A cement deamination agent and preparation method thereof

Abstract

The present application relates to the technical field of waste gas treatment, and in particular to a cement deamination agent and a preparation method thereof; a cement deamination agent comprises the following raw material components in parts by weight: 20-30 parts of a low eutectic solvent, 10-20 parts of chitosan and 5-10 parts of a regenerated fiber hydrogel; wherein the low eutectic solvent comprises choline chloride, phenol and ethylene glycol; the molar ratio of the choline chloride, phenol and ethylene glycol is 1:(2-15):(1-8); the present application discloses a cement deamination agent and a preparation method thereof, and the prepared cement deamination agent can efficiently remove ammonia in cement production; the deamination agent is not only simple to prepare and low in cost, but also produces no harmful substances during use, and meets environmental protection requirements. At the same time, its excellent ammonia absorption performance can significantly improve the environmental protection level of cement production.

Description

Technical Field

[0001] The present application relates to the technical field of waste gas treatment, and in particular to a cement deammoniation agent and a preparation method thereof. Background Art

[0002] As most existing cement companies use low-nitrogen combustion and SNCR denitrification, as well as SNCR combined with SCR denitrification, in order to meet the nitrogen oxide emission standards, most cement companies adopt the method of increasing the SNCR ammonia injection amount on the basis of the staged combustion transformation of the decomposition furnace to control nitrogen oxide emissions, which usually leads to serious ammonia escape and waste of ammonia resources; therefore, the recovery and comprehensive utilization of escaped ammonia has important environmental benefits.

[0003] The ammonia pollution problem generated in the current cement production process is becoming increasingly prominent, and the ammonia generated in the production process needs to be removed. Traditional ammonia removal methods have disadvantages such as low efficiency, high cost, and environmental unfriendliness. Currently, commonly used deammonification methods mainly include physical adsorption and chemical absorption. The physical adsorption method is limited by the capacity and regeneration problems of the adsorbent, while the chemical absorption method may involve the use and disposal of harmful chemicals.

[0004] Therefore, the development of an efficient, environmentally friendly and low-cost deammonification technology has become an urgent need in the cement industry. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present application provides a cement deamination agent and a preparation method thereof, which can efficiently remove ammonia generated in cement production, is environmentally friendly and has low cost.

[0006] In the first aspect, the present application provides a cement deamination agent, which adopts the following technical solution:

[0007] A cement deammoniation agent comprises the following raw material components in parts by mass: 20-30 parts of a low eutectic solvent, 10-20 parts of chitosan and 5-10 parts of a regenerated fiber hydrogel.

[0008] Preferably, the low eutectic solvent comprises choline chloride, phenol and ethylene glycol; the molar ratio of choline chloride, phenol and ethylene glycol is 1:(2-15):(1-8);

[0009] Preferably, the molar ratio of choline chloride, phenol and ethylene glycol is 1:(5-9):(2-6).

[0010] More preferably, the molar ratio of choline chloride, phenol and ethylene glycol is 1:2:4, 1:5:4, 1:9:4, 1:15:4, 1:7:1, 1:7:2, 1:7:6, 1:7:8 or 1:7:4.

[0011] More preferably, the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:4.

[0012] By adopting the above technical scheme, in the present application, the raw materials of the cement deamination agent are improved, and a ternary low eutectic solvent obtained by mixing choline chloride, phenol and ethylene glycol is added. The added choline chloride acts as a hydrogen bond acceptor, which helps to form a stable low eutectic solvent and reduce the volatilization of ethylene glycol; the added phenol and ethylene glycol act as hydrogen bond donors, which can efficiently absorb ammonia; the weak acidity of phenol makes its binding ability with ammonia stronger than ordinary hydrogen bonds, thereby achieving efficient and reversible ammonia absorption; the introduction of ethylene glycol increases the absorption sites and reduces the solvent viscosity; in the present application, the removal effect of the cement deamination agent is effectively improved through the synergistic effect between choline chloride, phenol and ethylene glycol.

[0013] In the present application, the raw materials of cement deammoniation agent are improved, chitosan and regenerated fiber hydrogel are added, and the added chitosan and regenerated fiber hydrogel are mixed to prepare regenerated cellulose / chitosan aerogel material. The prepared regenerated cellulose / chitosan aerogel material has a three-dimensional porous structure and has high adsorption efficiency, and can efficiently adsorb ammonia.

