A small reservoir, typically in the range of 2 to 5 gal (7.57 to 18.93 L), used in a dual mechanical sealing system, where no leakage to atmosphere is tolerated. The complete sealing system consists of dual mechanical seals with a buffer fluid circulated between the seals. The buffer fluid, which is partially contained in the seal pot, is either vented to a flare or pressurized depending on the application. In an unpressurized system, primary (inboard) seal leakage will result in product leakage into the buffer fluid.
Also known as a Buffer Fluid Tank.