Slaked lime-containing adsorbent applied to flue gas purification and preparation method thereof
By combining high-purity hydrated lime with composite nano-adsorption particles and modified adsorption fibers, the problems of insufficient adsorbent purity and specific surface area in flue gas treatment are solved, achieving efficient flue gas purification and reuse under high-temperature conditions.
Patent Information
- Application Number
- CN202511069943.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-31
- Publication Date
- 2025-10-31
AI Technical Summary
In existing flue gas treatment technologies, the purity and specific surface area of adsorbents are insufficient, making it difficult to effectively adsorb complex flue gas components, especially heavy metals and dioxins. Furthermore, their performance deteriorates under high-temperature conditions, making them difficult to reuse.
Using high-purity slaked lime as a base, combined with potassium permanganate, carbide slag, diatomaceous earth, composite nano-adsorbent particles and modified adsorbent fibers, a high-purity adsorbent with a high specific surface area is prepared through processes such as acid decomposition, ultrasonic treatment, pulsed electric field and heating, thereby enhancing its high-temperature resistance and adsorption capacity.
The prepared adsorbent maintains high adsorption performance at high temperatures and can effectively capture complex components such as particulate matter, acidic gases and dioxins in flue gas. It has high adsorption efficiency and can be reused.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of adsorbent technology, specifically to an adsorbent containing slaked lime for flue gas purification and its preparation method. Background Technology
[0002] Current flue gas treatment technologies include dust removal, activated carbon adsorption, and catalytic oxidation. Adsorbent adsorption is a common technology, using raw materials such as activated carbon, molecular sieves, and macroporous adsorption resins. These materials have advantages such as high specific surface area, low cost, and fast adsorption-desorption rates. However, flue gas has a complex composition and requires efficient adsorption within a short time. Furthermore, as the adsorption process progresses, porous adsorbents are prone to having their adsorption sites covered by pollutants, affecting their adsorption performance. Some heavy metals, such as mercury, exist in multiple forms, including oxidized and particulate states, and are difficult to eliminate due to their volatility. The high temperature characteristics of flue gas can easily affect the performance of adsorbents, resulting in short lifespans and difficulty in reuse. Quicklime is also used as an adsorbent, but traditional quicklime has low purity (90-95%) and contains various impurities such as SiO2 and Fe2O3, leading to insufficient reactivity. Existing processes struggle to simultaneously achieve high purity (≥96%) and high specific surface area (≥40m²). 2 The existing process is insufficient to meet the requirements for high-quality hydrated lime (g). Summary of the Invention
[0003] To address the above problems, the present invention aims to provide an adsorbent containing slaked lime for flue gas purification and its preparation method.
[0004] The technical content of this invention is as follows:
[0005] This invention provides an adsorbent containing slaked lime for flue gas purification, comprising the following components by weight: 10-20 parts slaked lime, 5-10 parts potassium permanganate, 1-3 parts carbide slag, 1-3 parts diatomaceous earth, 7-10 parts composite nano-adsorbent particles, and 10-20 parts modified adsorbent fiber.
[0006] The composite nano-adsorbent particles are prepared by mixing biochar and activated carbon, adding ferric humate, grinding and mixing, then subjecting them to pulsed electric field treatment, and finally heating treatment.
[0007] The modified adsorption fiber is prepared by adding mercaptoacetic acid and alginate to graphite fiber and then reacting it under pressure and heat.
[0008] The adsorbent containing slaked lime comprises the following components by weight: 15 parts slaked lime, 8 parts potassium permanganate, 2 parts carbide slag, 2 parts diatomaceous earth, 8 parts composite nano-adsorbent particles, and 15 parts modified adsorbent fiber.
[0009] The preparation of the slaked lime involves immersing quicklime in an acid decomposition solution, ultrasonically treating it at 30-50 kHz for 20-30 minutes, and then performing gradient centrifugation purification by centrifuging at speeds of 2000-4000 rpm, 4000-6000 rpm, and 7000-9000 rpm for 1-3 minutes. The purified CaO is then mixed with ultrapure water at a solid-liquid ratio of 1:1-2 g / mL and pre-reacted at 40-60℃ for 25-35 minutes under nitrogen protection to generate nano-Ca(OH)2. The temperature is then gradient-increased at 1-2 MPa and 80-100℃ at a rate of 1-3℃ / min. Finally, 0.1-0.3 wt% of a modifier of nano-Ca(OH)2 is added, and the mixture is rapidly dehydrated under a vacuum of -0.06 MPa to -0.08 MPa.
