Plant manager, James Wood, wanted to monitor biogas composition automatically 24 hours a day, seven days a week. He wanted his own independent analysis of the gas mix and to record it in detail, especially the percentage of methane, hydrogen sulphide and carbon dioxide.
How the company uses the GA3000 PLUS product
James said: “We want our own gas analysis record of the biogas quality we are sending to the 496kW Jenbacher CHP engine or to flare. To control H2S we dose with ferric sulphide every day. The amount is determined by the H2S percentage reading from our Geotech GA3000 PLUS fixed analyser. It also shows if there is too much CO2 and we also rectify that.”
This careful management of the plant now contributes to avoiding unplanned CHP downtime at a direct revenue loss of £2000 a day (11.8MWh of electricity).
The GA3000 PLUS in use
The anaerobic digester plant started generating heat and power in 2011. Using a continuous feed of farm and food waste, it is anticipated to offset the university campus carbon emissions more than three times over and save over 13,000 tonnes of CO2. It provides electricity to the campus population of 2500 people and sells surplus electricity to the electricity grid.
Renewable electricity is produced from food and farm waste and provides a highly effective waste management system. The waste is digested in the anaerobic digester and recycled into 23,000 tonnes of liquid, nutrient-rich fertiliser for use on University College farm, reducing reliance on chemical-based fossil-fuel created fertilisers. The feedstock comes from 8,500 tonnes of municipal food waste from households, restaurants and food production which would otherwise go to landfill.