Macromolecule bonding calcium-based flue gas desulfurizer and preparation method thereof

Abstract

The invention relates to the technical field of desulfurizers, and discloses a macromolecular adhesive calcium-based flue gas desulfurizer and a preparation method thereof.The desulfurizer comprises, by mass, 300-450 parts of slaked lime, 30-120 parts of calcium carbonate and 3-30 parts of auxiliaries, and the ratio of the slaked lime to the calcium carbonate to the auxiliaries is (300-450): (30-120): (3-30). The desulfurizer obtained by the invention has relatively good activity and relatively good desulfurization effect.

Description

Technical Field

[0001] The invention relates to the technical field of desulfurizing agents, and in particular to a polymer-bonded calcium-based flue gas desulfurizing agent and a preparation method thereof. Background Art

[0002] Flue gas desulfurization (FGD) is based on chemical or physical principles to fix SO2 in flue gas into solid or solution absorbents, thereby achieving efficient removal of SO2 in flue gas. Flue gas desulfurization technology can be traced back to the middle of the 20th century. With the gradual increase in environmental awareness, countries have begun to vigorously carry out research on flue gas desulfurization technology. In the 21st century, flue gas desulfurization technology has been widely used and promoted, becoming an important means of controlling SO2 worldwide.

[0003] Calcium-based desulfurizers are the most commonly used desulfurizers and are widely used in the flue gas desulfurization process. Currently, most calcium-based desulfurizers on the market are mainly composed of calcium hydroxide and binders, with a single component. When the calcium hydroxide content is high, the desulfurizer has low strength and is easy to pulverize; when the calcium hydroxide content is low, the desulfurization effect is affected. In addition, the flue gas emission conditions are changeable, and calcium-based desulfurizers also have the disadvantages of low utilization rate and insufficient low-temperature reaction activity.

[0004] Therefore, through the optimization of the formula, a new type of high-strength and high-efficiency calcium-based flue gas desulfurizer was developed, which takes into account the desulfurization efficiency, strength and cost, so that it can be widely used in various process occasions with large changes in flue gas volume. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a polymer-bonded calcium-based flue gas desulfurizer and a preparation method thereof. The desulfurizer obtained by the present invention has good activity and good desulfurization effect.

[0006] The invention provides a polymer-bonded calcium-based flue gas desulfurizer, which comprises slaked lime, calcium carbonate and an auxiliary agent. The mass ratio of the slaked lime, calcium carbonate and the auxiliary agent is (300 parts-450 parts): (30 parts-120 parts): (3 parts-30 parts).

[0007] Furthermore, the slaked lime is slaked lime having a mass fraction of calcium hydroxide higher than 80%.

[0008] Furthermore, the auxiliary agent includes one or more of clay, acrylic acid, sodium stearate, sodium polyacrylate, polyacrylamide, cellulose, sodium bicarbonate, magnesium oxide, carbide slag, kaolin, electrolytic manganese dioxide, iron oxide and alum.

[0009] The present invention also provides a method for preparing the polymer-bonded calcium-based flue gas desulfurizer, the method comprising: S1: drying slaked lime and mixing the dried slaked lime with calcium carbonate; S2: mixing the mixed product in S1 with an auxiliary agent to obtain an intermediate product; S3: The intermediate product is stirred and kneaded with water, and dried to obtain a polymer-bonded calcium-based flue gas desulfurizer.

[0010] Furthermore, the drying temperature in S1 is 160° C.-200° C., and the drying time is 1.5 h-2.5 h.

[0011] Furthermore, based on mass, the ratio of the auxiliary agent to water is (3 parts-30 parts):(110 parts-170 parts).

[0012] Furthermore, the slaked lime is slaked lime having a mass fraction of calcium hydroxide higher than 80%.

[0013] Furthermore, the auxiliary agent includes one or more of clay, acrylic acid, sodium stearate, sodium polyacrylate, polyacrylamide, cellulose, sodium bicarbonate, magnesium oxide, carbide slag, kaolin, electrolytic manganese dioxide, iron oxide and alum.

[0014] Furthermore, based on mass, the ratio of slaked lime, calcium carbonate and auxiliary agent is (300 parts-450 parts):(30 parts-120 parts):(3 parts-30 parts).

