Measured Effects Of Liquid Distribution On Compressor Performance During Wet Gas Ingestion

Abstract

Upstream production of natural gas is commonly a mixture of both liquid and gas hydrocarbons that is separated before boosting the gas or liquid flows to higher pressure for transport. The gas-liquid mixture is known to affect the compressor performance, but it is not known if the distribution of the liquid entering the compressor affects the maximum amount of liquid that the compressor can safely ingest. The work presented in this paper determines if liquid atomization affects the compressor operation or influences the amount of liquid that can be safely ingested by the compressor, compared to non-atomized liquid. To determine the effect of atomization on compressor performance, three injection methods are used to characterize the performance for atomized and non-atomized flow. Non-atomized flow is generated by injecting liquid far upstream of the compressor to allow a natural two-phase flow regime to develop before entering the compressor. Atomized flow is generated near the compressor suction flange using liquid pressure to generate large droplets on the order of 2,000 m and gas-assisted atomization to generate droplets at least an order of magnitude less than the large droplets (100 m). Results of the work are reported in this paper to include compressor performance measurements for two rotation speeds and a range of liquid and gas flow rates. In addition, the control of the compressor during wet gas ingestion is demonstrated through movement of the compressor on the flow map. Finally, high-speed flow images of the liquid entering the compressor are qualitatively shown to illustrate the difference in injection method.