A method for preparing and using an iron-based dehydrating conditioning agent

Abstract

The present application relates to the technical field of sludge treatment, and particularly relates to a preparation method and application of an iron-based dewatering conditioning agent, comprising: mixing inorganic sludge after drying with steel slag, adding ferrous salt and acid solution for stirring reaction, then performing solid-liquid separation to obtain precipitate A and acid leaching solution B; performing washing, drying, grinding and calcination on the precipitate A to obtain carbonized carrier C; mixing the acid leaching solution B with the carbonized carrier C for reaction, and performing solid-liquid separation, washing and drying to obtain the iron-based dewatering conditioning agent. The present application utilizes municipal multi-source solid waste to prepare porous medium carrier, and performs multi-phase nano-scale metal oxide particle modification on the surface, simultaneously utilizes the high specific surface area of the material and the multi-reaction active sites provided by the surface metal oxide particles, can effectively strengthen the advanced oxidation reaction efficiency, realizes efficient decomposition of organic matter in high-organic-matter sludge, and realizes the improvement of the dewatering performance of the high-organic-matter sludge.

Description

Technical Field

[0001] This invention relates to the field of sludge treatment technology, specifically to a method for preparing and applying an iron-based dehydration conditioning agent. Background Technology

[0002] The flocculent structure of sludge and the organic pollutants within it are the core factors limiting its dewatering performance. Compared to low-organic-matter sludge, high-organic-matter sludge has poorer dewatering performance and is difficult to dewater using traditional mechanical dewatering methods. It requires the use of various methods to condition and improve the dewatering performance of the sludge.

[0003] However, commonly used dewatering conditioners at present include quicklime, PAM, iron and aluminum salts, etc. Their main function is to promote sludge flocculation to form large flocs. They cannot effectively decompose organic pollutants in high organic matter sludge, making it difficult to enhance its dewatering performance and achieve deep dewatering of sludge. Summary of the Invention

[0004] This invention provides a method for preparing and applying an iron-based dewatering conditioning agent to solve the problem of difficult dewatering of sludge with high organic matter content.

[0005] In a first aspect, the present invention provides a method for preparing an iron-based dehydration conditioning agent, comprising:

[0006] The dried inorganic sludge was mixed with steel slag, and ferrous salt and acid solution were added and stirred to react. Then solid-liquid separation was carried out to obtain precipitate A and acid leaching solution B.

[0007] After washing, drying, grinding and calcining the precipitate A, carbonization carrier C is obtained;

[0008] The acid leaching solution B is mixed and reacted with the carbonized carrier C. After solid-liquid separation, washing, and drying, an iron-based dehydration conditioning agent is obtained.

[0009] In some embodiments of the present invention, the inorganic sludge, by dry weight, contains 30-70% SiO2, 15-35% Fe2O3, and 15-35% Al2O3.

[0010] The steel slag accounts for 5-15% of the mass of the inorganic sludge;

[0011] The ferrous salt accounts for 10-20% of the total mass of steel slag and inorganic sludge;

[0012] The acid solution is added at a solid-liquid ratio of 1g:5-15ml;

[0013] The acid solution is hydrochloric acid with a concentration of 1-5 mol / L.

[0014] In some embodiments of the present invention, the particle size of the precipitate A after grinding is 150-212 μm.

[0015] In some embodiments of the present invention, the calcination temperature of precipitate A is 300-450°C, the calcination time is 40-70 min, and the calcination atmosphere is an inert gas.

[0016] In some embodiments of the present invention, the acid leaching solution B includes at least Fe. 3+ Fe 2+ Al 3+ Ca 2+ Fe 3 + Fe 2+ The ratio is 2:1.2~1.7.

[0017] In some embodiments of the present invention, the mixing reaction of the acid leaching solution B and the carbonization carrier C includes: mixing the acid leaching solution B and the carbonization carrier C at a ratio of 1g:10-30ml and placing them in a reaction vessel, and reacting for 12-20 h at 200-250℃ and 200-350 r / min.

[0018] Secondly, the present invention also provides an iron-based dehydration conditioning agent, which is prepared by the preparation method described above.

[0019] Thirdly, the present invention also provides an application of an iron-based dewatering conditioning agent in the deep dewatering of high organic matter sludge.

[0020] In some experimental examples of the present invention, the deep dewatering process includes: adding an iron-based dewatering conditioning agent to high organic matter sludge, stirring evenly, and then performing ozone oxidation conditioning and concentration in an ozone atmosphere, followed by mechanical dewatering of the conditioned sludge.

[0021] In some experimental examples of the present invention, the iron-based dehydration conditioning agent accounts for 0.5-2.5% of the dry weight of the high organic matter sludge;

[0022] The high-organic-matter sludge contains more than 55% organic matter.

[0023] The reaction time for ozone oxidation is 15-30 minutes.

[0024] The ozone concentration in the ozone atmosphere is 100-200 mg / L.

