Efficient cost-reducing coal-fired power generation method

Abstract

The invention belongs to the technical field of coal-fired power generation, and provides an efficient cost-reducing coal-fired power generation method which specifically comprises the following steps: S1, performing crushing and primary drying treatment on coal; s2, the dried coal is subjected to grinding treatment, secondary drying treatment and dust removal, and pulverized coal is obtained; s3, mixing the pulverized coal obtained in the step S2 with a catalyst, and feeding the mixture into a boiler through a combustor for combustion reaction to form combustible synthesis gas; s4, the combustible synthesis gas is pressurized through a gas compressor and then sprayed into the boiler through an ejector to be combusted, and water vapor is formed; and S5, the steam turbine set is driven by the water vapor to do work so as to drive a generator to generate power. According to the method, the main catalyst, the auxiliary catalyst and the pulverized coal are uniformly mixed and then added into the boiler, the porosity of the coal is increased, and coal particles can be in full contact with oxygen in air, so that the combustion of the coal is promoted, the coal saving rate is more than 4%, and the cost is saved.

Description

Technical Field

[0001] The present invention belongs to the technical field of coal-fired power generation, and particularly relates to a coal-fired power generation method with high efficiency and cost reduction. Background Art

[0002] Coal has a wide range of uses. For example, it can be used for power generation, and there are various ways of power generation, such as biomass power generation, wind power generation, and hydroelectric power generation.

[0003] In the prior art, coal is often used for power generation. Coal combustion generates electricity through a gas turbine. However, larger coal blocks contain a high amount of ash powder and sulfur due to incomplete combustion. The ash powder and sulfur are entrained in the flue gas and deposited on the surface of the channels and blades through the turbine, corroding the equipment. The deposited dust will block the channels in the turbine, and due to the deposition of fine particles on the heat exchange surface, the thermal efficiency will be damaged. At the same time, in the prior art, there is also a steam engine power generation technology. Steam engine power generation usually involves coal combustion reacting with air to release heat to generate high-pressure steam, and then the steam expands through the turbine in sequence to generate mechanical energy or electrical energy. Although the steam engine power generation technology does not involve the influence of flue gas ash powder deposition and corrosion, the remaining heat and steam generated in the actual production process cannot be well utilized. Coal-fired power generation also emits a large amount of pollutants during power generation, such as SO2, soot, NO x and CO2, etc.

[0004] Therefore, further improving the utilization efficiency of coal, reducing coal consumption and pollutant emissions has become an important and urgent task for the power industry to achieve sustainable development. Summary of the Invention

[0005] The purpose of the present invention is to provide a coal-fired power generation method with high efficiency and cost reduction to solve one of the problems mentioned in the background art.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A coal-fired power generation method with high efficiency and cost reduction includes the following steps:

[0008] S1. Crush and perform primary drying on the coal;

[0009] S2. Perform pulverization and secondary drying on the coal after drying treatment, and obtain pulverized coal after dust removal;

[0010] S3. Mix the pulverized coal obtained in step S2 with a catalyst, and then enter the boiler through a burner for combustion reaction to form combustible syngas;

[0011] S4. The combustible syngas is pressurized by a gas compressor and then sprayed into the boiler through an ejector for combustion to form water vapor;

[0012] S5. Use steam to drive a steam turbine unit to do work and then drive a generator to generate electricity.

[0013] As a preferred embodiment of the present invention, in step S1, the moisture content in the primary drying treatment is 18wt% - 20wt%.

[0014] As a preferred embodiment of the present invention, in step S2, the moisture content in the secondary drying treatment is 10wt% - 12wt%.

[0015] As a preferred embodiment of the present invention, in step S2, the particle size of the pulverized coal is 6 - 10mm.

[0016] As a preferred embodiment of the present invention, in step S3, the addition amount of the catalyst is 0.04% - 0.06% of the coal.

[0017] As a preferred embodiment of the present invention, in step S3, the catalyst includes a main catalyst and a promoter.

