High-temperature-resistant flocculant, preparation method and application thereof

Abstract

The application discloses a high-temperature-resistant flocculant and a preparation method and application thereof, and the flocculant is prepared from coal gasification slag, so that the medicament cost of a coal gasification wastewater treatment stage is reduced; the intelligent polymer is introduced into the application, so that the flocculant can automatically adjust the structure and performance thereof according to the reaction temperature, the reaction pH and the ion concentration, so as to adapt to the complex and changeable wastewater treatment requirements, thereby reducing the dependence on the reaction conditions, and then reducing the complexity of the wastewater treatment process and the environmental condition control cost; the surface activity treatment is performed on the flocculant, so that the ability of the flocculant to capture heavy metal ions is improved, and thus the wastewater treatment effect is improved.

Description

Technical Field

[0001] This invention relates to the field of coal gasification technology, specifically to a high-temperature resistant flocculant and its preparation method, and its application in coal gasification processes. Background Technology

[0002] Coal gasification is a chemical technology that converts coal into combustible gas. The commonly used coal gasification technology is pressurized coal-water slurry gasification. Since this technology consumes a large amount of water, a wastewater recycling process is generally added to the coal gasification process to save water. That is, the dewatered filtrate after flash evaporation of the gasifier exhaust water and the scrubbing tower exhaust water is reused as makeup water for coal-water slurry preparation. The ash water is partially used as makeup circulating water for the scrubbing tower after heat exchange, and part of it is cooled and discharged as sewage to the biochemical sewage treatment system. After treatment to meet the standards, it is either discharged or reused.

[0003] Flocculants are required in the wastewater recovery process of coal gasification to coagulate and flocculate suspended solids and colloidal particles in the wastewater, forming larger particles that accelerate sedimentation and reduce suspended solids and turbidity. However, existing coal gasification wastewater treatment processes using flocculants have the following drawbacks: First, the wastewater treatment process consumes a large amount of flocculant, resulting in high costs. Second, to achieve optimal flocculant capture capacity, strict control of the reaction environment is necessary, increasing the complexity of the wastewater treatment process and further raising costs. Third, the flocculants used in existing wastewater treatment processes have poor capture capacity for heavy metal ions, leading to high concentrations of heavy metal ions in the treated wastewater, which affects subsequent wastewater treatment. Summary of the Invention

[0004] In view of the above-mentioned problems in the prior art, the purpose of this invention is to provide a high-temperature resistant flocculant and its preparation method.

[0005] The present invention also aims to provide the application of the high-temperature resistant flocculant in the treatment of wastewater from coal gasification processes, which has the advantages of low cost, strong adaptability, and high efficiency.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a method for preparing a high-temperature resistant flocculant, comprising the following steps:

[0008] 1) Mix the coal gasification slag with the acid solution, stir and react thoroughly, separate the liquid phase, and obtain the coal gasification slag acid leaching filtrate;

[0009] 2) Add calcium aluminate to the acid leaching filtrate of the coal gasification slag from step 1) and stir thoroughly to react;

[0010] 3) Add 3-mercaptopropyltrimethoxysilane to the reaction solution in step 2) and stir thoroughly to react;

[0011] 4) Add ethylenediamine to the reaction solution from step 3) and stir thoroughly to allow the reaction to proceed.

[0012] 5) Add the temperature-responsive polymer, pH-responsive polymer, and ion concentration-responsive polymer to the reaction solution in step 4), and stir the reaction thoroughly.

[0013] 6) The reaction solution from step 5) is filtered, dried, and ground to obtain the high-temperature resistant flocculant.

[0014] In one specific implementation, the coal gasification slag in step 1) needs to be crushed and screened, and the particle size after screening is 150-300μm.

[0015] The coal gasification slag refers to the solid waste produced after coal undergoes a chemical reaction with a gasifying agent (such as oxygen, water vapor, etc.) in a gasifier under high temperature and pressure. Its main components include ash (containing silicon oxide, aluminum oxide, iron oxide, etc.), unreacted carbon, metal compounds, sulfides or sulfates, and other trace components.

[0016] The source of the coal gasification slag is not particularly required in this invention. For example, it can be a solid waste generated after coal gasification, such as bituminous coal, anthracite, or lignite.

[0017] In one specific embodiment, the acid solution in step 1) is an aqueous acid solution with a concentration of 100-500 g / L; preferably, the acid is any one or more of hydrochloric acid, sulfuric acid, nitric acid, and hydrofluoric acid.

