Gasification type material as well as preparation method and application thereof

Abstract

The invention discloses a gasified briquette and a preparation method and application thereof, the gasified briquette comprises enriched carbon subjected to oxidation pretreatment and a binder, the enriched carbon is an organic carbon residue enriched product obtained from coal gasified slag through a separation technology, and the binder comprises coal liquefaction residue raffinate and coal tar. According to the gasification briquette, the gasification briquette is prepared by combining the gasified slag separated and enriched carbon subjected to oxidation pretreatment, the coal liquefaction residue raffinate and the coal tar and can be used as a fixed bed gasification raw material, and the gasification performance of the gasification briquette can be remarkably improved. The method realizes resource high-value utilization of bulk solid waste coal gasification slag and coal liquefaction slag in the coal chemical industry, is green and environment-friendly, reduces the cost, and has wide market economic prospects.

Description

Technical Field

[0001] The present invention relates to the field of comprehensive utilization of coal chemical solid waste, and in particular to a gasification profile and a preparation method and application thereof. Background Art

[0002] Clean and efficient utilization of coal is of great significance. Coal gasification and liquefaction technology is of great strategic significance for leveraging the advantages of coal resources, alleviating the tension in oil resources, ensuring energy security and protecting the ecological environment.

[0003] The coal gasification process produces a large amount of solid waste - gasification slag. The annual emission of gasification slag is huge, of which gasification fine slag accounts for 20-40% of the total gasification slag, and the loss on combustion is as high as 20-30%. Usually, gasification slag can only be landfilled or piled up, resulting in a waste of resources. The leakage of heavy metals will also cause soil and water pollution. Due to the high toxicity components of gasification slag, low reaction activity, and difficulty in large-scale comprehensive utilization, the comprehensive utilization rate is only about 31.6%.

[0004] Coal direct liquefaction technology produces gasoline and diesel, and the by-product coal liquefaction residue is about 30% of the mass of the raw coal. Traditional gasification, coking and combustion do not reflect the high added value utilization potential of liquefied residue. The preparation of high-end carbon materials from coal liquefaction residue is currently a hot topic in the field of coal direct liquefaction technology. The key to the realization of this process lies in the efficient and deep deashing of the residue. The 350,000 t / a liquefied residue extraction and preparation of high-medium-low grade asphalt unit put into operation by the State Energy Group in the Ordos million-ton coal direct liquefaction plant has achieved high-value utilization of part of the liquefied residue of the liquefaction plant. At the same time, more than 170,000 tons of liquefied residue extracts are produced as a by-product each year. After the large plant dries these extracts and recovers the solvent, more than 90% of the particle size is less than 40μm. Long-term stacking is likely to cause dust pollution in the park and bring explosion risks to external transportation. Summary of the invention

[0005] The present invention is based on the inventor's discovery and understanding of the following facts and problems: gasification slag can only be landfilled or piled up, resulting in a waste of resources, and the leakage of heavy metals will also cause soil and water pollution; in addition, gasification slag has high toxic components, low reaction activity, and is difficult to be comprehensively utilized on a large scale, with a comprehensive utilization rate of only about 31.6%. Long-term stacking of dried liquefied residues is likely to cause dust pollution in the park and bring the risk of explosion during transportation. Undried liquefied residues are viscous, have an odor, pollute the environment, and are difficult to transport.

[0006] The separation technology is used to separate the carbon ash from the gasification slag to obtain the graded utilization of enriched carbon and inorganic ash. The carbon content in the enriched carbon can reach more than 70%, and it has the characteristics of low volatile matter, high degree of graphitization, and a certain pore structure. The enriched carbon is converted into synthesis gas through gasification technology, which can achieve its large-scale, resource-based, low-carbon and harmless utilization. The enriched carbon has poor reaction activity, while the fixed bed gasification technology has the characteristics of long material residence time and no material entrainment, and is expected to achieve complete conversion of residual carbon in the enriched carbon. However, most of the enriched carbon particles are less than 100μm, which cannot meet the requirements of the fixed bed gasifier for the raw material particle size, so the enriched carbon molding problem needs to be solved.

[0007] Compared with liquefied residue, the liquefied residue extract has the physical characteristics of high ash, high iron and high viscosity, and contains a certain amount of heavy oil and asphalt. From the perspective of energy utilization and economic benefits, the demand for extract disposal covers gasification, pyrolysis and combustion. In particular, the forming gasification of extract can form a high-value disposal technology for solid waste, and can provide the required raw hydrogen for coal-to-liquid production equipment, which can replace part of the gasification raw coal, forming the effect of circular economy and closed-loop technology for high-value utilization of residue.

[0008] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the embodiments of the present invention propose a gasification profile and a preparation method and application thereof, wherein the gasification profile is prepared by combining the oxidatively pretreated gasification slag sorting and enrichment of carbon, the coal liquefaction residue extract and coal tar, which can be used as a fixed bed gasification raw material and can significantly improve the gasification performance of the gasification profile. The present invention realizes the resource-based high-value utilization of coal gasification slag and coal liquefaction slag, which are large-scale solid wastes of coal chemical industry, is green and environmentally friendly, reduces costs, and has broad market economic prospects.

[0009] The embodiment of the present invention provides a gasification profile, comprising: oxidatively pretreated enriched carbon and a binder, wherein the enriched carbon is an organic carbon residue enrichment obtained by sorting coal gasification slag, and the binder comprises coal liquefaction residue extract and coal tar.

[0010] The advantages and technical effects brought by the gasification profile of the embodiment of the present invention are as follows: the organic residual carbon enriched product - enriched carbon obtained by sorting the gasification slag is used as the raw material, and the gasification profile is prepared together with the adhesive coal liquefaction residue and coal tar, which can be used as a fixed bed gasification raw material, and can significantly improve the gasification performance of the gasification profile.