[0014] In the present application, a ternary low eutectic solvent composed of choline chloride, phenol and ethylene glycol is mixed with a regenerated cellulose / chitosan aerogel material. Through the synergistic effect between the ternary low eutectic solvent and the regenerated cellulose / chitosan aerogel material, a deamination agent with high adsorption performance can be obtained, which effectively improves the removal of ammonia.

[0015] Preferably, chitosan is modified by the following steps: chitosan and acetic acid are mixed, and then glutaraldehyde is added to react to obtain cross-linked modified chitosan.

[0016] Preferably, the mass ratio of chitosan to acetic acid is (1-4):(5-10), and the mass volume ratio of chitosan to glutaraldehyde is 1 g:(1-2) ml.

[0017] By adopting the above technical solution, the adsorption performance of chitosan can be effectively improved by modifying chitosan in the present application, and the modified chitosan can be evenly mixed with regenerated cellulose to obtain a regenerated cellulose / chitosan aerogel material with high adsorption performance.

[0018] In a second aspect, the present application provides a method for preparing a cement deamination agent, using the following technical solution:

[0019] A method for preparing a cement deamination agent comprises the following steps:

[0020] Weigh each raw material according to the formula;

[0021] The chitosan is mixed with the regenerated fiber hydrogel, and then a low eutectic solvent is added for mixing to obtain a cement deammoniation agent.

[0022] Preferably, the mixing temperature is 40-80°C.

[0023] More preferably, the mixing temperature is 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C or 80°C.

[0024] In a third aspect, the present application provides a use of the above-mentioned cement deamination agent or the cement deamination agent prepared by the above-mentioned method in removing ammonia, using the following technical solution:

[0025] Application of the cement deamination agent or the cement deamination agent prepared by the method in removing ammonia.

[0026] Preferably, the step of removing ammonia by cement deamination agent is as follows: spraying cement deamination agent into the flue gas containing ammonia escape, and removing ammonia in the flue gas.

[0027] Preferably, the amount of flue gas containing ammonia escape is 150000-250000m 3 / h.

[0028] Preferably, the amount of flue gas containing ammonia escape is 150000m 3 / h、160000m 3 / h、170000m 3 / h、180000m 3 / h、190000m 3 / h、200000m 3 / h、210000m 3 / h、220000m 3 / h、230000m 3 / h、240000m 3 / h、250000m 3 / h.

[0029] More preferably, the amount of flue gas containing ammonia escape is 200000m 3 / h.

[0030] Preferably, the injection amount of the cement deamination agent is 200-400kg / h; preferably, the injection amount of the cement deamination agent is 200kg / h, 250kg / h, 300kg / h, 350kg / h or 400kg / h.

[0031] More preferably, the injection rate of the cement deammoniation agent is 300 kg / h.

[0032] In a specific feasible implementation plan, during the cement production process, the flue gas generated contains ammonia. In order to remove the ammonia in the flue gas, the steps are as follows: spray the cement deamination agent directly into the flue after the high-temperature fan outlet, and remove the ammonia in the flue gas. A multi-stage spray gun is inserted in the flue to ensure sufficient mixing of the cement deamination agent and the flue gas.

[0033] By adopting the above technical solution, in this application, ammonia is removed by spraying cement deamination agent into the flue gas duct; before spraying cement deamination agent, the ammonia escape concentration is 60mg / Nm 3 After the cement denitrification agent is sprayed, the SNCR denitrification ammonia escape concentration is less than 8mg / m 3 、SCR denitrification ammonia escape concentration is less than 5mg / m 3 .

[0034] In summary, the present application includes at least one of the following beneficial technical effects:

[0035] The present application discloses a cement deamination agent. Through the synergistic effect of a low eutectic solvent, chitosan and regenerated fiber hydrogel, a cement deamination agent with high adsorption performance can be prepared. After the cement deamination agent is sprayed into the flue gas duct, the SNCR denitrification ammonia escape concentration is less than 8 mg / m 3 、SCR denitrification ammonia escape concentration is less than 5mg / m 3 , achieving efficient removal of ammonia in cement production;

[0036] The present application discloses a method for preparing a cement deammoniation agent, which is simple to prepare and low in cost, and does not produce any harmful substances during use, thus meeting environmental protection requirements. At the same time, its excellent ammonia absorption performance can significantly improve the environmental protection level of cement production. DETAILED DESCRIPTION

[0037] The technical solution of the present application is further illustrated by specific embodiments below. The specific embodiments do not limit the protection scope of the present application; some non-essential modifications and adjustments made by others based on the concept of the present application still fall within the protection scope of the present application.

