BVF

water and sewage systems for treating water and sewage comprising a lagoon to hold the liquid, a cover for the liquid in the lagoon and gas removal equipment; namely, pumps, conduits and valving; anaerobic treatment systems for treating sludge comprising a lagoon to hold the sludge in liquid form, a cover for the lagoon filled with sludge and equipment; namely, pumps, conduits and valving for removing the generated gas from the treated sludge; and biogas recovering systems for aerobic or anaerobic treatment plants comprising conduits for removal of the gas from the treatment systems and covers for the treatment systems designed to capture the escaping gas and directed to the conduits