CN105400548A - Coal hydrogasification method and system - Google Patents

Abstract

The invention discloses a coal hydrogasification method and system, relates to the technical field of coal gasification, and aims to improve the carbon conversion efficiency of the coal hydrogasification system. The coal hydrogasification method comprises the following processes: coal hydrogasification process: raw coal powder and hydrogen-containing reaction gas are subjected to coal hydrogasification reaction in a coal hydrogasification unit to obtain semicoke; semicoke coal water slurry preparation process: the semicoke obtained in the coal hydrogasification process is utilized to prepare semicoke coal water slurry in the semicoke coal water slurry preparation unit; semicoke coal water slurry gasification process: semicoke coal water slurry is subjected to coal water slurry gasification reaction in the semicoke coal water slurry gasification unit to obtain semicoke gasified raw gas, the semicoke gasified raw gas is subjected to after-treatment to obtain hydrogen-containing product gas, and the hydrogen-containing product gas is fed into the coal hydrogasification unit to participate in the coal hydrogasification reaction.

Description

Coal hydrogenation gasification method and system

technical field

The invention relates to the technical field of coal gasification, in particular to a coal hydrogenation gasification method and system.

Background technique

Coal hydrogasification is a kind of coal gasification, which refers to the reaction of raw coal powder and hydrogen-containing reaction gas under high temperature and high pressure conditions (800 ° C ~ 1000 ° C, 3 MPa ~ 8 MPa) to generate methane-rich gas and light oil products. process. Compared with traditional coal gasification, coal hydrogenation gasification has the characteristics of simple process, high thermal efficiency and low pollution, so it has been widely concerned and applied. However, in the process of coal hydrogasification, a large amount of semi-coke is usually produced, and the output of semi-coke accounts for about 50% of the feed, and the carbon content of semi-coke is equivalent to that of raw coal powder, which has high utilization value , therefore, how to effectively utilize this part of the coke has become an important factor limiting the efficiency of the coal hydrogasification system.

In the prior art, the semi-coke is usually discharged directly, so the carbon source in the semi-coke has not been effectively utilized, resulting in low carbon conversion efficiency in the coal hydrogasification system.

Contents of the invention

The purpose of the present invention is to provide a coal hydrogasification method and system, which is used to solve the technical problem of low carbon conversion efficiency of the coal hydrogasification system due to the ineffective use of the carbon source of semi-coke.

In order to achieve the above object, the present invention provides the following technical solutions:

In one aspect, the present invention provides a coal hydrogasification method, comprising:

Coal hydrogasification process, raw coal powder and hydrogen-containing reaction gas undergo coal hydrogasification reaction in the coal hydrogasification unit to obtain semi-coke;

Semi-coke coal-water slurry preparation process, the semi-coke coal-water slurry preparation unit uses the semi-coke obtained in the coal hydrogenation gasification process to prepare semi-coke coal-water slurry;

Semi-coke coal-water slurry gasification process, semi-coke coal-water slurry gasification reaction in the semi-coke coal-water slurry gasification unit to obtain semi-coke gasification crude gas, semi-coke gasification crude gas is obtained after post-processing Hydrogen-containing product gas, the hydrogen-containing product gas is passed into the coal hydrogenation gasification unit to participate in the coal hydrogenation gasification reaction.

In another aspect, the present invention provides a coal hydrogenation gasification system, including a coal hydrogenation gasification unit, a semi-coke coal-water slurry preparation unit, and a semi-coke coal-water slurry gasification unit; wherein,

The coal hydrogasification unit is used to make raw coal powder and hydrogen-containing reaction gas undergo coal hydrogasification reaction to obtain semi-coke;

The semi-coke coal-water slurry preparation unit is communicated with the coal hydrogenation gasification unit, and the semi-coke coal-water slurry preparation unit uses the semi-coke output from the coal hydrogenation gasification unit to prepare semi-coke coal-water slurry;

The semi-coke coal-water slurry gasification unit is respectively connected with the semi-coke coal-water slurry preparation unit and the coal hydrogenation gasification unit, and is used to make the semi-coke coal-water slurry output by the semi-coke coal-water slurry preparation unit Coal-water slurry gasification reaction is carried out to obtain semi-coke gasification crude gas, and the semi-coke gasification crude gas is post-processed to obtain hydrogen-containing product gas, which is passed into the coal hydrogenation gasification unit to participate in coal processing Hydrogenation reaction.

In the coal hydrogenation gasification method provided by the present invention, in the semi-coke coal-water slurry preparation process, the semi-coke obtained in the coal hydrogenation gasification process is made into semi-coke coal-water slurry by the semi-coke coal-water slurry preparation unit, In the semi-coke coal-water slurry gasification process, the semi-coke coal-water slurry produced in the semi-coke coal-water slurry preparation process undergoes a coal-water slurry gasification reaction through the semi-coke coal-water slurry gasification unit to obtain semi-coke gasification Crude gas, and post-processing the semi-coke gasification crude gas to obtain hydrogen-containing product gas, which is passed into the coal hydrogenation gasification unit and used as raw material gas for hydrogen-containing reaction gas. Therefore, the coal hydrogasification method provided by the present invention utilizes the semi-coke with a relatively high carbon content obtained in the coal hydrogasification process to generate hydrogen-containing product gas, which provides for the coal hydrogasification reaction in the coal hydrogasification process. Compared with the direct discharge of semi-coke in the prior art, the raw material gas effectively utilizes the carbon source in the semi-coke, thereby improving the carbon conversion efficiency in the coal hydrogasification system.

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present invention, and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention, and do not constitute improper limitations to the present invention. In the attached picture:

Fig. 1 is the schematic flow chart of the coal hydrogasification method provided by the embodiment of the present invention;

Fig. 2 is the schematic flow sheet of a kind of semi-coke coal water slurry preparation technology that the embodiment of the present invention provides;

Fig. 3 is the schematic flow sheet of another kind of semi-coke coal-water slurry preparation technology that the embodiment of the present invention provides;

Fig. 4 is the schematic flow sheet of semi-coke coal-water slurry gasification process that the embodiment of the present invention provides;

Fig. 5 is a schematic flow chart of the coal hydrogasification process provided by the embodiment of the present invention;

Fig. 6 is a schematic structural diagram of a coal hydrogasification system provided by an embodiment of the present invention;

Fig. 7 is a schematic structural diagram of another coal hydrogasification system provided by an embodiment of the present invention;

Figure 8 is a schematic structural view of a semi-coke coal-water slurry preparation unit provided by an embodiment of the present invention;

Fig. 9 is a schematic structural diagram of another semi-coke coal-water slurry preparation unit provided by an embodiment of the present invention.

Reference signs:

10-coal hydrogenation gasification unit, 20-semi-coke coal water slurry preparation unit,

30-semi-coke coal-water slurry gasification unit, 11-coal hydrogenation gasifier,

12-dust removal device, 13-heat exchange device,

14-oil extraction device, 15-hydrogen separation device,

16-semi-coke cooling and pressure-reducing device, 21-semi-coke grinding device,

22- pulverized coal grinding device, 23- wet grinding device,

24-mixing pulping device, 25-drying device,

26-crushing device, 27-vibrating screen,

31-coal water slurry gasifier, 32-carbon monoxide conversion device,

33 - Product gas cleaning device.

detailed description

In order to further illustrate the coal hydrogasification system and method provided by the embodiments of the present invention, a detailed description will be given below in conjunction with the accompanying drawings.