[0011] In the embodiment of the present invention, the gasified slag is sorted and ash is removed to obtain enriched carbon, which has low reaction activity, developed pore structure and large specific surface area, and is a cheap and easy-to-obtain special carbon source. The raw material enriched carbon comes from gasification. After being tempered at high temperature in the gasifier, it has low volatile matter and poor activation reaction performance. The present invention adopts oxidation pretreatment to selectively oxidize the fat structure (such as side chain, bridge bond, etc.) in the enriched carbon to generate more oxygen-containing functional groups, which is conducive to amplifying the active sites of the enriched carbon, and can improve the reaction activity of the enriched carbon, thereby improving the gasification performance of the gasification profile.

[0012] In the embodiment of the present invention, the coal liquefaction residue extract has suitable fluidity and adhesiveness, and can be used together with coal tar as a binder. By cooperating with the enriched carbon pretreated by oxidation, a molding material is obtained, which meets the index requirements of the fixed bed gasifier raw material. The gasification catalytic effect of metals such as iron, alkali metals and alkaline earth metals in the coal liquefaction residue extract is conducive to promoting the catalytic gasification reaction of the enriched carbon, further improving the gasification activity of the gasification slag enriched carbon, and then improving the gasification performance of the gasification molding material. There are also heavy components and unreacted coal in the coal liquefaction residue extract, which can be gasified to achieve high-value resource utilization of the coal liquefaction residue extract. The gasification slag has a developed pore structure, a large specific surface area, large elasticity, poor plasticity, and poor formability. The molding material is easy to disperse under high temperature conditions, which is not conducive to the gasification reaction. The addition of coal tar can improve the thermal strength of the gasification molding material and maintain the molding state of the gasification molding material at high temperature.

[0013] In the embodiments of the present invention, the resource utilization of large solid wastes from coal chemical industry is realized, waste is treated with waste, and waste is eliminated. The bonding characteristics of coal liquefaction residue extract are utilized to realize the combined granulation with gasification slag enriched carbon for fixed bed gasification, which solves the problem of gasification slag accumulation and landfill occupying land resources and seriously damaging the ecological environment, and realizes the high-value resource utilization of coal liquefaction residue extract, which has broad market economic prospects.

[0014] In some embodiments, the mass ratio of the oxidative pretreated enriched carbon, the coal liquefaction residue extract and the coal tar is 100:10-20:5-10.

[0015] In some embodiments, the ash content of the enriched carbon is ≤15%;

[0016] and / or, the particle size of the oxidatively pretreated enriched carbon is ≤0.154 mm;

[0017] And / or, the separation technology includes at least one of flotation, gravity separation, electrostatic separation, and combustion;

[0018] And / or, the temperature of the oxidation pretreatment is 260-350°C;

[0019] And / or, the oxidation pretreatment time is 3 to 16 hours.

[0020] In some embodiments, the coal liquefaction residue extract comprises, by mass: asphaltene: 5-25%; heavy oil: 10-20%; ash: 20-35%; the rest is coke powder and / or coal powder;

[0021] And / or, the coal liquefaction residue extract comprises metal elements, and the metal elements comprise at least one of iron, alkali metals and alkaline earth metals; and the mass percentage of the metal elements in the coal liquefaction residue extract is 1-10%.

[0022] In some embodiments, coal is also included.

[0023] In some embodiments, the mass ratio of the oxidatively pretreated enriched carbon to coal is 100:5-15;

[0024] and / or, the coal comprises at least one of lignite or long flame coal;

[0025] and / or, the ash content of the coal is ≤10%;

[0026] and / or, the sulfur content of the coal is <1%;

[0027] And / or, the particle size of the coal is ≤0.154 mm.

[0028] In some embodiments, the binder also includes other binders other than coal liquefaction residue and coal tar; the other binders include at least one of organic binders, inorganic binders or composite binders; the mass ratio of the other binders to the coal liquefaction residue is 5 to 35:100.

[0029] In some embodiments, the particle size of the gasified material is 5 to 50 mm;

[0030] And / or, the cold pressing strength of the gasified profile is not less than 380N / piece;

[0031] And / or, the hot pressing strength of the gasified profile is not less than 230N / piece;

[0032] And / or, the thermal stability TS of the gasified material +13 >50%;

[0033] And / or, the gasification carbon conversion rate of the gasification profile is not less than 96%.

[0034] The embodiment of the present invention provides a method for preparing a gasified profile, comprising the following steps:

[0035] (1) subjecting the enriched carbon to oxidation pretreatment to obtain oxidatively pretreated enriched carbon;

[0036] (2) The oxidatively pretreated enriched carbon is mixed with water, then mixed with a binder, and extruded to obtain a gasification profile.

[0037] In the embodiment of the present invention, the oxidation pretreatment can promote the generation of more oxygen-containing functional groups on the surface of the enriched carbon, which is beneficial to expand the active sites of the enriched carbon and improve the reaction activity of the enriched carbon. The liquefied coal residue has fluidity and adhesiveness, and can be used as a binder with coal tar, and extruded with the oxidatively pretreated enriched carbon to obtain a molding material. Appropriate moisture acts as a lubricant during the molding process, reduces the friction inside the molding system, and is beneficial to improving the strength of the molding material. Due to the pressure applied by the extrusion molding machine, the volume of the oxidatively pretreated enriched carbon shrinks and becomes dense, forming a gasified molding material, which is beneficial to improving the strength.

[0038] In some embodiments, in step (1), the temperature of the oxidation pretreatment is 260-350°C;

[0039] And / or, in step (1), the oxidation pretreatment time is 3 to 16 hours;

[0040] And / or, in the step (2), the mass ratio of the oxidatively pretreated enriched carbon to water is 100:5-10;

[0041] And / or, the step (2) further comprises coal, mixing the oxidatively pretreated enriched carbon, coal and water; the mass ratio of the oxidatively pretreated enriched carbon and coal to water is 100:5-10;

[0042] And / or, in step (2), the temperature of mixing with water is 80-90°C;

[0043] And / or, in step (2), the temperature of mixing with the binder is 120-180°C;

[0044] And / or, in the step (2), the coal liquefaction residue extract in the binder is obtained by extracting and centrifuging the coal liquefaction residue; the centrifuge speed is 3000-5000 rpm; the centrifuge temperature is 100-180°C;

[0045] And / or, in step (2), the extrusion molding pressure is 16 to 22 MPa;

[0046] And / or, in step (2), the moisture content of the gasified material is less than 5%.

