A high-reactivity and high-strength coke for hydrogen-rich blast furnace and preparation method thereof

Abstract

The present invention relates to the field of high-reactivity and high-strength coke preparation, and in particular to a high-reactivity and high-strength coke for hydrogen-rich blast furnaces and a preparation method thereof. The preparation method comprises mixing formed coal with coking blended coal and then coking the coke. The preparation method of the present invention is simple to operate and suitable for large-scale production. The prepared high-reactivity and high-strength coke for hydrogen-rich blast furnaces comprises high-reactivity coke obtained by carbonizing formed coal and high-strength coke obtained by carbonizing blended coal bulk materials. The two are combined together by the colloid formed during the coking of the coal materials, and both high reactivity and high strength can be taken into account at the same time.

Description

Technical Field

[0001] The present invention relates to the field of high-reactivity and high-strength coke preparation, and in particular to high-reactivity and high-strength coke for hydrogen-rich blast furnace and a preparation method thereof. Background Art

[0002] Since traditional blast furnaces have high carbon emissions, in order to achieve the goal of carbon reduction, an operating method for hydrogen-rich blast furnaces has been proposed, using hydrogen as a reducing agent to replace part of the coke in the blast furnace to achieve the purpose of reducing carbon emissions. When hydrogen is used as a reducing agent in a blast furnace, the coke ratio will be lower than that of a traditional blast furnace, but the coke also has to play the role of a material column skeleton to ensure that the reducing gas can flow smoothly. In addition, hydrogen participates in the reduction reaction, which increases the amount of heat absorbed and reduces the temperature in the furnace. The rate at which the coke gasification reaction produces CO decreases as the temperature decreases. Therefore, the injection of coke oven gas must increase the reactivity of the coke. Therefore, the research on high-strength and high-reactivity coke plays an important supporting role in the research on hydrogen reduction ironmaking technology. Compared with ordinary coke, highly reactive coke has higher thermal reactivity and its strength can meet the production of hydrogen-rich blast furnaces. It has the characteristics of low initial reaction temperature and fast reaction rate.

[0003] A lot of research has been done on the preparation of high-reactivity and high-strength coke at home and abroad. Japan's research and production of high-strength and high-reactivity coke is generally achieved by adding catalysts, such as calcium-based, magnesium-based and iron-based catalysts. The high strength is generally adjusted by adding strong binders HPC.

[0004] Chinese patent CN113563913A uses long flame coal and dry distilled long flame coal and bituminous coal as raw materials, coal tar as binder, and then die-casts them into blocks. After dry distillation, high-reactivity and high-strength coke is obtained. This method can reduce production costs by adding long flame coal, but the molding pressure is high and industrialization is difficult to achieve.

[0005] Chinese patent CN1264952C prepares high-reactivity and high-strength coke by adjusting the proportion of coking coal with different adhesiveness and reflectivity in the blended coal. Although the reactivity is improved, the negative correlation between the reactivity of coke and the strength after the reaction is not changed.

[0006] Chinese patent CN102719264B prepares highly reactive coke by first preparing coal cores, then spraying asphalt, and finally bonding and mixing with loose coal. The quality of the coke is improved after the reaction compared with the traditional coke with the same raw material ratio, but the process is relatively complicated.

[0007] Chinese patent CN103468287B prepares highly reactive coke by combining iron ore powder with coking coal. However, while the reactivity of such coke is improved, its strength decreases significantly after the reaction. Summary of the invention

[0008] Existing technical means cannot solve the essence of the negative correlation between coke reactivity and post-reaction strength. Even if a solution is occasionally found, large-scale production cannot be achieved due to its complex process.

[0009] The technical problem to be solved by the present invention is: to provide a method for preparing high-reactivity and high-strength coke for hydrogen-rich blast furnaces, and to prepare high-reactivity and high-strength coke for hydrogen-rich blast furnaces by utilizing the existing mature coking process of matching coal.

[0010] In view of the shortcomings of the prior art, one of the objects of the present invention is to provide a method for preparing high-reactivity and high-strength coke for hydrogen-rich blast furnaces; a second object of the present invention is to provide high-reactivity and high-strength coke for hydrogen-rich blast furnaces prepared by the above preparation method.