[0010] The acid decomposition solution is citric acid in a volume ratio of 0.1:3-6 and dilute hydrochloric acid in a volume ratio of 0.1-0.5 mol / L; hydrochloric acid can dissolve encapsulated impurities (CaCO3, Fe2O3), and adding a trace amount of citric acid can decompose impurities that are difficult to dissolve in hydrochloric acid;
[0011] The modifier is sodium pyrophosphate and carboxymethyl cellulose in a mass ratio of 1-3:1. The hydroxyl groups in sodium pyrophosphate can undergo complexation reactions with insoluble salts, thus exhibiting dispersibility. Both carboxymethyl cellulose and pyrophosphate ions can combine with calcium hydroxide to form an electrostatic repulsion effect, improving the dispersibility of calcium hydroxide, reducing the rate of crystal nucleation, and thus refining the grains. The hydrogen bond donors it contains associate with sodium ions and other ions to reduce the effect on grain enlargement.
[0012] In the preparation of slaked lime in this invention, submicron-level impurities are targeted for removal. First, acid leaching is performed to dissolve encapsulated impurities (CaCO3, Fe2O3). Then, gradient low-temperature digestion and grain boundary reconstruction are used to generate nano-Ca(OH)2 crystal nuclei (D97≤34nm). Finally, grain boundary repair with a modifier is used to inhibit high-temperature grain growth through chemical bonding, thereby improving the high-temperature resistance of slaked lime. The resulting slaked lime has high purity and high specific surface area.
[0013] The specific preparation process of the composite nano-adsorption particles is as follows: biochar and activated carbon are mixed in a mass ratio of 10-15:3-4, ferric humate is added, and the mixture is ground in a ball mill for 10-20 min. After being treated in a pulsed electric field with a pulse power of 100-300V / cm for 3-6 min, the mixture is then heated at a temperature of 300-400℃ for 6-10 min to obtain the final product.
[0014] The amount of humic iron added is 10-14 wt% of the biochar.
[0015] Ferric humate can improve adsorption performance by chemically modifying the surface functional groups of activated carbon and biochar, such as hydroxyl groups. The energy of the pulsed electric field can act on the chemical bonds to promote the grafting reaction. Ferric humate introduces metal oxides, which undergo reduction reactions under the action of the electric field to form oxygen vacancies and nanoscale pores, thereby improving its mesopore volume and dispersibility. It can improve the adsorption capacity of substances such as dioxins and heavy metals. Heat treatment can increase the content of oxygen-containing groups on its surface.
[0016] The specific preparation process of the modified adsorption fiber is to add 6-10 wt% thioglycolic acid and 2-4 wt% alginate to graphite fiber and then homogenize and stir at a temperature of 60-70℃ and a pressure of 2-4 MPa for 60-80 min.
[0017] Mercaptoacetic acid and alginate can modify fibers. Alginate can form a microgel layer on the fiber surface. It contains polar groups such as hydroxyl and carboxyl groups, which have negative charge properties. It can electrostatically capture and adsorb positively charged particulate matter and heavy metals, and provide more reaction sites. The sulfhydryl and amino groups it contains can adsorb and capture acidic gases, and can improve the high temperature resistance of the fiber.
[0018] This invention also provides a method for preparing a quicklime-containing adsorbent for flue gas purification. The specific process involves mixing diatomaceous earth and carbide slag with potassium permanganate, followed by microwave heating to obtain mixture A; finally, quicklime, composite nano-adsorbent particles, and modified adsorbent fibers are added to mixture A and mixed to obtain mixture B; mixture B is then vacuum-dried to obtain the quicklime-containing adsorbent.
[0019] The microwave heating temperature is 60-80℃, and the heating time is 10-30 minutes.
