Wet desulfurizer for thermal power plant as well as preparation method and application of wet desulfurizer

Abstract

The embodiment of the invention discloses a wet desulfurizer for a thermal power plant and a preparation method and application of the wet desulfurizer. The wet desulfurizer for the thermal power plant is prepared from the following components in parts by weight: 30-65 parts of bentonite, 12-38 parts of lime, 4.5-10 parts of vermiculite powder, 1-5 parts of sodium carboxymethyl starch, 1.5-5 parts of activated carbon and 150-200 parts of water. The wet desulfurizer provided by the invention not only can effectively remove sulfur dioxide in flue gas, but also can inhibit the release of SO3 in fly ash, so that the desulfurization efficiency is greatly improved, and due to the mutual cooperation of the components, the operation stability of a desulfurization process using the product is relatively good, so that the wet desulfurizer is relatively wide in application range and relatively high in applicability. The raw materials are wide in source, low in price, easy to obtain and suitable for large-scale batch production.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of desulfurization agents, and in particular to a wet desulfurization agent for thermal power plants, its preparation method and application. Background Art

[0002] The installed capacity of thermal power generation in China has exceeded 1 billion kilowatts, accounting for more than 65% of the total installed power capacity; about 480 million tons of coal are burned every year.

[0003] At present, the vast majority of thermal power plants in China have implemented desulfurization technical transformations. For the treatment of sulfur dioxide, the lime-gypsum wet circulation process is generally adopted, and its desulfurization efficiency can usually reach more than 95%, which is very effective for controlling sulfur dioxide emissions. The process has relatively high control requirements for flue gas parameters (such as temperature, sulfur content, etc.), and the operation stability is relatively poor, and fine regulation is required. Summary of the Invention

[0004] Therefore, the embodiments of the present invention provide a wet desulfurization agent for thermal power plants, its preparation method and application. The desulfurization agent has high desulfurization efficiency and good dynamic operation stability at the same time.

[0005] In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:

[0006] According to the first aspect of the embodiments of the present invention, the present invention provides a wet desulfurization agent for thermal power plants. The wet desulfurization agent for thermal power plants is made of the following components by weight: 30-65 parts of bentonite, 12-38 parts of lime, 4.5-10 parts of vermiculite powder, 1-5 parts of sodium carboxymethyl starch, 1.5-5 parts of activated carbon, and 150-200 parts of water.

[0007] In some preferred embodiments, the wet desulfurization agent for thermal power plants is made of the following components by weight: 40-50 parts of bentonite, 20-30 parts of lime, 5-8 parts of vermiculite powder, 2-4 parts of sodium carboxymethyl starch, 3-5 parts of activated carbon, and 150-180 parts of water.

[0008] In some preferred embodiments, the wet desulfurization agent for thermal power plants is made of the following components by weight: 45 parts of bentonite, 25 parts of lime, 6 parts of vermiculite powder, 3 parts of sodium carboxymethyl starch, 4 parts of activated carbon, and 180 parts of water.

[0009] According to the second aspect of the embodiments of the present invention, the present invention provides a preparation method of the wet desulfurization agent for thermal power plants as described in any one of the above, and the method includes:

[0010] Adding bentonite, lime, vermiculite powder, sodium carboxymethyl starch and activated carbon into water, and stirring evenly to obtain a suspension;

[0011] Dry the suspension, then carry out carbonization treatment, pulverize and sieve to obtain the wet flue gas desulfurizer for thermal power plants.

[0012] In some preferred embodiments, the conditions for stirring are: 1000 - 2000 r / min, 20 - 40 min.

[0013] In some preferred embodiments, the drying temperature is 110 - 140 °C; the conditions for carbonization treatment are: 600 - 800 °C, 2 - 3 h.

[0014] In some preferred embodiments, the mesh number of the sieve is 60 - 100 meshes.

[0015] According to the third aspect of the embodiments of the present invention, the present invention provides the application of the above-mentioned wet flue gas desulfurizer for thermal power plants in the flue gas desulfurization treatment of thermal power plants.

[0016] The embodiments of the present invention have the following advantages:

[0017] (1) The wet flue gas desulfurizer provided by the present invention can not only effectively remove sulfur dioxide in the flue gas, but also inhibit the release of SO3 in fly ash, thereby greatly improving the desulfurization efficiency. And due to the mutual cooperation between components, the desulfurization process using this product has relatively good operation stability. Therefore, its application range is relatively wide and its applicability is relatively strong.

