Method for producing foundry coke on large-scale coke oven by completely using briquette coal
By using the method of completely producing cast coke with molded coal on the mainframe coke oven, the problems of uneven coke particle size and insufficient production capacity are solved, the coke uniformity and high yield rate are achieved, resources and electricity are saved, and it is more environmentally friendly and economical.
Patent Information
- Application Number
- CN202510105344.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-23
- Publication Date
- 2025-05-02
AI Technical Summary
In the prior art, the coke particle size is uneven, the production capacity is difficult to meet the needs of large-scale commercialization, and resources and electricity are wasted.
The method of producing cast coke on a main machine coke oven is adopted, including crushing and mixing the raw coal with liquid agent in proportion to form a primary material, and then forming standard columnar coal in die-casting, drying and carbonizing until mature, and obtaining cast coke with uniform particle size and shape.
The uniformity of coke particle size is achieved, the yield of cast coke is improved, the yield of coke powder is reduced, the resource and electricity is saved, the demand for large-scale commercial production is met, and it is more environmentally friendly and economical.
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Figure CN119912956A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of coal chemical industry, and in particular to a method for producing foundry coke completely by using shaped coal in a large-scale coke oven. Background Art
[0002] my country is the world's largest manufacturing country and requires a large amount of foundry coke every year. The traditional foundry coke production method is that after the coke is quenched in the coke oven, it is screened and the particles that meet the particle size requirements are used as foundry coke. The larger particles are crushed (commonly known as cutting coke) and then the particles that meet the requirements are used as foundry coke. The rest are used as metallurgical coke or other purposes. The foundry coke yield is less than 50%. When crushed, more coke powder (below 13mm) will be produced, accounting for about 15% of the total coke or even higher. The ash content of coke powder is often higher than that of coke in the same furnace, so it is rarely mixed back into the coking raw coal. Most coking plants generally mix about 5% back. In addition, the coke powder has a high hardness and needs to be ground when mixed back, which causes greater wear and tear on power consumption equipment.
[0003] The above problems can be solved by using only shaped coal for coking. A shaped coal plant in Shanxi uses the technology of using only shaped coal for coking, using about 70% anthracite and about 30% fat coal to produce shaped coke that meets the standards of metallurgical coke. However, due to the use of an internal combustion and internal heat vertical furnace, the particle size of the shaped coke is too small to meet the requirements of foundry coke, and the furnace is small and the output is low. In some places in Henan and Fujian, tunnel kilns are also used to produce foundry coke with only shaped coal. The general output is below 20,000 tons / year, which cannot achieve large-scale commercial production. These plants do not have a complete gas recovery and purification system, and there is direct combustion of raw gas and direct discharge or burning of remaining gas.
[0004] Therefore, it is very necessary to develop a new coking method that has large and uniform coke particle size, a production capacity that meets the needs of large-scale commercialization, saves resources and electricity, and is economical and environmentally friendly. Summary of the invention
[0005] The purpose of the present invention is to solve the problems in the prior art of uneven coke particle size, difficulty in meeting large-scale commercial production needs, and waste of resources and electricity, and to propose a method for producing foundry coke in a large coke oven using only briquette coal.
[0006] In order to achieve the above object, the present invention adopts the following technical solutions:
[0007] A method for producing foundry coke entirely using briquette coal in a large coke oven comprises the following steps:
[0008] Step 1: crushing and mixing the raw coal for making foundry coke and the liquid agent in proportion to obtain a primary material for molding;
[0009] Step 2: Form the first-grade material into a standard columnar coal shape with a central penetration by die-casting;
[0010] Step 3: Dry the briquette using dry mixed gas at standard temperature, so that the pressure resistance of a single briquette is greater than 800N;
[0011] Step 4: According to the standard temperature, the coal briquettes are stacked and sent into the coke oven carbonization chamber for carbonization until maturity to obtain foundry coke.
[0012] Preferably, the liquid in step 1 comprises 0.5-3.0% of organic binder based on the total dry weight of the material and 12-16% of water based on the total dry weight of the material.
[0013] Furthermore, in step one, the raw coal is crushed into a particle size less than 3 mm, of which particles less than 1 mm account for greater than or equal to 70%, and particles 0.5 mm account for greater than or equal to 40%.
[0014] Preferably, the standard coal shape in step 2 includes a cylindrical or prismatic shape with a diameter of 120 mm and a height of 120 mm, wherein the coal shape is formed with a boss structure, the end face of the boss is 30% smaller than the end face of the coal shape, the height is 3-7 mm, and the diameter of the central through hole of the coal shape is greater than or equal to 25 mm.