[0047] The embodiment of the present invention provides an application of a gasification profile, wherein the gasification profile is used for fixed bed gasification. In the embodiment of the present invention, the gasification profile meets the fixed bed gasification raw material index requirements, can be used as a fixed bed gasification raw material, and has high gasification reaction activity. The gasification profile realizes the resource-based high-value utilization of coal gasification slag and coal liquefaction slag, which are large-scale solid wastes of coal chemical industry, are green and environmentally friendly, reduce costs, and have broad market economic prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 This is an appearance diagram of the enriched carbon of Example 1 of the present invention.

[0049] Figure 2 This is a microscopic SEM image of the enriched carbon of Example 1 of the present invention.

[0050] Figure 3 This is an appearance diagram of the gasification molding material of Example 1 of the present invention. DETAILED DESCRIPTION

[0051] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0052] A gasification material according to an embodiment of the present invention comprises: enriched carbon pretreated by oxidation and a binder, wherein the enriched carbon is an organic carbon residue enrichment obtained by sorting coal gasification slag, and the binder comprises coal liquefaction residue extract and coal tar.

[0053] The gasification profile of the embodiment of the present invention is prepared by combining the organic residual carbon enrichment - enriched carbon obtained by sorting gasification slag with adhesive coal liquefaction residue and coal tar, which can be used as a fixed bed gasification raw material and can significantly improve the gasification performance of the gasification profile.

[0054] In the embodiment of the present invention, the gasified slag is sorted and ash is removed to obtain enriched carbon, which has low reaction activity, developed pore structure and large specific surface area, and is a cheap and easy-to-obtain special carbon source. The raw material enriched carbon comes from gasification. After being tempered at high temperature in the gasifier, it has low volatile matter and poor activation reaction performance. The present invention adopts oxidation pretreatment to selectively oxidize the fat structure (such as side chain, bridge bond, etc.) in the enriched carbon to generate more oxygen-containing functional groups, which is conducive to amplifying the active sites of the enriched carbon, and can improve the reaction activity of the enriched carbon, thereby improving the gasification performance of the gasification profile.

[0055] In the embodiment of the present invention, the coal liquefaction residue extract has suitable fluidity and adhesiveness, and can be mixed with coal tar as a binder. By cooperating with the enriched carbon pretreated by oxidation, a molding material is obtained, which meets the index requirements of the fixed bed gasifier raw material. The gasification catalytic effect of metals such as iron, alkali metals and alkaline earth metals in the coal liquefaction residue extract is conducive to promoting the catalytic gasification reaction of the enriched carbon, further improving the gasification activity of the gasification slag enriched carbon, and then improving the gasification performance of the gasification molding material. There are also heavy components and unreacted coal in the coal liquefaction residue extract, which can be gasified to achieve high-value resource utilization of the coal liquefaction residue extract. The gasification slag has a developed pore structure, a large specific surface area, large elasticity, poor plasticity, and poor formability. The molding material is easy to disperse under high temperature conditions, which is not conducive to the gasification reaction. The addition of coal tar can improve the thermal strength of the gasification molding material and maintain the molding state of the gasification molding material at high temperature.

[0056] In the embodiments of the present invention, the resource utilization of large solid wastes from coal chemical industry is realized, waste is treated with waste, and waste is eliminated. The bonding characteristics of coal liquefaction residue extract are utilized to realize the combined granulation with gasification slag enriched carbon for fixed bed gasification, which solves the problem of gasification slag accumulation and landfill occupying land resources and seriously damaging the ecological environment, and realizes the high-value resource utilization of coal liquefaction residue extract, which has broad market economic prospects.

[0057] In some embodiments, the gasified slag includes gasified fine slag. In an embodiment of the present invention, the gasified slag is gasified fine slag.

[0058] In some embodiments, the mass ratio of the oxidatively pretreated enriched carbon to the binder is 100:15-30, specifically, for example, 100:15, 100:20, 100:25, 100:30.

[0059] In some embodiments, the mass ratio of the oxidatively pretreated enriched carbon, the coal liquefaction residue extract and the coal tar is 100:10-20:5-10, specifically, 100:10-20 (for example, 10, 12, 14, 16, 18, 20):5-10 (for example, 5, 6, 7, 8, 9, 10). In the embodiments of the present invention, by adjusting the ratio of the oxidatively pretreated enriched carbon, the coal liquefaction residue extract and the coal tar, it is beneficial to further improve the gasification performance of the gasification profile. When the amount of the coal liquefaction residue extract is too low, the bonding performance and gasification catalytic effect of the extract cannot be fully exerted; the ash content of the coal liquefaction residue extract is 20-35%. When the amount of the coal liquefaction residue extract is too high, the gasification intensity is affected.

[0060] In some embodiments, the ash content of the enriched carbon is ≤15%; the enriched carbon is an organic residual carbon concentrate obtained by sorting coal gasification slag. The present invention has no special restrictions on the sorting technology, and the ash can be removed by sorting. For example, the sorting technology includes at least one of flotation, gravity separation, electrostatic separation, and combustion. Preferably, flotation. In the embodiment of the present invention, the carbon in the gasification slag produced by coal gasification is sorted and recovered to obtain enriched carbon. There is no special restriction on the sorting method. Enriched carbon with an ash content of ≤15% can be obtained by conventional sorting methods in the art. The ash content of the enriched carbon is ≤15%, which is beneficial to improving the gasification performance of the gasification profile and improving the gasification treatment efficiency for the fixed bed.

[0061] In some embodiments, the particle size of the enriched carbon obtained by oxidation pretreatment is ≤0.154mm; optionally, the particle size is <0.154mm after 100 mesh screening. In the embodiments of the present invention, the smaller the carbon raw material particles of the gasification molding material, the smaller the internal voids of the molding material system, and the higher the cold compression strength, hot compression strength and thermal stability of the molding material. Theoretically, the particle size of the material obtained by 100 mesh screening presents a normal distribution, the large particles are evenly embedded in the fine particles, the large particles become the skeleton of the molding material, the small particles are condensed into granules under the action of the binder, and the whole is attached to the large particles, so that the molding material strength is higher.

