingham STC and the various considerations on process performance and process stability.