[0011] The technical solution of the present invention:

[0012] The present invention provides a method for preparing high-reactivity and high-strength coke for hydrogen-rich blast furnaces, which comprises mixing briquette coal with coking blend coal and then coking to obtain the briquette coal; wherein the briquette coal is obtained by raw materials including long flame coal, coking coal and a binder, and the coking coal is selected from one or more of gas coal, 1 / 3 coking coal and lean coal.

[0013] Preferably, in terms of weight percentage, the long flame coal is 10-30%, and the binder is 5-10%; preferably, the long flame coal is 26-30%, and the binder is 8-10%.

[0014] Preferably, the coking coal is 60-85% by weight; preferably, the coking coal is 60-74% by weight.

[0015] Preferably, the coking blend coal contains 60-80% of strong caking coal by weight, and the strong caking coal is fat coal and / or coking coal; preferably, the coking blend coal contains 65-80% of strong caking coal.

[0016] Preferably, in terms of weight percentage, the molding coal accounts for 10-30% and the coking blend coal accounts for 70-90%; preferably, the molding coal accounts for 25-30% and the coking blend coal accounts for 70-75%.

[0017] Preferably, the apparent density of the coal molding on a dry basis is 1.0 to 1.2 t / m; preferably, the equivalent diameter of the coal molding is 5 to 50 mm.

[0018] Preferably, the fineness of the long flame coal is 80% to 90% by weight; preferably, the ash content of the long flame coal is 5 to 10%; more preferably, the volatile content of the long flame coal is 37 to 45%.

[0019] Preferably, the binder is selected from one or more of water, coal tar and asphalt.

[0020] Preferably, the fineness of the coking blend coal is 66-88%; preferably, the moisture content of the coking blend coal is 10-12%.

[0021] The present invention also provides high-reactivity and high-strength coke for hydrogen-rich blast furnace prepared by the above preparation method.

[0022] Preferably, the reactivity CRI of the high-reactivity and high-strength coke for hydrogen-rich blast furnace is 30% to 50%, preferably 40 to 45%, and the post-reaction strength CSR is 60% to 70%; preferably, the cold strength M of the high-reactivity and high-strength coke for hydrogen-rich blast furnace is 100% to 150%. 40 82% to 89%, cold strength M 10 It is 5% to 9%.

[0023] Preferably, the high-reactivity and high-strength coke for the hydrogen-rich blast furnace includes high-reactivity coke and high-strength coke, and the high-reactivity coke and high-strength coke are combined through the colloid formed on their surfaces during the coal coking process; preferably, in terms of weight percentage, the weight proportion of the high-reactivity coke is 10-30%, and the weight proportion of the high-strength coke is 70-90%.

[0024] Preferably, the reactivity CRI of the high-reactivity coke is 65-80%; preferably, the coke strength after reaction SCR of the high-strength coke is 70-75%.

[0025] Beneficial effects of the present invention:

[0026] The invention adopts formed coal and controls the ratio of formed coal and blended coal to obtain a high-reactivity and high-strength coke for hydrogen-rich blast furnace, which is composed of high-reactivity coke and high-strength coke, wherein the formed coal is carbonized to obtain high-reactivity coke, and the blended coal loose coal is carbonized to obtain high-strength coke, and the two are combined together through the colloid formed on the surface during the coking process of the coal material, which can take into account high reactivity and high strength at the same time. At the same time, the preparation method of the invention is simple to operate, low in cost, and suitable for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The figure is a schematic flow chart of the method for preparing high-reactivity and high-strength coke for hydrogen-rich blast furnace of the present invention;

[0028] Figure 2 This is a schematic structural diagram of the high-reactivity and high-strength coke for hydrogen-rich blast furnaces of the present invention;

[0029] The markings in the figure are as follows: 1-high reactivity coke; 2-high strength coke. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and technical effect of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention is described clearly and completely. The embodiments described below are part of the embodiments of the present invention, not all of them. In combination with the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the present invention, "reactivity of coke" refers to the ability of coke to react with carbon dioxide, oxygen and water vapor. Since the reaction of coke with oxygen and water vapor has a similar law to the reaction of carbon dioxide, the present invention uses the reaction between coke and carbon dioxide to evaluate the reactivity of coke in accordance with GB / T 4000-2017 (Test method for coke reactivity and post-reaction strength), that is, a certain mass of coke sample is weighed, placed in a reactor, and reacted with carbon dioxide at 1100°C for 2 hours, and the coke reactivity (Coke Reactivity Index, abbreviated as CRI) is expressed as the percentage of coke mass loss.