[0025] The technical solution of this invention has the following advantages:

[0026] 1. The present invention provides a method for preparing an iron-based dehydration conditioning agent, comprising: mixing dried inorganic sludge (referring to sludge with an organic matter content of <30% on a dry basis, such as water supply sludge, pipe sludge, river and lake bottom sediment, etc.) with steel slag, adding ferrous salt and acid solution and stirring to react, and then performing solid-liquid separation to obtain precipitate A and acid leaching solution B; washing, drying, grinding and calcining precipitate A to obtain carbonized carrier C; mixing acid leaching solution B and carbonized carrier C to react, and after solid-liquid separation, washing and drying, obtaining the iron-based dehydration conditioning agent.

[0027] This invention utilizes urban multi-source solid waste to prepare a porous media carrier, and modifies the surface with multiphase nanoscale metal oxide particles. At the same time, by utilizing the high specific surface area of ​​the material and the multiple reactive sites provided by the surface metal oxide particles, the efficiency of advanced oxidation reactions can be effectively enhanced, achieving efficient decomposition of organic matter in high organic matter sludge and improving the dewatering performance of high organic matter sludge.

[0028] 2. In the preparation of the iron-based dehydration conditioning agent, the addition of ferrous salt in this invention can ensure the presence of Fe in the acid leaching solution B. 2+ Excessive amounts of precipitate A, mainly composed of steel slag, inorganic components from inorganic sludge including SiO2 and undissolved CaO, and undegraded organic matter from water supply sludge, lead to the carbonization and decomposition of organic matter after grinding and calcination. This process generates gas that creates pores, increasing the porosity and specific surface area of ​​the final carrier C. The carbonized carrier C then serves as a support for the Fe in the mixed solution. 3+ Fe 2+ Al 3+ When metal ions undergo phase transition on its surface, various metal nano-oxide particles, mainly Fe3O4, are generated.

[0029] 3. The iron-based dewatering conditioner prepared in this invention has a high specific surface area, which can simultaneously enhance the dewatering performance of sludge with high organic matter content through chemical catalysis and physical flocculation. Firstly, in terms of chemical catalysis, it provides more reaction points for the oxidation and cell disruption of sludge flocs: taking ozone advanced oxidation as an example, the Fe3O4 and other nano-metal oxides on the surface of the agent can effectively promote the decomposition of ozone into hydroxyl radicals (·OH), greatly enhancing its oxidation capacity and achieving efficient cell disruption of sludge with high organic matter content, releasing and decomposing the proteins and other organic pollutants encapsulated within, thus strengthening the dewatering performance of the sludge; Fe3O4 can provide a micro-magnetic field environment, promoting water molecule polarization, further enhancing the reaction efficiency of ozone catalytic oxidation. Secondly, in terms of physical flocculation, the Fe / Al elements on the surface of the agent and its own high specific surface area can also play a flocculation role, causing inorganic particles to agglomerate and enhancing the sludge dewatering performance. Attached Figure Description

[0030] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0031] Figure 1 This is a simplified diagram of the ozone flotation concentration reactor used in this invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1. Ozone aeration port. Detailed Implementation

[0034] The following embodiments are provided to better understand the present invention, but the following embodiments do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the scope of protection of the present invention.

[0035] Unless otherwise specified, the experimental steps or conditions in the examples were performed in accordance with conventional experimental procedures and conditions in the art. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0036] Example 1

[0037] This embodiment provides a method for preparing an iron-based dehydration conditioning agent, including:

[0038] The water supply sludge (with an organic matter content of 15%, and inorganic components containing 60%, 25%, and 10% SiO2, Fe2O3, and Al2O3, respectively, and a moisture content of 95%) was dried to constant weight in an oven at 105℃.

[0039] The water supply sludge and steel slag were mixed evenly, with the steel slag accounting for 5% of the inorganic sludge mass. Hydrochloric acid with a concentration of 3mol / L was added at a ratio of 1g:10ml, and ferrous chloride accounting for 15% of the total mass of the water supply sludge and steel slag was added. The mixture was ultrasonically stirred at room temperature for 30 minutes, and then solid-liquid separation was performed to obtain precipitate A and acid leaching solution B.

[0040] Precipitate A was washed and dried with deionized water, ground and passed through a 70-mesh sieve, and then calcined at 400℃ for 60 min in N2 environment to obtain carbonized support C.

[0041] Mix acid leaching solution B (which mainly consists of hydrochloric acid leaching solution containing metal elements from steel slag and sewage sludge) and ferrous chloride dissolved in ferrous chloride at a ratio of 1g:20ml, mainly including Fe2+. 3+ Fe 2+ Al 3+ Ca 2+ Metal ions, including Fe 3+ Fe 2+ The mixture of Fe3O4 and Fe3O4 (in a ratio of 2:1.5) with carbonization carrier C was added to a polytetrafluoroethylene high-pressure reactor and reacted at 230℃ and 300 r / min for 15 h. After cooling to room temperature, solid-liquid separation was performed. The precipitate was washed with deionized water and dried to obtain an iron-based dehydration conditioning agent D1 with a surface loaded with various metal nano-oxide particles, mainly Fe3O4.