[0018] In one specific implementation, the mass ratio of the acid solution to the coal gasification slag in step 1) is 3-7:1.

[0019] In one specific implementation, the stirring reaction in step 1) is carried out at a temperature of 70-110℃, a stirring speed of 300-500 rpm, and a stirring reaction time of 60-300 min. In this step, an acid solution (such as hydrochloric acid, sulfuric acid, or nitric acid) is used to react chemically with the metal oxides and other components in the coal gasification slag to achieve the dissolution and extraction of valuable metals.

[0020] In practical applications, in order to fully extract the effective components from the coal gasification slag, the acid washing operation in step 1) can be repeated, for example, by repeating the stirring reaction 1-4 times; after the reaction is completed, conventional methods such as filtration can be used to separate the liquid phase.

[0021] In one specific implementation, the mass ratio of the acid leaching filtrate of the coal gasification slag in step 2) to calcium aluminate is 3-6:1.

[0022] In one specific implementation, the stirring reaction in step 2) is carried out at a temperature of 60-90°C, a stirring speed of 200-300 rpm, and a stirring reaction time of 60-180 min.

[0023] In one specific embodiment, the molar ratio of 3-mercaptopropyltrimethoxysilane in step 3) to aluminum ions in the reaction solution of step 2) is 0.5-3:1.

[0024] In one specific implementation, the stirring reaction in step 3) is carried out at a temperature of 30-60°C, a stirring speed of 150-200 rpm, and a stirring reaction time of 90-150 min.

[0025] In one specific implementation, the molar ratio of ethylenediamine in step 4) to aluminum ions in the reaction solution of step 3) is 0.4-1:1.

[0026] In one specific implementation, the stirring reaction in step 4) is carried out at a temperature of 30-60°C, a stirring speed of 150-200 rpm, and a stirring reaction time of 50-90 min.

[0027] In one specific embodiment, the temperature-responsive polymer in step 5) is selected from one or more of polyoxyethylene-polyoxypropylene copolymer, polyN-isopropylacrylamide, polyN,N-dimethylacrylamide, and polyethylene glycol, preferably polyN-isopropylacrylamide, with a degree of polymerization of 10,000-25,000; the temperature-responsive polymer can enhance the flocculation effect, provide intelligent regulation capability, improve dispersibility and stability, and can expand the application range of flocculants by controlling the release behavior;

[0028] Preferably, the mass ratio of the temperature-responsive polymer to the reaction solution in step 4) is 1-10%.

[0029] In one specific implementation, the pH-responsive polymer in step 5) is selected from one or more of polymethacrylic acid, poly(2-vinylpyridine), and poly(4-vinylphenol), preferably polyacrylic acid; the pH-responsive polymer can enhance flocculation effect, regulate solubility and dispersibility, improve floc characteristics and stability, and improve overall performance through synergistic effect;

[0030] Preferably, the mass ratio of the pH-responsive polymer to the reaction solution in step 4) is 1-10%.

[0031] In one specific implementation, the ion concentration-responsive polymer in step 5) is selected from one or more of sodium polyacrylate, sodium polystyrene sulfonate, and polyethyleneimine, preferably sodium polystyrene sulfonate; the ion concentration-responsive polymer utilizes the anionic charge it provides to enhance flocculation effect, improve floc characteristics and stability, and adjust solution properties.

[0032] Preferably, the mass ratio of the ion concentration-responsive polymer to the reaction solution in step 4) is 0.1-0.5%.

[0033] In one specific implementation, the stirring reaction in step 5) is carried out at a temperature of 20-60°C, a stirring speed of 100-200 rpm, and a stirring reaction time of 30-90 min.

[0034] In one specific implementation, the filtering, drying, and grinding in step 6) are all conventional operations in the field. Preferably, the drying process specifically involves drying in an oven at 80-100°C for 7-10 hours. Preferably, the particle size of the flocculant obtained by the grinding process is 70-100 μm.

[0035] Secondly, the present invention provides a high-temperature resistant flocculant prepared by the above method;

[0036] The flocculant has the advantages of low cost, strong adaptability, and high efficiency, and can withstand high temperatures above 150°C.

[0037] Thirdly, the present invention provides applications of the above-mentioned high-temperature resistant flocculant, which can be used in industrial wastewater treatment, oilfield and oil extraction operations, power industry and other fields, and is especially suitable for coal gasification wastewater treatment.