[0038] The raw materials involved in this application are all commercially available products, and the application is further described in detail below in conjunction with the embodiments and comparative examples.

[0039] Source of raw materials:

[0040] Preparation of regenerated cellulose hydrogel:

[0041] 1.5 g of cotton pulp (DP=560) was added to ascorbic acid to obtain a mixed solution containing 2 wt % of cotton pulp;

[0042] 100 g of NMMO·H20 solution was added and mixed, and mechanically stirred for 20 min at 100°C and -0.1 MPa vacuum conditions to obtain a cellulose / NMMO mixed solution. After the cellulose / NMMO mixed solution changed from turbid to uniform transparent amber, the solution was poured into a mold and solidified at room temperature. The completely solidified cellulose material was placed in deionized water and soaked for 72 h. The water was changed every 12 h to remove the solidified NMMO to obtain a white regenerated cellulose hydrogel.

[0043] Embodiment 1:

[0044] A method for preparing a cement deamination agent comprises the following steps:

[0045] Step 1: Preparation of low eutectic solvent:

[0046] Weigh 139.63 g of choline chloride, 658.777 g of phenol and 248.272 g of ethylene glycol, i.e., the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:4;

[0047] Choline chloride, phenol and ethylene glycol were mixed and stirred at 60°C for 30 minutes to obtain a homogeneous clear and transparent solution, thereby obtaining a low eutectic solvent;

[0048] Step 2: Preparation of cement deamination agent:

[0049] (1) Weigh the raw materials according to the formula: 25 kg of deep eutectic solvent, 15 kg of chitosan and 8 kg of regenerated fiber hydrogel;

[0050] (2) Chitosan powder was dissolved in acetic acid (1 wt%) solution, stirred thoroughly at 25°C, regenerated fiber hydrogel was added, and stirred for 30 min using a high-speed mechanical shearing machine at 15,000 r / min. After stirring evenly, vacuum degassing was performed; the mixed solution was then frozen in a refrigerator for 12 h, and freeze-dried at -55°C in a vacuum environment for 48 h to obtain a regenerated cellulose / chitosan aerogel material; a low eutectic solvent was then added and mixed and stirred for 30 min to obtain a cement deamination agent.

[0051] Embodiment 2:

[0052] The difference from Example 1 is that when preparing the low eutectic solvent, the added amounts of choline chloride, phenol and ethylene glycol are different.

[0053] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 188.222 g of phenol and 248.272 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:2:4.

[0054] Embodiment 3:

[0055] The difference from Example 1 is that when preparing the low eutectic solvent, the added amounts of choline chloride, phenol and ethylene glycol are different.

[0056] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 470.555 g of phenol and 248.272 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:5:4.

[0057] Embodiment 4:

[0058] The difference from Example 1 is that when preparing the low eutectic solvent, the added amounts of choline chloride, phenol and ethylene glycol are different.

[0059] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 846.999 g of phenol and 248.272 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:9:4.

[0060] Embodiment 5:

[0061] The difference from Example 1 is that when preparing the low eutectic solvent, the added amounts of choline chloride, phenol and ethylene glycol are different.

[0062] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 1411.665 g of phenol and 248.272 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:15:4.

[0063] Embodiment 6:

[0064] The difference from Example 1 is that when preparing the low eutectic solvent, the added amounts of choline chloride, phenol and ethylene glycol are different.

[0065] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 658.777 g of phenol and 62.068 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:1.

[0066] Embodiment 7:

[0067] The difference from Example 1 is that when preparing the low eutectic solvent, the added amounts of choline chloride, phenol and ethylene glycol are different.

[0068] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 658.777 g of phenol and 124.136 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:2.

[0069] Embodiment 8:

[0070] The difference from Example 1 is that when preparing the low eutectic solvent, the added amounts of choline chloride, phenol and ethylene glycol are different.

[0071] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 658.777 g of phenol and 372.408 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:6.

[0072] Embodiment 9:

[0073] The difference from Example 1 is that when preparing the low eutectic solvent, the added amounts of choline chloride, phenol and ethylene glycol are different.

