Application and Suggestion of Environmental Protection Testing Technology for High Sulfur Gas Reservoir in Chuanxi Gas Field

Abstract

Western Sichuan gas field is located in the developed area of western Sichuan and the main gas layer is characterized by high sulfur content, hydrogen sulfide content averaged 5.15%. In the drainage stage after the implementation of stimulation measures, influenced by residual acid and hydrogen sulfide, strong odor diffusion occurred, causing environmental problems in the sur-rounding area. At the same time, the flowback liquid contains high hydrogen sulfide, which is easy to overflow during transportation, forming hydrogen sulfide poisoning hidden danger. Generally, the neutralization method of adding sodium hydroxide solution in the blowpit can no longer adapt to the actual situation on site. To further eliminate the environmental and safety hidden danger, through continuous improvement on the spot on the implementation of “process with sulphur removal agent, in addition to flavor agent + injection with spray nozzle spray fire”, “online real time in addition to sulfur + feed nozzle spray + nozzle spray fire” two kinds of technology application effect of contrast, finally choose “acid condition real-time desulphuration process + put nozzle ignition” process, at the same time for sulphur removal agent and alkali liquor filling parameters, a set of environmental protection testing technology for high sulfur gas layer in west Sichuan gas field has been preliminarily formed. At present, the field has basically eliminated the influence of peculiar smell, the treatment index of flowback liquid reaches the PH value of 7~9, and the H 2 S concentration is less than or equal to 5 ppm, which can meet the requirements of directly into the tank for transportation.