[0038] Specifically, one application is in the wastewater treatment stage of the coal gasification process, where the flocculant described in this invention is used to treat coal gasification wastewater.

[0039] The coal gasification wastewater treated by the flocculant described in this invention can achieve a turbidity removal rate of 93.36% and a heavy metal removal rate of 67%.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] This invention uses coal gasification slag to prepare flocculants, which reduces the reagent costs in the wastewater treatment stage of the coal gasification process.

[0042] This invention introduces a smart polymer composed of temperature-responsive polymers, pH-responsive polymers, and ion concentration-responsive polymers, enabling the flocculant to automatically adjust its structure and performance according to the reaction temperature, reaction pH, and ion concentration to adapt to complex and ever-changing wastewater treatment needs, thereby reducing dependence on reaction conditions and consequently reducing the complexity of wastewater treatment processes and environmental control costs.

[0043] This invention improves the ability of flocculants to capture heavy metal ions by surface-activating the flocculants, thereby enhancing the wastewater treatment effect. Detailed Implementation

[0044] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0045] The main raw materials used in the various embodiments and comparative examples of this invention are sourced as follows. Unless otherwise specified, other raw materials and reagents were obtained through commercially available channels:

[0046] hydrochloric acid Sinopharm Chemical Reagent Co., Ltd. sulfuric acid Sinopharm Chemical Reagent Co., Ltd. Nitric acid Sinopharm Chemical Reagent Co., Ltd. Calcium aluminate Sinopharm Chemical Reagent Co., Ltd. 3-Mercaptopropyltrimethoxysilane Sinopharm Chemical Reagent Co., Ltd. ethylenediamine Sinopharm Chemical Reagent Co., Ltd. Polyoxyethylene-polyoxypropylene copolymer Sinopharm Chemical Reagent Co., Ltd. Poly-N-isopropylacrylamide Sinopharm Chemical Reagent Co., Ltd. Poly N,N-dimethylacrylamide Polymer Source polyethylene glycol Sinopharm Chemical Reagent Co., Ltd. polymethacrylic acid Sinopharm Chemical Reagent Co., Ltd. Poly-2-vinylpyridine Sigma Poly(4-vinylphenol) Sigma Sodium polyacrylate Sigma Sodium polystyrene sulfonate Sinopharm Chemical Reagent Co., Ltd. Polyethyleneimine Sinopharm Chemical Reagent Co., Ltd.

[0047] Coal gasification slag: This is a solid waste product generated after coal gasification at Baling Petrochemical, and its specific composition is shown in Table 1.

[0048] Table 1 Composition of Coal Gasification Slag

[0049]

[0050] The main analytical methods used in the embodiments and comparative examples of this invention are as follows:

[0051] (1) The standard method for turbidity testing refers to GB 13200-1991;

[0052] (2) The method for detecting heavy metal content refers to GB / T 38596-2020.

[0053] Example 1

[0054] Preparation of high-temperature resistant flocculants:

[0055] 1) Mix coal gasification slag with a 100 g / L hydrochloric acid aqueous solution at a mass ratio of 1:3, stir thoroughly, and react at a temperature of 70℃, a stirring speed of 300 rpm, and a stirring time of 60 min. Separate the liquid phase and repeat the operation 4 times to obtain the acid leaching filtrate of coal gasification slag.

[0056] 2) Add calcium aluminate to the acid leaching filtrate of coal gasification slag in step 1), with a mass ratio of 3:1 between the acid leaching filtrate and calcium aluminate. Stir the mixture thoroughly at a temperature of 60°C, a stirring speed of 200 rpm, and a stirring time of 60 min.

[0057] 3) Add 3-mercaptopropyltrimethoxysilane to the reaction solution in step 2), the molar ratio of 3-mercaptopropyltrimethoxysilane to aluminum ions in the reaction solution in step 2) is 0.5:1, stir the reaction thoroughly, the temperature of the stirring reaction is 30℃, the stirring speed is 150n / min, and the stirring reaction time is 90min.