[0015] Preferably, the die-casting pressure in step 2 is greater than or equal to 20 MPa.
[0016] Preferably, the mixed gas in step three is a mixture of coke oven combustion chamber tail gas and air.
[0017] Furthermore, in step three, the drying moisture content is less than 3%.
[0018] Preferably, the standard temperature in step 3 and step 4 is 80-130°C.
[0019] Preferably, in step 4, the medium-sized coal is stacked in a single layer and sent into the carbonization chamber of the coke oven.
[0020] Furthermore, in step 4, the coke matures when the temperature in the coke oven carbonization chamber reaches 1200°C-1300°C.
[0021] Compared with the prior art, the present invention provides a method for producing foundry coke in a large coke oven using only briquette coal, which has the following beneficial effects:
[0022] 1. Compared with the method of producing foundry coke in a large coke oven using only shaped coal, the product is foundry coke with uniform particle size and shape, and there is no need to crush the coke after quenching, which greatly reduces the yield of coke powder and saves resources. The foundry coke yield is greatly improved, and the problem of difficulty in recycling coke powder is avoided.
[0023] 2. Compared with the existing coking plants using shaped coal, the method of producing foundry coke entirely using shaped coal in large-scale coke ovens has a large output and a low unit cost. It is more environmentally friendly by relying on the well-developed gas recovery and purification system of large-scale coking plants.
[0024] 3. This method of producing foundry coke entirely with briquette in large-scale coke ovens utilizes most of the facilities of existing large-scale coking plants, and only adds mixing, shaping, drying and stacking operations between the crushing and coking operations of the coking plant. There is no need to build new coke ovens, thus avoiding repeated investment.
[0025] 4. The method of producing foundry coke entirely with briquette coal in a large coke oven does not substantially change the heating system of the existing coking plant and is easier to operate.
[0026] The parts not involved in the device are the same as the existing technology or can be implemented by using the existing technology. The foundry coke produced by the present invention is all products with uniform particle size and shape. The coke powder yield of the traditional coke oven is higher than that of the traditional coke oven, and the finished product rate accounts for more than 85% of the total coke, and the coke powder yield does not exceed 10%. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 The coking process flow chart proposed by the present invention;
[0028] Figure 2 It is the process flow chart of coking process of existing ramming coke oven;
[0029] Figure 3 This is the process flow chart of the existing top-loading coke oven coking process. DETAILED DESCRIPTION
[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.
[0031] In addition, reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.
[0032] Embodiment 1:
[0033] Reference Figure 1 A method for producing foundry coke entirely using briquette coal in a large coke oven comprises the following steps:
[0034] Step 1: Utilize the existing large-scale coking plant's coal blending, crushing and coke oven and its complete gas recovery and purification system, add mixing, shaping, drying and stacking devices between the coking plant's crushing and coke oven, mix the raw coal for casting coke according to proportion and crush it to a particle size of less than 3mm, of which less than 1mm accounts for no less than 70% and 0.5mm accounts for no less than 40%; then mix and stir evenly with an organic binder and water, the binder ratio accounts for 0.5-3.0% of the total dry weight of the material, and the moisture content of the material is 12-16%, to obtain a material suitable for extrusion or stamping;
[0035] Step 2: Use an extrusion or stamping machine to process the material in step 1 into a cylindrical coal mold with a diameter of about 120mm and a height of about 120mm or a hexagonal prism (octagonal prism) with a diameter of about 120mm and a height of about 120mm. The molding pressure is not less than 20MPa. To prevent the coke blocks from sticking to each other, there are bosses at both ends of the column with an area of about 5mm and a height of less than 30% of the column end surface. To prevent the coke blocks from having many cracks, a through hole with a diameter of not less than 25mm is processed along the axis at the center of the coal mold during molding. The size of the coal mold can be adjusted according to user needs;
[0036] Step 3: The formed briquette enters the mesh belt or chain plate continuous drying device in a single-layer arrangement using a conveyor belt; the heat source for drying is a mixture of exhaust gas from the coke oven combustion chamber and air, and the temperature of the mixture is controlled at 80-130°C to prevent cracks in the briquette; when the briquette is dried to a moisture content of less than 3%, it is unloaded from the drying device and conveyed to the stacker. At this time, the compressive strength of a single briquette is greater than 800N;
[0037] Step 4: The dried briquette is stacked in the coke oven pusher by a stacker into a briquette stack whose height is not higher than the required coal loading height of the coke oven carbonization chamber and whose width is slightly smaller than the carbonization chamber, and then pushed into the coke oven carbonization chamber by the coal pusher, and then the coke oven carbonization chamber is sealed;
[0038] Step 5: The shaped coal pile is carbonized to maturity in the coke oven carbonization chamber according to the original heating system, and is pushed out of the coke oven by a coke pusher. After quenching, large pieces of foundry coke with uniform particle size and shape can be obtained. The coke pieces do not stick to each other or can be separated by tapping or colliding with each other.
