The Gasholder On Slab (GOS) by Alfa Ingenious Coverage is a double membrane gas storage system that can be fixed directly on a reinforced concrete slab placed on the ground, above a digester, or in other conveniently identified locations. It consists of an Outer Membrane (MEG), an Inner Membrane (MIG), and a Bottom Membrane (MFG).

All membranes are made of PVC-coated polyester on both sides, with the material category specifically selected for their respective functions and produced in the Alfa Ingenious Coverage facility according to the most advanced standards, with full internal control of the supply chain. An insufflation system continuously pushes air into the chamber between the two membranes (“Air Gap”), maintaining constant pressure on the Outer Membrane, ensuring stability against typical environmental disturbances such as wind or snow. The Inner Membrane acts as an actual gas accumulator, pressurized to allow gas capture.

The measurement of the gas level is done by measuring the height variation of the Inner Membrane through a laser detector placed at the apex of the Outer Membrane. The membranes are secured at the base by a circular system of flanges, attached to the reinforced concrete slab, with corresponding gaskets to ensure gas tightness.

The system is equipped with a safety valve in case of accidental overpressure events. Alfa Ingenious Coverage produces GOS systems capable of handling pressures up to 50 mBar.