Common Suction Accumulator & Accessories



The common Suction Accumulator known as “Knock-Off Drum” is installed before the ammonia compressor to avoid liquid ammonia entering into the ammonia compressor. The vapour from the process skid is routed through this suction accumulator to the compressor.

Along with Ammonia vapour liquid, ammonia particles also will be carried away, and these liquid ammonia particles will need to be separated from entering into the compressor. The hot liquid ammonia from the receiver shall be circulated through the coils provided inside the suction accumulator.

Due to temperature difference, the liquid ammonia collected in the suction accumulator gets evaporated. Incidentally if the liquid ammonia accumulates till top of the coil, then the level switch provided will activate the heater until the level of liquid ammonia comes down.

Common Suction Accumulator shall comprise of the following:



A vertical CS vessel, sized for 36TR refrigeration capacity at -20.5⁰C evaporation temperature, and 40⁰C condensing temperature.

Coils provided inside the vessel for the circulation of hot ammonia liquid for the heat transfer.

Inlet & outlet nozzles 4”size with one number 4” valve at inlet.

Demister pad just before the top dish is installed to stop liquid molecules if any, and allow ammonia vapour only to pass through.

Two sight glasses, one just above the top of the inside coil, and another at the top of the demister pad.

2 number liquid level switches are installed. One just above the top of the inside coil, and other one just above demister pad.

Electrical heater at the bottom of the coil in a thermo well.

One set of electrical heater controls provided. This heater will get actuated only when the liquid ammonia in the suction accumulator reaches to the level of 1st levels switch installed just above the top of the coil. Provision shall be made to put off the compressor, if incase the level of liquid ammonia reaches till the 2nd level switch