[0018] As a preferred embodiment of the present invention, the catalyst is potassium permanganate.

[0019] As a preferred embodiment of the present invention, the promoter is iron(III) oxide.

[0020] As a preferred embodiment of the present invention, the mass ratio of the compounding of the main catalyst and the promoter is (1 - x):x, where x is the dosage of the promoter, and 0.04 ≤ x ≤ 0.06.

[0021] Advantages of the present invention:

[0022] In the present invention, the main catalyst and the promoter are uniformly mixed with the pulverized coal and then added to the boiler. Under heating conditions, the main catalyst potassium permanganate will decompose and release oxygen, increasing the porosity of the coal, enabling the coal particles to fully contact with the oxygen in the air, improving the release rate of volatile components in the coal, and thus promoting the combustion of the coal. At the same time, under the action of the promoter iron(III) oxide, the coal is promoted to burn fully, stabilizing the combustion effect, and these two catalysts can act on the entire combustion process, thereby greatly improving the burnout rate of the coal.

[0023] The present invention provides an efficient coal-fired power generation method with cost reduction. The operation process is simple, reducing the invisible damage to operating equipment, significantly improving economic benefits, and reducing the emissions of harmful gases and dust. Specific embodiments

[0024] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0025] Embodiment 1

[0026] This embodiment provides a coal-fired power generation method for efficient cost reduction, including the following steps:

[0027] S1. Crush and perform primary drying on coal (taken from Yangquan bituminous coal in Shanxi Province, 5000t), and dry it until the moisture content is 18wt%;

[0028] S2. Grind and perform secondary drying on the dried coal, and dry it until the moisture content is 11wt%. After dust removal, pulverized coal (with a particle size of 6mm) is obtained;

[0029] S3. Mix the pulverized coal obtained in step S2 with a catalyst (including 1.92t of potassium permanganate and 0.08t of iron oxide), and then enter the boiler through a burner for combustion reaction to form combustible synthesis gas;

[0030] S4. Pressurize the combustible synthesis gas with a gas compressor and then spray it into the boiler through an ejector for combustion to form water vapor;

[0031] S5. Use the water vapor to drive a steam turbine to do work and thus drive a generator to generate electricity.

[0032] Embodiment 2

[0033] This embodiment provides a coal-fired power generation method for efficient cost reduction, including the following steps:

[0034] S1. Crush and perform primary drying on coal (taken from Yangquan bituminous coal in Shanxi Province, 5000t), and dry it until the moisture content is 18wt%;

[0035] S2. Grind and perform secondary drying on the dried coal, and dry it until the moisture content is 11wt%. After dust removal, pulverized coal (with a particle size of 6mm) is obtained;

[0036] S3. Mix the pulverized coal obtained in step S2 with a catalyst (including 1.88t of potassium permanganate and 0.12t of iron oxide), and then enter the boiler through a burner for combustion reaction to form combustible synthesis gas;

[0037] S4. Pressurize the combustible synthesis gas with a gas compressor and then spray it into the boiler through an ejector for combustion to form water vapor;

[0038] S5. Drive a steam turbine to do work with water vapor, thereby driving a generator to generate electricity.

[0039] Example 3

[0040] This example provides a coal-fired power generation method for high efficiency and cost reduction, including the following steps:

[0041] S1. Crush and perform primary drying on coal (taken from Yangquan bituminous coal in Shanxi Province, 5000 t), and dry it to a moisture content of 18 wt%.

[0042] S2. Grind and perform secondary drying on the dried coal, and dry it to a moisture content of 11 wt%. After dust removal, pulverized coal (particle size of 6 mm) is obtained.

[0043] S3. Mix the pulverized coal obtained in step S2 with a catalyst (including 2.85 t of potassium permanganate and 0.15 t of iron(III) oxide), and then enter the boiler through a burner for combustion reaction to form combustible syngas.