Please refer to Fig. 1, an embodiment of the present invention provides a coal hydrogasification method, including:

Step 100, coal hydrogenation gasification process, the raw coal powder and hydrogen-containing reaction gas are subjected to coal hydrogenation gasification reaction in the coal hydrogenation gasification unit to obtain semi-coke;

Step 200, semi-coke coal-water slurry preparation process, the semi-coke coal-water slurry preparation unit uses the semi-coke obtained in the coal hydrogenation gasification process to prepare semi-coke coal-water slurry;

Step 300, the semi-coke coal-water slurry gasification process, the semi-coke coal-water slurry gasification reaction is carried out in the semi-coke coal-water slurry gasification unit, and the semi-coke gasification crude gas is obtained, and the semi-coke gasification crude gas is passed through The hydrogen-containing product gas is obtained after post-processing, and the hydrogen-containing product gas is passed into the coal hydrogasification unit to participate in the coal hydrogenation gasification reaction.

In the coal hydrogasification method provided in the embodiment of the present invention, in the semi-coke coal-water slurry preparation process, the semi-coke obtained in the coal hydrogasification process is made into semi-coke coal-water slurry by the semi-coke coal-water slurry preparation unit , in the semi-coke coal-water slurry gasification process, the semi-coke coal-water slurry produced in the semi-coke coal-water slurry preparation process undergoes a coal-water slurry gasification reaction through the semi-coke coal-water slurry gasification unit to obtain semi-coke The crude gas is gasified, and the semi-coke gasified crude gas is post-treated to obtain a hydrogen-containing product gas, which is passed into a coal hydrogenation gasification unit and used as a raw material gas for a hydrogen-containing reaction gas. Therefore, the coal hydrogasification method provided in the embodiment of the present invention utilizes the semi-coke with a relatively high carbon content obtained in the coal hydrogasification process to generate hydrogen-containing product gas, which is the coal hydrogasification process in the coal hydrogasification process. The reaction provides the raw material gas, and compared with the direct discharge of the semi-coke in the prior art, the carbon source in the semi-coke is effectively used, thereby improving the carbon conversion efficiency in the coal hydrogasification system.

In addition, the coal hydrogenation gasification method provided by the embodiment of the present invention is used in conjunction with the coal hydrogenation gasification unit, the semi-coke coal-water slurry preparation unit and the semi-coke coal-water slurry gasification unit. The semi-coke with high carbon content generates hydrogen-containing product gas, which provides raw material gas for the coal hydrogasification reaction in the coal hydrogasification unit, realizes the hydrogen supply and demand balance of the coal hydrogasification system, and reduces the impact on the coal hydrogasification system. The demand for external hydrogen is reduced, thereby saving costs.

Furthermore, the coal hydrogenation gasification method provided by the embodiment of the present invention is used in conjunction with the coal hydrogenation gasification unit, the semi-coke coal-water slurry preparation unit and the semi-coke coal-water slurry gasification unit, and the coal hydrogenation gasification reaction is used. The semi-coke with a higher carbon content generates hydrogen-containing product gas, which provides raw material gas for the coal hydrogasification reaction in the coal hydrogasification unit. Compared with the direct combustion of semi-coke in the prior art, energy waste is reduced, and Environmental pollution is reduced.

In the above examples, after the completion of the coal hydrogasification process, the obtained semi-coke is a porous particle with relatively weak hydrophilicity, so the concentration of the semi-coke coal-water slurry prepared using only semi-coke is relatively low (40% or so), therefore, in order to increase the slurry concentration of the semi-coke coal-water slurry, the semi-coke can be ground to obtain semi-coke powder, and the pulping coal powder made from raw coal will be added to the semi-coke coal-water slurry, through Particle size grading is carried out on semi-coke powder and pulping coal powder to increase the slurry concentration of semi-coke coal-water slurry. The semi-coke coal-water slurry preparation process can adopt the following two methods:

Mode 1, please refer to Figure 2. The semi-coke coal-water slurry includes semi-coke powder and pulping coal powder. The semi-coke coal-water slurry preparation unit includes a semi-coke grinding device and a coal powder grinding device. The semi-coke coal-water slurry preparation process includes:

Step 210, the grinding step, using the semi-coke grinding device to grind the semi-coke obtained in the coal hydrogasification process to form semi-coke powder, and using the coal powder grinding device to grind the raw coal to form pulped coal powder, pulped coal The average particle size of the powder is greater than the average particle size of the semi-coke powder;

Step 220, the step of preparing semi-coke coal-water slurry, uniformly mixing semi-coke powder, pulping coal powder and water to prepare semi-coke coal-water slurry.

During specific implementation, in the grinding step, the semi-coke obtained in the coal hydrogasification process can also be cooled before the semi-coke obtained in the coal hydrogasification process is ground to form semi-coke powder by the semi-coke grinding device Reduce the pressure to facilitate the use of the semi-coke grinding device to grind the semi-coke; before the raw coal is ground by the coal powder grinding device to form pulped coal powder, the raw coal can be dried in the drying device first, and after drying The moisture content of the final raw coal is less than or equal to 8%, and the raw coal dried by the drying device is placed in a crushing device, and is crushed into raw coal particles with a particle size of 10 mm or less in the crushing device. The raw coal particles are placed in the coal powder grinding device, and the initial coal powder is ground in the coal powder grinding device, and then the initial coal powder is passed through the vibrating screen to obtain pulping coal powder that meets the requirements, and the coarse coal powder that does not meet the requirements is returned to the Continue grinding in the pulverized coal grinding device.

In the semi-coke coal-water slurry preparation process, semi-coke powder, pulping coal powder and water can be placed in a mixing pulping device according to a certain ratio, and the semi-coke powder, pulping coal powder and water are stirred evenly to make Get semi-coke coal water slurry.

In the semi-coke coal-water slurry preparation process, the semi-coke is firstly ground into semi-coke powder, and the coal is ground into pulped coal powder, and the average particle size of the semi-coke powder is smaller than that of the pulped coal powder, and the average The semi-coke powder with smaller particle size is mixed with the pulped coal powder with larger particle size, and the semi-coke powder with smaller average particle size is filled in the gaps of the pulped coal powder with larger average particle size through particle size gradation. Therefore, the slurry concentration of the semi-coke coal-water slurry is increased, and the stability and fluidity of the semi-coke coal-water slurry are improved.

It is worth mentioning that semi-coke with porous particles is mainly formed due to the rapid expansion of raw coal powder in the process of coal hydrogasification reaction, so semi-coke is easier to grind, while raw coal is more difficult to grind than semi-coke. Therefore, according to the grindability of semi-coke and raw coal, semi-coke and raw coal are ground separately, semi-coke is ground into semi-coke powder with a smaller average particle size, and raw coal is ground into pulped coal with a larger average particle size Powder can effectively reduce the energy consumption when grinding semi-coke and raw coal separately, and save the time when grinding semi-coke and raw coal separately.

The semi-coke coal-water slurry preparation process provided by mode 1 adopts dry pulping, and the semi-coke coal-water slurry preparation process can also adopt dry-wet pulping.

Mode 2, please refer to Figure 3. The semi-coke coal-water slurry includes semi-coke powder and pulping coal powder. The semi-coke coal-water slurry preparation unit includes a semi-coke grinding device and a wet grinding device. The semi-coke coal-water slurry preparation process includes:

Step 210', semi-coke grinding step, using a semi-coke grinding device to grind the semi-coke obtained in the coal hydrogasification process to form semi-coke powder;

Step 220', semi-coke water slurry preparation step, mixing semi-coke powder with water and stirring evenly to prepare semi-coke water slurry;

Step 230', semi-coke coal-water slurry preparation step, using a wet grinding device to grind the semi-coke water slurry, raw coal and water to form a semi-coke coal-water slurry.

