Anaerobic Digestion

Cepha Controls has extensive experience in the development and commissioning of controls systems for sewage and MSW digestion processes. We have developed control systems for the mesophilic and thermophic treatment processes for the sludge treatment centres, including the following systems:


Designed, developed and commissioned the sludge digestion process at Pyewipe Sludge Treatment Centre. The biogas produced was used in the Swiss Combi Sludge dryer and biogas boilers. Some years later, two CHP engines and a pre digester ultrasonic sludge treatment process was added to increase the gas production. The control system is based on the Rockwell range of PLC controllers and Wonderware Intouch SCADA package.


Designed, developed and commissioned a new Cambi Thermal Hydrolysis Process sludge treatment line at Ringsend WWTW, Dublin including a new digester. The biogas is used to run the three Swiss Combi thermal sludge dryers and runs four 1MW Jenbacher Gas Engines. The control system is based on the Rockwell rangeof PLC and Intouch SCADA. The control system for the two existing Thermal Sludge Dryers was upgraded from a legacy Mitsubishi systems to Rockwell including new safety and ATEX compliant systems.


Control system for the Digestion plant at Lowestoft WWTW including a Sludge Pasturisation process. The two digesters were designed to either operate as mesophilic or thermophilic digesters. The produced biogas was used to power two Caterpillar CHP gas engines. Lowestoft WWTW also had an Industrial Effluent treatment process including the Paques High Rate Internal Circulation (IC) bioreactors for treatment of effluent from a number of vegetable processing plants.


Modifications to the Waterbeach Food Waste digestion system, which is a small experimental AD plant operated by the Andigestion part of the Summerleaze group. We have modified and enhanced a control system for the Anerobic digestion facilty. The plant is a demonstration scale research and development plant. The research programme is evaluating the commercial and technical feasibility of treating various commercial materials including agricultural, biodegradable industrial, kitchen and animal by-product wastes.

The plant, which allows experimentation with a range of operational settings and novel technologies, is treating up to 10 tonnes of material per day.


Cranfield University – currently developing a control system for a new 1,500L Anaerobic Digestion Pilot Plant facility. The plant has investment from the European Regional Development Fund and will provide Cranfield University with a facility for AD research and to provide AD Renewable energy courses.


Brighton and Hove Waste Water and Sludge treatment facility  for Southern Water. The 7% dry solid sludge feeds three anaerobic mesophilic digesters with a 14-day retention time. Biogas produced in the digestion and post digestion tanks is used to generate energy  through the combined heat and power unit, and can be used to  heat the digesters and provide electricity for use on site. The sludge is then dewatered in Andritz centrifuges to 26% dry solids and then dried in an Andritz thermal drier, where it is formed into pellets which are exported off site for spreading to land.


Waste Recycling AD Plants in Manchester – involvement with the development and commissioning of the control system for the waste recycling and AD processes at both the Bredbury and Reliance Street facilities in Manchester.