Patent ID: 11708691

Abstract:
An apparatus having a layer of fats, oils and grease (F.O.G) on water includes a tank having an inlet and an outlet. The inlet connects to a source of F.O.G.-laden effluent and the outlet connects to a sewer pipe so that the outlet defines a normal static water level for F.O.G. and effluent in the tank. A sensor mounted above the static water level determines a distance from the sensor to a top of F.O.G. within the tank, so that a thickness of the F.O.G. in the tank can be determined. If the sensor is LIDAR, sensing may be at about 940 nm. When the F.O.G. is sensed to be above a threshold, the apparatus generates signals to remove the F.O.G. Ultrasonic sensing may be used. Preferably, the sensor is mounted far enough above the static water level so the distance between the sensor and the liquid surface is filled with air. More preferably, the sensor is far enough above the static water level so that the top of the F.O.G. does not touch the sensor even as the top of the F.O.G. rises above the static water level.