During the specific implementation, in the preparation step of the semi-coke coal-water slurry, before the semi-coke water slurry, raw coal and water are simultaneously ground by the wet grinding device, the raw coal can be placed in the crushing device, and the raw coal can be crushed into granular particles in the crushing device. Raw coal particles with a diameter less than or equal to 10mm, raw coal particles, semi-coke water slurry and water are placed in a wet grinding device at the same time, and the semi-coke water composed of semi-coke powder, pulping coal powder and water is formed by grinding in the wet grinding device coal slurry. In mode 2, when raw coal is ground, wet grinding is used, which saves energy compared with the way of grinding raw coal in mode 1 using dry grinding.

In order to further increase the slurry concentration of the semi-coke coal-water slurry, preferably, in the semi-coke coal-water slurry, the mass ratio of semi-coke powder to pulping coal powder is 1:9 to 1:1; the semi-coke coal-water slurry includes water , the mass percentage of water in the semi-coke coal-water slurry is 30% to 40%. For example, please refer to Table 1, when the mass ratio of semi-coke powder and pulping coal powder is selected as 1:9, after measurement, the slurry concentration of the prepared semi-coke coal-water slurry is 65%; When the mass ratio of semi-coke powder and pulping coal powder is selected as 3:7, after measurement, the slurry concentration of the prepared semi-coke coal water slurry is 62%; when the mass ratio of semi-coke powder and pulping coal powder is selected as 1 : 1, through measurement, the slurry concentration of the prepared semi-coke coal-water slurry is 60%. In summary, when the mass ratio of semi-coke powder and pulping coal powder is selected as 1:9 to 1:1, the slurry concentration of the prepared semi-coke coal-water slurry is greater than or equal to 60%, which meets the requirements of semi-coke coal-water slurry. The slurry is transported to the semi-coke coal-water slurry gasification unit, and meets the feed requirements of the semi-coke coal-water slurry gasification unit.

Table 1

In the semi-coke coal-water slurry, water accounts for 30% to 40% of the mass percentage of the semi-coke coal-water slurry, which can meet the requirements for producing semi-coke coal-water slurry, ensure a high concentration of semi-coke coal-water slurry, and make the semi-coke coal-water slurry Semi-coke coal water slurry has good fluidity and stability.

In the embodiment of the present invention, in the semi-coke coal-water slurry, the average particle size of the semi-coke powder is 10 μm-50 μm; the average particle size of the pulping coal powder is 200 μm-350 μm. In the first method, the semi-coke grinding device is used to grind the semi-coke into semi-coke powder with an average particle size of 10 μm to 50 μm, which can prevent the semi-coke powder from being produced due to the strong hydrophobicity of the semi-coke powder when the average particle size is greater than 50 μm. The difficulty of pulping increases, and at the same time, it can prevent the prolongation of the grinding time of semi-coke due to the average particle size of semi-coke powder being less than 10 μm; the raw coal is ground into slurry-making coal powder with an average particle size of 200 μm to 350 μm through a coal powder grinding device. The gradation effect of the pulped coal powder in the particle size range and the semi-coke powder with an average particle size of 10 μm to 50 μm is better, and the pulped coal powder in this particle size range and the semi-coke powder with an average particle size of 10 μm to 50 μm The mixed semi-coke coal-water slurry has good fluidity and stability.

It is worth mentioning that when the semi-coke coal-water slurry is prepared in the second way, since the semi-coke has been ground by the semi-coke grinding device and the wet grinding device successively, the semi-coke obtained by grinding the semi-coke by the semi-coke grinding device The average particle size of the coke powder may be greater than 50 μm.

When using method 1 to prepare semi-coke coal-water slurry, the average particle size of semi-coke powder is 10 μm to 50 μm; the average particle size of pulping coal powder is 200 μm to 350 μm. Compared with pulping coal powder, semi-coke powder It is a kind of superfine powder, and when the raw coal is ground by a coal powder grinding device, a part of the superfine powder with a particle size equivalent to the average particle size of the semi-coke powder will also be obtained. In order to prevent the prepared semi-coke coal-water slurry from Containing too much ultra-fine powder leads to a reduction in the slurry concentration, fluidity and stability of the semi-coke coal-water slurry. Preferably, the raw coal is ground by a coal powder grinding device to obtain the initial coal powder, and the initial coal powder passes through twice Vibrating sieve, when passing through the vibrating sieve for the first time, the coarse coal powder with a particle size larger than the maximum particle size of pulping coal powder (for example, 1000 μm) is screened out; Ultrafine powder with a similar average particle size (for example, particle size less than or equal to 45 μm) is screened out. When preparing semi-coke coal-water slurry, semi-coke powder and pulping coal powder with a particle size equivalent to the average particle size of semi-coke powder form superfine powder, and the mass percentage of superfine powder in the solid raw material of semi-coke coal-water slurry should be 50%, that is, the superfine powder accounts for 50% of the mass sum of the semi-coke powder and pulping coal powder, so as to prevent the semi-coke coal-water slurry from containing too much ultra-fine powder and cause the slurry concentration of the semi-coke coal-water slurry, Both fluidity and stability are reduced.

It is worth pointing out that the maximum particle size of pulped coal powder is preferably less than or equal to 1000 μm, in order to prevent the reaction rate and chemical Conversion rates.

In order to improve the stability and fluidity of the semi-coke coal-water slurry, in the embodiment of the present invention, the semi-coke coal-water slurry further includes additives, and the additive accounts for 0.2%-2% by mass of the semi-coke coal-water slurry. During specific implementation, when adopting mode one to prepare semi-coke coal-water slurry, the additive can be placed in the mixing pulping device together with semi-coke powder, pulping coal powder and water, and the semi-coke coal-water slurry can be formed after mixing evenly, or can be After mixing the semi-coke powder, pulping coal powder and water evenly, place them in the mixing pulping device, and mix them uniformly to form semi-coke coal-water slurry; when adopting the second method to prepare semi-coke coal-water slurry, the additive can The coke water slurry, raw coal and water are placed in the wet grinding device at the same time, and the additives, semi-coke powder, pulping coal powder and water are uniformly mixed through the wet grinding device to form a semi-coke coal-water slurry containing additives.

Add additives to the semi-coke coal-water slurry to prevent the semi-coke coal-water slurry from settling during transportation, and reduce the viscosity of the semi-coke coal-water slurry, thereby improving the stability and fluidity of the semi-coke coal-water slurry. Add 0.2% to 2% additives to the semi-coke coal-water slurry to prevent the increase in the preparation cost of the semi-coke coal-water slurry due to too many additives, and at the same time prevent the stability of the semi-coke coal-water slurry caused by too little additive Improvements in sex and mobility are less effective.

In the above embodiments, the additives can be of various types, for example, lignosulfonic acid-based additives, naphthalenesulfonic acid-based additives, sulfamic acid-based additives, etc., and can also be mixed additives formed by compounding various additives. In the embodiment of the present invention, the additive is a naphthalenesulfonic acid additive.

Please refer to Figure 4. The semi-coke coal-water slurry gasification unit includes a coal-water slurry gasification furnace and a post-processing device. The semi-coke coal-water slurry gasification process includes:

Step 310, semi-coke coal-water slurry gasification step, the semi-coke coal-water slurry and oxygen-containing gas are placed in the coal-water slurry gasification furnace, so that the semi-coke coal-water slurry generates coal-water slurry gas in the coal-water slurry gasification furnace gasification reaction to obtain semi-coke gasification crude gas;

Step 320, crude gas post-processing step, passing the semi-coke gasification crude gas into the post-processing device, the post-processing device performs post-processing on the semi-coke gasification crude gas to obtain hydrogen-containing product gas, and the hydrogen-containing product gas is passed into the coal Participate in the coal hydrogasification reaction in the hydrogasification unit.

