The accident at the Isotec Company, which occurred in 2003 in Ohio, United States of America, will be presented as part of the thesis. It is an accidental event of elevated pressure and subsequent rupture of a process unit of nitrous oxide, a toxic, colorless gas with a strong odor, which destroyed an underground distillation column, injuring one worker. The thesis summarizes the findings of the CSB commission of inquiry into the resulting high pressure accident and presents guidelines for the prevention of such accidents. I focused on the Pressure Directive 2014/68/EU and the HAZOP analysis.
In order to reduce accidents in industries as much as possible experts have developed different methods. With help from these methods, systematic and organized solutions can be found based on deviations or defects. With the help of the sketch attached in the CSB repost and the HAZOP method, I analyzed the causes and consequences of individual component failures in the experimental part. The HAZOP method is aimed at finding and preventing problems already in the initial stages. It is a technique for the structured and systematic study of a planned or existing system, procedure and process, used to identify any deviations from the normal operation of the system, their causes and any associated hazards and problems. To implement this method, we must first divide the system, process or procedure into smaller elements (parts), determine the appropriate parameters, and use guiding words in combination with them. Afterwards, the causes for each keyword and parameter, as well as the consequences or problems, are determined. It is necessary to define measures (what, who, when). It is very important that the discussion and findings are recorded and the process is repeated for each element of the system.
Based on the article, I found that the investigation of the accident showed quite a few errors in safety management of the company. In my thesis, I will present two approaches for identification of dangerous events: the use of questionnaires and the HAZOP method. I preformed both analyses, and based on the results concluded, that it is imperative to add additional safety elements and processes for such a distillation system. It is necessary to connect the column insulation jacket pressure gauge to the safety shutdown of the distillation process, install a safety valve on the distillation column insulation jacket, install a temperature and pressure gauge of the cooling medium of the heat exchangers, and install a safety plate on the distillation column and reactor.
|