[0062] In some embodiments, the temperature of the oxidation pretreatment is 260-350°C, specifically, for example, 260°C, 280°C, 300°C, 320°C, 350°C; the time of the oxidation pretreatment is 3-16h, specifically, for example, 3h, 5h, 8h, 10h, 12h, 14h, 16h; the oxidation pretreatment is carried out in air. In the embodiment of the present invention, the gasified slag sorting enriched carbon has low volatile matter and poor reaction activity after being tempered by the high temperature of the gasifier, and has a certain initial pore structure and a certain specific surface area. The pre-oxidation treatment of the gasified slag sorting enriched carbon can promote the generation of more oxygen-containing functional groups on the surface of the enriched carbon, which is beneficial to expand the active sites of the enriched carbon and improve the reaction activity of the enriched carbon. In the present invention, 260-350°C oxidation pretreatment of the enriched carbon is beneficial to further improve the reaction activity of the enriched carbon, while taking into account the drying of the enriched carbon, which is beneficial to powder making.

[0063] In some embodiments, the coal liquefaction residue extract includes, by mass: asphaltene: 5-25% (e.g., 5%, 10%, 15%, 20%, 25%); heavy oil: 10-20% (e.g., 10%, 12%, 15%, 18%, 20%); ash: 20-35% (e.g., 20%, 22%, 25%, 30%, 32%, 35%); the rest is coke powder and / or coal powder. Among them, the coal powder is unreacted coal powder. In the embodiment of the present invention, the coal liquefaction residue extract includes asphaltene, heavy oil and other components. The coal liquefaction residue is a black viscous solid at room temperature and has a certain fluidity above 100°C. The coal liquefaction residue extract has adhesiveness, which is conducive to being used as a binder to bond molding materials.

[0064] In some embodiments, the coal liquefaction residue extract includes metal elements, and the metal elements include at least one of iron, alkali metals, and alkaline earth metals, optionally, including iron, alkali metals and alkaline earth metals; optionally, the alkali metals include sodium and / or potassium; optionally, the alkaline earth metals include calcium; optionally, the mass percentage of metal elements in the coal liquefaction residue extract is 1-10%, specifically, for example, 1%, 2%, 3%, 4%, 5%, 7%, 8%, 10%; optionally, the iron content in the coal liquefaction residue extract is 2-6wt%, specifically, for example, 2%, 3%, 4%, 5%, 6%; the calcium content is 3-6wt%, specifically, for example, 3%, 4%, 5%, 6%. In the embodiment of the present invention, coal contains metal elements, and the coal liquefaction residue extract obtained therefrom includes metal elements, for example, iron and / or alkali metals and / or alkaline earth metal elements, with a high iron content and a certain alkali and alkaline earth metal content. The gasification catalytic effect of iron, alkali metals and alkaline earth metals is beneficial to further enhance the gasification activity of the gasification slag enriched carbon, and is beneficial to promote the catalytic gasification reaction of the enriched carbon, thereby further improving the gasification activity of the gasification material.

[0065] In some embodiments, there is no particular limitation on the coal tar.

[0066] In some embodiments, coal is also included; optionally, the mass ratio of the oxidatively pretreated enriched carbon to the coal is 100:5-15, specifically, for example, 100:5, 100:10, 100:15; the coal includes at least one of lignite or long flame coal; the ash content of the coal is ≤10%; the sulfur content of the coal is <1%; the particle size of the coal is ≤0.154mm, and optionally, the particle size <0.154mm is obtained by 100 mesh screening. In the embodiment of the present invention, compared with the enriched carbon, the gasification reaction activity of the low-rank coal is higher, which is beneficial to improve the gasification reaction performance of the molding material. The present invention can use the oxidatively pretreated enriched carbon as a raw material and combine it with the coal liquefaction residue extract-coal tar to prepare the gasification molding material, or the oxidatively pretreated enriched carbon and coal can be reasonably mixed and then combined with the liquefaction residue extract-coal tar to prepare the gasification molding material, which is used as a fixed bed gasification raw material. By adjusting the limit values ​​of ash content, sulfur content, etc. of low-rank coal and blending it with the enriched carbon pretreated by oxidation, it is helpful to further improve the quality grade of the raw material system for preparing gasification profiles.

[0067] In some embodiments, the binder also includes other binders other than coal liquefaction residue and coal tar; the other binders include at least one of an organic binder, an inorganic binder or a composite binder; preferably, the other binders include at least one of coal tar, a high molecular polymer, clay, and bentonite; the mass ratio of the other binder to the coal liquefaction residue is 5 to 35:100, specifically, for example, 5:100, 10:100, 20:100, 30:100, 35:100.

[0068] In some embodiments, the particle size of the gasified material is 5 to 50 mm, specifically, for example, 5 mm, 10 mm, 20 mm, 30 mm, 40 mm, 50 mm.

[0069] In some embodiments, there is no particular limitation on the shape of the gasification profile, for example, it can be at least one of spherical, square, and oblate.

[0070] In some embodiments, the cold compression strength of the gasified profile is not less than 380N / piece; and / or, the hot compression strength of the gasified profile is not less than 230N / piece; and / or, the thermal stability TS of the gasified profile is +13 >50%; and / or, the gasification carbon conversion rate of the gasification profile is not less than 96%, and optionally, not less than 97%. In the embodiment of the present invention, the gasification profile has excellent mechanical properties and gasification properties.

[0071] A method for preparing a gasified profile according to an embodiment of the present invention comprises the following steps:

[0072] (1) subjecting the enriched carbon to oxidation pretreatment to obtain oxidatively pretreated enriched carbon;

[0073] (2) The oxidatively pretreated enriched carbon is mixed with water, then mixed with a binder, and extruded to obtain a gasification profile.