[0020] The beneficial effects of this invention are as follows: This invention provides an adsorbent containing slaked lime for flue gas purification. The added slaked lime, prepared through processes such as acid decomposition and modification with modifiers, has high purity and high specific surface area, effectively adsorbing dust and reducing flue gas viscosity. The addition of composite nano-adsorbent particles with high mesopore content and highly reactive surface functional groups allows for the adsorption of particulate matter and organic compounds such as dioxins. The modified adsorbent fibers have more reactive groups, enabling them to capture acidic gases and other substances. The combination of these raw materials effectively adsorbs complex components in flue gas. This adsorbent exhibits high adsorption efficiency and strong high-temperature resistance, and can be applied to waste treatment such as flue gas purification.
[0021] This invention also provides a method for preparing a quicklime-containing adsorbent for flue gas purification. Potassium permanganate and solid particles such as diatomaceous earth are premixed and microwave-heated to promote the adsorption of the two to form a heterogeneous adsorption system. This method can reduce the impact of high temperature on potassium permanganate and improve the stability of the adsorbent material. Detailed Implementation
[0022] The present invention will be further described in detail below through specific implementation examples. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of protection of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art fall within the scope of the appended claims.
[0023] Unless otherwise specified, all raw materials and reagents used in this invention are from the conventional market.
[0024] Example 1
[0025] A method for preparing a quicklime-containing adsorbent for flue gas purification
[0026] Two parts of diatomaceous earth, two parts of carbide slag and eight parts of potassium permanganate were mixed and microwave-heated at 70°C for 20 minutes to obtain mixture A; finally, 15 parts of slaked lime, 9 parts of composite nano-adsorbent particles and 15 parts of modified adsorbent fiber were added to mixture A and mixed to obtain mixture B; mixture B was vacuum-dried to obtain an adsorbent containing slaked lime.
[0027] The preparation of the slaked lime involves immersing quicklime in an acid decomposition solution composed of citric acid and 0.3 mol / L dilute hydrochloric acid in a volume ratio of 0.1:5, ultrasonically treating it at 40 kHz for 25 minutes, and then performing gradient centrifugation purification by centrifuging at 3000 rpm, 5000 rpm, and 8000 rpm for 2 minutes sequentially. The purified CaO is then mixed with ultrapure water at a solid-liquid ratio of 1:1-2 g / mL and pre-reacted at 40-60℃ for 25-35 minutes under nitrogen protection to generate nano-Ca(OH)2. The temperature is then gradient-increased at 90℃ under a pressure of 1 MPa at a rate of 2℃ / min. Finally, a modifier composed of sodium pyrophosphate and carboxymethyl cellulose in a mass ratio of 2:1 is added at 0.2 wt% of the nano-Ca(OH)2, and the mixture is rapidly dehydrated under a vacuum of -0.07 MPa to obtain the final product.
[0028] The composite nano-adsorbent particles are obtained by mixing biochar and activated carbon in a mass ratio of 13:3, adding 12 wt% of ferric humate to the biochar, grinding in a ball mill for 15 min, treating in a pulsed electric field with a pulse power of 200 V / cm for 4 min, and then heating at a temperature of 350℃ for 8 min.
[0029] The modified adsorption fiber was obtained by adding 8 wt% thioglycolic acid and 3 wt% alginate to graphite fiber and then homogenizing and stirring at 65°C and 3 MPa for 70 min.
[0030] Example 2
[0031] A method for preparing a quicklime-containing adsorbent for flue gas purification
[0032] Mix 1 part diatomaceous earth, 1 part calcium carbide slag and 5 parts potassium permanganate and microwave heat at 60℃ for 10 min to obtain mixture A; finally add 10 parts slaked lime, 7 parts composite nano-adsorbent particles and 10 parts modified adsorbent fiber to mixture A and mix to obtain mixture B; vacuum decompression drying of mixture B to obtain adsorbent containing slaked lime.
