What is surging in compressors and how it can be prevented?
In centrifugal and axial compressors when the suction volume falls below a certain limit i.e. when the compressor is not getting enough volume of gas to compress, the gas from discharge side will flow back to the compressor( which would reduce the speed of compressor )and join together with the suction side to increase the volume input.
Thereafter the speed of compressor picks and it come to normal operation. But meanwhile such revere in flow will cross huge pressure gradient across the compressor and vibration thus may damage the impeller. This momentary reverse flow lapses for very short time To prevent surging we need to install an anti surging system.
The anti surging system shall have a mechanism to measure the suction flow and discharge flow time to time along with a control valve. When the suction volume falls below a certain set value a part of discharge gas will be directed towards the suction to maintain the minimum suction volume. As normally compression leads to increase in temperature the gas recycle sis taken after the “after cooler” to ensure the discharge temperature is within control.
In centrifugal and axial compressors when the suction volume falls below a certain limit i.e. when the compressor is not getting enough volume of gas to compress, the gas from discharge side will flow back to the compressor( which would reduce the speed of compressor )and join together with the suction side to increase the volume input.
Thereafter the speed of compressor picks and it come to normal operation. But meanwhile such revere in flow will cross huge pressure gradient across the compressor and vibration thus may damage the impeller. This momentary reverse flow lapses for very short time To prevent surging we need to install an anti surging system.
The anti surging system shall have a mechanism to measure the suction flow and discharge flow time to time along with a control valve. When the suction volume falls below a certain set value a part of discharge gas will be directed towards the suction to maintain the minimum suction volume. As normally compression leads to increase in temperature the gas recycle sis taken after the “after cooler” to ensure the discharge temperature is within control.
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