[0032] In the present invention, "coke strength after reaction" refers to the ability of coke after reaction to resist fragmentation and wear under mechanical force and thermal stress. The present invention evaluates the coke strength after reaction according to the method in GB / T 4000-2017 (Test method for coke reactivity and strength after reaction), that is, the coke after reaction, after the type I drum test, is expressed as the percentage of the mass of coke with a particle size greater than 10 mm to the mass of the coke after reaction (Coke Strength After Reaction, abbreviated as CSR).

[0033] In the present invention, "cold strength" refers to the strength of coke at room temperature, cold strength M40 refers to the crushing strength of coke at room temperature, and cold strength M10 is the wear resistance of coke at room temperature. The present invention evaluates the cold strength according to the crushing strength (M40) and wear resistance (M10) in GB / T 2006-2008 (Determination method of mechanical strength of coke). M40 refers to the mass percentage of coke larger than 40 mm after the drum test to the mass percentage of coke entering the drum; M10 refers to the mass percentage of coke smaller than 10 mm after the drum test to the mass percentage of coke entering the drum.

[0034] In a specific embodiment of the present invention, the present invention provides a method for preparing high-reactivity and high-strength coke for hydrogen-rich blast furnace, comprising mixing briquette coal with coking blend coal and then coking to obtain the coke;

[0035] The formed coal is prepared from raw materials including long flame coal, coking coal and a binder, wherein the coking coal is selected from one or more of gas coal, 1 / 3 coking coal and lean coal.

[0036] In a preferred embodiment of the present invention, by weight percentage, the long flame coal is 10-30%, and the binder is 5-10%; preferably, the long flame coal is 26-30%, and the binder is 8-10%.

[0037] In another preferred embodiment of the present invention, the coking coal is 60-85% by weight; preferably, the coking coal is 60-74% by weight.

[0038] The coking coal referred to in the present invention refers to a general term for single or several types of coking coal that can be used for conventional coal blending coking production, for example, it can be one or more of gas coal, 1 / 3 coking coal and lean coal.

[0039] The coking blended coal referred to in the present invention refers to a mixture of different single types of coal in a certain proportion and with additives added as needed, for example, a mixture of two or more of gas coal, 1 / 3 coking coal, fat coal, coking coal and lean coal.

[0040] In terms of weight percentage, the coking blend coal contains 60-80% of strong caking coal, preferably 65-80%; the strong caking coal referred to in the present invention refers to fat coal and / or coking coal.

[0041] In terms of weight percentage, the molding coal accounts for 10-30%, and the coking blend coal accounts for 70-90%; preferably, the molding coal accounts for 25-30%, and the coking blend coal accounts for 70-75%.

[0042] In another preferred embodiment of the present invention, the above preparation method adopts a method of coking with profiled coal, comprising the following steps:

[0043] 1) Mix any one or more of gas coal, 1 / 3 coking coal and lean coal in coking coal with long flame coal and binder, and make briquette coal by double roller pelletizing machine. The apparent density of briquette coal on dry basis is 1.0t / m3-1.2t / m3, and the equivalent diameter is 5mm-50mm;

[0044] 2) The above-mentioned briquette coal and the coking coal bulk material are mixed evenly and then sent to the top-loading coke oven for coking;

[0045] 3) The mature coke is quenched to obtain high-reactivity and high-strength coke for hydrogen-rich blast furnaces.

[0046] The present invention also provides high-reactivity and high-strength coke for hydrogen-rich blast furnace prepared by the above preparation method.

[0047] The reactivity CRI of the high-reactivity and high-strength coke for hydrogen-rich blast furnace is 30% to 50%, preferably 40 to 45%, and the post-reaction strength CSR is 60% to 70%; preferably, the cold strength M of the high-reactivity and high-strength coke for hydrogen-rich blast furnace is 40 82% to 89%, cold strength M 10 It is 5% to 9%.