[0033] The preparation of the slaked lime involves immersing quicklime in an acid decomposition solution composed of citric acid and dilute hydrochloric acid in a volume ratio of 0.1:3, ultrasonically treating it at 30 kHz for 20-30 minutes, and then purifying it by gradient centrifugation at 2000 rpm, 4000 rpm, and 8000 rpm for 2 minutes each. The purified CaO is mixed with ultrapure water at a solid-liquid ratio of 1:1 g / mL and pre-reacted at 50°C for 30 minutes under nitrogen protection to generate nano-Ca(OH)2. The temperature is then gradient-increased at 80°C at a pressure of 1 MPa at a rate of 1°C / min. Finally, a modifier composed of sodium pyrophosphate and carboxymethyl cellulose in a mass ratio of 1:1 is added to the nano-Ca(OH)2 and rapidly dehydrated under a vacuum of -0.06 MPa.
[0034] The composite nano-adsorbent particles are obtained by mixing biochar and activated carbon in a mass ratio of 10:3, adding 10 wt% of ferric humate to the biochar, grinding in a ball mill for 10 min, treating in a pulsed electric field with a pulse power of 100 V / cm for 3 min, and then heating at a temperature of 300℃ for 6 min.
[0035] The modified adsorption fiber was obtained by adding 6 wt% mercaptoacetic acid and 2 wt% alginate to graphite fiber and then homogenizing and stirring at 60°C and 2 MPa for 60 min.
[0036] Example 3
[0037] A method for preparing a quicklime-containing adsorbent for flue gas purification
[0038] Mix 3 parts diatomaceous earth, 3 parts calcium carbide slag and 10 parts potassium permanganate and microwave heat at 80℃ for 30 minutes to obtain mixture A; finally add 20 parts slaked lime, 10 parts composite nano-adsorbent particles and 20 parts modified adsorbent fiber to mixture A and mix to obtain mixture B; vacuum decompression drying of mixture B to obtain adsorbent containing slaked lime.
[0039] The preparation of the slaked lime involves immersing quicklime in an acid decomposition solution composed of citric acid and 0.5 mol / L dilute hydrochloric acid in a volume ratio of 0.1:6, ultrasonically treating it at 50 kHz for 30 minutes, and then performing gradient centrifugation purification by centrifuging at 4000 rpm, 6000 rpm, and 9000 rpm for 3 minutes sequentially. The purified CaO is then mixed with ultrapure water at a solid-liquid ratio of 1:2 g / mL and pre-reacted at 60℃ for 35 minutes under nitrogen protection to generate nano-Ca(OH)2. The temperature is then gradient-increased at 100℃ under a pressure of 2 MPa at a rate of 3℃ / min. Finally, a modifier composed of sodium pyrophosphate and carboxymethyl cellulose in a mass ratio of 3:1 is added at 0.3 wt% of the nano-Ca(OH)2, and the mixture is rapidly dehydrated under a vacuum of -0.08 MPa to obtain the final product.
[0040] The composite nano-adsorbent particles are obtained by mixing biochar and activated carbon in a mass ratio of 15:4, adding 14 wt% of iron humate to the biochar, grinding in a ball mill for 20 min, treating in a pulsed electric field with a pulse power of 300 V / cm for 6 min, and then heating at a temperature of 400℃ for 10 min.
[0041] The modified adsorption fiber was obtained by adding 10 wt% thioglycolic acid and 4 wt% alginate to graphite fiber and then homogenizing and stirring at 70°C and 4 MPa for 80 min.
[0042] Example 4
[0043] A method for preparing a quicklime-containing adsorbent for flue gas purification
[0044] Mix 1 part diatomaceous earth, 3 parts calcium carbide slag and 6 parts potassium permanganate and microwave heat at 70℃ for 10 minutes to obtain mixture A; finally add 12 parts slaked lime, 8 parts composite nano-adsorbent particles and 12 parts modified adsorbent fiber to mixture A and mix to obtain mixture B; vacuum decompression drying of mixture B to obtain adsorbent containing slaked lime.