[0074] In the embodiment of the present invention, the oxidation pretreatment can promote the generation of more oxygen-containing functional groups on the surface of the enriched carbon, which is beneficial to expand the active sites of the enriched carbon and improve the reaction activity of the enriched carbon. The liquefied coal residue has fluidity and adhesiveness, and can be used as a binder with coal tar, and extruded with the oxidatively pretreated enriched carbon to obtain a molding material. Appropriate moisture acts as a lubricant during the molding process, reduces the friction inside the molding system, and is beneficial to improving the strength of the molding material. Due to the pressure applied by the extrusion molding machine, the volume of the oxidatively pretreated enriched carbon shrinks and becomes dense, forming a gasified molding material, which is beneficial to improving the strength.

[0075] In some embodiments, in the step (1), the temperature of the oxidation pretreatment is 260-350°C, specifically, for example, 260°C, 280°C, 300°C, 320°C, 350°C; the time of the oxidation pretreatment is 3-16h, specifically, for example, 3h, 5h, 8h, 10h, 12h, 14h, 16h; the oxidation pretreatment is carried out in air. In the embodiment of the present invention, after the gasification slag sorting enriched carbon has been tempered at high temperature in the gasifier, the volatile matter is low, the reaction activity is poor, and it has a certain initial pore structure and a certain specific surface area. The pre-oxidation treatment of the gasification slag sorting enriched carbon can promote the generation of more oxygen-containing functional groups on the surface of the enriched carbon, which is beneficial to expand the active sites of the enriched carbon and improve the reaction activity of the enriched carbon. In the present invention, the 260-350°C oxidation pretreatment of the enriched carbon is beneficial to further improve the reaction activity of the enriched carbon, while taking into account the drying of the enriched carbon, which is beneficial to powder making.

[0076] In some embodiments, the enriched carbon is subjected to oxidation pretreatment, and the enriched carbon after oxidation pretreatment is ground to obtain oxidatively pretreated enriched carbon; optionally, the oxidatively pretreated enriched carbon is ground by grinding; the oxidatively pretreated enriched carbon is passed through a 100 mesh sieve, i.e., the particle size of the oxidatively pretreated enriched carbon is ≤0.154 mm.

[0077] In some embodiments, in step (2), the coal liquefaction residue in the binder is obtained by extracting and centrifuging the coal liquefaction residue;

[0078] Optionally, the extraction adopts a solvent, and the solvent includes wash oil; the rotation speed of the centrifuge is 3000-5000rpm, specifically, for example, 3000rpm, 4000rpm, 5000rpm; the temperature of the centrifuge is 100-180°C, specifically, for example, 100°C, 120°C, 150°C, 180°C. In the embodiment of the present invention, the coal liquefaction residue solvent deashing adopts a centrifugal method, and the coal liquefaction residue extract has suitable fluidity at 100-180°C. Centrifugation at 3000-5000rpm at 100-180°C can obtain a coal liquefaction residue extract containing 5-25% asphaltene, 10-20% heavy oil, 20-35% ash, and the rest is coke powder and unreacted coal powder. In addition, the coal liquefaction residue extract has suitable fluidity and adhesiveness at 100-180°C. By compounding with coal tar and non-adhesive oxidative pretreated enriched carbon to prepare gasification profiles, it can meet the particle size and quality index requirements of fixed bed gasifier raw materials, which is conducive to further improving the gasification activity of gasification profiles. The coal liquefaction residue extract has a high iron content and a certain alkali and alkaline earth metal content. Appropriate addition is conducive to promoting the catalytic gasification reaction of the enriched carbon and improving the gasification reaction activity of the enriched carbon.

[0079] In some embodiments, in step (2), the mass ratio of the oxidatively pretreated enriched carbon to the binder is 100:15-30, specifically, for example, 100:15, 100:20, 100:25, 100:30.

[0080] In some embodiments, the binder includes coal liquefaction residue and coal tar, and the mass ratio of the oxidative pretreated enriched carbon, coal liquefaction residue and coal tar is 100:10-20:5-10, specifically, 100:10-20 (for example, 10, 12, 14, 16, 18, 20):5-10 (for example, 5, 6, 7, 8, 9, 10).

[0081] In some embodiments, in step (2), the mass ratio of the oxidative pretreated enriched carbon to water is 100:5-10, specifically, for example, 100:5, 100:6, 100:7, 100:8, 100:9, 100:10. In the embodiments of the present invention, suitable moisture is conducive to improving the strength of the gasified molding material, because the moisture plays a lubricating role in the molding process, reduces the friction inside the molding system, and is conducive to improving the strength of the molding material. Too much moisture will affect the contact between the particles, and may reduce the strength of the molding material; in addition, if the molding moisture is too high, the molding material will be unable to be demolded and will stick to the ball socket; too high moisture will prolong the drying time of the molding material and reduce production efficiency.

[0082] In some embodiments, the step (2) further comprises coal, mixing the oxidatively pretreated enriched carbon, coal and water, and then mixing with a binder;

[0083] Optionally, the mass ratio of the oxidatively pretreated enriched charcoal and coal to water is 100:5-10, specifically, for example, 100:5, 100:6, 100:7, 100:8, 100:9, 100:10;

[0084] Optionally, the mass ratio of the oxidatively pretreated enriched carbon to the coal is 100:5-15, specifically, for example, 100:5, 100:10, 100:15;

[0085] Optionally, the oxidatively pretreated enriched carbon and coal are first mixed, then mixed with water, and then mixed with a binder; optionally, the mixing is performed by stirring;

[0086] Optionally, the coal is obtained by coarse crushing, drying and grinding; optionally, the drying is performed by vacuum drying; optionally, the coal is sieved through a 100-mesh sieve, that is, the particle size of the coal is ≤0.154 mm.

[0087] In some embodiments, in step (2), the temperature of mixing with water is 80-90° C., specifically, for example, 80° C., 85° C., 90° C. In the embodiments of the present invention, the mixing temperature is 80-90° C., which is beneficial to reducing the friction inside the molding system, making the mixing more uniform, and improving the strength of the molding material.

[0088] In some embodiments, in step (2), the temperature of the water is 80-90°C, specifically, for example, 80°C, 85°C, 90°C.

[0089] In some embodiments, in step (2), the temperature of the liquefied residue extract is 120-180°C, specifically, for example, 120°C, 130°C, 140°C, 150°C, 160°C, 180°C.