[0074] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 658.777 g of phenol and 496.544 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:8.

[0075] Embodiment 10:

[0076] The difference from Example 1 is that when preparing the low eutectic solvent, the temperature for adding choline chloride, phenol and ethylene glycol and mixing them is 40°C.

[0077] Embodiment 11:

[0078] The difference from Example 1 is that when preparing the low eutectic solvent, the temperature for adding choline chloride, phenol and ethylene glycol for mixing is 80°C.

[0079] Embodiment 12:

[0080] The difference from Example 1 is that the chitosan is modified chitosan.

[0081] The steps of modifying chitosan are as follows:

[0082] 100 g of chitosan was added to 500 g of acetic acid (volume concentration 2%) and stirred, 200 ml of glutaraldehyde (volume concentration 25%) was added for reaction, and the mixture was placed in a microwave reactor. The mixture was heated to 35° C. at a speed of 300 rpm under a microwave radiation power of 300 W and stirred for 1 h. The mixture was naturally cooled, filtered and washed several times, and vacuum dried at 50° C. for 24 h to obtain cross-linked modified chitosan.

[0083] Embodiment 13:

[0084] The difference from Example 1 is that the chitosan is modified chitosan.

[0085] The steps of modifying chitosan are as follows:

[0086] 250 g of chitosan was added to 700 g of acetic acid (volume concentration 2%) and stirred, 500 ml of glutaraldehyde (volume concentration 25%) was added for reaction, and the mixture was placed in a microwave reactor. The mixture was heated to 35° C. at a speed of 300 rpm under a microwave radiation power of 300 W and stirred for 1 h. The mixture was naturally cooled, filtered and washed several times, and vacuum dried at 50° C. for 24 h to obtain cross-linked modified chitosan.

[0087] Embodiment 14:

[0088] The difference from Example 1 is that the chitosan is modified chitosan.

[0089] The steps of modifying chitosan are as follows:

[0090] 400 g of chitosan was added to 1000 g of acetic acid (volume concentration 2%) and stirred, 800 ml of glutaraldehyde (volume concentration 25%) was added for reaction, and the mixture was placed in a microwave reactor. The mixture was heated to 35° C. at a speed of 300 rpm under a microwave radiation power of 300 W and stirred for 1 h. The mixture was naturally cooled, filtered and washed several times, and vacuum dried at 50° C. for 24 h to obtain cross-linked modified chitosan.

[0091] Embodiment 15:

[0092] The difference from Example 13 is that when the cement deamination agent is prepared, the added amounts of the low eutectic solvent, chitosan and regenerated fiber hydrogel are different.

[0093] A cement deammoniation agent comprises the following raw material components in parts by mass: 20 kg of a low eutectic solvent, 10 kg of chitosan and 5 kg of a regenerated fiber hydrogel.

[0094] Embodiment 16:

[0095] The difference from Example 13 is that when the cement deamination agent is prepared, the added amounts of the low eutectic solvent, chitosan and regenerated fiber hydrogel are different.

[0096] A cement deammoniation agent comprises the following raw material components in parts by mass: 30 kg of a low eutectic solvent, 20 kg of chitosan and 10 kg of a regenerated fiber hydrogel.

[0097] Comparative Example 1:

[0098] The difference from Example 1 is that when preparing the low eutectic solvent, the raw materials of the low eutectic solvent are different.

[0099] A cement deammoniation agent comprises the following raw materials: 658.777 g of phenol and 248.272 g of ethylene glycol.

[0100] Comparative Example 2:

[0101] The difference from Example 1 is that when preparing the low eutectic solvent, the raw materials of the low eutectic solvent are different.

[0102] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride and 248.272 g of ethylene glycol.

[0103] Comparative Example 3:

[0104] The difference from Example 1 is that when preparing the low eutectic solvent, the raw materials of the low eutectic solvent are different.

[0105] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 94.111 g of phenol and 248.272 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:1:4.

[0106] Comparative Example 4:

[0107] The difference from Example 1 is that when preparing the low eutectic solvent, the raw materials of the low eutectic solvent are different.

[0108] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 1505.776 g of phenol and 248.272 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:16:4.

[0109] Comparative Example 5:

[0110] The difference from Example 1 is that when preparing the low eutectic solvent, the raw materials of the low eutectic solvent are different.

