Development and evaluation of a combined control device for H2S leakage in high-sulfur natural gas plants

Abstract

Hydrogen sulfide (H₂S) is widely present in industrial manufacturing processes, particularly in the petrochemical industry. In some Chinese natural gas treatment plants, natural gas features high H₂S concentration and pressure. Once leakage occurs, it will severely threaten workers' safety and health. Due to the harm of H₂S and the lack of prevention and control devices, H₂S leakage may cause unacceptable losses. In order to prevent and control the loss caused by high-sulfur natural gas leakage, this paper first compares the absorption rate of H₂S by single sodium carbonate (Na₂CO₃) lye and modified lye through absorption experiments. 3.0 % Na₂CO₃ and 0.6 % H₂O₂ mixed alkaline solution was preferred as the scavenger. The mechanism and effect of the prevention and control device were studied by similar experiments. Finally, a set of combined prevention and control devices was designed and verified in the purification plant. The results demonstrate that: (1) The absorption rate of H₂S by the preferred scavenger reached 95 % within 90 min; (2) The prevention and control functions of the combined prevention and control device include blocking, absorption, reverse propulsion, and others; (3) The combined prevention and control devices have good protection function and can form a safe area behind the partition wall; (4) The device's reaction time (<5 s) is shorter than the 12-s threshold at the IDLH concentration diffusion level. This research provides theoretical and technical guidance for H₂S leakage control.