During specific implementation, in the semi-coke coal-water slurry gasification step, after the semi-coke coal-water slurry and oxygen-containing gas undergo coal-water slurry gasification reaction in the coal-water slurry gasifier, the obtained semi-coke gasification crude gas is mainly Including carbon monoxide and hydrogen; the post-processing device includes a carbon monoxide conversion device and a product gas purification device. The carbon monoxide shift reaction occurs in the semi-coke gasification crude gas, so that the carbon monoxide in the semi-coke gasification crude gas undergoes a carbon monoxide shift reaction to generate hydrogen, and the semi-coke gasification crude gas after the carbon monoxide shift reaction in the carbon monoxide shift device is passed into the product gas purification device, and the product gas The purification device removes a small amount of carbon monoxide, a small amount of sulfur dioxide and other gases that are not conducive to the coal hydrogasification reaction in the semi-coke gasification crude gas after the carbon monoxide shift reaction occurs in the carbon monoxide shift device, and forms a hydrogen-containing product gas mainly composed of hydrogen.

Please refer to Fig. 5, in the embodiment of the present invention, the coal hydrogasification unit includes a coal hydrogasification furnace, a semi-coke cooling and depressurization device, and a gas purification and separation device, wherein the coal hydrogasification furnace is provided with a chilling device, The coal hydrogasification process includes:

Step 110, raw coal powder and hydrogen-containing reaction gas are subjected to coal hydrogenation gasification reaction in a coal hydrogenation gasifier to obtain semi-coke and coal hydrogenation gasification crude gas;

Step 120, cooling and depressurizing the semi-coke obtained from the coal hydrogasification reaction through the semi-coke cooling and depressurizing device, and passing the semi-coke after cooling and depressurization to the semi-coke coal-water slurry preparation unit;

Step 130: Coal hydrogasification crude gas is cooled by the gas quenching device and then passed into the gas purification and separation device, and the coal hydrogenation gasification crude gas chilled by the gas quenching device is purified and separated by the gas purification and separation device to obtain The hydrogen-containing residual gas is passed into the coal hydrogenation gasification furnace to participate in the coal hydrogenation gasification reaction.

In the above example, the semi-coke obtained from the coal hydrogasification reaction is cooled and depressurized in the semi-coke cooling and pressure reducing device, and then passed into the semi-coke coal-water slurry preparation unit, which can prevent the semi-coke from being transported to the semi-coke water coal The temperature and pressure of the semi-coke in the slurry preparation unit are relatively high, which increases the difficulty of pulping, which is convenient for the pulping operation in the semi-coke coal-water slurry preparation unit.

The gas purification and separation device includes a dust removal device, a heat exchange device, an oil extraction device and a hydrogen separation device, and the crude gas outlet of the coal hydrogenation gasifier is sequentially connected to the dust removal device, the heat release side of the heat exchange device, the oil extraction device and the hydrogen gas The inlet of the heat-absorbing side of the separation device and the heat-exchanging device is connected with the hydrogen separation device and the semi-coke coal-water slurry gasification unit, and the outlet of the heat-absorbing side of the heat-exchanging device is connected with the coal hydrogenation gasifier. Raw coal powder and hydrogen-containing reaction gas are subjected to coal hydrogenation gasification reaction in coal hydrogenation gasifier, and coal hydrogenation gasification crude gas containing light oil products (such as benzene, toluene, naphthalene, etc.), methane and hydrogen, etc. is also obtained , the coal hydrogenation gasification crude gas obtained from the coal hydrogenation gasification reaction is quenched by the chilling device in the coal hydrogenation gasification furnace and then passed into the dust removal device, and the fine particle semi-coke entrained in the coal hydrogenation gasification crude gas is passed through the dust removal device Filtration; coal hydrogenation gasification crude gas after dust removal is passed into the heat release side of the heat exchange device, and performs heat exchange with the gas in the heat absorption side of the heat exchange device, and pre-heats the gas in the heat absorption side of the heat exchange device. Heat, so that the temperature of the gas discharged from the outlet of the heat-absorbing side of the heat exchange device reaches about 600°C, and the coal hydrogenation gasification crude gas after dust removal is cooled to form coal hydrogenation gasification crude gas with reduced temperature; the coal hydrogenation gasification crude gas with reduced temperature The hydrogenated crude gas is passed into the oil extraction device, and the light oil in the coal hydrogenated gasification gas with lower temperature is extracted through the oil extraction device; after the light oil is extracted, the coal hydrogenated gasified crude gas is passed through into the hydrogen separation device, through the hydrogen separation device to separate the gas that is not conducive to the coal hydrogenation gasification reaction in the coal hydrogenation gasification after the light oil product is extracted, and obtain the hydrogen-containing residual gas, which is passed into the exchange The heat-absorbing side of the heat device leads to the coal hydrogenation gasifier after heat exchange in the heat exchange device, and is used as the raw material gas of the hydrogen-containing reaction gas to participate in the coal hydrogenation gasification reaction, and the light oil is extracted through the hydrogen separation device After coal hydrogasification crude gas is processed, methane is also obtained. The gas in the heat-absorbing side of the heat exchange device includes hydrogen-containing product gas output from the semi-coke coal-water slurry gasification unit, hydrogen-containing residual gas output from the hydrogen gas separation device, and external hydrogen gas.

The coal hydrogenation gasification crude gas obtained from the coal hydrogasification reaction is quenched under the action of the chilling device in the coal hydrogasification furnace, which can prevent the light oil in the coal hydrogenation gasification crude gas from decomposing at high temperature; The chilled coal hydrogenation gasification crude gas is processed by the gas purification and separation device to obtain hydrogen-containing residual gas, and the hydrogen-containing residual gas is passed into the coal hydrogenation gasification furnace to participate in the coal hydrogenation gasification reaction, realizing the efficient recycling of hydrogen , reducing the demand for external hydrogen in the coal hydrogenation gasification system and saving costs.

Please refer to Fig. 6, an embodiment of the present invention also provides a coal hydrogasification system, including a coal hydrogasification unit 10, a semi-coke coal-water slurry preparation unit 20 and a semi-coke coal-water slurry gasification unit 30; wherein, the coal Hydrogenation gasification unit 10 is used to make raw coal powder and hydrogen-containing reaction gas undergo coal hydrogasification reaction to obtain semi-coke; The unit 20 utilizes the semi-coke output by the coal hydrogenation gasification unit 10 to produce a semi-coke coal-water slurry; the semi-coke coal-water slurry gasification unit 30 communicates with the semi-coke coal-water slurry preparation unit 20 and the coal hydrogenation gasification unit 10 respectively, Used to make the semi-coke coal-water slurry output from the semi-coke coal-water slurry preparation unit 20 undergo gasification reaction to obtain semi-coke gasification crude gas, and post-process the semi-coke gasification crude gas to obtain hydrogen-containing product gas , the hydrogen-containing product gas is passed into the coal hydrogasification unit 10 to participate in the coal hydrogasification reaction.

During specific implementation, please continue to refer to Fig. 6, the raw coal powder and the hydrogen-containing reaction gas are input into the coal hydrogasification unit 10, and the coal hydrogasification reaction occurs in the coal hydrogasification unit 10 to obtain a higher Semi-coke with high carbon content; the semi-coke obtained from the coal hydrogasification reaction is transported to the semi-coke coal-water slurry preparation unit 20, and under the action of the semi-coke coal-water slurry preparation unit 20, the semi-coke coal-water slurry is formed; the semi-coke The coal-water slurry is transported to the semi-coke coal-water slurry gasification unit 30, and the water-gas slurry gasification reaction occurs in the semi-coke coal-water slurry gasification unit 30, and the semi-coke gasification crude gas is obtained, and the semi-coke gasification crude gas The coal mainly contains carbon monoxide and hydrogen. After the semi-coke gasification crude coal gas is post-treated, the hydrogen-containing product gas is obtained. The hydrogen-containing product gas is transported to the coal hydrogenation gasification unit 10 and used as the raw material gas for the hydrogen-containing reaction gas. coal hydrogasification reaction.