[0111] A cement deammoniation agent comprises the following raw materials: 139.63 g of choline chloride, 658.777 g of phenol and 558.612 g of ethylene glycol, that is, the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:9.

[0112] Comparative Example 6:

[0113] The difference from Example 1 is that when preparing the low eutectic solvent, the temperature of mixing choline chloride, phenol and ethylene glycol is 35°C.

[0114] Comparative Example 7:

[0115] The difference from Example 1 is that when preparing the low eutectic solvent, the temperature of mixing choline chloride, phenol and ethylene glycol is 85°C.

[0116] Performance test 1:

[0117] The cement deamination agent prepared above was used in a cement production plant (cement kiln adopts SNCR denitrification) to remove ammonia generated in the cement production process. Without treatment, the flue gas volume during the flue gas emission process was 200000m 3 / h, flue gas composition (volume percentage): hydrogen 51.8%, nitrogen 19.3%, ammonia 6.5%, argon 3.6%, methane 18.8%, exhaust temperature 110℃, ammonia escape concentration 60mg / Nm 3 The products prepared in the above embodiments and comparative examples are used to remove ammonia from flue gas, and the ammonia removal capacity is tested. The specific steps are as follows: the cement deamination agent is directly sprayed into the flue after the high-temperature fan outlet to remove ammonia from the flue gas. The injection amount of the cement deamination agent is 300 kg / h. After treatment, the working flue gas volume is 20000 m 3 / h, the exhaust gas temperature drops below 95℃.

[0118] The ammonia escape concentration of the treated flue gas was tested, and the test results are as follows: the ammonia escape standard is 8 mg / m 3 (10ppm).

[0119] Table 1 Ammonia removal results of cement deamination agent

[0120] <![CDATA[Ammonia slip concentration (mg / Nm 3 )]]> Example 1 3 Example 2 6 Example 3 4 Example 4 4 Example 5 6 Example 6 7 Example 7 5 Example 8 5 Example 9 7 Example 10 6 Embodiment 11 6 Example 12 2 Embodiment 13 1 Embodiment 14 2 Embodiment 15 1.5 Example 16 1.5 Comparative Example 1 35 Comparative Example 2 40 Comparative Example 3 15 Comparative Example 4 18 Comparative Example 5 17 Comparative Example 6 12 Comparative Example 7 13

[0121] It can be seen from Table 1 that the cement deamination agent prepared by the method of the present application is used to remove ammonia in the flue gas. After the cement deamination agent removes ammonia in the flue gas, the ammonia escape concentration is less than 8 mg / Nm 3 .

[0122] Combined with the test results of Example 1 to Example 5, it can be seen that the amount of phenol added has an impact on the removal effect of the prepared cement deamination agent. When the molar ratio of choline chloride, phenol and ethylene glycol is 1: (2-15): 4, the prepared cement deamination agents all meet the standards; and when the molar ratio of choline chloride, phenol and ethylene glycol is 1: (5-9): 4, the removal effect of the prepared cement deamination agent is the best; It indicates that the synergistic effect between the added choline chloride, phenol and ethylene glycol effectively improves the removal effect of the cement deamination agent.

[0123] Combined with the test results of Example 1 and Examples 6-9, it can be seen that the amount of ethylene glycol added has an impact on the removal effect of the prepared cement deamination agent. When the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:(1-8), the prepared cement deamination agents all meet the standards; when the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:(2-6), the removal effect of the cement deamination agent is best; it shows that the synergistic effect between the added choline chloride, phenol and ethylene glycol effectively improves the removal effect of the cement deamination agent.

[0124] Combined with the test results of Example 1, Example 10 and Example 11, it can be seen that when the mixing temperature of choline chloride, phenol and ethylene glycol is 40-80°C, the prepared cement deamination agents all meet the standards, and when the mixing temperature is 60°C, the removal effect of the cement deamination agent is the best.

[0125] Combining the test results of Example 1 and Comparative Example 1, it can be seen that the removal effect of Example 1 is better than that of Comparative Example 1, indicating that the added choline chloride, as a hydrogen bond acceptor, helps to form a stable low eutectic solvent and reduce the volatilization of ethylene glycol, further indicating that the synergistic effect between the added choline chloride, phenol and ethylene glycol effectively improves the removal effect of the cement deamination agent.

