Assessing of some important gas condensate pollution factors along horizontal and vertical soil contamination gradients (Sarkhun's gas refinery, Bandar Abbas)

This study was designed due to the appearance of some oil pollution signs around the Sarkhun gas refinery in the city of Bandar Abbas and provided a comprehensive assessment of the current location of hydrocarbon pollution, evaluating some important pollution factors and predicting pollution distribution in the soil around the refinery. Soil samples were taken from different layers, then TOG (Total Oil and Grease) and TPH (Total Petroleum Hydrocarbon) were measured. Total suspended and soluble solids, the amount of initial oil input, and chemical and biochemical oxygen demand were evaluated. Vertical and horizontal pollutants seepages were prepared by Surfer, ArcGIS, and MATLAB. The novelty of this study was a prediction of the release of condensate gas in a specific area (depth of 24 meters of groundwater and the presence of hard surface layers). The results showed that the pollution mostly occurred in the north side of the refinery and TOG and TPH confines from 3633 and 2612 (burning pits) to 7 and 4 mg/Kg soil (south-west of the refinery) respectively, along the slope of the earth layers with more tendencies to Shour river. Abrupt increasing pollution in the east part of the refinery was attributed to the previous breakage of the sewer pipe. The results showed that the deep infiltration was up to the dimensionless depth of 0.2 and in more depth, reduced noticeably. Furthermore, TOG showed severity spreading against TPH in a similar direction. The simulation results showed that by increasing the entering water debit to burning pits, pollution spreading risk will increase, so preventing the pollution extension must be considered.