[0044] S4. Pressurize the combustible syngas with a gas compressor and then inject it into the boiler through an ejector for combustion to form water vapor.

[0045] S5. Drive a steam turbine to do work with water vapor, thereby driving a generator to generate electricity.

[0046] Example 4

[0047] This example provides a coal-fired power generation method for high efficiency and cost reduction, including the following steps:

[0048] S1. Crush and perform primary drying on coal (taken from Yangquan bituminous coal in Shanxi Province, 5000 t), and dry it to a moisture content of 19 wt%.

[0049] S2. Grind and perform secondary drying on the dried coal, and dry it to a moisture content of 10 wt%. After dust removal, pulverized coal (particle size of 6 mm) is obtained.

[0050] S3. Mix the pulverized coal obtained in step S2 with a catalyst (including 1.92 t of potassium permanganate and 0.08 t of iron(III) oxide), and then enter the boiler through a burner for combustion reaction to form combustible syngas.

[0051] S4. Pressurize the combustible syngas with a gas compressor and then inject it into the boiler through an ejector for combustion to form water vapor.

[0052] S5. Drive a steam turbine to do work with water vapor, thereby driving a generator to generate electricity.

[0053] Example 5

[0054] This embodiment provides a coal-fired power generation method for efficiently reducing costs, including the following steps:

[0055] S1. Crush and perform primary drying on coal (taken from Yangquan bituminous coal in Shanxi Province, 5000t), and dry it to a moisture content of 20wt%.

[0056] S2. Grind and perform secondary drying on the dried coal, and dry it to a moisture content of 12wt%. After dust removal, pulverized coal (with a particle size of 9.5mm) is obtained.

[0057] S3. Mix the pulverized coal obtained in step S2 with a catalyst (including 1.92t of potassium permanganate and 0.08t of iron(III) oxide), and then pass it through a burner into a boiler for combustion reaction to form combustible synthesis gas.

[0058] S4. Pressurize the combustible synthesis gas with a gas compressor and then inject it into the boiler through an ejector for combustion to form steam.

[0059] S5. Use the steam to drive a steam turbine to do work and thus drive a generator to generate electricity.

[0060] Comparative Example 1

[0061] This comparative example provides a coal-fired power generation method for efficiently reducing costs. No catalyst is added during the process of this method, including the following steps:

[0062] S1. Crush and perform primary drying on coal (taken from Yangquan bituminous coal in Shanxi Province, 5000t), and dry it to a moisture content of 18wt%.

[0063] S2. Grind and perform secondary drying on the dried coal, and dry it to a moisture content of 11wt%. After dust removal, pulverized coal (with a particle size of 6mm) is obtained.

[0064] S3. Pass the pulverized coal obtained in step S2 through a burner into a boiler for combustion reaction to form combustible synthesis gas.

[0065] S4. Pressurize the combustible synthesis gas with a gas compressor and then inject it into the boiler through an ejector for combustion to form steam.

[0066] S5. Use the steam to drive a steam turbine to do work and thus drive a generator to generate electricity.

[0067] Comparative Example 2

[0068] This comparative example provides a coal-fired power generation method for efficiently reducing costs. Only potassium permanganate catalyst is added during the process of this method, including the following steps:

[0069] S1. Crush and perform primary drying on the coal (5000 t of bituminous coal from Yangquan, Shanxi Province) until the moisture content reaches 18 wt%.

[0070] S2. Grind and perform secondary drying on the dried coal until the moisture content reaches 11 wt%, and obtain pulverized coal (particle size of 6 mm) after dust removal.

[0071] S3. Mix the pulverized coal obtained in step S2 with 2 t of potassium permanganate catalyst, and then enter the boiler through a burner for combustion reaction to form combustible synthesis gas.

[0072] S4. Pressurize the combustible synthesis gas with a gas compressor and then spray it into the boiler through an ejector for combustion to form steam.

[0073] S5. Use the steam to drive a steam turbine to do work and thus drive a generator to generate electricity.