[0090] In some embodiments, in step (2), the temperature for mixing with the binder is 120-180° C., specifically, for example, 120° C., 130° C., 140° C., 150° C., 160° C., 180° C. In the embodiments of the present invention, the mixing temperature is 120-180° C., which is conducive to the coal liquefaction residue extract to maintain a certain fluidity and adhesion, and fully mix and infiltrate with the oxidized enriched carbon to form a uniform material, thereby meeting the fixed bed index requirements for raw materials.

[0091] In some embodiments, the mixing is performed by kneading to uniformly form the coal paste.

[0092] In some embodiments, in step (2), the extrusion molding pressure is 16 to 22 MPa, specifically, for example, 16 MPa, 18 MPa, 20 MPa, 22 MPa. In the embodiments of the present invention, the oxidized enriched carbon or the oxidized enriched carbon and coal shrink in volume and become dense due to the pressure applied by the molding machine to form a molding material. The molding pressure is the dominant factor in the compression molding, and the molding pressure has a significant effect on the strength performance of the product. The extrusion molding pressure is 16 to 22 MPa, which is conducive to improving the strength of the gasified molding material. If the molding pressure is too small, the molding material will be loose inside, which is not conducive to improving the strength of the molding material.

[0093] In some embodiments, in step (2), the shape of the gasified material is selected from at least one of spherical, square, and oblate.

[0094] In some embodiments, in the step (2), drying is performed after extrusion molding; optionally, the drying is performed by forced air drying; the drying temperature is 100-120° C., and the drying time is 1-3 hours.

[0095] In some embodiments, in step (2), the moisture content of the gasified material is <5%.

[0096] An application of a gasification profile in an embodiment of the present invention, the gasification profile is used for fixed bed gasification. In the embodiment of the present invention, the gasification profile meets the fixed bed gasification raw material index requirements, can be used as a fixed bed gasification raw material, and has high gasification reaction activity. The gasification profile realizes the resource-based high-value utilization of coal chemical industry bulk solid waste coal gasification slag and coal liquefaction slag, is green and environmentally friendly, reduces costs, and has broad market economic prospects.

[0097] The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0098] Example 1

[0099] A method for preparing a gasified material comprises the following steps:

[0100] (1) Carbon enrichment and pulverization of gasified slag from oxidation pretreatment

[0101] The ash content of 15% gasification slag is separated and enriched into carbon (such as Figure 1 and Figure 2 The oxidative pretreatment was performed at 300° C. for 8 h, and the enriched carbon after the oxidative pretreatment was ground and sieved through 100 mesh to obtain oxidative pretreated enriched carbon powder with a particle size of <0.154 mm.

[0102] (2) Preparation of coal liquefaction residue extract

[0103] The coal liquefaction residue is extracted by washing oil and centrifuged, and the centrifugal process parameters are: centrifuge speed 4000rpm, centrifuge internal temperature 150℃, to obtain coal liquefaction residue extract; the coal liquefaction residue extract contains 15% asphaltene, 10% heavy oil, 30% ash, and the rest is coke powder and unreacted coal powder.

[0104] (3) Mixing and kneading

[0105] Add 10% water of the mass of the oxidatively pretreated enriched carbon to the oxidatively pretreated enriched carbon, mix them evenly at 80°C, then add 150°C coal liquefaction residue extract and coal tar, the mass ratio of the oxidatively pretreated enriched carbon, water, coal liquefaction residue extract and coal tar is 100:10:20:5, heat the kneader to 150°C and knead evenly to form coal paste, extrude it into an oblate shape at 20MPa in a hydraulic press, the particle size range is about 20mm, dry it at 100°C for 1h to 4% moisture, and obtain a gasification profile, such as Figure 3 shown.

[0106] Example 2

[0107] A method for preparing a gasified material comprises the following steps:

[0108] (1) Carbon enrichment and pulverization of gasified slag from oxidation pretreatment

[0109] The charcoal enriched by separation of gasified slag with ash content of 15% was pre-oxidized at 300°C for 8 hours, and the charcoal enriched by oxidation pretreatment was ground and sieved with 100 meshes to obtain charcoal enriched by oxidation pretreatment with a particle size of <0.154 mm.

[0110] (2) Long flame coal

[0111] The long flame coal with ash content of 8% is roughly broken, vacuum dried, ground and sieved through 100 mesh to obtain long flame coal powder with a particle size of less than 0.154 mm.

[0112] (3) Preparation of liquefied residue extract

[0113] The coal liquefaction residue is extracted by washing oil and centrifuged, and the centrifugal process parameters are: centrifuge speed 4000rpm, centrifuge internal temperature 150℃, to obtain coal liquefaction residue extract; the coal liquefaction residue extract contains 15% asphaltene, 10% heavy oil, 30% ash, and the rest is coke powder and unreacted coal powder.

[0114] (4) Mixing and kneading

[0115] Add long flame coal powder which accounts for 10% of the mass of the oxidatively pretreated enriched carbon to the oxidatively pretreated enriched carbon, mix and stir evenly to form a mixture, then add water which accounts for 10% of the mass of the oxidatively pretreated enriched carbon, mix evenly at 80°C, then add coal liquefaction residue and coal tar at 150°C, the ratio of oxidatively pretreated enriched carbon, coal, water, coal liquefaction residue and coal tar is 100:10:10:20:5, heat the kneader to 150°C, knead evenly to form a coal paste, extrude it into an oblate shape at 20MPa in a hydraulic press, the particle size range is about 20mm, dry it at 100°C for 1h to 4% moisture, and obtain a gasification type material.

[0116] Comparative Example 1

[0117] The preparation method is the same as that of Example 1, except that in step (3), the mass ratio of the coal liquefaction residue extract and the coal tar in the binder is 20:1; and the mass ratio of the oxidative pretreated enriched carbon to the binder is still 100:25.

[0118] Comparative Example 2

[0119] The preparation method is the same as that of Example 2, except that in the step (1), the enriched carbon after oxidation pretreatment is ground and pulverized, and 20 mesh sieved to obtain oxidatively pretreated enriched carbon powder with a particle size of <0.850 mm; in the step (2), the long flame coal with an ash content of 8% is coarsely broken, vacuum dried, ground and sieved through 20 mesh to obtain long flame coal powder with a particle size of <0.850 mm.