[0045] The preparation of the slaked lime involves immersing quicklime in an acid decomposition solution composed of citric acid and 0.2 mol / L dilute hydrochloric acid in a volume ratio of 0.1:4, ultrasonically treating it at 35 kHz for 25 minutes, and then performing gradient centrifugation purification by centrifuging at 2000 rpm, 6000 rpm, and 7000 rpm for 2 minutes sequentially. The purified CaO is then mixed with ultrapure water at a solid-liquid ratio of 1:1 g / mL and pre-reacted at 50°C for 25 minutes under nitrogen protection to generate nano-Ca(OH)2. The temperature is then gradient-increased at 100°C at a pressure of 1 MPa and a heating rate of 1°C / min. Finally, a modifier composed of sodium pyrophosphate and carboxymethyl cellulose in a mass ratio of 1:1 is added at 0.3 wt% of the nano-Ca(OH)2, and the mixture is rapidly dehydrated under a vacuum of -0.08 MPa to obtain the final product.
[0046] The composite nano-adsorbent particles are obtained by mixing biochar and activated carbon in a mass ratio of 11:3, adding 11 wt% of ferric humate to the biochar, grinding in a ball mill for 10 min, treating in a pulsed electric field with a pulse power of 200 V / cm for 4 min, and then heating at 300℃ for 10 min.
[0047] The modified adsorption fiber was obtained by adding 7 wt% mercaptoacetic acid and 2 wt% alginate to graphite fiber and then homogenizing and stirring at 70°C and 2 MPa for 80 min.
[0048] Example 5
[0049] A method for preparing a quicklime-containing adsorbent for flue gas purification
[0050] Mix 3 parts diatomaceous earth, 1 part calcium carbide slag and 9 parts potassium permanganate and microwave heat at 60℃ for 15 minutes to obtain mixture A; finally add 18 parts slaked lime, 9 parts composite nano-adsorbent particles and 18 parts modified adsorbent fiber to mixture A and mix to obtain mixture B; vacuum decompression drying of mixture B to obtain adsorbent containing slaked lime.
[0051] The preparation of the slaked lime involves immersing quicklime in an acid decomposition solution composed of citric acid and 0.4 mol / L dilute hydrochloric acid in a volume ratio of 0.1:5, ultrasonically treating it at 45 kHz for 25 minutes, and then performing gradient centrifugation purification by centrifuging at 4000 rpm, 4000 rpm, and 9000 rpm for 2 minutes sequentially. The purified CaO is mixed with ultrapure water at a solid-liquid ratio of 1:1 g / mL and pre-reacted at 50°C for 30 minutes under nitrogen protection to generate nano-Ca(OH)2. The temperature is then gradient-increased at 90°C under a pressure of 2 MPa at a rate of 3°C / min. Finally, a modifier composed of sodium pyrophosphate and carboxymethyl cellulose in a mass ratio of 3:1 is added at 0.1 wt% of the nano-Ca(OH)2, and the mixture is rapidly dehydrated under a vacuum of -0.06 MPa to obtain the final product.
[0052] The composite nano-adsorbent particles are obtained by mixing biochar and activated carbon in a mass ratio of 14:4, adding 13wt% of ferric humate to the biochar, grinding in a ball mill for 15 minutes, treating in a pulsed electric field with a pulse power of 300V / cm for 6 minutes, and then heating at a temperature of 400℃ for 6 minutes.
[0053] The modified adsorption fiber was obtained by adding 9 wt% thioglycolic acid and 4 wt% alginate to graphite fiber and then homogenizing and stirring at 70°C and 2 MPa for 80 min.
[0054] Comparative Example 1
[0055] The difference between Comparative Example 1 and Example 1 is that the slaked lime in Comparative Example 1 was replaced with commercially available slaked lime, while everything else remained the same.
[0056] Comparative Example 2
[0057] The difference between Comparative Example 2 and Example 1 is that the composite nano-adsorbent particles of Comparative Example 2 are prepared by mixing biochar and activated carbon in a mass ratio of 13:3 and then grinding them in a ball mill for 15 minutes, while other processes remain the same.
[0058] Comparative Example 3
[0059] The difference between Comparative Example 3 and Example 1 is that the modified adsorption fiber in Comparative Example 3 is replaced with an equal amount of graphite fiber, while everything else remains the same.
[0060] Comparative Example 4
[0061] The difference between Comparative Example 4 and Example 1 is that potassium permanganate was not added in Comparative Example 4, but everything else remained the same.
[0062] Comparative Example 5
[0063] The difference between Comparative Example 5 and Example 1 is that the adsorbent in Comparative Example 5 is prepared by mixing all raw materials, while other aspects remain the same.
