Steel and concrete tanks who are used for the storage of Biogas and therefore are covered by the biogas double membrane roof. The biogas double membrane roof exist from a inside membrane from biogas persistent foil and a weather persistent outside membrane. (roof) Both membranes are placed on the tankwall with stainless steel strips. On the inside a wooden centre column with a net and tensioned bands hold the double membrane roof. Standard the roof is made for lower pressures -0.5 en Pmax 5 mbar, on request higher pressures can be designed. We deliver several volumes depending on diameter tanks up to 32 meters.

The biogas inside membrane is very gastight and gas resistance and will standard be made from a foil around 750 gr/m² up to 1050 gr/m². The foils used for the inside membrane show a methane gas leak proof < 350cm³/m² up to < 300cm³/m² The cover membrane (roof) foils are a good UV-resistance and have a long lifetime, and are flexible at lower and higher temperatures.
All materials who are in contact with the gas or liquid are made from stainless steel. The ventilator is a Atex zone stainless steel one. The safety valve is needed on the tank to release the gas if higher pressures than allowed will occur. Other inside membrane are possible.

Depending on the kind tank that needs to have a biogas double membrane roof, the roof will be placed on the top of the tank wall. A hard wooden centre column will be placed in the middle of the tank at the same height as the tank wall and fastened with tensioned straps. Over the straps a net will hold the inside membrane when there is no gas, and also will capture the methane. The biogas membrane roof will be rolled out over the net, and tighten to the tank with stainless steel straps. The Atex ventilator will hold the outside membrane spheroid against all weather conditions.

A safety valves needs to be installed just under the roof in the tank wall.

If there are any questions or remarks please contact us at info@isstanks.nlor give us a call at 0031 (0)512 – 58 20 58