[0039] As mentioned in step 1, the existing large-scale coking plant's coal blending, crushing and coke ovens and their complete gas recovery and purification systems are used to add mixing, shaping, drying and stacking devices between the crushing and coke ovens of the coking plant. This can avoid duplication of construction, make full use of existing facilities, and only add necessary process links and facilities, saving investment.
[0040] The raw coal for refining foundry coke is mixed in proportion and then crushed to a particle size below 3mm, of which particles below 1mm account for no less than 70% and particles 0.5mm account for no less than 40%. This particle size requirement can reduce the mutual adhesion between coke blocks; the organic binder should be water-soluble; the moisture content of the material is 12-16%. Too low moisture content will result in poor plasticity of the material, which may easily cause the inside of the briquette to be loose. Too high moisture content will easily increase the fluidity of the material and cause it to emerge from the gaps in the molding machine.
[0041] The molding pressure described in step 2 is not less than 20MPa. If the pressure is lower than this, the internal part of the briquette will be loose, resulting in a decrease in the drum strength of the produced coke. The bosses at both ends of the column, which are less than 30% of the column end surface and about 5mm high, are the key to preventing the upper and lower layers of coke blocks from sticking to each other.
[0042] It is a water-soluble organic binder, and its added amount depends on the price and performance of the binder. When its added amount is less than 1%, it should be mixed with a small amount of water to form a slurry with a higher concentration before mixing with the raw coal. Depending on the moisture content of the raw coal, an appropriate amount of water should be added to avoid uneven mixing of the dry powder with the coal or excessive moisture content of the mixed raw coal due to excessively dilute concentration.
[0043] The formed briquette is arranged in a single layer by a conveyor belt and enters a mesh belt or chain plate continuous drying device. The heat source for drying is a mixture of exhaust gas from the coke oven combustion chamber and air. The temperature of the mixed gas is controlled at 80-130℃ to prevent cracks in the briquette. When the briquette is dried to a moisture content of less than 3%, it is unloaded from the drying device and conveyed to the stacker. At this time, the compression resistance of a single briquette is greater than 800N. The single-layer arrangement of briquette and drying with a mesh belt or chain plate can minimize the breakage of briquette. When the moisture content of briquette is less than 3%, it can ensure that the briquette has sufficient strength (800N / piece) to meet the requirements of subsequent transportation and stacking.
[0044] The existing large-scale coke oven and its complete gas purification and recovery system are used. The coke oven is a large top-loading coal coke oven or a large ramming coke oven. The top-loading coal coke oven needs to transform the original coke pusher into a coal pusher and coke pusher. The ramming machine of the ramming type coke oven basically only needs to disable its ramming function, and the stacker can borrow (use) the building block stacker.
[0045] The original coke oven heating system is basically unchanged, that is, the coke matures when the temperature in the coke oven carbonization chamber reaches about 1250°C.
[0046] Embodiment 2:
[0047] Reference Figure 1 , producing foundry coke entirely from briquette coal in top-charging coke ovens, including the following:
[0048] (1) Utilize the existing large-scale coking plant's coal blending, crushing and coke ovens as well as their complete gas recovery and purification systems, and add mixing, shaping, drying and stacking devices between the crushing and coke ovens in the coking plant; modify the coke oven pusher and add a stacking box. After the stacking is completed, the stacking box is put into the coke oven carbonization chamber. Then the stacking box cooperates with the coke pusher, and the stacking box is pulled out of the carbonization chamber. The shaped coal stack remains in the carbonization chamber to complete the furnace loading.
[0049] (2) The raw coal for foundry coke making is mixed in proportion and then crushed to a particle size of less than 3 mm, of which particles below 1 mm account for no less than 70% and particles 0.5 mm account for no less than 40%. If the original crusher cannot meet the particle size requirement, a secondary crusher can be added or the crusher can be replaced; the raw coal that meets the particle size requirement after crushing is mixed with an organic binder and water and stirred evenly, with the binder ratio accounting for 0.5-3.0% of the total dry weight of the material and the moisture content of the material being 12-16%, to obtain a material suitable for extrusion or stamping.