[0120] Comparative Example 3

[0121] The preparation method is the same as that of Example 2, except that in step (4), the extrusion molding pressure in the hydraulic press is 10 MPa.

[0122] Comparative Example 4

[0123] The preparation method is the same as that of Example 1, except that in step (3), water accounting for 20% of the mass of the oxidatively pretreated enriched carbon is added to the oxidatively pretreated enriched carbon.

[0124] Comparative Example 5

[0125] The preparation method is the same as that of Example 1, except that in step (2), the centrifuge speed is 500 rpm.

[0126] Comparative Example 6

[0127] The preparation method is the same as that in Example 1, except that: in the step (1), the enriched carbon is ground and sieved through 100 mesh to obtain enriched carbon powder with a particle size of <0.154 mm, that is, the enriched carbon is not subjected to oxidation pretreatment; in the step (3), the enriched carbon is used to replace the enriched carbon subjected to oxidation pretreatment.

[0128] Comparative Example 7

[0129] The preparation method is the same as that of Example 1, except that step (2) is omitted, and in step (3), coal tar is used to replace the coal liquefaction residue extract, that is, the mass ratio of the oxidative pretreated enriched carbon, water and coal tar is 100:10:25.

[0130] Table 1 Coal quality analysis data of enriched carbon and coal liquefaction residue

[0131]

[0132]

[0133] Table 2 Ash composition analysis

[0134] <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[K2O]]> <![CDATA[Na2O]]> <![CDATA[TiO2]]> <![CDATA[MnO2]]> <![CDATA[SO3]]> <![CDATA[P2O5]]> other Enriched carbon 49.02 18.30 10.76 10.64 2.05 1.90 0.95 0.90 0.25 2.35 0.08 2.80 Residue 29.02 10.15 23.45 20.65 0.95 0.88 1.96 0.77 0.27 9.35 0.05 2.50

[0135] Table 3 Granulation parameters and profile data of different raw materials

[0136]

[0137] MT / T748-2007 "Method for determination of cold pressing strength of industrial coal briquettes"

[0138] MT / T1073-2007 "Method for determination of thermal strength of industrial coal briquettes"

[0139] MT / T924-2017 "Determination Method for Thermal Stability of Industrial Coal Briquettes"

[0140] Gasification of gasification materials:

[0141] 1) Fix the gasified material in the effective temperature area of ​​the tube furnace, and introduce 100ml / min nitrogen to purge the air in the quartz tube;

[0142] 2) Heating and gasification: 100 ml / min nitrogen purge, heat the tube furnace to 1000°C at a heating rate of 15°C / min, then stop nitrogen and switch to CO2 with a CO2 flow rate of 100 ml / min. After staying for 30 minutes, the reaction is completed, stop CO2, switch to 100 ml / min nitrogen purge to cool down, take out the solid residue in the tube furnace after the temperature drops to room temperature, weigh it, and calculate the gasification carbon conversion rate.

[0143] Table 4 Technical index requirements and methods for fixed bed gasification materials

[0144]

[0145] like Figure 1As shown in the figure, the appearance of the gasified slag sorting enriched carbon is a black, odorless, non-adhesive sand-like particle. On the surface, it is composed of a large number of irregular porous matrix and a small number of spherical particles. The various morphologies of the materials are mixed, attached and wrapped with each other, such as Figure 2 As shown, there are a certain number of porous matrices in the microscopic morphology of the enriched carbon, which preliminarily reflects that it has a certain pore structure and thus forms a certain specific surface area.

[0146] As can be seen from Table 3, compared with Example 1, the amount of coal liquefaction residue added to the molding material of Comparative Example 1 increases, and the carbon conversion rate increases during the gasification process. This is because the coal liquefaction residue is rich in iron content, and also contains a certain amount of alkali metal and alkaline earth metal content, which are all conducive to the catalytic gasification reaction of the molding material. The alkali metal partially bonds with the carbon atom to cause the charge migration of the surface carbon skeleton, change the distribution of the electron cloud of the carbon atom, weaken the carbon-carbon bond strength, enhance the carbon-oxygen bond force, and have a stronger reaction active point on the surface. The gasification reaction is easier to carry out, and the elements that can produce obvious catalytic effects include sodium, iron, potassium, and calcium. However, the amount of coal liquefaction residue added is significantly increased, resulting in an increase in ash content, which affects the amount of coal gas produced per unit gasifier cross section per unit time, that is, it affects the gasification intensity; the amount of coal tar added is reduced, the cold pressing strength, hot pressing strength and thermal stability are all reduced, the formability is poor, and the molding material is easy to disperse under high temperature conditions, which is not conducive to the gasification reaction.

[0147] Comparing Example 2 with Comparative Example 2, in Comparative Example 2, the raw material particle size increases, the strength and thermal stability of the molding material decrease, and the gasification carbon conversion rate also decreases. The smaller the raw material particles, the smaller the internal voids of the molding material system, and the higher the cold pressing strength, hot pressing strength and thermal stability of the molding material. Theoretically, the particle size of the material obtained by 100 mesh screening presents a normal distribution, the large particles are evenly embedded in the fine particles, the large particles become the molding material skeleton, the small particles are condensed into granules under the action of the binder, and the whole is attached to the large particles, and the strength of the molding material formed is higher.

[0148] Comparing Example 2 and Comparative Example 3, the enriched carbon or the mixed particles of enriched carbon and coal powder in Example 2 shrink in volume and become dense due to the pressure applied by the molding machine to form a molding material. The molding pressure is the dominant factor in the compression molding. In Comparative Example 3, the molding pressure is too small, and the molding material is loose inside, which is not conducive to improving the strength of the molding material. The molding pressure has a significant impact on the strength performance of the product.

[0149] Comparing Example 1 and Comparative Example 4, the appropriate moisture in Example 1 is conducive to improving the strength of the gasified slag enriched carbon molding material. This is because the moisture plays a lubricating role in the molding process, reducing the friction inside the molding system, which is conducive to improving the strength of the molding material. Excessive moisture in Comparative Example 4 will affect the contact between the raw material particles, but reduce the strength of the molding material. In addition, if the molding moisture is too high, the molding material will be unable to be demolded and will stick to the ball socket; too high moisture will prolong the molding material air drying time and reduce production efficiency.

