Abstract: A gas venting floating cover for a liquid container, the cover including a continuous sheet of flexible material adapted to lie upon the liquid in the container in coextensive relationship therewith for attachment to the container sides in fluid tight relationship. Flotation blocks are attached to the cover to define gas collection spaces for receiving gas evolving from the liquid. The flotation blocks include first and second strings of blocks transversely spaced apart to define a longitudinal passage, certain of the blocks of each string being longitudinally spaced-apart to define transverse passages in communication with the longitudinal passage. A gas collection conduit is attached to the first and second strings in coextensive overlying relation to the longitudinal passage and includes gas admission openings, and a plurality of transverse straps extend between the first and second strings of blocks to constrain them against separation under the weight of the gas collection conduit.

Abstract: A gas venting system for a liquid storage reservoir having a floating cover comprising a sheet of flexible material lying upon the liquid and attached to the reservoir sides. Elongated blocks of flotation material are attached to the underside of the cover and buoy the cover in such a way that the edge margins of the blocks and the adjacent portions of the cover define downwardly open collection spaces. A gas collection manifold in communication with these collection spaces receives and carries away gases collecting in the collection spaces. In one embodiment the flotation blocks include transverse conduits affording communication between the collection spaces on opposite sides of the blocks, with the transverse conduits being in communication with the gas collection manifold.

Abstract: A floating cover for a liquid storage reservoir to prevent contamination of the stored liquid. The cover includes a continuous sheet of flexible material overlying the liquid and attached to the upper periphery of the reservoir, the area of the sheet being greater than the area encompassed by the upper periphery of the reservoir. The cover further includes floats in the central portion to float it higher than the peripheral portion whereby the excess material in the peripheral portion forms a depending rainwater collection sump..Iaddend.