[0058] 4) Add ethylenediamine to the reaction solution in step 3), the molar ratio of ethylenediamine to aluminum ions in the reaction solution in step 3) is 0.4:1, stir the reaction thoroughly, the temperature of the stirring reaction is 30℃, the stirring speed is 150n / min, and the stirring reaction time is 50min;

[0059] 5) Add poly(N-isopropylacrylamide) (temperature-responsive polymer), polyacrylic acid (pH-responsive polymer), and sodium polystyrene sulfonate (ion concentration-responsive polymer) to the reaction solution in step 4), and stir thoroughly to react;

[0060] The mass ratios of poly(N-isopropylacrylamide), polyacrylic acid, and sodium polystyrene sulfonate to the reaction solution in step 4) are 1%, 1%, and 0.1%, respectively; the stirring temperature is 50°C, the stirring speed is 100 rpm, and the stirring time is 90 min.

[0061] 6) The reaction solution from step 5) is filtered, dried in an oven at 80-100℃ for 7 hours, and ground into particles with a particle size of 70-100μm to obtain a high-temperature resistant flocculant.

[0062] Example 2

[0063] Preparation of high-temperature resistant flocculants:

[0064] 1) Mix coal gasification slag with a 200 g / L hydrochloric acid aqueous solution at a mass ratio of 1:4, stir thoroughly, and react at a temperature of 80℃, a stirring speed of 350 n / min, and a stirring time of 120 min. Separate the liquid phase and repeat the operation 4 times to obtain the acid leaching filtrate of coal gasification slag.

[0065] 2) Add calcium aluminate to the acid leaching filtrate of coal gasification slag in step 1), with a mass ratio of 4:1 between the acid leaching filtrate and calcium aluminate. Stir the mixture thoroughly at a temperature of 70°C, a stirring speed of 200 rpm, and a stirring time of 90 min.

[0066] 3) Add 3-mercaptopropyltrimethoxysilane to the reaction solution in step 2), the molar ratio of 3-mercaptopropyltrimethoxysilane to aluminum ions in the reaction solution in step 2) is 1:1, stir the reaction thoroughly, the temperature of the stirring reaction is 40℃, the stirring speed is 180n / min, and the stirring reaction time is 120min.

[0067] 4) Add ethylenediamine to the reaction solution in step 3), the molar ratio of ethylenediamine to aluminum ions in the reaction solution in step 3) is 0.6:1, stir the reaction thoroughly, the stirring temperature is 40℃, the stirring speed is 180n / min, and the stirring time is 60min.

[0068] 5) Add polyethylene glycol, polymethacrylic acid, and polyethyleneimine to the reaction solution in step 4), and stir thoroughly to react;

[0069] The mass ratios of polyethylene glycol, polymethacrylic acid, and polyethyleneimine to the reaction solution in step 4) are 5%, 5%, and 0.2%, respectively; the stirring temperature is 60℃, the stirring speed is 100 rpm, and the stirring time is 60 min.

[0070] 6) The reaction solution from step 5) is filtered, dried in an oven at 80-100℃ for 8 hours, and ground into particles with a particle size of 70-100μm to obtain a high-temperature resistant flocculant.

[0071] Example 3

[0072] Preparation of high-temperature resistant flocculants:

[0073] 1) Mix coal gasification slag with a 500 g / L hydrochloric acid aqueous solution at a mass ratio of 1:5, stir thoroughly, and react at a temperature of 80℃, a stirring speed of 400 n / min, and a stirring time of 240 min. Separate the liquid phase and repeat the operation 4 times to obtain the acid leaching filtrate of coal gasification slag.

[0074] 2) Add calcium aluminate to the acid leaching filtrate of the coal gasification slag in step 1), with a mass ratio of 4:1 between the acid leaching filtrate and calcium aluminate. Stir the mixture thoroughly at a temperature of 80°C, a stirring speed of 250 N / min, and a stirring time of 180 min.

[0075] 3) Add 3-mercaptopropyltrimethoxysilane to the reaction solution in step 2), the molar ratio of 3-mercaptopropyltrimethoxysilane to aluminum ions in the reaction solution in step 2) is 2:1, stir the reaction thoroughly, the temperature of the stirring reaction is 40℃, the stirring speed is 200n / min, and the stirring reaction time is 120min.

[0076] 4) Add ethylenediamine to the reaction solution in step 3), the molar ratio of ethylenediamine to aluminum ions in the reaction solution in step 3) is 1:1, stir the reaction thoroughly, the stirring temperature is 40℃, the stirring speed is 180n / min, and the stirring time is 80min.

