Abstract: A composite board for use as backerboard for tile, the board including a mesh layer with a mesh fabric, a mat layer with a mat fabric and a polystyrene layer disposed between the two portions where a non-shrinking cement compound saturates and connects the two outer portions with the polystyrene substrate. The composite board's mesh layer incorporates a stretchable mesh which in conjunction with the polystyrene substrate and the non-shrinking cement compound supports standard fasteners used in the home-building industry along with providing a suitable tile adhesion surface. The mat layer incorporates a fiberglass mat which provides high rigidity as well as being suitable for contact with an inner wall or studs. The combination of materials provides a backerboard that is light weight, rigid, economical and easy to build with.

Abstract: Water from existing clarifier tank is pumped to a centrifugal separator where solid particles are removed. A bypass valve is disposed between the outlet of the separator and the inlet of the pump to keep the separator operating at high velocity even when there is little or no demand for processed water. A vortex breaker is provided at the sludge outlet of the separator to prevent solid particles from being carried to the processed water outlet to the separator. A valve is provided at the outlet of the vortex breaker to prevent vacuum lock when the pump is turned off, and a priming valve is provided to prime the pump. A float tank and check valve may also be provided for expelling trapped air from the system. Two or more centrifugal separators may be employed in parallel when a higher volume of processed water is required.

Abstract: A pump supplies water from a clarifier tank to a centrifugal separator, where solid particles are removed, and then to wash spray heads. A return or bypass conduit with a pressure-operated, modulating one-way valve permits water to pass from the outlet of the separator to the inlet of the pump in sufficient volume to ensure that the separator will operate at high velocity even when there is little or no demand for processed water at the spray heads as well as to recycle centrifuged water to further clean it. A float tank is coupled to and extends from the return conduit for enabling any trapped air to be expelled from the system. In addition, an air-bleeding conduit with a one-way check valve therein is placed in parallel with the return conduit to permit air flow in the direction opposite to that allowed by the valve therein to enable air to be removed from the system, especially when the pump is primed by supply of additional water thereto.