As can be seen from the above, in the coal hydrogasification system provided by the embodiment of the present invention, the semi-coke output from the coal hydrogasification unit 10 is made into a semi-coke coal-water slurry through the semi-coke coal-water slurry preparation unit 20, and the semi-coke coal-water slurry is prepared by the semi-coke coal-water slurry The slurry gasification unit 30 makes the semi-coke coal-water slurry produced by the semi-coke coal-water slurry preparation unit 20 undergo a coal-water slurry gasification reaction to obtain the semi-coke gasification crude gas, and performs post-treatment on the semi-coke gasification crude gas , to obtain a hydrogen-containing product gas, which is passed into the coal hydrogasification unit 10 and used as a raw material gas for a hydrogen-containing reaction gas to participate in the coal hydrogasification reaction. Therefore, the coal hydrogenation gasification system provided by the embodiment of the present invention is obtained through coal hydrogenation gasification reaction through coal hydrogenation gasification unit 10, semi-coke coal-water slurry preparation unit 20 and semi-coke coal-water slurry gasification unit 30. The semi-coke with a relatively high carbon content generates hydrogen-containing product gas, which provides raw material gas for the coal hydrogasification reaction in the coal hydrogasification unit 10, which is comparable to the prior art in which the semi-coke is directly discharged from the coal hydrogasification system Ratio, the carbon source in the semi-coke is effectively utilized, thereby improving the carbon conversion efficiency in the coal hydrogasification system.

In addition, the coal hydrogenation gasification system provided by the embodiment of the present invention is obtained through the combined use of the coal hydrogenation gasification unit 10, the semi-coke coal-water slurry preparation unit 20 and the semi-coke coal-water slurry gasification unit 30, and utilizes coal hydrogenation gasification reaction to obtain The semi-coke with a relatively high carbon content generates hydrogen-containing product gas, which provides raw material gas for the coal hydrogasification reaction in the coal hydrogasification unit 10, realizes the hydrogen supply and demand balance of the coal hydrogasification system, and reduces coal gasification. The hydrogen gasification system requires less external hydrogen, thus saving costs.

Furthermore, the coal hydrogenation gasification system provided by the embodiment of the present invention utilizes coal hydrogenation gasification reaction The obtained semi-coke with higher carbon content generates hydrogen-containing product gas, which provides raw material gas for the coal hydrogasification reaction in the coal hydrogasification unit 10. Compared with the direct combustion of semi-coke in the prior art, it reduces Energy waste, and reduce environmental pollution.

In the above-mentioned embodiment, after coal hydrogasification reaction occurs in the coal hydrogasification unit 10, the raw coal powder and hydrogen-containing reaction gas, the obtained semi-coke is porous particles with weak hydrophilicity, so only semi-coke is used. The concentration of the obtained semi-coke coal-water slurry is relatively low (about 40%), therefore, in order to improve the slurry concentration of semi-coke coal-water slurry, semi-coke can be ground to obtain semi-coke powder, and in the semi-coke coal-water slurry Slurry coal powder made from raw coal will also be added to the slurry, and the slurry concentration of semi-coke coal-water slurry will be increased by grading the semi-coke powder and pulping coal powder. The preparation process of semi-coke coal-water slurry can adopt two methods: dry pulping and wet pulping.

When adopting the mode of dry pulping to prepare semi-coke coal-water slurry, please refer to Fig. 7, semi-coke coal-water slurry preparation unit 20 includes: semi-coke is ground to obtain the semi-coke grinding of semi-coke powder of smaller average particle size device 21, and a pulverized coal grinding device 22 for grinding raw coal to obtain pulped coal powder with a larger average particle size.

For specific implementation, please refer to Figure 8, the semi-coke output by the coal hydrogasification unit 10 is placed in the semi-coke grinding device 21, and the semi-coke powder is ground in the semi-coke grinding device 21; the raw coal is first placed in the drying device 25 The moisture content of the dried raw coal is less than or equal to 8%; the raw coal dried by the drying device 25 is placed in the crushing device 26, and is crushed in the crushing device 26 into particles with a particle size of less than or equal to 10mm. Raw coal particles; the dried and crushed raw coal particles are placed in the coal powder grinding device 22, and the initial coal powder is ground in the coal powder grinding device 22, and the initial coal powder passes through the vibrating sieve 27 to obtain pulping coal that meets the requirements Coarse coal powder that does not meet the requirements is returned to the coal powder grinding device 22 to continue grinding; semi-coke powder and pulping coal powder are put into the mixing pulping device 24 in a certain proportion, inject a certain amount of water, and stir evenly , that is, the semi-coke coal water slurry is produced.

The semi-coke is ground into semi-coke powder, and the coal is ground into pulped coal powder, and the average particle size of the semi-coke powder is smaller than the average particle size of the pulped coal powder, and the semi-coke powder with a smaller average particle size is compared with the particle size Large pulping coal powders are mixed with each other, and through particle size gradation, semi-coke powder with a smaller average particle size is filled in the gaps of pulping coal powder with a larger average particle size, thereby increasing the slurry concentration of semi-coke coal-water slurry , and improve the stability and fluidity of semi-coke coal water slurry.

It is worth mentioning that semi-coke with porous particles is mainly formed due to the rapid expansion of raw coal powder in the process of coal hydrogasification reaction, so semi-coke is easier to grind, while raw coal is more difficult to grind than semi-coke Therefore, according to the grindability of semi-coke and raw coal, the semi-coke and raw coal are ground separately, the semi-coke is ground into semi-coke powder with a smaller average particle size, and the raw coal is ground into pulped coal powder with a larger average particle size , can effectively reduce the energy consumption when grinding semi-coke and raw coal separately, and save the time when grinding semi-coke and raw coal separately.

In the above embodiments, the semi-coke grinding device 21 and the pulverized coal grinding device 22 can be selected according to the grinding difficulty of semi-coke and raw coal, for example, they can be ball mills, column mills, rod mills, autogenous mills, etc. In the embodiment of the present invention, the semi-coke grinding device 21 is a ball mill or a rod mill, and the pulverized coal grinding device 22 is a ball mill or a rod mill.

When the semi-coke coal-water slurry is prepared by wet pulping, please refer to Fig. 9, the semi-coke coal-water slurry preparation unit includes: the semi-coke is ground to obtain the semi-coke grinding device 21 of the semi-coke powder, and the semi-coke Coke powder, water and raw coal are ground simultaneously to obtain a wet grinding device 23 of semi-coke coal water slurry.

During specific implementation, the semi-coke output by the coal hydrogasification unit 10 is directly input into the semi-coke grinding device 21, and the semi-coke powder is ground in the semi-coke grinding device 21 to form semi-coke powder; the semi-coke powder is mixed with water and stirred evenly to form Semi-coke water slurry, the raw coal is placed in the crushing device 26, and is crushed into raw coal particles with a particle size of 10 mm or less in the crushing device 26, and then the raw coal particles, semi-coke water slurry and water are placed in a wet grinding device according to a certain ratio 23 to form a semi-coke coal-water slurry composed of semi-coke powder, pulping coal powder and water. In wet pulping, when raw coal is ground, wet grinding is used, which saves energy compared with dry grinding in dry pulping.