[0126] Combining the test results of Example 1 and Comparative Example 2, it can be seen that the removal effect of Example 1 is better than that of Comparative Example 2, indicating that the added phenol is weakly acidic, so that its binding ability with ammonia is stronger than ordinary hydrogen bonding, thereby achieving efficient and reversible ammonia absorption; the added phenol and ethylene glycol act as hydrogen bond donors and can efficiently absorb ammonia; further indicating that the synergistic effect between the added choline chloride, phenol and ethylene glycol effectively improves the removal effect of the cement deamination agent.

[0127] Combined with the test results of Example 1, Example 2, Example 5, Comparative Example 3 and Comparative Example 4, it can be seen that the amount of phenol added has an impact on the removal effect of the prepared cement deamination agent. When the molar ratio of choline chloride, phenol and ethylene glycol is 1: (2-15): 4, the prepared cement deamination agents all meet the standards.

[0128] Combined with the test results of Example 1, Example 6, Example 9 and Comparative Example 5, it can be seen that the amount of ethylene glycol added has an impact on the removal effect of the prepared cement deamination agent. When the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:(1-8), the prepared cement deamination agents all meet the standards.

[0129] Combined with the test results of Example 1, Example 10, Example 11, Comparative Example 6 and Comparative Example 7, it can be seen that the temperature at which choline chloride, phenol and ethylene glycol are mixed has an influence on the removal effect of the cement deamination agent, and when the temperature at which choline chloride, phenol and ethylene glycol are mixed is 40-80°C, the removal effect of the cement deamination agent is best.

[0130] Combining the test results of Example 1 and Examples 12-14, it can be seen that the removal effect of cement deammoniation agent is effectively improved by modifying chitosan.

[0131] Performance test 2:

[0132] The cement deamination agent prepared above was used in a cement production plant (cement kiln adopts SCR denitrification) to remove ammonia generated in the cement production process. Without treatment, the flue gas volume during the flue gas emission process was 200000m 3 / h, flue gas composition (volume percentage): hydrogen 51.8%, nitrogen 19.3%, ammonia 6.5%, argon 3.6%, methane 18.8%; exhaust temperature 110℃, ammonia escape concentration 60mg / Nm 3 The products prepared in the above embodiments and comparative examples are used to remove ammonia from flue gas, and the ammonia removal capacity is tested. The specific steps are as follows: the cement deamination agent is directly sprayed into the flue after the high-temperature fan outlet to remove ammonia from the flue gas. The injection rate is 300 kg / h. The ammonia escape concentration of the treated flue gas is tested. The test results are as follows: the ammonia escape standard is 5 mg / m 3 .

[0133] Table 2 Ammonia removal results

[0134]

[0135]

[0136] It can be seen from Table 2 that the cement deammoniation agent prepared by the method of the present application can remove ammonia in the flue gas, and the ammonia escape concentration in the flue gas is less than 5 mg / Nm 3 .

[0137] Combined with the test results of Example 1 to Example 5, it can be seen that the amount of phenol added has an impact on the removal effect of the prepared cement deamination agent. When the molar ratio of choline chloride, phenol and ethylene glycol is 1: (2-15): 4, the prepared cement deamination agents all meet the standards; and when the molar ratio of choline chloride, phenol and ethylene glycol is 1: (5-9): 4, the removal effect of the prepared cement deamination agent is the best; It indicates that the synergistic effect between the added choline chloride, phenol and ethylene glycol effectively improves the removal effect of the cement deamination agent.

[0138] Combined with the test results of Example 1 and Examples 6-9, it can be seen that the amount of ethylene glycol added has an impact on the removal effect of the prepared cement deamination agent. When the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:(1-8), the prepared cement deamination agents all meet the standards; when the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:(2-6), the removal effect of the cement deamination agent is best; it shows that the synergistic effect between the added choline chloride, phenol and ethylene glycol effectively improves the removal effect of the cement deamination agent.

[0139] Combined with the test results of Example 1, Example 10 and Example 11, it can be seen that when the mixing temperature of choline chloride, phenol and ethylene glycol is 40-80°C, the prepared cement deamination agents all meet the standards, and when the mixing temperature is 60°C, the removal effect of the cement deamination agent is the best.

