The UK’s anaerobic digestion (AD) industry has grown rapidly to approximately 648 operational facilities. Identifying biogas leaks is one of the issues which AD operators have to face, but many are still failing to do so.
While most plant operators will monitor key parameters such as temperature, digester biology and biogas production on a regular basis, the vast majority do not check for gas leaks, believing it’s an issue which doesn’t affect their plant. However, over the last eight years, 85% of the 964 plants we have surveyed in the UK and Germany were suffering from biogas leakage. A quarter of these were deemed ‘significant’ (>1000l CH4/h), causing serious financial losses and safety concerns; half had only minor leakages (< 100l CH4/h); while the rest were deemed ‘medium’ (< 1,000l CH4/h). In most cases, more than one leakage type was present.
Translating this to the UK as a whole could mean that 550 plants are currently at risk; with 137 in danger of a serious financial or safety breach. Furthermore, if each of these 550 plants was to leak an average of just 0.5% of their capacity, it could equate to a potential loss of 37 GWhe-e a year, resulting in 6000 tonnes of methane escaping into the atmosphere annually
- Cable grommets (where a submersible stirrer cable passes through the digester wall)
- Flange connections
- Viewing windows
- Pipe penetrations
- Carbon filters
- CHP Exhaust emissions
- Pressure relief valve
- Open chambers
- Any areas where maintenance is carried out
Identifying a leak is a simple and affordable process which can help prevent a serious incident from occurring, and a gas leakage detection service should form part of any responsible plant operator’s ongoing maintenance programme.
Inspectahire's leak detection service covers a full AD plant survey using a GF320 OGI camera with methane-sensitive gas monitor. GF-Series cameras allow enable large areas to be surveyed quickly and effectively, detecting small emissions within large complexes.This Inspectahire service includes:
- Survey of all tanks, CHP, gas holders, flares, boilers, biogas upgrading equipment, roof membranes, pipes and flanges.
- Analysis and qualification of emissions found were possible.
- A report with images, videos and severity table.
The best times to conduct a detection survey are:
- At the start of full operation
- After significant maintenance work
- Where the feed-to-gas conversion is lower than expected (and the biology remains stable)
- Where there is a smell biogas.