Analysis of Processing Accidents due to H2S in Clot Stuck Unit of one of the South Pars Refineries Leakage Using Determination of Safe Privacy Approach

Refineries are considered as the base of many accidents and incidences due to their close proximity with dangerous substances, products, and production processes. This study analyzed the consequences of H2S leakage scenario from clot stuck unit of South Pars Gas Refinery and determined the dangerous boundaries and the risk limits of this scenario.

This was a descriptive cross-sectional study. It was carried out in gas refineries of South Pars Phases 2 and 3. To evaluate the gas dispersion modality and the effectiveness of leakage scenario, the PHAST 6.53.1 software was used. To do so, firstly, the different scenarios of leakage were determined under these conditions, and then different climatic conditions affecting these scenarios were identified. Ultimately, the consequences of these scenarios were determined and these dangerous boundaries and risk limits of these scenarios for the effective and impacted areas were determined at two-level criteria of the LC and IDLH.

The findings of this study demonstrated that distance risk of LC50 for H2S Toxic dispersion for the restricted areas was 224 m and the distance risk of the IDLH for H2S Toxic dispersion for the impacted area was 386 m, respectively. Also, the results revealed that the ENI camp was in the dominant current direction in the distance of 200 m from phases 2 and 3. In the case of occurrence of leakages, many human damages and losses would happen. Consequently, it is mandatory to change the place of residence of camp inhabitants and immediately take appropriate engineering control measures.

Using the data related to hazards and considering the results of the conducted analysis, and also assessing the consequences in the frame of risk limit, the collective risks of these disaster scenarios could be determined by the use of population assessment software.