Abstract: A settling tank for separating an emulsion with a known volumetric percentage of oil includes lower and upper settling chambers. The emulsion is settled by gravitational means and can be aided by demulsifying agents. Once settled, a layer of oil floats on top of the water. The volumes of the lower and upper settling chambers are configured so that all of the oil settles within the upper settling chamber. The oil can then be drained from the upper settling chamber leaving only clean water in the tank structure.

Abstract: A large slide valve member concentrically mounts a small slide valve member or slide stop at one end thereof proximate to a helical screw rotary compressor discharge port with the small and large slide valve members movable as a unit for varying the built in volume ratio of the compressor. The small slide valve member is shiftable independently of the large slide valve member to vary the capacity of the machine. A large diameter cylinder fixedly mounted to the end of the compressor casing remote from an outlet port slidably mounts interiorly a smaller diameter cylinder fixed to the large slide valve via a spindle. The small slide valve is fixed to one end of a piston rod which extends through a bore within the large slide valve member and the spindle and terminates internally of the small diameter sliding inner cylinder and has fixed thereto a piston.