Microbial Fuel Cell Development and Optimisation

The objective of this project is to develop a market ready microbial fuel cell (MFC) which
will enable food & drink and other processing industries to produce biogas from the organic
fraction of its wastewater for effective fuel switching from fossil gas to renewable biogas. The
MFC therefore; produces hydrogen biogas to replace natural gas for single point emitters,
significantly reduces the chemical oxygen demand (COD) in waste water and produces
nitrogen rich microbial biomass as a substitute for mineral fertiliser. This project will build on
the successful outputs of a recent TSB funded feasibility study that transferred microbial fuel
cell (MFC) technology from the laboratory (18L bench scale) to an industrial demonstration
project (1,000L unit). The current 1000L MFC reduces 70% of organic compounds in solution
into hydrogen biogas and delivers a reduction of 66% in nitrates (converting slurry to grey
water) per day. The deliverable for this project will be a 25,000L unit - similar in size to a
standard 40 foot lorry container - that can operate on an industrial level. To put this into
context, it is anticipated that a dairy farm with 200 cows would require three of these units to
effectively process all of its waste. Lindhurst will utilise its engineering expertise and work
with the University of Nottingham (through the KTP scheme) with Arla Food UK plc as an
initial route to market. Arla has a 44% share of the fresh milk and cream market in the UK -
operating 8 dairies. One site, producing 7.5mL of milk per week operates a 2MW gas boiler.
The milk process water alone contains 4MW of energy. Thus there is a potential for Arla to
produce 2.8MW of biogas using MFCs from its effluent, enabling fuel switching an annual
carbon saving of 3,000t for this site alone. MFC is applicable across multiple industries and
therefore provides the UK with a huge potential for energy and carbon saving and for the
development of a novel technology with global potential.