An online non-contact wastewater pollution Load Monitor (LOADMON)

PI: Dominic O’Brien, Steve Sheard (Oxford University), Steve Russel (WRc), PostDoc: Xuewu Dai, TSB, 2011-2013

Increasing energy prices and labour costs have industries to seek a innotative way to improve energy efficiency and plant control performance. The advanced control systems for the activated sludge process in water companies need real-time measurements of the organic load of crude and settled sewage so that the compliant chemical oxygen demand (COD) and suspended solids (SS) level of discharged wastewater is maintained, but less power is consumed to pump the air.

A fully non-contact optic sensor and an integrated instrument for wastewater treatment work are being developed under the collabration between University of Oxford and WRc plc. The sensor uses light at different wavelengths to interrogate a flowing sample in an open channel. From the scattered light received, the SS and COD can be deduced and from this, the particulate and dissolved organic load. The istrument is immune to fouling. LOADMON project will develop the method in the laboratory, then build and site test a pre-production prototype with a manufacturing partner. This development is supported by TSB, United Utilities, Severn Trent Water, Northumbrian Water and Northern Ireland Water. Further similar products could be developed in the future for sewer network and combined sewer overlow (CSO) use.