[0140] Combining the test results of Example 1 and Comparative Example 1, it can be seen that the removal effect of Example 1 is better than that of Comparative Example 1, indicating that the added choline chloride, as a hydrogen bond acceptor, helps to form a stable low eutectic solvent and reduce the volatilization of ethylene glycol, further indicating that the synergistic effect between the added choline chloride, phenol and ethylene glycol effectively improves the removal effect of the cement deamination agent.

[0141] Combining the test results of Example 1 and Comparative Example 2, it can be seen that the removal effect of Example 1 is better than that of Comparative Example 2, indicating that the added phenol is weakly acidic, so that its binding ability with ammonia is stronger than ordinary hydrogen bonding, thereby achieving efficient and reversible ammonia absorption; the added phenol and ethylene glycol act as hydrogen bond donors and can efficiently absorb ammonia; further indicating that the synergistic effect between the added choline chloride, phenol and ethylene glycol effectively improves the removal effect of the cement deamination agent.

[0142] Combined with the test results of Example 1, Example 2, Example 5, Comparative Example 3 and Comparative Example 4, it can be seen that the amount of phenol added has an impact on the removal effect of the prepared cement deamination agent. When the molar ratio of choline chloride, phenol and ethylene glycol is 1: (2-15): 4, the prepared cement deamination agents all meet the standards.

[0143] Combined with the test results of Example 1, Example 6, Example 9 and Comparative Example 5, it can be seen that the amount of ethylene glycol added has an impact on the removal effect of the prepared cement deamination agent. When the molar ratio of choline chloride, phenol and ethylene glycol is 1:7:(1-8), the prepared cement deamination agents all meet the standards.

[0144] Combined with the test results of Example 1, Example 10, Example 11, Comparative Example 6 and Comparative Example 7, it can be seen that the temperature at which choline chloride, phenol and ethylene glycol are mixed has an influence on the removal effect of the cement deamination agent, and when the temperature at which choline chloride, phenol and ethylene glycol are mixed is 40-80°C, the removal effect of the cement deamination agent is best.

[0145] Combining the test results of Example 1 and Examples 12-14, it can be seen that the removal effect of cement deammoniation agent is effectively improved by modifying chitosan.

Claims

1. A cement deamination agent, characterized in that: The method comprises the following raw material components in parts by weight: 20-30 parts of a low eutectic solvent, 10-20 parts of chitosan and 5-10 parts of a regenerated fiber hydrogel; Wherein, the low eutectic solvent comprises choline chloride, phenol and ethylene glycol; the molar ratio of choline chloride, phenol and ethylene glycol is 1:(2-15):(1-8); The preparation method of the cement deamination agent comprises the following steps: Weigh each raw material according to the formula; The chitosan powder was dissolved in acetic acid solution, stirred thoroughly at 25°C, the regenerated fiber hydrogel was added, and stirred for 30 minutes with a high-speed mechanical shearing machine at 15000r / min. After stirring evenly, vacuum degassing was performed; the mixed solution was then frozen in a refrigerator for 12 hours, and freeze-dried at a vacuum environment of -55°C for 48 hours to obtain a regenerated cellulose / chitosan aerogel material; a low eutectic solvent was then added and mixed and stirred for 30 minutes to obtain a cement deamination agent.

2. A cement deamination agent according to claim 1, characterized in that: The molar ratio of choline chloride, phenol and ethylene glycol is 1:(5-9):(2-6).

3. A cement deamination agent according to claim 1, characterized in that: The chitosan is modified in the following steps: chitosan and acetic acid are mixed, and then glutaraldehyde is added to react to obtain cross-linked modified chitosan.

4. A cement deammoniation agent according to claim 3, characterized in that: The mass ratio of chitosan to acetic acid is (1-4):(5-10), and the mass volume ratio of chitosan to glutaraldehyde is 1g:(1-2)ml.

5. A cement deammoniation agent according to claim 1, characterized in that: When preparing the deep eutectic solvent, the mixing temperature is 40-80°C.

6. Use of the cement deamination agent according to any one of claims 1 to 5 in removing ammonia.

7. The use according to claim 6, characterized in that: The steps of removing ammonia by cement deamination agent are as follows: the ammonia in the flue gas is removed by spraying cement deamination agent into the flue gas containing ammonia escape.

8. The use according to claim 7, characterized in that: The amount of flue gas containing ammonia escape is 150,000-250,000m³ / h.

9. The use according to claim 7, characterized in that: The injection amount of the cement deammoniation agent is 200-400kg / h.

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