Bowman exhaust gas heat exchangers are at the heart of a CHP solution to turn sewage slurry into valuable heat and power.

Situated on the shores of Lake Balaton, Siofok City is a major Hungarian tourism destination that has grown significantly in recent years. However, this success has brought certain problems. The expansion of tourism has put pressure on the city’s infrastructure, requiring significant investment in water treatment.

Handling ‘renewable energy’ with care
It was decided to create a new water treatment facility that would operate in conjunction with the existing plant, to increase the processing capability of the city’s infrastructure. One of the key drivers was that the new plant would be capable of handling CH4 methane gas, which would be produced as a by-product of the slurry from the Anaerobic Digestion (AD) process.  Although CH4 is a renewable energy source, it is a potentially hazardous gas, having an effect on the atmosphere that is 21 times more harmful than CO2, so it was vitally important to burn this gas within a CHP process, rather than let it escape to atmosphere.

Generating power and recovering heat energy
A packaged CHP solution was developed, based around two CH4 gas fuelled generating sets, to convert the methane gas to electrical power, plus two Bowman 8-60-3742-8 exhaust gas heat exchangers to recover valuable heat energy from the engines exhaust stream.

From receipt of the order, Bowman built, tested and shipped the exhaust gas units in just four days to meet tight delivery requirements.

Valuable ‘free’ energy source
The solution is a ‘win-win’ outcome for Siofok City, as the CHP system converts a potentially hazardous by-product of the water treatment process, into a renewable energy source. Heat and power are produced at no additional cost, in terms of fuel usage and this valuable ‘free’ energy can be either utilized within the water treatment plant itself, or sold on the open market.