IMPROVEMENTS TO SEALED RESERVOIRS FOR METHANATION OR STORAGE IN CORROSIVE ATMOSPHERE

摘要

The invention concerns a sealed reservoir for biomethanation of liquid effluents such as sludge, manure, urban or industrial waste, or to be stored in a corrosive atmosphere, comprising a concrete apron (12), a steel or concrete pressure envelope (12) and a sealed and corrosion-resistant dome (14), consisting of a double membrane: one inner membrane (15) defining, with the liquid effluent surface contained within said pressure envelope, a tight chamber (13) for receiving the biogas resulting from biomethanation, or said corrosive atmosphere and, an outer membrane (16) enveloping the inner membrane and which, when under excess pressure, applies a predetermined pressure on the biogas volume or the corrosive atmosphere, contained in said chamber (13). Said sealed reservoir is characterised in that said inner membrane (15) is extended downwards by a skirt (18), whereof the lower portion is immersed beneath the level of the liquid effluent contained in the reservoir so as to ensure tightness in the chamber (13) delimited above said level, said skirt being fixed, over its whole periphery, below the liquid effluent (17) level, on said pressure envelope (12) inner wall, via a joint (19) pressed against said wall, by means of stainless steel flat irons (20) fixed in the wall.