[0050] (3) Use an extrusion or stamping machine to process the material in step 1 into a cylindrical coal mold with a diameter of about 120 mm and a height of about 120 mm or a hexagonal prism (octagonal prism) with a diameter of about 120 mm and a height of about 120 mm. The molding pressure is not less than 20 MPa. To prevent the coke blocks from sticking to each other, there are bosses at both ends of the column with an area less than 30% of the column end surface and a height of about 5 mm. To prevent the coke blocks from having many cracks, a through hole with a diameter of not less than 25 mm is processed along the axis at the center of the coal mold during molding. The size of the coal mold can be adjusted according to user needs.
[0051] (4) The formed coal briquettes are arranged in a single layer on a conveyor belt and enter a mesh belt or chain plate continuous drying device; the heat source for drying is a mixture of exhaust gas from the coke oven combustion chamber and air, and the temperature of the mixture is controlled at 80-130°C to prevent cracks in the coal briquettes; when the coal briquettes are dried to a moisture content of less than 3%, they are unloaded from the drying device and conveyed to a stacker. At this time, the compressive strength of a single coal briquettes is greater than 800N to meet the requirements of transportation and stacking.
[0052] (5) The dried coal pieces are stacked by a stacking machine in a newly added stacking box into a coal piece stack whose height is not higher than the required coal loading height of the coke oven carbonization chamber and whose width is slightly smaller than that of the coke oven carbonization chamber. The coal piece stack is sent into the coke oven carbonization chamber, and then the coke oven carbonization chamber is sealed.
[0053] (6) The shaped coal pile is carbonized to maturity in the coke oven carbonization chamber according to the original heating system, and is pushed out of the coke oven by a coke pusher. After quenching, large pieces of foundry coke with uniform particle size and shape can be obtained. The coke pieces do not stick to each other or can be separated by tapping or colliding with each other.
[0054] (7) After quenching, the molded coke is screened to remove a small amount of coke powder to obtain the finished foundry coke. The finished foundry coke is slightly smaller than the briquette due to the shrinkage during the coking process. The coke powder yield does not exceed 10%.
[0055] Embodiment three:
[0056] Reference Figure 1 , using briquette coal for coking in stamping coke ovens, including the following:
[0057] (1) Utilize the existing large-scale coking plant's coal blending, crushing and coke ovens as well as their complete gas recovery and purification systems, and add mixing, shaping, drying and stacking devices between the coking plant's crushing and coke ovens.
[0058] (2) The raw coal for foundry coke making is mixed in proportion and then crushed to a particle size of less than 3 mm, of which particles below 1 mm account for no less than 70% and particles 0.5 mm account for no less than 40%. If the original crusher cannot meet the particle size requirement, a secondary crusher can be added or the crusher can be replaced; the raw coal that meets the particle size requirement after crushing is mixed with an organic binder and water and stirred evenly, with the binder ratio accounting for 0.5-3.0% of the total dry weight of the material and the moisture content of the material being 12-16%, to obtain a material suitable for extrusion or stamping.
[0059] (3) Use an extrusion or stamping machine to process the material in step 1 into a cylindrical coal mold with a diameter of about 120 mm and a height of about 120 mm or a hexagonal prism (octagonal prism) with a diameter of about 120 mm and a height of about 120 mm. The molding pressure is not less than 20 MPa. To prevent the coke blocks from sticking to each other, there are bosses at both ends of the column with an area less than 30% of the column end surface and a height of about 5 mm. To prevent the coke blocks from having many cracks, a through hole with a diameter of not less than 25 mm is processed along the axis at the center of the coal mold during molding. The size of the coal mold can be adjusted according to user needs.
[0060] (4) The formed coal briquettes are arranged in a single layer on a conveyor belt and enter a mesh belt or chain plate continuous drying device; the heat source for drying is a mixture of exhaust gas from the coke oven combustion chamber and air, and the temperature of the mixture is controlled at 80-130°C to prevent cracks in the coal briquettes; when the coal briquettes are dried to a moisture content of less than 3%, they are unloaded from the drying device and conveyed to a stacker. At this time, the compressive strength of a single coal briquettes is greater than 800N to meet the requirements of transportation and stacking.
[0061] (5) The dried coal pieces are stacked into coal piece stacks that match the internal dimensions of the coke oven tamping box by a stacking machine. The coal piece stacks are sent into the coke oven carbonization chamber, and then the coke oven carbonization chamber is sealed.
