“A brief overview of the “hydrogen-free” direct liquefaction method!
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Our country is short of oil resources; the proven recoverable reserves amount to 3.6 billion tons. Based on last year’s extraction volume of 160 million tons, these reserves will only last for 20 years. International oil production increases by an average of 12% per year, while China’s annual production growth rate is only 1.5%, which is far from sufficient to meet the demand. In 2003, China imported 91 million tons of crude oil, but international oil supplies were also tight and prices kept rising. Clearly, relying solely on imported oil has placed significant pressure on the sustainable development of China’s economy, as well as posing a threat to its strategic energy security. Our country has extremely rich coal reserves, amounting to 4.6 trillion tons. Based on last year’s extraction of 1.6 billion tons, these reserves will last for thousands of years. Both coal and oil are hydrocarbons; if they can be converted into oil through specific processes, this would be an excellent way to resolve this contradiction. **It has been included in the \"863\" and \"973\" programs, and was designated as a key high-tech industry in both the \"Ninth Five-Year Plan\" and the \"Tenth Five-Year Plan\"; ultimately, intensive research and development into converting coal into oil was listed as one of the three strategic priorities for oil development. Two main process routes have been developed for converting coal into oil: 1. The indirect liquefaction method involves first gasifying coal into CO and H2, and then synthesizing fuel oil from these gases under certain temperature and pressure conditions using a catalyst. The indirect liquefaction process operates under relatively mild conditions and is hardly dependent on the type of coal. Its main drawback is the high investment cost; the infrastructure investment per ton of oil produced exceeds 10,000 yuan, which **limits its development**. 2. The direct liquefaction method involves converting coal powder directly into liquid fuel through high-pressure hydrogenation; the process conditions are quite stringent, with capital investment of around 8,000 yuan per ton of oil produced. The China National Coal Research Institute has been studying this process route, and the technology from American Hydrocarbon Energy Company, which Shenhua Group has adopted, also falls under this process. 3. There is also a new process derived from the direct liquefaction method – the kerosene co-processing method. The kerosene co-processing method involves the hydrocracking of coal together with residue oil; the synergistic effect between coal and residue oil increases the oil yield and reduces investment costs. Since the 1970s, experts and scholars have been conducting research on synthetic oil. More recently, improvements have been made to the process of co-processing kerosene through numerous experiments and analyses; the step of \"hydrogenation\" during the reaction phase has been eliminated. This has reduced the reaction conditions, as well as production costs and capital investment, thereby making the industrial production of oil from coal a reality. Furthermore, by comprehensively developing coal-to-oil technology based on the structural characteristics of coal itself, in addition to producing fuel oil and high-quality asphalt, chemical products with high added value can also be manufactured. Based on the analysis of data from pilot tests and preliminary pilot-scale trials, 1 ton of oil can be produced from every 3.5 tons of coal. Building a plant with an annual production capacity of 1 million tons of liquid fuel (about 72% diesel and about 28% gasoline) requires only an investment of 2.5 billion RMB; this amount is one-third of the cost required for the direct liquefaction via hydrogenation method, and one-fifth of the cost for the indirect liquefaction method. The production cost per ton of oil is around 1,500 to 1,900 yuan (including all expenses such as raw materials, depreciation of fixed assets, and administrative costs). The selling price for gasoline and diesel at the factory is 2,500 yuan per ton, while the value of by-products such as asphalt, electrode coke, and phenol together is over 1,000 yuan. Thus, the total value per ton is 3,500 yuan. After deducting taxes and sales expenses, a profit of at least 1,000 yuan can be obtained per ton of diesel along with its by-products, resulting in an annual profit of 1 billion yuan.
I would like to ask whether hydrogen is actually necessary for the reaction
The direct liquefaction process requires hydrogenation in order to break down the organic structure of coal; together with solvent oil and catalysts that accelerate the reaction, it is then possible to produce distilled liquids.
The kerosene co-processing method described by the poster is quite remarkable: it eliminates the \"hydrogenation\" step in the reaction phase, **reducing the reaction conditions. Is it considered a solvent extraction method for coal? 1 ton of oil can be produced from every 3.5 tons of coal – how is hydrogen balanced?
Is it adding H'' from the residue oil to the coal? Does such a conversion rate decrease?
