Mechanical refrigeration compressors are designed to compress vapor and not liquid. Very small amounts of liquid will often pass through without harm but in sufficient quantity mechanical damage will occur. The term “slopover” is used by the industry to refer to liquid refrigerant entrained in the suction gas traveling to the compressors.
The best method of removing the slopover is to install a suction accumulator, which is a vessel that is designed to separate liquid from the gas. It is designed to reduce the velocity for a long enough time period for the liquid to drop out by gravity.
Typically, a suction accumulator consists of a vessel that is ASME coded for 175 psig working pressure and registered with the National Board. It is usually equipped with internal baffling to direct the wet gas toward the ends of the vessel allowing the heavier drops of liquid to impinge on internal surfaces. It is equipped with a high level safety float switch with isolation valves, an oil drain valve and a pressure relief assembly with a three-way valve and two appropriately sized relief valves.