Process Risk Assessment For Liofol Polyester/Polyurethane Batch Process

Combined with Hazard and Operability (HAZOP) study and Risk Matrix, Henkel’s Process Risk Assessment procedure was used to analyze risks in the Liofol Polyester (PE)/Polyurethane (PU) process through Concept stage risk assessment and Basic risk assessment. and also the PE section, divided into charging, reaction and discharging segments, was analyzed through Detailed risk assessment where chemical safety engeering models, as well as the Fire Triangle concept, were utilized to study the process solvent ethyl acetate (EA), as an example in the discussion, for the source models and fire/explosion risks of the section, providing useful reference for further risk prevention of the process. After the concept risk assessment of the Liofol PE/PU process, it was discovered that there were many toxic and flammable materials in the process, presenting relatively high toxic and fire/explosion risks for the process.lt was indicated by the result of the basic risk assessment that fire/explosion risk was the highest in the process, thus needing more implementaion of anti-static and inerting measures, along with a complete relief plan to ensure equipments and piping safety. It was found in the result of the detailed risk assessment of the PE section that mistaken charging, coded as "flow:as well as" in HAZOP, and any PLC failure in the section should be well prevented by existing and recommended safety engineering design and a firm safety management with leading indicators to reduce the risk. Moreover, it was showed that the EA, a potential fuel, deserved more strict leakproof control and interlocking after source models and fire/explosion analysis; and it was necessary to conduct special anti-static technology for the solid handling system to prevent the forming of ignition source in acid dust, ultimately reducing the toxic and fire/explosion risk of the process.