[0064] I. The performance of the hydrated lime in Example 1 and the comparative example was tested, and the test results are shown in Table 1.
[0065] Table 1 Properties of hydrated lime
[0066]
[0067]
[0068] As shown in Table 1, the hydrated lime prepared by this invention has high purity, large specific surface area, strong anti-sintering properties, and large pore volume and fine particle size.
[0069] 2. The charge properties of the slaked lime in Example 1 and Comparative Example 1, as well as the modified adsorption fiber prepared in Example 1 and the unmodified adsorption fiber in Comparative Example 3, were tested. The test results are shown in Table 2.
[0070] Table 2 Charge properties of raw materials
[0071]
[0072] As shown in Table 2, Comparative Example 1 shows that the modifier added during the preparation of slaked lime in this invention treats the crystallization of slaked lime, promotes the strong electronegativity of the calcium hydroxide surface, and improves the dispersibility of slaked lime; Comparative Example 3 shows that this invention modifies the adsorption fiber, introduces polar groups to change the charge properties of the fiber surface, and improves the adsorption performance of the fiber.
[0073] 2. 100g of the adsorbents prepared in the examples and comparative examples were placed in fixed-bed adsorption tubes, respectively. N2 was simulated flue gas, the gas flow rate was 1.2L / min, and the reaction temperatures were controlled at 150℃, 300℃, and 450℃, respectively. The ignition properties of the two adsorbents were tested, and the test results are shown in Table 3.
[0074] Table 3 Ignition performance of the adsorbent
[0075]
[0076]
[0077] Table 3 shows that the adsorbent prepared by this invention has high ignition performance, with a retention rate of >90% at >450℃, making it suitable for use under high-temperature conditions. Comparative Example 1 shows that the slaked lime prepared by this invention has lower impurity content and better ignition performance compared to ordinary slaked lime. Comparative Example 2 shows that the addition of composite nano-adsorbent particles to the activated carbon and biochar improves their ignition performance. Comparative Example 3 shows that the modified adsorbent fiber added by this invention improves the structural strength of the material through thiol modification, thereby improving its ignition performance. Comparative Example 4 shows that the premixing of potassium permanganate with diatomaceous earth and other raw materials and microwave heating can improve the thermal stability of the adsorbent material.
[0078] 3. The adsorbents prepared in the examples and comparative examples were applied to the adsorption treatment of incineration flue gas in a waste treatment plant. The content of substances in the flue gas before and after adsorption was detected. The adsorption time was 3 hours, and the adsorption efficiency was obtained. The test results are shown in Table 4. After the adsorbent was reused 20 times, the adsorption efficiency of substances is shown in Table 5.
[0079] Table 4 Adsorption efficiency of substances in flue gas
[0080]
[0081]
[0082] Table 4 Adsorption efficiency of substances in flue gas
[0083]
[0084] Table 4 shows that the quicklime adsorbent prepared by this invention can significantly reduce the content of harmful substances in flue gas, and has high adsorption capacity for particulate matter, dioxins, acid gases, organic pollutants, and heavy metals. Table 5 shows that the adsorbent prepared by this invention has high adsorption stability, can be reused, and its adsorption efficiency is still higher than 90% after 20 uses. In Table 4, Comparative Example 1 shows that the quicklime of this invention has significantly better adsorption performance than ordinary quicklime on the market. The adsorbent of Comparative Example 2 has a lower adsorption efficiency for substances such as dioxins and particulate matter compared with the examples, indicating that the chemical optimization of surface groups and physical optimization of mesoporous structure of the composite nano-adsorbent particles of this invention can significantly improve the adsorption of dioxins and particulate matter. Comparative Example 3 shows that the modified fiber of this invention can reduce particulate matter and acid gases by improving the negative charge distribution of the surface and improving the adsorption and trapping sites by grafting amino groups.
[0085] The content of toxic gases and other substances; as shown in Comparative Example 4, high manganese content is reduced during the preparation of the adsorbent.
[0086] Potassium sulfate is fixed on solid particles, enhancing the oxidation properties of the particle surface and enabling the adsorption of pollutants.
