Investigating the Impact of Wash Water Pump Rate on the Efficiency of Desalting Process of Crude Oil, a Case Study of X-Field in Iraq

Abstract

Desalting is an essential process in the oil industry to remove salts from crude oil. These salts, which include fine saline water droplets and salt crystals, can have a significant impact on the crude refining process. If left untreated, they can foul heat exchangers, block pipelines, cause scales, corrosion, foaming, plugging and affect the overall performance of other equipment. To avoid these salt-related problems, it is crucial to remove salts from the crude oil, This paper presents a case study of the effect of wash water pump rate on the efficiency of the desalting process for crude oil in the X-field in Iraq. The desalting process was evaluated based on the wash water pump rate. Crude oil samples were collected downstream of the desalter at various wash water flow rates, on weekly basis for about ten weeks, and the average salinity were measured in parts per million (ppm). The results of the investigation show that there is an inverse relationship between the salinity of the crude oil and the wash water pump rate. As the salinity of the crude oil increases, the wash water pump rate decreases. At wash water pump rate of 6 m3/hr. and below, the salinity of the crude oil exceeds the 30-ppm export specification; implying that a lower wash water pump rate leads to inadequate desalting of the crude oil. The study also unraveled the causes and consequences of inadequate wash water pump rate such as: clogged inlet or outlet, insufficient power supply, passing valve, worn-out or damaged impellers, mechanical failure, piping issues, sealing problems, and increased operational costs. To optimize the wash water pump rate, a procedure was also developed in this study. This method addresses the identified causes and consequences of an inadequate wash water pump rate in effectively desalting crude oil. This study has unraveled the importance of the wash water pump rate in the desalting process and t highlights the need to maintain an optimal pump rate to effectively remove salts and avoid associated problems in the refining process.