For use in gas cooling applications at a number of refineries in Turkey, HRS Heat Exchangers Ltd. will supply 16 K Series multi-tube heat exchangers to Gas Compressors Ltd., Tonbridge, England. The exchangers will be used to cool recovered high temperature, high pressure flare-gas to knock out liquids and improve gas compressor efficiency across three refineries.

Gas Compressors Ltd. designs and commissions large- and medium-sized, custom-built gas compressor and booster packages. According to HRS, GCL selected the K Series shell-and-tube heat exchangers because they provide efficient operation at high temperature and high pressure. The units will be assembled into the compressor packages being manufactured by GCL in the United Kingdom. Two compressors will be used on each of the four process streams ? with two heat exchangers per compressor ? to provide precooling and interstage cooling for the application.

Critical design considerations for the heat exchangers included the required thermal duty for gas cooling, condensation of liquids, minimizing pressure drop and the overall size of the package. The units, manufactured by HRS in India to ASME and TEMA R code, were carefully designed to meet all requirements and provide efficient service. The heat exchangers have an internal corrugation that creates turbulence in the flow without impeding it. The turbulent flow helps improve heat transfer because it mixes the fluid; conversely, laminar flow relies solely on the thermal conductivity of the fluid to transfer heat from the middle of the flow to the heat exchanger walls. The flare gas passes through the tube side of the heat exchanger and cooling water on the shell side. As the gas cools, liquids are forced out to ensure better compressor performance and an overall more efficient process.