Product processing of coal-to-oil
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This post was last edited by jordan569 on 2013-1-6 at 20:37. How should the products obtained from coal-to-oil processing be treated? Should they be fractionated first, just like in the petrochemical industry, and then refined through hydrogenation? . Note # ) # # , .
It’s similar to oil processing; it follows the same process, only with different parameters.
The main function of coal-to-oil conversion is to transform solid coal into liquid crude oil; at this point, the primary task is completed. The further processing of this liquefied crude oil is similar to the quality-improving processes used in the petrochemical industry. However, due to certain differences between liquefied oils and petroleum products, it is necessary to develop catalysts specific for liquefied oils. Overall, the catalysts required are still precious metals such as molybdenum and cobalt. The current post-processing method in the coal direct liquefaction demonstration plant is as follows: the crude oil obtained from coal liquefaction undergoes hydrogenation stabilization to remove some sulfur and nitrogen, as well as partial aromatics hydrogenation. Through a distillation unit, this oil is separated into light oil (〈220°C), medium oil (220–350°C), and heavy oil (〉350°C). The heavy oil is returned to the coal slurry preparation unit as a circulating solvent, while the light oil and medium oil are mixed together and sent to the hydroprocessing unit, where qualified products such as gasoline and diesel are produced.
Are the oils produced from coal-to-oil processes, after undergoing hydrogenation, distillation, and hydrorefining, of higher quality than those produced through petrochemical methods?
The product structure is different too! In products that are directly liquefied, the levels of aromatics and cyclohydrocarbons are relatively high. Suitable for diesel......
Due to the C/H ratio and the characteristics of the aromatic nucleus structure, the processes involved in converting coal resources into oil differ from those used in traditional oil refining. By protecting free radicals and extracting distillate oils and asphaltenes, they can serve as raw materials for oil refining as well as an ideal source for chemical industry raw materials. Choose the subsequent processing method based on different purposes.
This post was last edited by *ao*ang010 on 2009-6-14 at 21:33. The heavy oils, heavy waxes, and light oils produced from coal-based oil products through indirect liquefaction require pre-hydrogenation refining, hydrogenation refining, and distillation, in order to ultimately obtain the main product of coal-based oil processing – diesel. The oil produced from coal-to-oil processes has a better quality than that produced from petroleum refining.
The oil produced from coal-to-oil conversion has a different composition and structure from crude oil. It first undergoes hydrorefining to remove sulfur, nitrogen, oxygen, and certain metal ions; after that, hydrogen is separated at different temperature levels before distillation takes place. The heavier components are used as recycled oil for hydrocracking. The process is similar to that in conventional refineries, but this method primarily yields diesel, and the quality of this diesel is better than that produced in refineries. It represents one effective way to produce clean diesel
Why is it said that the oil produced from coal-to-oil conversion has a better quality than that from refineries? Please give an example
The concept of coal-to-oil is too broad; this question cannot be answered. The appropriate handling methods can only be determined by analyzing specific products, although the individual chemical processes involved are similar to those in petroleum refining
The crude oil obtained from coal liquefaction is subjected to hydrogenation stabilization to remove some of the sulfur and nitrogen, as well as to carry out partial aromatization hydrogenation. Through a distillation unit, it is divided into light oil (〈220°C), medium oil (220–350°C), and heavy oil (〉350°C). The heavy oil is returned to the coal slurry preparation unit as a circulating solvent, while the light oil and medium oil are mixed together and sent to the hydroprocessing unit, where qualified products such as gasoline and diesel are produced through separation. Additional note: Another portion of light oil (crude naphtha) is used as an absorbent to absorb the naphtha and liquefied gas components in the off-gases from various distillation towers, similar to a catalytic absorption stabilization unit. Some heavy oil and medium oil are also used as flushing oil to clean valves and instruments in solids-containing equipment, or to reduce temperature and prevent coking.