100 km south of Copenhagen world’s biggest membrane for biological gas has just been blown up. With the membrane the Hashøj Biogas plant near Ringsted holds world record of containers for biological gas. The container is designed to hold 12.000 m³ biological gas that covers the consumption of heating for 500 households of the nearby villages. “World’s second biggest membrane for biological gas is situated in Canada and has a capacity of 11.500 m³ “, says works manager Erik Lundsgaard of Hashøj Biogas to the PVC Information Council Denmark. “It was very important for us to beat that record”, Lundsgaard says with a twinkle in his eye.
 
The gas balloon in Hashøj consists of a polyester armoured double membrane coated with PVC on both the inner and outer surface. A white, somewhat bigger PVC bubble is put around a smaller yellow PVC bubble in the inside. The outer membrane is stable, while the inner membrane is flexible. Director Poul Seest Egly of Dafeta Trans, who is the supplier of the membrane, says to the PVC Information Council Denmark that PVC is the only applicable material for the purpose. The material resists all outer effects that the membrane will typically be exposed to, e.g. sun, wind, snow and rain. And the membrane is impervious to odour, which the PVC secures. The hard wearing of the material is also important. The container is expected to last for at least 20 years.
 
In Hashøj Biogas they receive biomass in form of farm animals’ dung and organic waste from slaughterhouses, dairies and households. The biomass is being transformed in the balloon, where bacteria have optimum growth conditions. The production of biological gas brings along a reduction of the outlet of greenhouse gas on a whole.

Photo: PVC Information Council Denmark