[0048] The high-reactivity and high-strength coke for hydrogen-rich blast furnaces comprises high-reactivity coke and high-strength coke, wherein the colloid on the surface of the high-reactivity coke and the colloid on the surface of the high-strength coke are weakly permeable and adhered to each other; preferably, by weight percentage, the weight proportion of the high-reactivity coke is 10-30%, and the weight proportion of the high-strength coke is 70-90%. The coke reactivity CRI of the high-reactivity coke is 65-80%, and the coke post-reaction strength SCR of the high-strength coke is 70-75%.

[0049] The high-reactivity and high-strength coke for hydrogen-rich blast furnace and the preparation method thereof are described in detail below through specific examples. In the examples, all raw reagent materials are commercially available, and the experimental methods without specific conditions are conventional methods and conventional conditions well known in the art, or according to the conditions recommended by the instrument manufacturer.

[0050] The specific names of the coking coal used are: Jiangchang gas coal, Dongshan 1 / 3 coking coal, Gengyang coking coal, Hongyang lean coal, Heishan long flame coal, Longhu fat coal. Each type of coal conforms to the definition of coking coal classification in the national standard GB / T 5751-2009.

[0051] The 40kg test coke oven (top-mounted) is homemade and complies with the current industry standard "Technical Specifications for Small Coke Ovens for Coking Tests".

[0052] The schematic flow diagram of the method for preparing coke in the embodiment is as follows Figure 1 As shown, Figure 1 The preparation method of the coke is shown to firstly shape one or more of long flame coal and gas coal, 1 / 3 coking coal and lean coal into shaped coal, and then blend it with coking coal bulk coal to obtain high-reactivity and high-strength coke for hydrogen-rich blast furnaces through coking.

[0053] Example 1

[0054] 40kg of the mixture was mixed with 24wt% of gas coal, 34wt% of 1 / 3 coking coal, 8wt% of lean coal, 26wt% of long flame coal and 8wt% of coal tar by a mixer, and then formed into briquette coal by a double-roller pelletizing machine, wherein the briquette coal had an equivalent diameter of 25mm. The ash content of the long flame coal was 5wt% and the volatile content was 40wt%; the coal tar came from the residual ammonia water storage tank of the metallurgical coking plant.

[0055] 40kg of a mixture of coking coal and loose coal is prepared by mixing gas coal 8wt%, 1 / 3 coking coal 14wt%, fat coal 30wt%, coking coal 40wt% and lean coal 8wt% in a mixer, and then 10kg of molded coal and 30kg of the coking coal and loose coal mixture are weighed respectively, mixed evenly and sent into a 40kg test coke oven for coking. The coking conditions are coal loading at 800℃ on the furnace wall, and the final coking temperature is 950℃ at the center of the coke cake, which is maintained for 1h to obtain high-reactivity and high-strength coke for hydrogen-rich blast furnaces, wherein the bulk density of the loose coal is 0.75, the fineness is 75%, and the moisture is 10%.

[0056] The coke reactivity and post-reaction strength test method of GB / T 4000-2017 was used to measure the coke reactivity CRI of the high-reactivity and high-strength coke for hydrogen-rich blast furnace prepared in Example 1 to be 42.6%, and the coke post-reaction strength CSR to be 63.3%;

[0057] The cold strength M40 of the high-reactive and high-strength coke for hydrogen-rich blast furnace prepared in Example 1 was measured to be 84.4% and M10 to be 8.3% by the test method of coke mechanical strength in GB / T 2006-2008. The specific method is as follows:

[0058] 1) The sample is manually screened with a 60mm diameter round hole sieve, and the holes are manually punched (i.e. the material on the sieve is manually tried to pass through the sieve holes, and as long as it can pass through the sieve holes in one direction, it is counted as the material under the sieve). During screening, the amount of material put into the sieve each time shall not exceed 15kg, and the sieve shall be screened cleanly, but the coke shall not be broken by excessive force. The material on the sieve (coke larger than 60mm) is weighed as the drum sample and placed in the container to be put into the drum. Each sample is 15kg (weighed to 0.1kg), and at least two samples should be taken for each test.