[0150] Comparing Example 1 and Comparative Example 5, the coal liquefaction residue extract in Example 1 is obtained at a centrifugal speed of 4000 rpm. At this time, the coal liquefaction residue extract contains 15% asphaltene, 10% heavy oil, 30% ash, and the rest is coke powder and unreacted coal powder, and the component ratio is appropriate; while in Comparative Example 5, the centrifugal speed is reduced to 500 rpm, which is bound to cause the coal liquefaction residue extract to entrain a large amount of washing oil extractant, reduce the bonding properties of the coal liquefaction residue extract, and ultimately lead to a decrease in the strength and thermal stability of the molding material.

[0151] Comparing Example 1 and Comparative Example 6, since the enriched carbon has low volatile matter and poor activation reaction performance after being subjected to high temperature in the gasifier, the gasification slag enriched carbon in Comparative Example 6 is not subjected to oxidation pretreatment and is directly prepared into a molding material, and the carbon conversion rate of the molding material during the gasification process decreases significantly. This is because the gasification slag enriched carbon is selectively oxidized by high temperature air under suitable oxidation conditions to generate more oxygen-containing functional groups, which is beneficial to improving the active sites of the enriched carbon and promoting the gasification reaction.

[0152] Comparing Example 1 and Comparative Example 7, in Comparative Example 7, no coal liquefaction residue extract was added, and the gasification carbon conversion rate was reduced. This is because the coal liquefaction residue extract is rich in iron content and also contains a certain amount of alkali metal and alkaline earth metal content, which are all conducive to the gasification reaction of the catalytic material. The alkali metal partially bonds with the carbon atom to cause the charge migration of the surface carbon skeleton, change the distribution of the carbon atom electron cloud, weaken the carbon-carbon bond strength, enhance the carbon-oxygen bond force, and have a stronger reaction active point on the surface, making the gasification reaction easier to carry out.

[0153] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0154] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A gasification profile, characterized in that: include: The enriched carbon and the binder are oxidatively pretreated. The enriched carbon is an organic carbon residue enrichment obtained by separation technology of coal gasification slag. The binder includes coal liquefaction residue extract and coal tar.

2. The gasification profile according to claim 1, characterized in that: The mass ratio of the oxidatively pretreated enriched carbon, the coal liquefaction residue extract and the coal tar is 100:10-20:5-10.

3. The gasification profile according to claim 1, characterized in that: The ash content of the enriched carbon is ≤15%; and / or, the particle size of the oxidatively pretreated enriched carbon is ≤0.154 mm; And / or, the separation technology includes at least one of flotation, gravity separation, electrostatic separation, and combustion; And / or, the temperature of the oxidation pretreatment is 260-350°C; And / or, the oxidation pretreatment time is 3 to 16 hours.

4. The gasification profile according to claim 1, characterized in that: The coal liquefaction residue extract comprises, by mass, asphaltene: 5-25%; heavy oil: 10-20%; ash: 20-35%; the rest is coke powder and / or coal powder; And / or, the coal liquefaction residue extract comprises metal elements, and the metal elements comprise at least one of iron, alkali metals and alkaline earth metals; and the mass percentage of the metal elements in the coal liquefaction residue extract is 1-10%.

5. The gasification profile according to claim 1, characterized in that: This also includes coal.

6. The gasification profile according to claim 5, characterized in that: The mass ratio of the oxidatively pretreated enriched carbon to coal is 100:5-15; and / or, the coal comprises at least one of lignite or long flame coal; and / or, the ash content of the coal is ≤10%; and / or, the sulfur content of the coal is <1%; And / or, the particle size of the coal is ≤0.154 mm.

7. The gasification profile according to claim 1, characterized in that: The binder also includes other binders other than coal liquefaction residue extract and coal tar; the other binders include at least one of organic binders, inorganic binders or composite binders; the mass ratio of the other binders to the coal liquefaction residue extract is 5 to 35:

100.

8. The gasification profile according to claim 1, characterized in that: The particle size of the gasified material is 5 to 50 mm; And / or, the cold pressing strength of the gasified profile is not less than 380N / piece; And / or, the hot pressing strength of the gasified profile is not less than 230N / piece; And / or, the thermal stability TS of the gasified material +13 >50%; And / or, the gasification carbon conversion rate of the gasification profile is not less than 96%.

9. A method for preparing a gasified profile according to any one of claims 1 to 8, characterized in that: The following steps are involved: (1) subjecting the enriched carbon to oxidation pretreatment to obtain oxidatively pretreated enriched carbon; (2) The oxidatively pretreated enriched carbon is mixed with water, then mixed with a binder, and extruded to obtain a gasification profile.

10. The method for preparing the gasified profile according to claim 9, characterized in that: In the step (1), the temperature of the oxidation pretreatment is 260-350°C; And / or, in step (1), the oxidation pretreatment time is 3 to 16 hours; And / or, in the step (2), the mass ratio of the oxidatively pretreated enriched carbon to water is 100:5-10; And / or, the step (2) further comprises coal, mixing the oxidatively pretreated enriched carbon, coal and water; the mass ratio of the oxidatively pretreated enriched carbon and coal to water is 100:5-10; And / or, in step (2), the temperature of mixing with water is 80-90°C; And / or, in step (2), the temperature of mixing with the binder is 120-180°C; And / or, in the step (2), the coal liquefaction residue extract in the binder is obtained by extracting and centrifuging the coal liquefaction residue; the centrifuge speed is 3000-5000 rpm; the centrifuge temperature is 100-180°C; And / or, in step (2), the extrusion molding pressure is 16 to 22 MPa; And / or, in step (2), the moisture content of the gasified material is less than 5%.

11. Use of the gasified material according to any one of claims 1 to 8 or the gasified material prepared by the preparation method according to claim 9 or 10, characterized in that: The gasification profile is used for fixed bed gasification.

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