Abstract: Apparatus (10) for removing sludge from a liquid reservoir, the apparatus (10) comprising buoyant float means (12), a sludge pump (24) mounted via a support arm (17) and the apparatus (10) having an upper profile so as to allow it in use to operate beneath a membrane covering at least part of the reservoir. The support arm (17) may be oscillated to move the pump in a substantially vertical plane. The buoyancy of the float means (12) may be adjusted to vary the position of floating of the apparatus (10) in the liquid.

Abstract: Apparatus (10) for collecting solids selling on the bottom of a liquid reservoir and/or floating solids, the apparatus (10) having a hollow suction head (23) and at least one outlet duct (26) extending from the suction head (23). Air can be supplied to the suction head (23) to create a suction pressure in the suction head (23) to cause settling solids beneath the suction head (23) to pass along the outlet duct or ducts (26). The suction head (23) may be connected to a collector (11) which is provided with a float (21) to support the collector (11) at the surface of the liquid, and the outlet duct or ducts (26) are connected to the collector (11) which collects the solids. The collector (11) may also have an inlet to collect floating solids.

Abstract: Apparatus for removing solids such as sludge from a liquid reservoir comprising a float, a suction head assembly carrying a pump, and elongated guides interconnecting the suction head assembly and float. The float also carries a winch for raising and lowering the suction head assembly. The guides are slidably engaged with the float and serve to indicate the depth of operation of the suction head assembly.