[0059] 2) Carefully place one of the samples into the cleaned drum, close the drum cover, remove the drum crank, start the drum, stop the drum after 100 revolutions, let it stand for 1-2 minutes to allow the dust to settle, then open the drum cover, pour out the coke in the drum, clean it carefully, and collect the coke powder on the drum cover and inside the drum.

[0060] 3) The coke discharged from the drum is screened with round hole sieves with diameters of 40 mm and 10 mm in turn. The part larger than 40 mm must be punched by hand.

[0061] 4) When screening, we must strive to screen out the coke cleanly, but also avoid using excessive force to cause the coke to be hit and broken.

[0062] 5) Weigh the mass of coke of each particle size greater than 40mm, 40-10mm and less than 10mm respectively (accurate to 0.1kg). The difference between the sum and the mass of coke entering the drum is the loss. When the loss is not less than 0.3kg, the test is invalid. When it is less than 0.3kg, it is counted as the grade less than 10mm.

[0063] 6) Calculation of results

[0064] The crushing strength M40 is calculated according to formula (1):

[0065] M40=m1 / m*100%

[0066] The wear resistance M10 is calculated according to formula (2):

[0067] M10=m2 / m*100%

[0068] Where:

[0069] m——the mass of coke entering the drum, in kilograms (kg);

[0070] m1——the mass of coke larger than 40mm after exiting the drum, in kilograms (kg);

[0071] m2——The mass of coke less than 10mm after exiting the drum, in kilograms (kg);

[0072] The test results are rounded to one decimal place.

[0073] The high-reactivity and high-strength coke for hydrogen-rich blast furnace prepared in Example 1 was placed in a coke drop strength testing machine and dropped twice. High-reactivity coke and high-strength coke were obtained, and then the GB / T4000-2017 coke reactivity and post-reaction strength test method was used to measure the coke reactivity CRI of the high-reactivity coke to be 66.4%, and the coke post-reaction strength to be 18.1%; the coke reactivity CRI of the high-strength coke was 17.4%, and the coke post-reaction strength SCR was 73.2%. The weight percentage of high-reactivity coke to high-reactivity and high-strength coke for hydrogen-rich blast furnace was 37.5%, and the weight percentage of high-strength coke to high-reactivity and high-strength coke for hydrogen-rich blast furnace was 62.5%.

[0074] Example 2

[0075] 40kg of the mixture was mixed with 20wt% gas coal, 30wt% 1 / 3 coking coal, 10wt% lean coal, 30wt% long flame coal and 10wt% asphalt in a mixer, and then formed into briquette coal by a double-roller pelletizing machine, wherein the briquette coal had an equivalent diameter of 25mm. The ash content of the long flame coal was 5%, and the volatile content was 40%; the asphalt came from the coal tar workshop of the coking plant.

[0076] 40kg of a mixture of coking coal and loose coal is prepared by mixing gas coal 10wt%, 1 / 3 coking coal 10wt%, fat coal 40wt% and coking coal 40wt% in a mixer, and then 12kg of formed coal and 28kg of the coking coal and loose coal mixture are weighed and mixed evenly and sent into a 40kg test coke oven for coking. The coking conditions are coal loading at 800℃ on the furnace wall and the final coking temperature is 950℃ at the center of the coke cake, which is maintained for 1h to obtain high-reactivity and high-strength coke for hydrogen-rich blast furnaces, wherein the bulk density of the loose coal is 0.75, the fineness is 78%, and the moisture is 10%.

[0077] The method described in Example 1 was used to measure the coke reactivity CRI of the high-reactivity and high-strength coke for hydrogen-rich blast furnace prepared in Example 2 to be 45.3%, the coke post-reaction strength CSR to be 68.3%, the cold strength M40 to be 85.4%, and the cold strength M10 to be 8.9%.

[0078] The method described in Example 1 was adopted to measure that the coke reactivity CRI of the high-reactivity and high-strength coke for hydrogen-rich blast furnace prepared in Example 2 was 70.3%, and the strength after coke reaction was 15.5%; the coke reactivity CRI of the high-strength coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace was 16.9%, and the strength SCR after coke reaction was 74.4%, the weight percentage of high-reactivity coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace was 28.5%, and the weight percentage of high-strength coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace was 71.5%.