[0074] Comparative Example 3

[0075] This comparative example provides a coal-fired power generation method for high efficiency and cost reduction. Only iron oxide catalyst is added during the process, including the following steps:

[0076] S1. Crush and perform primary drying on the coal (5000 t of bituminous coal from Yangquan, Shanxi Province) until the moisture content reaches 18 wt%.

[0077] S2. Grind and perform secondary drying on the dried coal until the moisture content reaches 11 wt%, and obtain pulverized coal (particle size of 6 mm) after dust removal.

[0078] S3. Mix the pulverized coal obtained in step S2 with 2 t of iron oxide catalyst, and then enter the boiler through a burner for combustion reaction to form combustible synthesis gas.

[0079] S4. Pressurize the combustible synthesis gas with a gas compressor and then spray it into the boiler through an ejector for combustion to form steam.

[0080] S5. Use the steam to drive a steam turbine to do work and thus drive a generator to generate electricity.

[0081] Test the combustion efficiency of the coal used in Examples 1 - 5 and Comparative Examples 1 - 3, and calculate the coal saving rate compared with the coal combustion in Comparative Example 1. The test results are shown in Table 1:

[0082] Table 1

[0083]

[0084] As can be seen from Table 1, compared with Comparative Example 1, the coal saving rates of Examples 1-5 are all higher than 4%, and the coal saving rates in Comparative Example 2 and Comparative Example 3 are lower than 4%. The coal-fired power generation methods provided in Examples 1-5 all added potassium permanganate catalyst and iron oxide catalyst. Only potassium permanganate catalyst was added in Comparative Example 2, and only iron oxide catalyst was added in Comparative Example 3. Thus, it can be seen that by uniformly mixing and burning the main and auxiliary catalysts with pulverized coal in the present invention, coal particles can be in full contact with oxygen in the air, the volatilization rate of volatile components in coal is increased, thereby promoting the combustion of coal and improving the burnout rate of coal.

[0085] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0086] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A coal-fired power generation method with high efficiency and low cost, characterized in that: The following steps are involved: S1. crushing the coal and performing primary drying; S2, grinding and secondary drying the dried coal to obtain coal powder after dust removal; S3, mixing the pulverized coal obtained in step S2 with the catalyst and passing the mixture through a burner into a boiler for combustion reaction to form combustible synthesis gas; S4, the combustible synthesis gas is pressurized by the gas compressor and then sprayed into the boiler through the ejector for combustion to form water vapor; S5. Use water vapor to drive the steam turbine unit to do work and then drive the generator to generate electricity.

2. The method for coal-fired power generation with high efficiency and low cost according to claim 1, characterized in that: The moisture content in the primary drying process in step S1 is 18 wt % to 20 wt %.

3. The method for coal-fired power generation with high efficiency and low cost according to claim 1, characterized in that: The moisture content in the secondary drying process in step S2 is 10 wt % to 12 wt %.

4. The method for coal-fired power generation with high efficiency and low cost according to claim 1, characterized in that: The particle size of the coal powder in step S2 is 6 to 10 mm.

5. The method for coal-fired power generation with high efficiency and low cost according to claim 1, characterized in that: The amount of the catalyst added in step S3 is 0.04% to 0.06% of the coal.

6. The high-efficiency and cost-reducing coal-fired power generation method according to claim 1, characterized in that: The catalyst in step S3 includes a main catalyst and a co-catalyst.

7. A high-efficiency and cost-reducing coal-fired power generation method according to claim 6, characterized in that: The catalyst is potassium permanganate.

8. The high-efficiency and cost-reducing coal-fired power generation method according to claim 6, characterized in that: The promoter is ferric oxide.

9. The high-efficiency and cost-reducing coal-fired power generation method according to claim 6, characterized in that: The mass ratio of the main catalyst to the co-catalyst is (1-x):x, where x is the amount of the co-catalyst, and 0.04≤x≤0.06.

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