Compressor inlet flare vent valve

The gas that is released through the vent is definitely gas that can no longer be used; it is usually released when the pressure becomes too high. Compressors have specified parameters for each pressure level during operation, and it is important not to exceed the inlet pressure limits stated in the manual. Each compressor has a limit on the piston force required – the higher the pressure, the greater the force needed, and once this force reaches a certain level, problems arise with the compressor. Therefore, venting is carried out when the pressure exceeds the compressor’s operating requirements. You might worry that the gas from the vent could be drawn in, but that’s not possible; as long as there isn’t negative pressure, nothing will be drawn in. You should always remember that pressure moves from higher levels to lower levels, and as long as there is no negative pressure somewhere ahead, there will be no problem

The compressor inlet flare vent valve is used to release the gas in the compressor inlet section when the compressor is shut down for maintenance; hence, it is connected to the flare. Of course, it must be closed during normal operation. If it is opened during operation, it’s equivalent to a leak, with the medium at the inlet leaking into the flare. Under normal conditions, the back pressure of the flare is very low; the pressure at the inlet of the compressor must be higher than this back pressure, so that the flare gas will not be drawn into the compressor.