Study On The Recovery And Utilization Of Interstage Waste Heat Of Compressor

Under the background of global energy crisis, the improvement of energy efficiency, rational allocation of resources has became a unavoidable problem for each country. As a large synthetic ammonia production country, China produces tens of millions of synthetic ammonia, which means huge energy-saving potential in synthetic ammonia industry. Based on a target enterprise with annual synthetic ammonia production of 0.24 million, this thesis studied the feasibility of waste heat utilization with in gas in multistage compression section. Moreover, the waste heat utilization scheme was designed. The main researches were as follows:1. A novel process improvement scheme was proposed: a heat exchanger was installed between each stage of compressor, the 95 degree Celsius desalted water from cooling syngas was used to drive the newly installed lithium bromide absorption refrigeration machine, and the 8 degree Celsius cooling water from former section was used to cool down the inlet gas of the compressor.2. Using Aspen Plus software solution before and after the improvement are analyzed in numerical simulation, the improved process is obtained by analysis and calculation of waste heat, and the process of the specific parameters of each module.3. Completed the numerical simulation of the libr absorption chiller. The waste heat was completely utilized by Sanyo LCC-61 D large temperature low temperature water type lithium bromide absorption type refrigerating machine.4. The heat exchanger at the prime stage gas inlet of the compressor was designed based on the novel scheme.5. Determine the scope of work of the improved scheme, The best condition and so on.6. Both the energy efficiency and economical analysis on the novel scheme was performed. Comprehensive analysis was performed on aspects of cooling water saving, production efficiency improvement earnings, new equipment invest and maintenance cost, ect. Compared with the original scheme, the novel scheme could save water 80 kilograms per second, each ton ammonia energy saving 115 kilowatt-hour, the investment recovery cycles of the novel scheme was approximately 7.5 months.