Gas giants

New gas analysers have allowed a waste to energy plant in West Sussex to achieve its target of 85% operating time.

The plant, owned and operated by Enviropower in Lancing, has a 5MWe capacity, burning around 60,000 tonnes a year of biomass fuel derived from construction and demolition waste.

Built in 2008, the plant uses an ABB ACF-NT multi-gas analyser on each of its two combustion lines.

Used to measure all the gas emissions from the plant, their data is sent to an emission reporting system, allowing Enviropower to prove that it is meeting the requirements of the Environment Agency.

The ACF-NT emission and process monitoring analyser offers continuous, quantitative and selective measurement of numerous gasses, including HCl, HF, H2O, CO, CO2, SO2, NOX, NH3, N2O, O2, TOC and NMHC (non-methane hydrocarbons).

The product achieves high stability, accuracy and reliability through proven FTIR technology.

It also offers integration and display of signals from other instruments, including data on dust, mercury, flow, pressure and temperature.

“We were looking for a big name supplier,” says the plant’s general manager, Mick Adams.

“We wanted an organisation that had experience in the industry and which could offer the kind of service support we needed.

“Because our operation is permit based, we have to meet certain criteria. One of these is the use of equipment that complies with the requirements of the Environment Agency’s MCERTS standards.

”Our permit specifies a minimum oxygen content of 11%, which will shortly reduce to 6%, so it was important that the analysers had the flexibility to adapt to changing regulations. ABB liaised closely with the Environment Agency to ensure the solution provided to Enviropower would meet their needs,” says Adams.

“There were a number of large companies that could meet our needs but none we felt so comfortable with. All the people we met at ABB were very helpful and easy to deal with.”

Reliability of the analysers was also key to the selection of ABB for Enviropower, says Adams, because the ABB analysers need servicing only once every six months.

“If the analysers are not online we cannot produce power, so it was vital that reliability was high and that servicing was kept to a minimum.”

Steve Donnelly, analytical sales specialist for ABB, says: “We conducted a pre-design consultancy phase to ensure that the analyser solution would fit onto the site, could connect to the plant control systems and would be maintainable in-situ.”

”ABB provides us with very good support,” says Adams.

“We are very happy with the service regime which is very well organised and gives 24/7 support through a dedicated helpline.”

This support also extended to helping complete the project when the original contractor ran into difficulties towards the end of the contract, says Adams.

“ABB stepped up to ensure that the contract could be completed and took on the financial burden of seeing the project through to completion,” he says.