[0079] Example 3

[0080] 40kg of the mixture is mixed with 30wt% gas coal, 40wt% 1 / 3 coking coal, 15wt% lean coal, 10wt% long flame coal and 5wt% water in a mixer, and then formed into briquette coal by a roller pelletizing machine, and the briquette coal has an equal diameter of 25mm. The ash content of the long flame coal is 5%, and the volatile content is 40%;

[0081] 40kg of a mixture of 20wt% coking coal, 30wt% fat coal, 40wt% coking coal and 10wt% lean coal is prepared by mixing in a mixer. Then, 4kg of formed coal and 36kg of the mixture of coking coal are weighed respectively, and the mixture is mixed evenly and then sent into a 40kg test coke oven for coking. The coking conditions are coal loading at 800℃ on the furnace wall, and the final coking temperature is 950℃ at the center of the coke cake, which is maintained for 1h to obtain high-reactivity and high-strength coke for hydrogen-rich blast furnaces, wherein the bulk density of the loose coal is 0.75, the fineness is 79%, and the moisture is 10%.

[0082] The method described in Example 1 was used to measure the coke reactivity CRI of the high-reactivity and high-strength coke for hydrogen-rich blast furnace prepared in Example 3 to be 43.5%, the coke post-reaction strength CSR to be 64.2%, the cold strength M40 to be 84.3%, and the M10 to be 8.4%.

[0083] The method described in Example 1 was adopted to measure that the coke reactivity CRI of the high-reactivity coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace prepared in Example 3 was 67.5%, and the strength after reaction was 20.3; the coke reaction CRI of the high-strength coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace was 17.2, and the strength SCR after coke reaction was 73.6%, the weight percentage of high-reactivity coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace was 16.7%, and the weight percentage of high-strength coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace was 83.3%.

[0084] Example 4

[0085] 40kg of the mixture is mixed with 30wt% gas coal, 40wt% 1 / 3 coking coal, 15wt% lean coal, 10wt% long flame coal and 5wt% water in a mixer, and then formed into briquette coal by a roller pelletizing machine, and the briquette coal has an equal diameter of 25mm. The ash content of the long flame coal is 5%, and the volatile content is 40%;

[0086] 40kg of a mixture of coking coal and loose coal is prepared by mixing in a mixer in the proportion of 1 / 3 coking coal (20wt%), fat coal (30wt%), coking coal (40wt%) and lean coal (10wt%). Then, 20kg of formed coal and 20kg of the coking coal and loose coal mixture are weighed respectively, mixed evenly and sent into a 40kg test coke oven for coking. The coking conditions are coal loading at 800℃ on the furnace wall, and the final coking temperature is 950℃ at the center of the coke cake, which is maintained for 1h to obtain high-reactivity and high-strength coke for hydrogen-rich blast furnaces, wherein the bulk density of the loose coal is 0.75, the fineness is 79%, and the moisture is 10%.

[0087] The coke reactivity CRI of the high-reactivity and high-strength coke for hydrogen-rich blast furnace obtained in Example 3 was measured by the method described in Example 1 to be 63.5%, the coke post-reaction strength CSR to be 44.2%, the cold strength M40 to be 54.3%, and the M10 to be 28.4%.

[0088] The method described in Example 1 was adopted to measure that the coke reactivity CRI of the high-reactivity coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace prepared in Example 3 was 67.5%, and the strength after coke reaction was 20.3; the coke reaction CRI of the high-strength coke was 17.2, and the strength SCR after coke reaction was 73.6%; the weight percentage of high-reactivity coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace was 47.3% of the high-reactivity and high-strength coke for hydrogen-rich blast furnace, and the weight percentage of high-strength coke in the high-reactivity and high-strength coke for hydrogen-rich blast furnace was 52.7%.