[0018] (2) The raw materials used in the present invention are widely sourced, inexpensive, and easily available, and are suitable for large-scale batch production. Specific Embodiments

[0019] The following specific embodiments illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0020] Example 1

[0021] This example provides a wet flue gas desulfurizer for thermal power plants. By weight, its raw materials are: 50 parts of bentonite, 32 parts of lime, 4.8 parts of vermiculite powder, 4 parts of sodium carboxymethyl starch, 3 parts of activated carbon, and 160 parts of water.

[0022] The preparation method of the above-mentioned wet flue gas desulfurizer for thermal power plants includes:

[0023] (1) Add bentonite, lime, vermiculite powder, sodium carboxymethyl starch, and activated carbon into water, and stir at 2000 r / min for 20 min to obtain a suspension;

[0024] (2) Dry the suspension at 110 °C until there is no moisture, then carbonize it at 800 °C for 3 h, crush it, and pass it through an 80-mesh sieve to obtain the wet flue gas desulfurization agent for thermal power plants.

[0025] Example 2

[0026] This example provides a wet flue gas desulfurization agent for thermal power plants. By weight, its raw materials are: 45 parts of bentonite, 25 parts of lime, 6 parts of vermiculite powder, 3 parts of sodium carboxymethyl starch, 4 parts of activated carbon, and 180 parts of water.

[0027] The preparation method of the above wet flue gas desulfurization agent for thermal power plants includes:

[0028] (1) Add bentonite, lime, vermiculite powder, sodium carboxymethyl starch, and activated carbon to water, and stir at 1800 r / min for 35 min to obtain a suspension;

[0029] (2) Dry the suspension at 120 °C until there is no moisture, then carbonize it at 750 °C for 2 h, crush it, and pass it through an 80-mesh sieve to obtain the wet flue gas desulfurization agent for thermal power plants.

[0030] Example 3

[0031] This example provides a wet flue gas desulfurization agent for thermal power plants. By weight, its raw materials are: 63 parts of bentonite, 20 parts of lime, 6 parts of vermiculite powder, 1 part of sodium carboxymethyl starch, 3 parts of activated carbon, and 200 parts of water.

[0032] The preparation method of the above wet flue gas desulfurization agent for thermal power plants includes:

[0033] (1) Add bentonite, lime, vermiculite powder, sodium carboxymethyl starch, and activated carbon to water, and stir at 1500 r / min for 30 min to obtain a suspension;

[0034] (2) Dry the suspension at 140 °C until there is no moisture, then carbonize it at 800 °C for 3 h, crush it, and pass it through an 80-mesh sieve to obtain the wet flue gas desulfurization agent for thermal power plants.

[0035] Example 4

[0036] This example provides a wet flue gas desulfurization agent for thermal power plants. By weight, its raw materials are: 30 parts of bentonite, 38 parts of lime, 8.5 parts of vermiculite powder, 3 parts of sodium carboxymethyl starch, 1.5 parts of activated carbon, and 180 parts of water.

[0037] The preparation method of the above wet flue gas desulfurization agent for thermal power plants includes:

[0038] (1) Add bentonite, lime, vermiculite powder, sodium carboxymethyl starch, and activated carbon to water, and stir at 1500 r / min for 40 min to obtain a suspension;

[0039] (2) Dry the suspension at 140 °C until there is no moisture, then carbonize it at 600 °C for 2 h, crush it, and pass it through an 80-mesh sieve to obtain the wet flue gas desulfurization agent for thermal power plants.

[0040] Example 5

[0041] This example provides a wet flue gas desulfurization agent for thermal power plants. By weight, its raw materials are: 58 parts of bentonite, 12 parts of lime, 10 parts of vermiculite powder, 5 parts of sodium carboxymethyl starch, 4.5 parts of activated carbon, and 160 parts of water.

[0042] The preparation method of the above wet flue gas desulfurization agent for thermal power plants includes:

[0043] (1) Add bentonite, lime, vermiculite powder, sodium carboxymethyl starch, and activated carbon to water, and stir at 1800 r / min for 30 min to obtain a suspension;

[0044] (2) Dry the suspension at 120 °C until there is no moisture, then carbonize it at 700 °C for 2.5 h, crush it, and pass it through an 80-mesh sieve to obtain the wet flue gas desulfurization agent for thermal power plants.

[0045] Comparative Example 1

[0046] This example provides a wet flue gas desulfurization agent for thermal power plants. By weight, its raw materials are: 45 parts of bentonite, 25 parts of lime, 3 parts of sodium carboxymethyl starch, 4 parts of activated carbon, and 180 parts of water.

