Heat exchangers for biogas plants

Heatcrack Substrate Heat Exchanger – making optimal use of CHP waste heat for biogas plants

Heatcrack Substrate Heat Exchanger (WT-SWT-HC)

HeatCrack Substrate Heat Exchanger – Efficient heat recovery between the fermenter and post-fermenter

The HeatCrack optimally heats the biogas substrate between the fermenter and the secondary fermenter. The tube-in-tube heat exchanger utilises the heating water from the CHP unit for energy-efficient substrate heating. The result: thanks to the high inlet temperature into the post-fermenter, it can be operated with virtually no additional heating energy – maximising the utilisation of waste heat from the CHP unit for your biogas plant.

Thermal substrate digestion for higher gas yield

Biogas plants are often fed with low-cost, fibre-rich substrates such as manure, grass and silage. By its very nature, this biomass contains high levels of crude fibre (lignin, cellulose), which place high demands on the technology and fermenter biology. The challenge: Crude fibres are difficult for bacteria in the biogas digester to break down.

The HeatCrack solution: The substrate heat exchanger thermally treats unprocessed crude fibre components. Targeted heating breaks down cell structures and makes the substrates more readily available to the bacteria – significantly increasing gas yield.

Applications for HeatCrack heat exchangers:

For solids with an extremely high fibre content
For capacity expansion
During seasonal energy peaks
As an external heating source in the event of a failure of the fermenter heating system
Where the substrate has a short residence time in the fermenter

Further technical details:

The ‘thermal engineering tests’ carried out by our research laboratory yielded excellent results: in practice, the use of the substrate digestion system can increase biogas yield by up to approximately 5 per cent.

Download the product data sheet

Note:

The transferable heat output depends on the substrate, temperature spread, flow rate and other system parameters. A specific design is determined on a case-by-case basis.

Options:

4-tube heat exchanger – approx. 40 – 60 kW useful output
Heat exchanger with 10 tubes – approx. 60 – 120 kW effective output
Heatcrack HP (High Performance – suitable for higher heating water flow rates depending on the application) – up to 400 kW net output