Optimize compressor parameters for reduced inlet pressure and gas flow

L. K. Singh, Consultant, Kuala Lumpur, Malaysia Produced gas pressure at the wellhead normally is not sufficient to allow export for sales and further treatment. Therefore, an export gas compression system is required, with a centrifugal compressor being the most suitable for variable sales gas demand and near-constant export pressure. Normally, the export gas centrifugal compressor works well under constant inlet pressure. Compressor operation is challenged when the gas well reservoir pressure is reduced (due to reservoir depletion), and when the full well steam (FWS) water cut increases and the gas fraction in the FWS decreases. Consequently, inlet pressure to the compressor is reduced.