[0047] The preparation method of the above wet flue gas desulfurization agent for thermal power plants includes:

[0048] (1) Add bentonite, lime, sodium carboxymethyl starch, and activated carbon to water, and stir at 1500 r / min for 40 min to obtain a suspension;

[0049] (2) Dry the suspension at 120 °C until there is no moisture, then carbonize it at 750 °C for 2 h, crush it, and pass it through an 80-mesh sieve to obtain the wet flue gas desulfurization agent for thermal power plants.

[0050] Comparative Example 2

[0051] This example provides a wet flue gas desulfurization agent for thermal power plants. By weight, its raw materials are: 45 parts of bentonite, 25 parts of lime, 6 parts of vermiculite powder, 3 parts of sodium carboxymethyl starch, and 180 parts of water.

[0052] The preparation method of the above wet flue gas desulfurization agent for thermal power plants includes:

[0053] (1) Add bentonite, lime, vermiculite powder, and sodium carboxymethyl starch to water, and stir at 1500 r / min for 40 min to obtain a suspension;

[0054] (2) Dry the suspension at 120 °C until there is no moisture, then carbonize it at 750 °C for 2 h, crush it, and pass it through an 80-mesh sieve to obtain the wet flue gas desulfurizer for thermal power plants.

[0055] Test Example 1

[0056] Experiment on the absorption of sulfur dioxide by the wet flue gas desulfurizer

[0057] The experimental method is as follows: Mix the wet flue gas desulfurizer according to a mass ratio of 1:50 to obtain the absorption material, and adjust the temperature of the absorption material to be stable at 50 °C. Collect the flue gas discharged from the simulated thermal power plant flue gas emission device, and control the temperature and concentration of SO2. Among them, the temperature of simulated flue gas 1 is 80 °C, and the sulfur content is 2%; the temperature of simulated flue gas 2 is 100 °C, and the sulfur content is 4%; the temperature of simulated flue gas 3 is 140 °C, and the sulfur content is 6%.

[0058] The flue gas is introduced from the bottom of the packing tower, and the absorption material is introduced from the top of the packing tower to make the flue gas and the absorption material fully contact. Use a flue gas analyzer to measure the concentration of SO2 in the mixed gas entering and leaving the packing tower to evaluate the effect of wet flue gas desulfurization.

[0059] The test results of the desulfurization efficiency of the wet flue gas desulfurizers in Examples 1-5 and Comparative Examples 1-2 for different flue gases are shown in Table 1 below.

[0060] Table 1

[0061]

[0062]

[0063] Although the present invention has been described in detail above with general descriptions and specific examples, based on the present invention, some modifications or improvements can be made, which are obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection required by the present invention.

Claims

1. A wet desulfurization agent for a thermal power plant, characterized in that: The thermal power plant wet desulfurization agent is made of the following components by weight: 30-65 parts of bentonite, 12-38 parts of lime, 4.5-10 parts of vermiculite powder, 1-5 parts of sodium carboxymethyl starch, 1.5-5 parts of activated carbon, and 150-200 parts of water.

2. The wet desulfurization agent for thermal power plants according to claim 1, characterized in that: The thermal power plant wet desulfurization agent is made of the following components by weight: 40-50 parts of bentonite, 20-30 parts of lime, 5-8 parts of vermiculite powder, 2-4 parts of sodium carboxymethyl starch, 3-5 parts of activated carbon, and 150-180 parts of water.

3. The wet desulfurization agent for thermal power plants according to claim 1, characterized in that: The thermal power plant wet desulfurization agent is made of the following components by weight: 45 parts of bentonite, 25 parts of lime, 6 parts of vermiculite powder, 3 parts of sodium carboxymethyl starch, 4 parts of activated carbon, and 180 parts of water.

4. The method for preparing a wet desulfurization agent for a thermal power plant according to any one of claims 1 to 3, characterized in that: The method comprises: Add bentonite, lime, vermiculite powder, sodium carboxymethyl starch and activated carbon into water and stir evenly to obtain a suspension; The suspension is dried, then carbonized, crushed and sieved to obtain the wet desulfurization agent for thermal power plants.

5. The method for preparing a wet desulfurization agent for a thermal power plant according to claim 4, characterized in that: The stirring conditions are: 1000-2000 r / min, 20-40 min.

6. The method for preparing a wet desulfurization agent for a thermal power plant according to claim 4, characterized in that: The drying temperature is 110-140° C.; the carbonization treatment conditions are: 600-800° C., 2-3 hours.

7. The method for preparing a wet desulfurization agent for a thermal power plant according to claim 4, characterized in that: The mesh size of the sieve is 60 to 100 meshes.

8. Use of the wet desulfurization agent for thermal power plants according to claim 1 in flue gas desulfurization treatment in thermal power plants.

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