In the above embodiments, in the semi-coke coal-water slurry, the mass ratio of semi-coke powder to pulping coal powder is 1:9 to 1:1; the semi-coke coal-water slurry includes water, and water accounts for the mass of the semi-coke coal-water slurry The percentage is 30% to 40%. For example, when the mass ratio of semi-coke powder and pulping coal powder is selected as 1:9, after measurement, the slurry concentration of the prepared semi-coke coal-water slurry is 65%; when semi-coke powder and pulping coal When the mass ratio of semi-coke powder was selected as 3:7, the slurry concentration of the prepared semi-coke coal-water slurry was 62% after measurement; when the mass ratio of semi-coke powder and pulping coal powder was selected as 1:1, after It was measured that the slurry concentration of the prepared semi-coke coal water slurry was 60%. In summary, when the mass ratio of semi-coke powder and pulping coal powder is selected as 1:9 to 1:1, the slurry concentration of the prepared semi-coke coal-water slurry is greater than or equal to 60%, which meets the requirements of semi-coke coal-water slurry. The slurry is transported to the semi-coke coal-water slurry gasification unit, and meets the feed requirements of the semi-coke coal-water slurry gasification unit.

In the above examples, the average particle size of the semi-coke powder is 10 μm-50 μm; the average particle size of the pulped coal powder is 200 μm-350 μm. The semi-coke grinding device 21 grinds the semi-coke into semi-coke powder with an average particle size of 10 μm to 50 μm, which can prevent the difficulty of pulping due to the strong hydrophobicity of the semi-coke powder when the average particle size of the semi-coke powder is greater than 50 μm, At the same time, it can prevent the prolongation of grinding semi-coke due to the average particle size of the semi-coke powder being less than 10 μm; the coal powder grinding device 22 grinds the raw coal into pulped coal powder with an average particle size of 200 μm to 350 μm. The gradation effect of the pulped coal powder and the semi-coke powder with an average particle size of 10 μm to 50 μm is better, and the pulped coal powder in this particle size range is mixed with the semi-coke powder with an average particle size of 10 μm to 50 μm. The semi-coke coal water slurry has good fluidity and stability.

When adopting mode 2 to prepare semi-coke coal-water slurry, since the semi-coke has been ground by the semi-coke grinding device 21 and the wet grinding device 23 successively, the semi-coke powder obtained by grinding the semi-coke by the semi-coke grinding device 21 The average particle size may be greater than 50 μm.

It is worth pointing out that the maximum particle size of pulped coal powder is preferably less than or equal to 1000 μm, in order to prevent the reaction rate and chemical Conversion rates.

It is worth mentioning that, in the above examples, the average particle size of the semi-coke powder is 10 μm to 50 μm; the average particle size of the pulping coal powder is 200 μm to 350 μm. It is a kind of ultra-fine powder. When semi-coke coal-water slurry is prepared by dry pulping, when the raw coal is ground by the coal powder grinding device 22, some particles with a particle size equivalent to the average particle size of semi-coke powder will also be obtained. Ultrafine powder. In order to prevent the prepared semi-coke coal-water slurry from containing too much ultra-fine powder and cause the slurry concentration, fluidity and stability of the semi-coke coal-water slurry to decrease, preferably, the raw coal is ground by a pulverized coal grinding device 22 Obtain initial pulverized coal afterward, initial pulverized coal passes through vibrating sieve 27 twice, when passing through vibrating sieve 27 for the first time, the coarse coal pulverized particle size greater than the maximum particle diameter (for example 1000 μ m) of pulping pulverized coal is screened out, passes through the second vibrating sieve 27 During the secondary vibrating sieve 27, the ultra-fine powder with particle diameter equivalent to the average particle diameter of semi-coke powder (for example, particle diameter less than or equal to 45 μ m) is screened out. When preparing semi-coke coal-water slurry, semi-coke powder and pulping coal powder with a particle size equivalent to the average particle size of semi-coke powder form superfine powder, and the mass percentage of superfine powder in the solid raw material of semi-coke coal-water slurry should be 50%, that is, the superfine powder accounts for 50% of the mass sum of the semi-coke powder and pulping coal powder, so as to prevent the semi-coke coal-water slurry from containing too much ultra-fine powder and cause the slurry concentration of the semi-coke coal-water slurry, Both fluidity and stability are reduced.

In order to improve the stability and fluidity of the semi-coke coal-water slurry, in the embodiment of the present invention, additives may be added to the semi-coke coal-water slurry, and the additives account for 0.2% to 2% by mass of the semi-coke coal-water slurry. Add additives to the semi-coke coal-water slurry to prevent the semi-coke coal-water slurry from settling during transportation, and reduce the viscosity of the semi-coke coal-water slurry, thereby improving the stability and fluidity of the semi-coke coal-water slurry. Add 0.2% to 2% additives to the semi-coke coal-water slurry to prevent the increase in the preparation cost of the semi-coke coal-water slurry due to too many additives, and at the same time prevent the stability of the semi-coke coal-water slurry caused by too little additive Improvements in sex and mobility are less effective. The additive may be a naphthalenesulfonic acid-based additive.

Please continue to refer to Fig. 7, in the embodiment of the present invention, semi-coke coal-water slurry gasification unit 30 comprises coal-water slurry gasification furnace 31 and aftertreatment device, wherein, coal-water slurry gasification furnace 31 and semi-coke coal-water slurry The preparation unit 20 is communicated; the post-processing device is respectively communicated with the coal-water slurry gasification furnace 31 and the coal hydrogenation gasification unit 10; The gasified crude coal gas is fed into the post-processing device, and the hydrogen-containing product gas is obtained after post-processing by the post-processing device. The hydrogen-containing product gas is passed into the coal hydrogenation gasification unit 10 to participate in the coal hydrogenation gasification reaction.

The coal-water slurry gasification furnace 31 is provided with an oxygen-containing gas inlet pipe. Oxygen-containing gas is introduced into the furnace 31, and the oxygen-containing gas is used as a combustion-supporting gas to assist the coal-water slurry gasification reaction of the semi-coke coal-water slurry to ensure the reaction temperature.

Please continue to refer to Fig. 7, the post-processing device includes a carbon monoxide conversion device 32 and a product gas purification device 33, and the coal-water slurry gasifier 31 is connected to the carbon monoxide conversion device 3, 2 and the product gas purification device 33 in sequence, and the product gas purification device 33 is connected with the coal The hydrogenation gasification unit 10 is connected; the semi-coke gasification crude gas obtained after the coal-water slurry gasification reaction occurs in the coal-water slurry gasification furnace 31 is sequentially passed into the carbon monoxide conversion device 32 and the product gas purification device 33 , to obtain a hydrogen-containing product gas, and the hydrogen-containing product gas is passed into the coal hydrogasification unit 10 to participate in the coal hydrogasification reaction. The semi-coke gasification crude gas obtained after the coal-water slurry gasification reaction occurs in the coal-water slurry gasifier 31 mainly includes carbon monoxide and hydrogen, and the semi-coke coal-water slurry is placed in the coal-water slurry gasifier 31 The semi-coke gasification crude gas obtained after the coal-water slurry gasification reaction in the medium is passed into the carbon monoxide shift device 32, so that carbon monoxide undergoes a carbon monoxide shift reaction to generate hydrogen, and the semi-coke gasification crude gas after the carbon monoxide shift reaction passes through the product gas The purification device 33 is used to remove the gas that exists in the semi-coke gasification crude gas after the carbon monoxide shift reaction, which is not conducive to the coal hydrogasification reaction, for example, a small amount of carbon monoxide and sulfur dioxide in the semi-coke gasification crude gas after the carbon monoxide shift reaction Wait for removal.

Please continue to refer to FIG. 7, in the coal hydrogasification system provided by the embodiment of the present invention, the coal hydrogasification unit 10 includes a semi-coke cooling and depressurization device 16 for cooling and depressurizing the semi-coke obtained after the coal hydrogasification reaction , the semi-coke cooling and depressurization device 16 communicates with the semi-coke coal-water slurry preparation unit 20 . The semi-coke obtained from the coal hydrogasification reaction is cooled and depressurized by the semi-coke cooling and pressure reducing device 16 , and then passed into the semi-coke coal-water slurry preparation unit 20 . The semi-coke cooling and depressurization device 16 is set to lower the temperature and pressure of the semi-coke obtained from the coal hydrogasification reaction, which can prevent the semi-coke from being transported to the semi-coke coal-water slurry preparation unit 20 due to the high temperature and pressure. The difficulty of pulping increases, which facilitates the pulping operation in the semi-coke coal-water slurry preparation unit 20 .