[0089] Comparative Example 1

[0090] The difference from Example 1 is that the coal molding process is not used, but the various types of coal are directly mixed for coking. The same coal types and weight percentages as those in Example 1 are used, and the proportion is: 12wt% gas coal, 19wt% 1 / 3 coking coal, 22.5wt% fat coal, 30wt% coking coal, 8wt% lean coal, 6.5wt% long flame coal and 2wt% coal tar.

[0091] According to the above proportions, each type of coal is weighed to obtain 40 kg of a mixture, which is evenly mixed with a mixer and then sent into a 40 kg test coke oven for coking. The coking conditions are coal loading at the furnace wall at 800°C, and the final coking temperature is that the center temperature of the coke cake reaches 950°C and is maintained for 1 hour to obtain the coke of Comparative Example 1.

[0092] The coke reactivity CRI, measured by the method described in Example 1, was 36.5%, the coke post-reaction strength CSR was 43.2%, the cold strength M40 was 72.4%, and the cold strength M10 was 15.3%.

[0093] Comparative Example 2

[0094] The difference from Example 2 is that the coal molding process is not used, but the coal types are directly mixed for coking. The same coal types and weight percentages as those in Example 2 are used, and the proportion is: 13wt% gas coal, 16wt% 1 / 3 coking coal, 28wt% fat coal, 28wt% coking coal, 3wt% lean coal, 9wt% long flame coal and 3wt% coal tar.

[0095] Weigh each type of coal according to the above proportion to obtain 40kg of a mixture, mix it evenly with a mixer and then send it into a 40kg test coke oven for coking. The coking conditions are coal loading at the furnace wall at 800°C, and the final coking temperature is that the center temperature of the coke cake reaches 950°C and is maintained for 1 hour to obtain comparative example 2 coke.

[0096] The coke reactivity CRI was measured by the method described in Example 1 to be 38.5%, the coke strength after reaction CSR was 41.2%, the cold strength M40 was 71.4%, and the cold strength M10 was 15.1%.

[0097] Comparative Example 3

[0098] The difference from Example 3 is that the coal molding process is not used, but the coal types are directly mixed for coking. The same coal types and weight percentages as those in Example 3 are used, and the proportion is: 3wt% gas coal, 22wt% 1 / 3 coking coal, 27wt% fat coal, 36wt% coking coal, 10.5wt% lean coal, 1.0wt% long flame coal and 0.5% water.

[0099] According to the above proportions, each type of coal is weighed to obtain 40 kg of a mixture, which is evenly mixed with a mixer and then sent into a 40 kg test coke oven for coking. The coking conditions are coal loading at the furnace wall at 800°C, and the final coking temperature is that the center temperature of the coke cake reaches 950°C and is maintained for 1 hour to obtain comparative example 3 coke.

[0100] The coke reactivity CRI measured by the method described in Example 1 was 28.5%, the coke post-reaction strength CSR was 60.2%, the cold strength M40 was 83.4%, and the cold strength M10 was 8.1%.

[0101] The coke reactivity of the high-reactivity and high-strength coke for hydrogen-rich blast furnaces prepared in Examples 1-4 of the present invention is 42.6-63.5%, and the strength after the coke reaction is 44.2-68.3%, which can take into account both high reactivity and high strength. Compared with Comparative Examples 1-3, the high-reactivity and high-strength coke for hydrogen-rich blast furnaces prepared in Examples 1-3 of the present invention has a coke reactivity increased by 16.7-52.6%, and the strength after the coke reaction is increased by 6.6-65.8%.

[0102] In summary, the present invention adopts shaped coal and controls the ratio of shaped coal and blended coal to produce a high-reactivity and high-strength coke for hydrogen-rich blast furnace, which includes high-reactivity coke and high-strength coke, wherein the shaped coal is carbonized to produce high-reactivity coke, and the blended coal loose coal is carbonized to produce high-strength coke, and the two are combined together by the colloid formed on the surface of the coal during the coking process, such as Figure 2 As shown in Figure 1, high reactivity and high strength can be achieved at the same time. In addition, the highly reactive coke formed by coal molding preferentially reacts with CO 2 The high-strength coke formed by protecting the loose coal material reacts with water vapor, so that the comprehensive reactivity and post-reaction strength of the coke are improved compared with conventional coke, which can make the hydrogen-rich blast furnace run smoothly, improve the utilization rate of coal gas, and achieve the purpose of carbon reduction. The preparation method of the invention is simple to operate, low in cost, and suitable for large-scale production.

