Method for liquifying coal mildly

Abstract

The invention relates to a method for liquifying coal mildly. The method mainly comprises steps of dry smashing coal samples and mixing with catalyst and hydrogen-donor solvent to form thick liquid; heating and then injecting into a reactor I, carrying out catalytic hydrogenation reaction on coal and hydrogen-donor solvent under mild condition, continuously dissolving out soluble components in products and coal; then injecting into a reactor II, flash distilling part of the product and solvent, rising temperature so as to split and coke left products to generate low boiling point compound and coke, wherein the coke can be used for preparing activated carbon and hydrogen. After the product which is vacuum flashed and purged through steam stripping is separated, different components are obtained, the component below 200 DEG C is condensed so as to obtain light oil, non-condensed gas and water, 200-300 DEG C component is condensed so as to obtain middle oil, after hydrotreating, the middle oil can be used as hydrogen-donor solvent, 300-500 DEG C component is condensed so as to obtain heavy oil which can be used for preparing chemicals or advanced carbon materials, and the component above 500 DEG C is condensed so as to obtain residual oil which can be used for preparing advanced carbon materials. The method has mild reaction conditions, the reactor is coupling, the efficient of the equipment is high, the yield of liquid product is high, the investment of the equipment is low, and the energy conversion efficiency is high.

Description

technical field [0001] The invention relates to a process method of coal temperature liquefaction, belongs to the field of clean energy technology and coal chemical industry, and refers to the production of hydrocarbon fuels and chemicals with coal. Background technique [0002] Coal liquefaction is a technology for producing gasoline, diesel, aviation kerosene and other chemicals from coal, which can be generally divided into two categories: direct liquefaction and indirect liquefaction. Developing coal conversion technology with high technological content, good economic benefits, and environmental friendliness, and transforming coal processing into clean and efficient secondary energy such as liquid fuel and gas fuel, is based on domestic energy advantages, ensuring sustainable energy development, and strengthening energy strategies An important way of safety. [0003] Coal liquefaction yields products in various forms, such as ash-free coal, fuel oil, synthetic crude oil...

AI Technical Summary

Problems solved by technology

At present, there are some representative coal liquefaction technologies, such as: 1) Fischer-Tropsch synthesis, which generates synthesis gas (carbon monoxide and hydrogen) from coal gasification, and then uses the synthesis gas as raw material to synthesize liquid fuels and chemical products, but its process has some limitations. Disadvantages, such as high hydrogen demand, high cost, low relative output, and low thermal efficiency; 2) Coal is directly liquefied, and coal undergoes hydrogenation reaction under certain conditions, and the product is separated to obtain oil, gas, water and solid residue. The oil product is then hydrogenated to obtain liquid fuel. The main technical core is the high-pressure hydrogenation and dissolution process of coal, which has disadvantages such as difficulty in catalyst separation, easy blockage of coal slurry heat exchanger, and difficulty in high-temperature and high-pressure solid-liquid separation.

Chinese patents CN1438294A and CN101987962A introduce two coal liquefaction processes, each of which has different process characteristics, but both have disadvantages such as high pressure, high hydrogen consumption, and narrow raw material adaptability, resulting in low economic efficiency and poor practicability

In addition, direct combustion or gasification of volatile matter in coal fails to realize cascade utilization of resources, which not only causes waste of coal resources, but also causes environmental pollution

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