Abstract: An automatic oil-water separator which separates wastewater into oil or grease and water fractions is disclosed. The separator does not include any mechanical pumps in its structure and therefore does not generate oil or grease and water emulsions which are characteristic of separators using pumps and which are very difficult to separate. The separator is constructed without moving parts, filters or coalescing plates and operated without the addition of chemicals or the use of electricity.

Abstract: The automatic grease separator receives wastewater containing grease and other light fluids, separates the water portion from the light fluids portion, and stores the light fluids portion. A computer is used to control the operation of separator functions including automatic transfer of light fluids from the separator to grease containers and automatic shut-down of the separator when its capacity is exceeded. Warning devices which indicate malfunction or the need for maintenance also are controlled by the computer. The grease separator uses grease level sensors based on capacitive level sensing. These sensors are insensitive to coating of the sensors by grease and oil. The grease and other light fluids are maintained in a fluid phase by the thermostatic-controlled addition of hot water. This feature provides an added element of safety by eliminating the need to heat the separator by a resistant heater which introduces the possibility of a grease fire.