Please continue to refer to Fig. 2, the coal hydrogenation gasification unit 10 includes a coal hydrogenation gasification furnace 11 and a gas purification and separation device, the crude gas outlet of the coal hydrogenation gasification furnace 11 communicates with the gas purification and separation device, and the raw coal powder and hydrogen-containing reaction gas Coal hydrogenation gasification crude gas is also obtained after the coal hydrogenation gasification reaction is carried out in the coal hydrogenation gasifier 11, and the coal hydrogenation gasification crude gas is passed into the gas purification and separation device, and the hydrogen-containing residue obtained after purification and separation by the gas purification and separation device The gas is passed into the coal hydrogenation gasification furnace 11 to participate in the coal hydrogenation gasification reaction.

For example, the gas purification and separation device includes a dust removal device 12, a heat exchange device 13, an oil extraction device 14, and a hydrogen separation device 15. The crude gas outlet of the coal hydrogenation gasifier 11 is connected to the dust removal device 12 and the heat exchange device 13 in sequence. The heat release side, the oil extraction device 14 and the hydrogen separation device 15, the outlet of the endothermic side of the heat exchange device 13 communicates with the coal hydrogenation gasifier 11, and the inlet of the endothermic side of the heat exchange device 13 communicates with the hydrogen separation device 15 And semi-coke coal water slurry gasification unit 30.

During specific implementation, raw coal powder and hydrogen-containing reaction gas are subjected to coal hydrogenation gasification reaction in coal hydrogenation gasifier 11 to obtain coal hydrogenation gas containing light oil products (such as benzene, toluene, naphthalene, etc.), methane and hydrogen Coal hydrogenation gasification crude gas obtained by coal hydrogenation gasification reaction is passed into the dust removal device 12, and the fine particle semi-coke entrained in the coal hydrogenation gasification crude gas is filtered through the dust removal device 12; the coal hydrogenation gas after dust removal The crude coal gas passes into the heat release side of the heat exchange device 13, exchanges heat with the gas in the heat absorption side of the heat exchange device 13, preheats the gas in the heat absorption side, and makes the gas discharged from the outlet of the heat absorption side The temperature of the gas reaches about 600°C, and the coal hydrogenated gasification crude gas after dedusting cools down to form coal hydrogenated gasification crude gas with lowered temperature; The extraction device 14 extracts the light oil products from the coal hydrogasification crude gas with reduced temperature; The gas unfavorable to the coal hydrogasification reaction is separated from the coal hydrogenation gasification crude gas after the light oil product, and the hydrogen-containing residual gas is obtained. The hydrogen-containing residual gas is passed into the heat-absorbing side of the heat exchange device 13. After the heat exchange in 13, it leads to the coal hydrogenation gasifier 11, which is used as the raw material gas of the hydrogen-containing reaction gas, and participates in the coal hydrogenation gasification reaction, and the coal hydrogenation gasification crude gas after the light oil product is extracted through the hydrogen separation device 15 After processing, methane is also obtained. The gas in the heat-absorbing side of the heat exchange device 13 includes the hydrogen-containing product gas output from the semi-coke coal-water slurry gasification unit 30 , the hydrogen-containing residual gas output from the hydrogen gas separation device 15 , and external hydrogen gas.

The coal hydrogenation gasification crude gas obtained from the coal hydrogasification reaction is processed by the gas purification and separation device to obtain hydrogen-containing residual gas, and the hydrogen-containing residual gas is passed into the coal hydrogenation gasification furnace 11 to participate in the coal hydrogenation gasification reaction, realizing the hydrogen gas The high-efficiency recycling utilization reduces the demand for external hydrogen in the coal hydrogenation gasification system and saves costs.

The gas purification and separation device includes a heat exchange device 13. Coal hydrogenation and gasification raw coal gas passes into the heat release side of the heat exchange device 13, and exchanges heat with the gas in the heat absorption side of the heat exchange device 13, so that the heat exchange device 13 The gas in the heat-absorbing side is preheated, that is, the hydrogen-containing reaction gas participating in the coal hydrogasification reaction is preheated, so as to prevent the temperature of the hydrogen-containing reaction gas leading to the coal hydrogasification furnace 11 from being lowered. The temperature of the coal hydrogasification reaction. In addition, by setting the heat exchange device 13, the preheating equipment for preheating the hydrogen-containing reaction gas leading to the coal hydrogenation gasification furnace 11 can be reduced, thereby saving energy and simplifying the structure of the coal hydrogenation gasification system.

The semi-coke coal-water slurry gasification unit 30 is communicated with the inlet of the heat-absorbing side of the heat exchange device 13, even if the product gas purification device 33 is communicated with the inlet of the heat-absorbing side of the heat exchange device 13, the semi-coke gasification raw gas is in carbon monoxide The conversion reaction occurs in the conversion device 32, and after being processed by the product gas purification device 33, the obtained hydrogen-containing product gas is passed into the heat-absorbing side of the heat exchange device 13, and is hydrogenated and gasified with the dedusted coal in the heat exchange device 13 After heat exchange, the crude gas is passed to the coal hydrogenation gasifier, which improves the reaction rate and chemical conversion rate of the coal hydrogenation gasification reaction.

It is worth mentioning that the coal hydrogenation gasification crude gas after the light oil product is extracted by the oil extraction device 14 can be directly passed into the product gas purification device 33 in the semi-coke coal-water slurry gasification unit 30, and purified by the product gas After the device 33 is purified, it is passed into the heat exchange device 13. At this time, the setting of the hydrogen separation device 15 can be cancelled.

In the above embodiments, the coal hydrogasification furnace 11 is provided with a chilling device for cooling the coal hydrogasification crude gas obtained after the coal hydrogasification reaction. The coal hydrogenation gasification crude gas obtained after the coal hydrogasification reaction is cooled by the quenching device and then passed into the gas purification and separation device. A chilling device is installed in the coal hydrogasification furnace 11 to cool the coal hydrogasification crude gas obtained from the coal hydrogasification reaction, so as to prevent the light oil in the coal hydrogasification crude gas from occurring at high temperature. break down.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (17)

1. A coal hydro-gasification process, comprising:

a coal hydro-gasification process, namely performing coal hydro-gasification reaction on raw coal powder and hydrogen-containing reaction gas in a coal hydro-gasification unit to obtain semicoke;

a semicoke coal water slurry preparation step, wherein a semicoke coal water slurry preparation unit prepares semicoke coal water slurry by using semicoke obtained in the coal hydro-gasification step;

and a semicoke coal water slurry gasification procedure, wherein the semicoke coal water slurry is subjected to coal water slurry gasification reaction in a semicoke coal water slurry gasification unit to obtain semicoke gasified raw gas, the semicoke gasified raw gas is subjected to post-treatment to obtain hydrogen-containing product gas, and the hydrogen-containing product gas is introduced into the coal hydro-gasification unit to participate in the coal hydro-gasification reaction.

2. The coal hydrogasification method according to claim 1, wherein the semicoke coal-water slurry comprises semicoke powder and slurrying pulverized coal, the semicoke coal-water slurry preparation unit comprises a semicoke grinding device and a pulverized coal grinding device, and the semicoke coal-water slurry preparation process comprises:

grinding, namely grinding the semicoke obtained in the coal hydro-gasification process by using the semicoke grinding device to form semicoke powder, grinding the raw coal by using the coal powder grinding device to form slurried coal powder, wherein the average particle size of the slurried coal powder is larger than that of the semicoke powder;

and a semi-coke coal water slurry preparation step, namely uniformly mixing the semi-coke powder, the pulping coal powder and water to prepare the semi-coke coal water slurry.

