Simulation And Analysis Of Propane Dehydrogenation Process And Its Strengthening Processes

Propane dehydrogenation to produce propene is an effective process to increase propene productivity and the value of propane. Nowadays, several propane dehydrogenation factories with a total capacity of over 6 millions tons have been declared to be built in China. Process simulation would be helpful for the process optimization. Propane dehydrogenation process(PDH), coupled propane hydrogenation and selective hydrogen combustion process (SHC) and steam propane dehydrogenation process (SDP) were designed and simulated by using Aspen Plus software. The operation conditions of the main units are determined from the simulation. It’s found that the energy consumption of separation units of the three processes is nearly same and the main energy-intensive units are compression-cryogenic separation unit and propylene rectification unit. The energy consumption of propylene rectification units of three processes are all around 35% of the total energy consumption of separation units. The energy consumption of compression-cryogenic separation units of PDH and SHC are about 50% of the total energy consumption of separation units and is about 28% for SDP. The three processes were also analyzed by means of available energy analysis and SHC and SDP are verified to have the potential to strengthen PDH. For SHC, the available energy consumption of is minimum, which is 21.8% less compared with PDH since selective hydrogen combustion reaction is used to heat the reaction streamsbetween propane dehydrogenation reactors The available energy consumption of SDP is maximum because of the available energy loss in steam generating and water separation. But with the promotion effect of steamfor propane dehydrogenation reaction, the process capacity is 23.1% higherthan that of PDH.