Sustainable process design for heat exchanger network considering inherent safety and process economics

• Published in: Canadian journal of chemical engineering 2024-07, Vol.102 (7), p.2481-2494
• Main Authors: Athar, Muhammad, Shariff, Azmi Mohd, Rashid, Muhammad Imran, Aadil, Mahboob Ahmed, Umer, Asim, Irfan, Muhammad
• Format: Article
• Language: English
• Subjects: Ammonia; Economics; Hazard assessment; heat exchanger network; Heat exchangers; inherent safety; process design; process economics; sustainable
• ISSN: 0008-4034; 1939-019X
• DOI: 10.1002/cjce.25202

Process lifecycle has several stages, including process design covered in multiple stages. Process economics is a vital factor in finalizing the process design. Besides economics, inherent safety is an important concept contributing to sustainable process design generation. The inherent safety concept has been applied via equipment characteristics for individual equipment. Since a method considering inherent safety with equipment aspects and process economics has not been available, therefore, a new method has been proposed, namely sustainable process design for heat exchanger network (SPDHEN), to integrate inherent safety, equipment aspects, and process economics. SPDHEN uses indexing to identify the critical heat exchanger, which is then examined via hazard analysis for an explosion. For unacceptable hazards, inherent safety principles are engaged to generate design alternatives for which process economics is examined too. The final design would be inherently safer with the best profit margin. The proposed method has been studied for the ammonia synthesis loop. It is concluded that the explosion hazard has been reduced to a tolerable level by using inherent guide words with a marginal compromise on quantity of ammonia produced, that is, 0.32%. This method is straightforward and can be useful for process engineers to generate sustainable process designs for heat exchanger networks considering safety and process economics simultaneously. Sustainable process design method for heat exchanger network is developed for earlier design stages. Here, inherent safety is considered via relative ranking indexing for equipment approach. Profit is considered to define the cost aspect for design selection. In this work, process condition is the focused design error and tackled via moderation guideword. For developed method, ammonia synthesis is studied and results are compared with available research.