[0077] 5) Add polyethylene glycol, poly-2-vinylpyridine, and sodium polyacrylate to the reaction solution from step 4), and stir thoroughly to allow the reaction to proceed.

[0078] The mass ratios of polyethylene glycol, poly(2-vinylpyridine), and sodium polyacrylate to the reaction solution in step 4) were 6%, 8%, and 0.4%, respectively; the stirring temperature was 60°C, the stirring speed was 180 rpm, and the stirring time was 70 min.

[0079] 6) The reaction solution from step 5) is filtered, dried in an oven at 80-100℃ for 9 hours, and ground into particles with a particle size of 70-100μm to obtain a high-temperature resistant flocculant.

[0080] Comparative Example 1

[0081] The preparation method is the same as in Example 1, except that step 2) of adding calcium aluminate is omitted, and the acid leaching filtrate of coal gasification slag in step 1) is directly used in step 3). Other operations and raw materials remain unchanged to obtain flocculant.

[0082] Comparative Example 2

[0083] The preparation method is the same as in Example 1, except that step 3) of adding 3-mercaptopropyltrimethoxysilane is omitted, and the reaction solution in step 2) is directly used in step 4). Other operations and raw materials remain unchanged to obtain the flocculant.

[0084] Comparative Example 3

[0085] The preparation method is the same as in Example 1, except that step 4) of adding ethylenediamine is omitted, and the reaction solution in step 3) is directly used in step 5). Other operations and raw materials remain unchanged to obtain the flocculant.

[0086] Comparative Example 4

[0087] The preparation method is the same as in Example 1, except that in step 5), poly-N-isopropylacrylamide (temperature-responsive polymer) is not added, while other operations and raw materials remain unchanged, and flocculant is obtained.

[0088] Comparative Example 5

[0089] The preparation method is the same as in Example 1, except that polyacrylic acid (pH-responsive polymer) is not added in step 5), while other operations and raw materials remain unchanged, and flocculant is obtained.

[0090] Comparative Example 6

[0091] The preparation method is the same as in Example 1, except that sodium polystyrene sulfonate (an ion concentration-responsive polymer) is not added in step 5), while other operations and raw materials remain unchanged, and the flocculant is obtained.

[0092] The flocculants prepared in Examples 1-3 and Comparative Examples 1-6 were used to treat coal gasification wastewater. The treatment method and steps were as follows:

[0093] (1) Take 0.1g of flocculant, dilute it with water to 100g, and stir for 1 hour;

[0094] (2) Take 200 mL of coal gasification wastewater into a 300 mL hydrothermal reactor and add 10 mL of diluted flocculant;

[0095] (3) The above solution was hydrothermally treated at 180°C for 2 hours;

[0096] (4) After hydrothermal treatment, stir at 250 rpm for 2 min;

[0097] (5) Stir at 250 rpm for 30 seconds;

[0098] (6) Slowly reduce the speed to 100 rpm and stir for 20 minutes;

[0099] (7) After standing for 10 minutes, take the supernatant and measure the turbidity and heavy metal content.

[0100] The test results are shown in Table 2 below.

[0101] Table 2 compares the treatment effects of the flocculants prepared in the examples and comparative examples on coal gasification wastewater (180℃).

[0102]

[0103] Following the above treatment method, the flocculant prepared in Example 1 was used to test the effect of different addition amounts on the treatment effect of coal gasification wastewater. The results are shown in Table 3.

[0104] Table 3. Comparison of the treatment effects of flocculant solutions with different dosages on coal gasification wastewater.

[0105]

[0106] Based on the above, the advantages of this invention are as follows: When used, this invention employs coal gasification slag to prepare a low-cost aluminum-containing composite flocculant, thereby reducing the cost of flocculants in the wastewater treatment stage of the coal gasification process; by introducing intelligent polymers, this invention enables the flocculant to automatically adjust its structure and performance according to reaction temperature, reaction pH, and ion concentration to adapt to the complex and ever-changing needs of coal gasification wastewater treatment, thereby reducing the complexity of wastewater treatment processes and the increased costs due to controlling environmental conditions; by introducing thiol and amino groups, this invention allows thiol groups to form stable complexes with heavy metal ions, and amino groups to enhance the electrostatic attraction between the flocculant and negatively charged pollutant particles, improving the flocculation effect and also enhancing the solubility and dispersibility of the flocculant, thereby improving the wastewater treatment effect and reducing the amount of flocculant used.

