Biomethane Plant Optimisation
case study
about the project
The bio-methane plant based at SITA’s landfill site in Surrey was commissioned in June 2008 with the capability of producing approximately 4,300 tonnes of liquid bio-methane per annum (equivalent to 5.2m litres of diesel).
The plant was designed as a number of discrete packages without an overall process or control philosophy. During the early stages of operation, the facility produced on average 6 tonne/day compared with the expected 16 tonne/day. We were engaged to provide an engineering study to assess optimising performance and present this to the client with recommendations for a Return on Investment (RoI) proposal.
Through executing a number of site surveys and working with the clients process engineers, we established a number of potential causes and key areas for improvement:
• The field Instrumentation was poorly commissioned, inadequate and unreliable causing process upsets. This had a direct correlation with lost production time
• The plant processes adopted a significant amount of manual operations for a complex environment. These processes had the potential for increased operator induced error leading to undesired process upsets. These errors had a direct correlation with lost production time.
We supplied a final engineering study to the client, supported by a RoI plan for each initiative. By using the output from our engineering studies the client was able to immediately implement the zero and low CAPEX recommendations.
We identified a maximum increase in revenue of £3.6m/year. Furthermore, we identified that automating the manual processes and optimising the control system would result in an increased revenue of approximately £800k per annum.
By providing a RoI analysis, we were able to demonstrate to the client that the optimisation initiatives could be funded in stages. This had the obvious benefit of enabling the client to reinvest the profit for each initiative, without any significant CAPEX outlay.