3. The coal hydrogasification method according to claim 1, wherein the semicoke coal-water slurry comprises semicoke powder and slurrying pulverized coal, the semicoke coal-water slurry preparation unit comprises a semicoke grinding device and a wet grinding device, and the semicoke coal-water slurry preparation process comprises:

a char grinding step of grinding, by the char grinding device, char obtained in the coal hydro-gasification process to form char powder;

a semi-coke water slurry preparation step, namely mixing semi-coke powder with water and uniformly stirring to prepare semi-coke water slurry;

and a semi-coke coal water slurry preparation step, wherein the semi-coke water slurry, the raw coal and the water are ground by the wet grinding device to form the semi-coke coal water slurry.

4. The coal hydro-gasification method according to claim 2 or 3, wherein in the semi-coke coal-water slurry, the mass ratio of semi-coke powder to pulping coal powder is 1: 9-1: 1;

in the semicoke coal water slurry, the water accounts for 30-40% of the semicoke coal water slurry by mass percent.

5. The coal hydrogasification method according to claim 2 or 3, wherein in the semi-coke coal-water slurry, the average particle size of the semi-coke powder is 10 μm to 50 μm; the average grain diameter of the pulping coal powder is 200-350 μm.

6. The coal hydrogasification method of claim 1, wherein the semicoke coal-water slurry further comprises an additive, and the additive accounts for 0.2-2% of the semicoke coal-water slurry by mass.

7. The coal hydro-gasification method according to claim 6, wherein the additive is a naphthalene sulfonic acid-based additive.

8. The coal hydrogasification method according to claim 1, wherein the semicoke coal-water slurry gasification unit comprises a coal-water slurry gasification furnace and a post-treatment device, and the semicoke coal-water slurry gasification process comprises:

a semicoke coal water slurry gasification step, namely putting semicoke coal water slurry and oxygen-containing gas into the coal water slurry gasification furnace, so that the semicoke coal water slurry generates a coal water slurry gasification reaction in the coal water slurry gasification furnace to obtain semicoke gasified raw gas;

and a step of after-treatment of the crude gas, which is to introduce the semicoke gasified crude gas into the after-treatment device, carry out after-treatment on the semicoke gasified crude gas by the after-treatment device to obtain a hydrogen-containing product gas, and introduce the hydrogen-containing product gas into the coal hydro-gasification unit to participate in the coal hydro-gasification reaction.

9. The coal hydrogasification method according to claim 1, wherein the coal hydrogasification unit comprises a coal hydrogasification furnace, a semicoke cooling and depressurizing device, and a gas purification and separation device, wherein a coal gas chilling device is provided in the coal hydrogasification furnace, and the coal hydrogasification process comprises:

carrying out coal hydrogenation gasification reaction on raw coal powder and hydrogen-containing reaction gas in the coal hydrogenation gasification furnace to obtain semicoke and coal hydrogenation gasification raw gas;

cooling and depressurizing the semicoke obtained by the coal hydro-gasification reaction through the semicoke cooling and depressurizing device, and leading the semicoke subjected to cooling and depressurization into the semicoke coal water slurry preparation unit;

and the crude coal gas after coal hydrogenation gasification is chilled by the coal gas chilling device and then is introduced into the gas purification and separation device, the crude coal gas after being chilled by the coal gas chilling device is purified and separated by the gas purification and separation device to obtain residual gas containing hydrogen, and the residual gas containing hydrogen is introduced into the coal hydrogenation gasification furnace to participate in the coal hydrogenation gasification reaction.

10. A coal hydrogasification system is characterized by comprising a coal hydrogasification unit, a semicoke coal water slurry preparation unit and a semicoke coal water slurry gasification unit; wherein,

the coal hydro-gasification unit is used for carrying out coal hydro-gasification reaction on raw coal powder and hydrogen-containing reaction gas to obtain semicoke;

the semicoke coal water slurry preparation unit is communicated with the coal hydro-gasification unit and is used for preparing semicoke coal water slurry by using semicoke output by the coal hydro-gasification unit;

the semicoke coal water slurry gasification unit is respectively communicated with the semicoke coal water slurry preparation unit and the coal hydro-gasification unit and is used for carrying out coal water slurry gasification reaction on the semicoke coal water slurry output by the semicoke coal water slurry preparation unit to obtain semicoke gasified raw gas, carrying out post-treatment on the semicoke gasified raw gas to obtain hydrogen-containing product gas, and introducing the hydrogen-containing product gas into the coal hydro-gasification unit to participate in the coal hydro-gasification reaction.

11. The coal hydro-gasification system of claim 10 wherein the semi-coke coal-water slurry preparation unit comprises: the device comprises a semicoke grinding device for grinding semicoke to obtain semicoke powder with smaller average particle size and a coal powder grinding device for grinding raw coal to obtain slurrying coal powder with larger average particle size.

12. The coal hydro-gasification system of claim 10 wherein the semi-coke coal-water slurry preparation unit comprises: the device comprises a semicoke grinding device for grinding semicoke to obtain semicoke powder and a wet grinding device for grinding semicoke powder, water and raw coal simultaneously to obtain semicoke coal water slurry.

13. The coal hydrogasification system of claim 10, wherein the semicoke coal-water slurry gasification unit comprises a coal-water slurry gasification furnace and a post-treatment device, wherein the coal-water slurry gasification furnace is communicated with the semicoke coal-water slurry preparation unit; the post-treatment device is respectively communicated with the semicoke coal-water slurry gasification furnace and the coal hydro-gasification unit; and introducing semicoke gasification raw gas obtained after the semicoke coal water slurry is subjected to coal water slurry gasification reaction in the coal water slurry gasification furnace into the post-treatment device, carrying out post-treatment by the post-treatment device to obtain hydrogen-containing product gas, and introducing the hydrogen-containing product gas into the coal hydro-gasification unit to participate in the coal hydro-gasification reaction.

14. The coal hydrogasification system of claim 13, wherein the post-treatment device comprises a carbon monoxide shift device and a product gas purification device, the coal-water slurry gasification furnace is sequentially communicated with the carbon monoxide shift device and the product gas purification device, and the product gas purification device is communicated with the coal hydrogasification unit; and (3) introducing semicoke gasification raw gas obtained after the semicoke coal water slurry is subjected to coal water slurry gasification reaction in the coal water slurry gasification furnace into the carbon monoxide conversion device and the product gas purification device in sequence to obtain hydrogen-containing product gas, and introducing the hydrogen-containing product gas into the coal hydro-gasification unit to participate in the coal hydro-gasification reaction.

15. The coal hydrogasification system of claim 10, wherein the coal hydrogasification unit comprises a semicoke cooling depressurization device for cooling and depressurizing semicoke obtained after the coal hydrogasification reaction, and the semicoke cooling depressurization device is communicated with the semicoke coal-water slurry preparation unit.

16. The coal hydrogasification system according to claim 10, wherein the coal hydrogasification unit includes a coal hydrogasification furnace and a gas purification and separation device, a raw gas outlet of the coal hydrogasification furnace is communicated with the gas purification and separation device, raw coal powder and hydrogen-containing reaction gas also obtain coal hydrogasification raw gas after coal hydrogasification reaction in the coal hydrogasification furnace, the coal hydrogasification raw gas is introduced into the gas purification and separation device, and hydrogen-containing residual gas obtained after purification and separation by the gas purification and separation device is introduced into the coal hydrogasification furnace to participate in the coal hydrogasification reaction.

17. The coal hydrogasification system of claim 16, wherein a chilling device for cooling the raw coal gas obtained after the coal hydrogasification reaction is disposed in the coal hydrogasification furnace.