[0103] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing hydrogen-rich blast furnace coke, characterized in that: The method comprises mixing briquette coal and coking blend coal and then coking the mixture; in terms of weight percentage, the briquette coal accounts for 10-30% and the coking blend coal accounts for 70-90%; The briquette is prepared from raw materials including long flame coal, coking coal and a binder, wherein the coking coal is gas coal, 1 / 3 coking coal and lean coal; by weight percentage, the long flame coal is 10-30%, the binder is 5-10% and the coking coal is 60-85%; The coking blend coal contains 60-80% of strong caking coal, the strong caking coal is fat coal and coking coal, and the coking blend coal also includes one or more of gas coal, 1 / 3 coking coal and lean coal; The coke reactivity CRI of the hydrogen-rich blast furnace coke is 40%-50%, and the coke strength after reaction CSR is 60%-70%; The cold strength M40 of the hydrogen-rich blast furnace coke is 82% to 89%, and the cold strength M10 is 5% to 9%.

2. The preparation method according to claim 1, characterized in that: The long flame coal is 26-30%, and the binder is 8-10%.

3. The preparation method according to claim 1, characterized in that: The coking coal is 60-74%.

4. The preparation method according to claim 1, characterized in that: The coking blend coal contains 65-80% of strong caking coal.

5. The preparation method according to claim 1, characterized in that: The molding coal is 25-30%, and the coking blend coal is 70-75%.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The apparent density of the briquette coal on a dry basis is 1.0 to 1.2 t / m 3 .

7. The preparation method according to claim 6, characterized in that: The equivalent diameter of the coal formation is 5 mm to 50 mm.

8. The preparation method according to any one of claims 1 to 5, characterized in that: Calculated by weight percentage, the fineness of the long flame coal is 80% to 90%.

9. The preparation method according to claim 8, characterized in that: The ash content of the long flame coal is 5-10%.

10. The preparation method according to claim 8, characterized in that: The volatile matter content of the long flame coal is 37-45%.

11. The preparation method according to claim 6, characterized in that: Calculated by weight percentage, the fineness of the long flame coal is 80% to 90%.

12. The preparation method according to any one of claims 1 to 5, characterized in that: The binder is selected from one or more of water, coal tar and asphalt.

13. The preparation method according to claim 6, characterized in that: The binder is selected from one or more of water, coal tar and asphalt.

14. The preparation method according to claim 8, characterized in that: The binder is selected from one or more of water, coal tar and asphalt.

15. The preparation method according to any one of claims 1 to 5, characterized in that: The coking blend coal has a fineness of 66-88%.

16. The preparation method according to claim 15, characterized in that: The moisture content of the coking blend coal is 10-12%.

17. The preparation method according to claim 6, characterized in that: The coking blend coal has a fineness of 66-88%.

18. The preparation method according to claim 8, characterized in that: The coking blend coal has a fineness of 66-88%.

19. The preparation method according to claim 12, characterized in that: The coking blend coal has a fineness of 66-88%.

20. A hydrogen-rich blast furnace coke, characterized in that: The hydrogen-rich blast furnace coke is prepared by the preparation method according to any one of claims 1 to 19.

21. The hydrogen-rich blast furnace coke according to claim 20, characterized in that: The coke reactivity CRI of the hydrogen-rich blast furnace coke is 40-45%.

22. The hydrogen-rich blast furnace coke according to claim 20 or 21, characterized in that: The hydrogen-rich blast furnace coke includes high-reactivity coke and high-strength coke.

23. The hydrogen-rich blast furnace coke according to claim 22, characterized in that: In terms of weight percentage, the weight percentage of the high-reactivity coke is 10-30%, and the weight percentage of the high-strength coke is 70-90%.

24. The hydrogen-rich blast furnace coke according to claim 23, characterized in that: The coke reactivity CRI of the high-reactivity coke is 65-80%.

25. The hydrogen-rich blast furnace coke according to claim 23, characterized in that: The high-strength coke has a coke strength after reaction (CSR) of 70-75%.

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