[0087] It oxidizes and decomposes pollutants, thereby improving adsorption performance.
Claims
1. An adsorbent containing slaked lime for use in flue gas purification, characterized in that, It contains the following components by weight: 10-20 parts hydrated lime, 5-10 parts potassium permanganate, 1-3 parts carbide slag, 1-3 parts diatomaceous earth, 7-10 parts composite nano-adsorption particles, and 10-20 parts modified adsorption fiber. The composite nano-adsorbent particles are prepared by mixing biochar and activated carbon, adding ferric humate, grinding and mixing, then subjecting them to pulsed electric field treatment, and finally heating treatment. The modified adsorption fiber is prepared by adding thiol acetic acid and alginate to graphite fiber and then reacting it under pressure and heat.
2. The adsorbent containing slaked lime for flue gas purification according to claim 1, characterized in that, It contains the following components by weight: 15 parts hydrated lime, 8 parts potassium permanganate, 2 parts carbide slag, 2 parts diatomaceous earth, 8 parts composite nano-adsorption particles, and 15 parts modified adsorption fiber.
3. The adsorbent containing slaked lime for flue gas purification according to claim 1, characterized in that, The preparation of the slaked lime involves immersing quicklime in an acid decomposition solution, ultrasonically treating it at 30-50 kHz for 20-30 minutes, and then performing gradient centrifugation purification by centrifuging at speeds of 2000-4000 rpm, 4000-6000 rpm, and 7000-9000 rpm for 1-3 minutes. The purified CaO is then mixed with ultrapure water at a solid-liquid ratio of 1:1-2 g / mL and pre-reacted at 40-60℃ for 25-35 minutes under nitrogen protection to generate nano-Ca(OH)2. The temperature is then gradient-increased at 1-2 MPa and 80-100℃ at a rate of 1-3℃ / min. Finally, 0.1-0.3 wt% of a modifier of nano-Ca(OH)2 is added, and the mixture is rapidly dehydrated under a vacuum of -0.06 MPa to -0.08 MPa.
4. The adsorbent containing slaked lime for flue gas purification according to claim 3, characterized in that, The acid decomposition solution is citric acid in a volume ratio of 0.1:3-6 and dilute hydrochloric acid in a volume ratio of 0.1-0.5 mol / L.
5. The adsorbent containing slaked lime for flue gas purification according to claim 3, characterized in that, The modifier is sodium pyrophosphate and carboxymethyl cellulose in a mass ratio of 1-3:
1.
6. The adsorbent containing slaked lime for flue gas purification according to claim 1, characterized in that, The specific preparation process of the composite nano-adsorbent particles is as follows: biochar and activated carbon are mixed in a mass ratio of 10-15:3-4, ferric humate is added, and the mixture is ground in a ball mill for 10-20 min. After being treated in a pulsed electric field with a pulse power of 100-300V / cm for 3-6 min, the mixture is then heated at a temperature of 300-400℃ for 6-10 min.
7. The adsorbent containing slaked lime for flue gas purification according to claim 6, characterized in that, The amount of ferric humate added is 10-14 wt% of the biochar.
8. The quicklime-containing adsorbent for flue gas purification according to claim 1, characterized in that, The specific preparation process of the modified adsorption fiber is to add 6-10 wt% thioglycolic acid and 2-4 wt% alginate to graphite fiber and then homogenize and stir at a temperature of 60-70℃ and a pressure of 2-4 MPa for 60-80 min.
9. A method for preparing a quicklime-containing adsorbent for flue gas purification, used to prepare the quicklime-containing adsorbent as described in any one of claims 1-8, characterized in that, The preparation method includes: adding diatomaceous earth and carbide slag to potassium permanganate, mixing and then heating with microwave to obtain mixture A; adding slaked lime, composite nano-adsorbent particles and modified adsorbent fibers to mixture A and mixing to obtain mixture B; and drying mixture B under vacuum to obtain an adsorbent containing slaked lime.
10. A method for preparing a quicklime-containing adsorbent for flue gas purification according to claim 9, characterized in that, The microwave heating temperature is 60-80℃, and the heating time is 10-30 minutes.