[0107] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A method for preparing a high-temperature resistant flocculant, characterized in that, Includes the following steps: 1) Mix the coal gasification slag with the acid solution, stir and react thoroughly, separate the liquid phase, and obtain the coal gasification slag acid leaching filtrate; 2) Add calcium aluminate to the acid leaching filtrate of the coal gasification slag from step 1) and stir thoroughly to react; 3) Add 3-mercaptopropyltrimethoxysilane to the reaction solution in step 2) and stir thoroughly to react; 4) Add ethylenediamine to the reaction solution from step 3) and stir thoroughly to allow the reaction to proceed. 5) Add the temperature-responsive polymer, pH-responsive polymer, and ion concentration-responsive polymer to the reaction solution in step 4), and stir the reaction thoroughly; 6) The reaction solution from step 5) is filtered, dried, and ground to obtain the high-temperature resistant flocculant; In step 5), the temperature-responsive polymer is selected from one or more of polyoxyethylene-polyoxypropylene copolymer, poly-N-isopropylacrylamide, poly-N,N-dimethylacrylamide, and polyethylene glycol; the pH-responsive polymer is selected from one or more of polymethacrylic acid, poly(2-vinylpyridine), and poly(4-vinylphenol); and the ion concentration-responsive polymer is selected from one or more of sodium polyacrylate, sodium polystyrene sulfonate, and polyethyleneimine.

2. The preparation method according to claim 1, characterized in that, Step 1) The coal gasification slag needs to be crushed and screened, and the particle size after screening is 150-300μm; and / or Step 1) The acid solution is an aqueous acid solution with a concentration of 100-500 g / L; and / or Step 1) The mass ratio of the acid solution to the coal gasification slag is 3-7:1; and / or The stirring reaction in step 1) is carried out at a temperature of 70-110℃, a stirring speed of 300-500 rpm, and a stirring reaction time of 60-300 min.

3. The preparation method according to claim 1, characterized in that, Step 1) The acid is any one or more of hydrochloric acid, sulfuric acid, nitric acid, and hydrofluoric acid.

4. The preparation method according to claim 1, characterized in that, Step 2) The mass ratio of the acid leaching filtrate of the coal gasification slag to calcium aluminate is 3-6:1; and / or The stirring reaction in step 2) is carried out at a temperature of 60-90℃, a stirring speed of 200-300 rpm, and a stirring reaction time of 60-180 min.

5. The preparation method according to claim 1, characterized in that, In step 3), the molar ratio of 3-mercaptopropyltrimethoxysilane to aluminum ions in the reaction solution of step 2) is 0.5-3:1; and / or Step 3) The stirring reaction is carried out at a temperature of 30-60℃, a stirring speed of 150-200n / min, and a stirring reaction time of 90-150min.

6. The preparation method according to claim 1, characterized in that, In step 4), the molar ratio of ethylenediamine to aluminum ions in the reaction solution of step 3) is 0.4-1:1; and / or Step 4) The stirring reaction is carried out at a temperature of 30-60℃, a stirring speed of 150-200 rpm, and a stirring reaction time of 50-90 min.

7. The preparation method according to claim 1, characterized in that, Step 5) The degree of polymerization of the temperature-responsive polymer is 10000-25000; and / or Step 5) The mass ratio of the pH-responsive polymer to the reaction solution in step 4) is 1-10%; and / or Step 5) The mass ratio of the ion concentration-responsive polymer to the reaction solution in step 4) is 0.1-0.5%; and / or Step 5) describes a stirring reaction at a temperature of 20-60℃, a stirring speed of 100-200 rpm, and a stirring reaction time of 30-90 min.

8. The preparation method according to claim 1, characterized in that, The mass ratio of the temperature-responsive polymer in step 5) to the reaction solution in step 4) is 1-10%.

9. The preparation method according to claim 1, characterized in that, Step 6) involves drying at a temperature of 80-100℃ for 7-10 hours; and / or Step 6) The flocculant obtained by the grinding process has a particle size of 70-100 μm.

10. A high-temperature resistant flocculant prepared by the method according to any one of claims 1-9.

11. The application of the high-temperature resistant flocculant prepared by the method of any one of claims 1-9 or the high-temperature resistant flocculant of claim 10 in the fields of industrial wastewater treatment, oilfield and oil production operations, and power industry.

12. The application according to claim 11, characterized in that, Used for treating wastewater from coal gasification.

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