Health, Safety and Environmental Considerations for Process Synthesis

Following this approach to assessing health, safety and environmental risks can steer engineers to consider more inherently safe process options earlier in process synthesis During process synthesis in the chemical process industries (CPI), engineers make decisions that determine the inherent health, safety and environmental (HSE) risk level of a process. This article proposes a simple approach for identifying and assessing the major HSE hazards during synthesis. Understanding the risk level during synthesis enables the engineer to consider inherently safer designs (ISD) while developing the flow sheet. If risk levels are not considered during synthesis, higher risk processes will result, because decisions are hard to change once the flow sheet has been finalized. Most of the resistance to process design changes comes from trying to avoid the need to repeat expensive research and development work, as well as avoiding schedule delays. To understand the value of ISD, consider the Bhopal, India incident where, in 1984, an accidental release of the chemical methyl isocyanate (MIC) occurred at a facility for manufacturing the insecticide Sevin. MIC, an intermediate in the production process for Sevin, is a highly toxic chemical. A National…