An investigation into DOW and MOND indices with fuzzy logic based on fire and explosion risk assessment in Iran oil refinery

With regard to a study on accidents in chemical industries, approximately 2.3 percent of the damage is related to explosion. The explosions happen in no time and there will be no opportunity to avoid them, therefore, explosion damage is more than fire damage. Fire and explosion risks always exist in gas and oil industries. The present paper intends to assess fie, explosion, and toxicity risks based on MOND and DOW indices, and then compare the indices with each other regarding fuzzy logic. The last version of fire, explosion, and toxicity index introduction was used in the process subunits in northern Iso- max unit of Tehran oil refinery. The important process subunits in northern Iso-max unit were recognized based on process effective factors such as pressure, temperature, and value of the materials. In the next step, factors affecting fire, explosion and toxicity index (TF& EI) were recognized and estimated. Moreover, (TF& EI) index was calculated for each subunit, and then time duration and real rate of damage and their effects were studied. The results indicated that 6 subunits out of 8 had high fire, explosion and toxicity degree of risk. One of the subunits had high and the other had medium degree of risk. 2V432 catalytic conversion reactor is the most important subunit of northern Iso- max unit; it has the highest rank of fire, explosion, and toxicity risk; its fire risk equals 232.4 and its toxicity risk equals 49.3. 2H432 reactor feed heater with 124.8 degree of fire risk and 7.2 degree of toxicity risk has the minimum fire risk and the medium toxicity risk, respectively. The research shows that fire, explosion and toxicity index is a proper method to determine the most and least hazardous points of an industry. Catalytic conversion reactor is the most critical unit regarding fire, explosion, and toxicity.

Keywords:

Risk , DOW , MOND , Fuzzy logic , Toxicity , Fire , Explosion