I am generally aware of what the original poster mentioned, and I am not interested in what this student referred to as “solvent extraction”. The process roughly goes like this: after the coal is turned into particles, it is mixed in certain proportions with anthracene oil or residue oil along with a small amount of catalyst. The mixture is then placed in an autoclave at atmospheric pressure (nitrogen is used to evacuate the air for safety reasons), and heated to 360–450 degrees. The temperature is maintained at this level for a certain period of time; the pressure isn’t very high, probably a few MPa (much lower than the pressure used in Shenhua’s direct liquefaction process). Then, the temperature is reduced and pressure is released, followed by discharge and separation. Through this series of operations, coal and anthracene oil (residue) can be cracked to produce oils such as kerosene and high-quality asphalt, while also generating a certain amount of hydrogen sulfide and ammonia as by-products. Through a simple analysis, I believe the effect of solvent extraction is not significant. The entire process is presumed to involve hydrogen in anthracene oil (residue) breaking down the complex molecular structure of coal, causing the coal to pyrolyze into asphalt and oils (the vitrinite component is highly inert and does not undergo significant changes), while the hydrogen itself further undergoes pyrolysis. The by-product hydrogen sulfide and ammonia are the results of hydrogen reacting with coal. It can be said that this process is somewhat feasible, but the hydrogen concentration in the reaction will not be high, resulting in a shallow degree of coal pyrolysis; only about 30% of the coal may be converted into asphalt, and even less will turn into oil products. The remaining 70% of the coal fails to undergo any reaction. The majority of the kerosene produced through co-processing is likely to be a product of the cracking of anthracene oil or residue oil. There is a problem here: oils can be separated through distillation, but separating asphalt from unreacted coal is a significant challenge! As for the cost-effectiveness mentioned by the original poster, I haven’t conducted any analysis, so I don’t dare to give an opinion in front of experts.
Was this technology developed by a company in Shenzhen? I seem to have heard something about it
This student’s explanation still didn’t help me understand: \"This results in a shallow degree of coal pyrolysis; only about 30% of the coal may be converted into asphalt.\" How can coal be converted into asphalt? Coal dry distillation yields coal tar, and the heavy fractions obtained from the distillation of coal tar are asphalt. 2. Does the hydrogen in anthracene oil (residue oil) break down the complex molecular structure of coal? Heat to 360-450 and maintain that temperature for a while; the pressure won’t be very high, perhaps a few MPa. Is the hydrogen in anthracene oil (residue) reactive? My fundamental understanding of the technology developed by a company in Shenzhen is that it involves low-temperature carbonization of coal: coal is heated along with anthracene oil or residue oil, along with a small amount of catalyst, to temperatures between 360 and 450 degrees. As a result, the coal partially decomposes to produce gas, tar, crude benzene, and semi-coke; the gaseous products cause the pressure in the system to rise. The partially pyrolyzed products of anthracene oil or residue oil, along with the light fractions of coal tar, become what is known as kerosene; high-quality asphalt, as well as unreacted coal and semi-coke, are then subjected to further processing. This method is very uneconomical, but “a company in Shenzhen” is likely not really interested in developing this technology; what matters to them is coal resources.
Zhuhai Sanjin High-Tech Industry Co., Ltd. is an enterprise under the China International Outlook Group (founded by Wang Daohan, Qian Weichang, and others), dedicated to integrated high-tech development and investment. In May 2005, in order to professionally develop, manufacture, and promote coal-to-oil technology and related products, the company jointly established Zhuhai Sanjin Coal-to-Oil Technology Co., Ltd. with Mr. Fang Keng (a member of the National Committee of the Chinese People’s Political Consultative Conference and former head of the **Productivity Promotion Bureau). The chairman of the company is Mr. Wu Ke, and the vice-chairman is Mr. Fang Keng. The company has always invested in and developed projects with a keen eye for opportunity. The projects it has developed and invested in include: (1) Rotary-type automotive air-conditioning compressors. This project was officially put into operation in Nanjing on December 28, 2001, with a registered capital of 120 million RMB. In 2003, it achieved annual sales of 100,000 units, and has since become one of the world’s top five manufacturers of rotary-type automotive air-conditioning compressors. (II) Production of diesel via direct coal liquefaction Through more than twenty years of research, the company’s scientific researchers have invented a \"process for producing liquid fuels from coal using thermal catalysis\" (commonly known as the \"hydrogen-free kerosene co-processing method\"). This invention has been patented and included by the Ministry of Science and Technology in the \"Key Promotion Plan for Scientific and Technological Achievements\" (project number 2003EC00304, certificate number 030368). (For details, please see the project description.) ) When people talk about a company in Shenzhen being very successful, they are probably referring to this one. I almost went there at graduation; that’s all I know.
This post was last edited by Clouds obscure the vision on 2009-8-18 at 10:48. It’s a bit amazing. I don’t know anything about hydrogenation-free technologies, but I do know that to turn coal into smaller molecules, hydrogenation is necessary – this is basic chemistry knowledge from middle school. The so-called hydrocarbon-free coal liquefaction should refer to the absence of hydrogen gas, not the absence of hydrogen altogether; otherwise, the chemical equations would need to be revised. What is this anthracene oil? A very good liquid solvent that acts as a hydrogen donor is tetralin, which consists of two benzene rings connected together, one of which is saturated and the other unsaturated. Without hydrogen, tetralin is able to supply hydrogen atoms to coal, facilitating its direct liquefaction and producing viscous aromatics and medium oil fractions at room temperature. The problem is that this so-called hydrogen donor must be unstable under the reaction conditions; tetralin itself undergoes dehydrogenation to form naphthalene. The key to the problem is where there are so many sources of hydrogen.
1# ryn: “It eliminates the ‘hydrogenation’ step in the reaction process, **reduces the reaction conditions, lowers production costs and capital investment, thus making the industrialization of coal-to-oil production possible**. Please provide authoritative evidence, OP.”