[0062] (6) The shaped coal pile is carbonized to maturity in the coke oven carbonization chamber according to the original heating system, and is pushed out of the coke oven by a coke pusher. After quenching, large pieces of foundry coke with uniform particle size and shape can be obtained. The coke pieces do not stick to each other or can be separated by tapping or colliding with each other.
[0063] (7) After quenching, the molded coke is screened to remove a small amount of coke powder to obtain the finished foundry coke. The finished foundry coke is slightly smaller than the briquette due to the shrinkage during the coking process. The coke powder yield does not exceed 10%.
[0064] According to Example 2 and Example 3, Table 1 and Table 2 are obtained, which are as follows:
[0065] Table 1 Comparison of the process of the present invention with the process of the conventional top-loading coke oven and ramming coke oven
[0066]
[0067] Table 2 Output comparison of the product of the present invention and traditional top-loading coke oven and ramming coke oven
[0068]
[0069] illustrate:
[0070] ① The ash content of coke from both processes shall not be greater than 12%, which is determined by the raw coal for coking;
[0071] ② The sulfur content of coke from both processes shall not be greater than 0.8%, which is determined by the coking raw coal.
[0072] The above are exemplary embodiments disclosed in the present invention, but it should be noted that various changes and modifications may be made without departing from the scope disclosed in the embodiments of the present invention as defined in the claims. The functions, steps and / or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.
[0073] It should be understood that, as used herein, the singular forms "a", "an" are intended to include the plural forms as well, unless the context clearly supports an exception. It should also be understood that, as used herein, "and / or" refers to any and all possible combinations including one or more of the associated listed items.
[0074] The serial numbers of the embodiments disclosed in the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.
[0075] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.
Claims
1. A method for producing foundry coke entirely using briquette coal in a large coke oven, characterized in that: The steps include: Step 1: crushing and mixing the raw coal for making foundry coke and the liquid agent in proportion to obtain a primary material for molding; Step 2: Form the first-grade material into a standard columnar coal shape with a central penetration by die-casting; Step 3: Dry the briquette using dry mixed gas at standard temperature, so that the pressure resistance of a single briquette is greater than 800N; Step 4: According to the standard temperature, the coal briquettes are stacked and sent into the coke oven carbonization chamber for carbonization until maturity to obtain foundry coke.
2. The method for producing foundry coke in a large coke oven using only shaped coal according to claim 1, characterized in that: In step 1, the liquid agent comprises 0.5-3.0% of the total dry weight of the material and 12-16% of the total dry weight of the material.
3. The method for producing foundry coke in a large coke oven using only shaped coal according to claim 1 or 2, characterized in that: In step 1, the raw coal is crushed to a particle size of less than 3 mm. Among them, the proportion of less than 1 mm is greater than or equal to 70%, and the proportion of 0.5 mm is greater than or equal to 40%.
4. The method for producing foundry coke in a large-scale coke oven using only shaped coal according to claim 1, characterized in that: The standard coal shape in step 2 includes a cylindrical or prism shape with a diameter of 120 mm and a height of 120 mm. The coal mold is formed with a boss structure, the end face of the boss is 30% smaller than the end face of the coal mold, the height is 3-7mm, and the diameter of the central through hole of the coal mold is greater than or equal to 25mm.
5. The method for producing foundry coke in a large-scale coke oven using only shaped coal according to claim 1, characterized in that: In step 2, the die-casting pressure is greater than or equal to 20 MPa.
6. The method for producing foundry coke in a large-scale coke oven using only shaped coal according to claim 1, characterized in that: The mixed gas in step 3 is a mixture of the exhaust gas from the coke oven combustion chamber and air.
7. The method for producing foundry coke in a large coke oven using only shaped coal according to claim 1 or 5, characterized in that: In step 3, the drying moisture is less than 3%.
8. The method for producing foundry coke in a large-scale coke oven using only shaped coal according to claim 1, characterized in that: The standard temperature in steps 3 and 4 is 80-130°C.
9. The method for producing foundry coke in a large-scale coke oven using only shaped coal according to claim 1, characterized in that: Step 4: The medium-sized coal is stacked in a single layer and sent into the coke oven carbonization chamber.
10. The method for producing foundry coke in a large-scale coke oven using only shaped coal according to claim 1 or 9, characterized in that: In step 4, the coke matures when the temperature in the coke oven carbonization chamber reaches 1200°C-1300°C.