[0015] Furthermore, the drying temperature in S3 is 120° C.-200° C., and the drying time is 20 min-50 min.

[0016] Furthermore, the polymer-bonded calcium-based flue gas desulfurizer is a cylindrical or four-leaf clover-shaped solid strip with a diameter of 4mm-7mm.

[0017] The embodiments of the present invention have the following technical effects: In the present invention, one or more compounds with molecular bonding properties are used to increase the radial strength while ensuring the porosity of the present invention. Better porosity is also beneficial to the desulfurization effect of the product. The present invention additionally adds calcium carbonate. Since calcium carbonate has colloid activation properties and good stability and can react with sulfur dioxide, the addition of calcium carbonate can enhance the desulfurization effect of the product, increase the desulfurization activity and product stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 The present invention provides a flow chart of a method for preparing a polymer-bonded calcium-based flue gas desulfurizer. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0021] In a first aspect, some embodiments of the present invention provide a polymer-bonded calcium-based flue gas desulfurizer, which includes slaked lime, calcium carbonate and an additive. By mass, the ratio of slaked lime, calcium carbonate and the additive is (300 parts-450 parts): (30 parts-120 parts): (3 parts-30 parts).

[0022] In some embodiments, the slaked lime is slaked lime having a mass fraction of calcium hydroxide higher than 80%.

[0023] In some embodiments, the auxiliary agent includes one or more of clay, acrylic acid, sodium stearate, sodium polyacrylate, polyacrylamide, cellulose, sodium bicarbonate, magnesium oxide, carbide slag, kaolin, electrolytic manganese dioxide, iron oxide and alum.

[0024] In a second aspect, some embodiments of the present invention also provide a method for preparing the polymer-bonded calcium-based flue gas desulfurizer, the method comprising: S1: drying slaked lime and mixing the dried slaked lime with calcium carbonate; S2: mixing the mixed product in S1 with an auxiliary agent to obtain an intermediate product; S3: The intermediate product is stirred and kneaded with water, and dried to obtain a polymer-bonded calcium-based flue gas desulfurizer.

[0025] In some embodiments, the drying temperature in S1 is 160° C.-200° C., and the drying time is 1.5 h-2.5 h.

[0026] In some embodiments, the ratio of the auxiliary agent to water is (3 parts-30 parts) to (110 parts-170 parts) by mass.

[0027] In some embodiments, the slaked lime is slaked lime having a mass fraction of calcium hydroxide higher than 80%.

[0028] In some embodiments, the auxiliary agent includes one or more of clay, acrylic acid, sodium stearate, sodium polyacrylate, polyacrylamide, cellulose, sodium bicarbonate, magnesium oxide, carbide slag, kaolin, electrolytic manganese dioxide, iron oxide and alum.

[0029] In some embodiments, the ratio of slaked lime, calcium carbonate and auxiliary agent is (300 parts-450 parts) : (30 parts-120 parts) : (3 parts-30 parts) by mass.

[0030] In some embodiments, the drying temperature in S3 is 120° C.-200° C., and the drying time is 20 min-50 min.

[0031] In some embodiments, the polymer-bonded calcium-based flue gas desulfurizer is a cylindrical or four-leaf clover-shaped solid strip with a diameter of 4 mm to 7 mm.

[0032] The following is described in conjunction with specific embodiments: The preparation method of the embodiment of the present invention is as follows Figure 1 shown.

[0033] Embodiment 1: The slaked lime is dried at 180°C for 2 hours, and the dried slaked lime (calcium hydroxide content is more than 80%) is mixed with calcium carbonate; the mixed product is mixed with an auxiliary agent to obtain an intermediate product; a corresponding amount of water is added for stirring and kneading, and after stirring and kneading for 20-30 minutes, the product is extruded by an extruder to obtain a cylindrical or four-leaf clover-shaped solid strip with a diameter of 4-7mm, and dried at 160°C for 50 minutes to obtain a calcium-based desulfurizer product with calcium-based soil as the main adsorbent, and its water content is controlled at 0-6%. The auxiliary agent includes cellulose, polyacrylamide, and sodium polyacrylate. In terms of mass, the ratio of slaked lime, calcium carbonate and auxiliary agent is 400:80:20. Among the auxiliary agents, the mass ratio of cellulose, polyacrylamide and sodium polyacrylate is 5:1:1. The mass ratio of auxiliary agent to water is 20:140.

