Process Simulation And Analysis Of A Million T/a Indirect Coal Liquefaction Synthetic Oil

With the rapid growth of national economy,the energy supply has become more and more difficult to meet national consumption,and the limited oil resource has become a serious problem in oil supply.In 1993,China become a country of net imported oil,and in 2011,the imported oil reached 252 million tons with 56.5%of oil dependence on foreign market.Compared with the oil resource,China has abundant coal resource,so the development of indirect coal liquefaction synthetic oil technology is one of the important measures to guarantee the security of our country's energy supply,and it can ease the contradiction between supply and demand of liquid fuels and promote the adjustment of the holistic structure of the coal industry in China.Indirect coal liquefaction synthetic oil technology is one of the coal liquefaction technologies,and now the scale of the technology is in a 160,000 t/a of industrial demonstration phase,and the megaton indirect coal liquefaction synthetic process of industrialization will come in the near future in China.In this paper,megaton indirect coal liquefaction synthetic process route has been designed combined with the industrial demonstration and optional coal properties,the comparison and analysis on the technology of the air separation unit,the gasification unit,purification unit and synthetic unit have been emphasized,the result is obtained,according to the coal resources and process requirements,that cryogenic air separation oxygen technology,Lurgi gasification technology,Rectisol technology,iron-based slurry phase synthetic technology are reasonable.We can get conclusions by building the models of the technical units and simulating and calculating a process of one million t/a of indirect coal liquefaction synthetic using Aspen Plus simulation software.The conclusions are as follows:(1)Through simulate calculation by using Aspen Plus,we can get:lump coal consumes 3680,000 t/a and diesel oil can be produced 630000 t/a,naphtha can be produced 370,000 t/a.(2)The energy consumption analysis shows that comprehensive energy consumption of production oil is 3.86 tons standard coal,total energy consumption per RMB10,000 is 4.40 tons standard coal,energy conversion efficiency is 37.89%.(3)Through calculating carbon balance of the system-wide,we can get:the utilization rate of total carbon is 37.00%,among this,the carbon in C02 emissions contribute 42.46%,the loss' carbon during incomplete combustion and process contribute 7.61%.The emissions of CO2 can reach 4418.6 thousand per year.(4)In order to improve carbon utilized rate,the hydrogen is producted by synthetic oil exhaust,the surplus nitrogen is producted by air separation unit,the carbon dioxide coming from purification unit,are used to poly-generation urea.According to 8000 hours of annual production,the production of poly-generation urea can reach 1.36 million t/a,the reduced carbon dioxide emissions can reach 997,000 t/a,the carbon utilization rate improve 9.57%,getting to 46.57%..