불화수소 이충전 작업의 안전성 향상을 위한 긴급차단장치에 관한 연구

Abstract

Through the leakage accident of the Gumi Hube Global AHF(Anhydrous Fluoric acid), our society were seriously alarmed by the malicious effect of chemical accidents. Since then, various studies have thus been conducted on chemical accidents in many fields. Among them, it was pointed out the process system related to the tank containing hazardous materials as the cause of the leakage and measures have been devised to improve the confidence of the system with respect to the safety. The risk assessment for accidents renders the safety field derive the accident scenario and develop an improvement plan to decrease the risk of safety facilities and the impact of the damage by proper emergency response. This study was aimed to enhance the safety of the AHF ISO(International Organization for Standardization) Tank’s unloading operation by emergency shut-off devices quickly responding to chemical accidents that occurred under the same situation as in the Hube Global accident. This research investigated the annual import volume of AHF in Korea and the frequency of use and transportation volume of the ISO tank as a method of transport. The structure of the AHF ISO tank and its unloading procedure were also examined for exploring suitable emergency shut-off devices to apply. To do that, the charging stations of business site were visited in person and various types of shut-off devices commercialized for the tank lorry were studied. In the process of investigation and analysis, it was found that other chorine tanks with the similar working procedure as in the AHF ISO tank use a mechanical safety device, EFV(Excess Flow Valve). EFV’s blocking performance test as an emergency shut-off device was confirmed in the investigation report of two chlorine tank lorry accidents in Ulsan in 2018, and the EFV operation test is carried out again in this study and its performance was confirmed likewise in the emergency situation. To enhance the reliability of data obtained from actual accidents and experiments, EFV’s superior performance was justified by calculating the extent of the spread of damage using the quantitative risk assessment programs such as ALOHA and PHAST. With the safeguard described in this study applied to the AHF ISO Tank, in other words, assuming the same type of accident as the Hube Global’s, it was achieved the promptness of leakage cut-off, the time reduction in accident response, and the reduction of leakage volume. These results hopefully would help the society establish emergency response plans for leakages of hazardous materials based on accident scenarios prepared at the workplace.