[0034] Embodiment 2: The slaked lime is dried at 180°C for 2 hours, and the dried slaked lime (calcium hydroxide content is more than 80%) is mixed with calcium carbonate; the mixed product is mixed with an auxiliary agent to obtain an intermediate product; a corresponding amount of water is added for stirring and kneading, and after stirring and kneading for 20-30 minutes, the product is extruded by an extruder into a cylindrical or four-leaf clover-shaped solid strip with a diameter of 4-7mm, and dried at 160°C for 50 minutes to obtain a calcium-based desulfurizer product with calcium-based soil as the main adsorbent, and its water content is controlled at 0-6%. The auxiliary agent includes cellulose, polyacrylamide, and sodium polyacrylate. In terms of mass, the ratio of slaked lime, calcium carbonate and auxiliary agent is 400:80:20. Among the auxiliary agents, the mass ratio of cellulose, polyacrylamide and sodium polyacrylate is 8:2:2. The mass ratio of auxiliary agent to water is 20:140.

[0035] Comparative Example 1: The desulfurizer in the prior art is JY-409 type 5.1 mm gray cylindrical desulfurizer (Henan Juye Biotechnology Co., Ltd.).

[0036] The following examples and comparative examples were tested: (1) Radial strength test: refer to the standard "HG / T2782-2011 Determination of crushing resistance of fertilizer catalyst particles".

[0037] (2) Test of desulfurization effect: The experiment used sulfur dioxide standard gas with a sulfur dioxide content of 450-500 mg / m³, and used the SUV-100 flue gas analyzer produced by Shandong Xinze Instrument Co., Ltd.

[0038] Results and Analysis: Table 1 Radial strength test results of embodiments and comparative examples

[0039] Table 2 Desulfurization effect test of examples and comparative examples

[0040] The performance of the desulfurizer obtained can be adjusted by selecting the auxiliary agent of the present invention. For example, by adding cellulose, the desulfurization performance and strength of the desulfurizer can be improved. The desulfurizer obtained in the embodiment of the present invention has not only better strength but also better desulfurization effect than the comparative example.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A polymer-bonded calcium-based flue gas desulfurizer, characterized in that: The desulfurizer includes slaked lime, calcium carbonate and an auxiliary agent. The ratio of slaked lime, calcium carbonate and the auxiliary agent is (300 parts-450 parts) : (30 parts-120 parts) : (3 parts-30 parts) by mass.

2. The desulfurizing agent according to claim 1, characterized in that The slaked lime is slaked lime with a mass fraction of calcium hydroxide higher than 80%.

3. The desulfurizing agent according to claim 1, characterized in that The auxiliary agent includes one or more of clay, acrylic acid, sodium stearate, sodium polyacrylate, polyacrylamide, cellulose, sodium bicarbonate, magnesium oxide, carbide slag, kaolin, electrolytic manganese dioxide, iron oxide and alum.

4. The method for preparing a polymer-bonded calcium-based flue gas desulfurizer according to any one of claims 1 to 3, characterized in that: The preparation method comprises: S1: drying slaked lime and mixing the dried slaked lime with calcium carbonate; S2: mixing the mixed product in S1 with an auxiliary agent to obtain an intermediate product; S3: The intermediate product is stirred and kneaded with water, and dried to obtain a polymer-bonded calcium-based flue gas desulfurizer.

5. The preparation method according to claim 4, characterized in that: The drying temperature in S1 is 160°C-200°C, and the drying time is 1.5h-2.5h.

6. The preparation method according to claim 4, characterized in that: In terms of mass, the ratio of the auxiliary agent to water is (3 parts-30 parts):(110 parts-170 parts).

7. The preparation method according to claim 4, characterized in that: The drying temperature in S3 is 120°C-200°C, and the drying time is 20min-50min.

8. The preparation method according to claim 4, characterized in that: The polymer-bonded calcium-based flue gas desulfurizer is a cylindrical or four-leaf clover-shaped solid strip with a diameter of 4mm-7mm.

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