High-pressure methanol synthesis case study: safety and environmental impact assessment using consequence analysis

The purpose of this paper is to investigate the estimated people's fatalities percentage due to methanol reactor incident from a newly proposed plant in Perak, Malaysia. This work investigated the possibility of (1) various events occurring in term of toxicity, thermal radiation, and overpressure, and (2) the fatalities percentage when these events occurred due to the release of chemical mixtures from the reference plant, which has 42 m(3) reactor volume and operates at 76.4 bar; and three reactor scenarios in which the reactor volume is reduced to 7.6 m(3), while operating pressures are 76.4, 150, and 300 bars. HYSYS software was employed to simulate the process and obtain the mass density of the mixture, mass fraction, and volume fraction, while ALOHA and MARPLOT software was used to calculate the amount of toxicity, thermal radiation, overpressure and area affected. The methanol reactor contains a mixture of hydrogen, carbon dioxide, methanol, carbon monoxide, and water, where only water is not considered hazardous. Release of chemical mixture via three-hole size scenarios, 10 mm, 25 mm, and 160 mm was proposed, and the simulation was carried out. Results showed that reference plant and plant 300 bar exhibit the highest fatalities percentage for overall and reduced reactor volume (15.7% and 11.2%), both caused from the release of carbon dioxide at night through a 160 mm hole leakage. This study can be used to suggest the best location for the methanol plant to be built to avoid any deaths to people living surrounding area.

Automated summary

This study investigated the estimated people's fatalities percentage due to a methanol reactor incident from a newly proposed plant in Perak, Malaysia. Simulation using HYSYS, ALOHA and MARPLOT software showed that the reference plant and plant at 300 bars had the highest fatalities percentage, caused by the release of carbon dioxide through a 160 mm hole leakage.