[0042] Example 2

[0043] This embodiment provides a method for preparing an iron-based dehydration conditioning agent, including:

[0044] The sludge from the pipes and channels (the sludge has an organic matter content of 25%, and the contents of SiO2, Fe2O3 and Al2O3 in the inorganic components are 50%, 10% and 20% respectively, and the moisture content is 95%) was dried to constant weight in an oven at 80℃.

[0045] The water supply sludge and steel slag were mixed evenly, with the steel slag accounting for 15% of the mass of the water supply sludge. Hydrochloric acid with a concentration of 5mol / L was added at a ratio of 1g:10ml, and ferrous chloride accounting for 10% of the total mass of the water supply sludge and steel slag was added. The mixture was ultrasonically stirred at room temperature for 30 minutes, and then solid-liquid separation was performed to obtain precipitate A and acid leaching solution B.

[0046] Precipitate A was washed and dried with deionized water, ground and passed through a 70-mesh sieve, and then calcined at 450°C for 40 min in a N2 environment to obtain carbonized support C.

[0047] Mix acid leaching solution B (which mainly consists of hydrochloric acid leaching solution containing metal elements from steel slag and sewage sludge) and ferrous chloride dissolved in the solution at a ratio of 1g:10ml, mainly including Fe2+. 3+ Fe 2+ Al 3+ Ca 2+ Metal ions, including Fe 3+ Fe 2+The mixture of Fe3O4 and Fe3O4 in a ratio of 2:1.2 was added to a polytetrafluoroethylene high-pressure reactor and reacted at 200℃ and 350 r / min for 20 h. After cooling to room temperature, solid-liquid separation was performed. The precipitate was washed with deionized water and dried to obtain an iron-based dehydration conditioning agent D2 with Fe3O4 as the main metal nano-oxide particles on its surface.

[0048] Example 3

[0049] This embodiment provides a method for preparing an iron-based dehydration conditioning agent, including:

[0050] The water supply sludge (with an organic matter content of 20%, and inorganic components containing 70% SiO2, 10% Fe2O3, and 15% Al2O3, and a moisture content of 99%) was dried to constant weight in an oven at 120℃.

[0051] The water supply sludge and steel slag were mixed evenly, with the steel slag accounting for 15% of the mass of the water supply sludge. Hydrochloric acid with a concentration of 1 mol / L was added at a ratio of 1 g: 15 ml, and ferrous chloride accounting for 20% of the total mass of the water supply sludge and steel slag was added. The mixture was ultrasonically stirred at room temperature for 30 min, and then solid-liquid separation was performed to obtain precipitate A and acid leaching solution B.

[0052] Precipitate A was washed and dried with deionized water, ground and passed through a 100-mesh sieve, and calcined at 300°C for 70 min under an inert atmosphere to obtain carbonized support C.

[0053] Mix acid leaching solution B (which mainly consists of hydrochloric acid leaching solution containing metal elements from steel slag and sewage sludge) and ferrous chloride dissolved in ferrous chloride at a ratio of 1g:30ml, mainly including Fe2+. 3+ Fe 2+ Al 3+ Ca 2+ Metal ions, including Fe 3+ Fe 2+ The mixture of Fe3O4 and Fe3O4 (in a ratio of 2:1.7) with carbonization carrier C was added to a polytetrafluoroethylene high-pressure reactor and reacted at 250℃ and 200 r / min for 12 h. After cooling to room temperature, solid-liquid separation was performed. The precipitate was washed with deionized water and dried to obtain an iron-based dehydration conditioning agent D3 with a surface loaded with various metal nano-oxide particles, mainly Fe3O4.

[0054] Comparative Example 1

[0055] This comparative example provides a method for preparing an iron-based dehydration conditioning agent, including:

[0056] The water supply sludge (with an organic matter content of 15%, and inorganic components containing 60%, 25%, and 10% SiO2, Fe2O3, and Al2O3, respectively, and a moisture content of 95%) was dried to constant weight in an oven at 105℃.

[0057] The water supply sludge and steel slag were mixed evenly, with the steel slag accounting for 5% of the mass of the water supply sludge. Hydrochloric acid with a concentration of 3mol / L was added at a ratio of 1g:10ml. The mixture was ultrasonically stirred for 30min at room temperature, and then solid-liquid separation was performed to obtain precipitate A and acid leaching solution B.

[0058] Precipitate A was washed and dried with deionized water, ground and passed through a 70-mesh sieve, and calcined at 400℃ for 60 min under an inert atmosphere to obtain carbonized support C.

[0059] Mix acid leaching solution B (which is mainly a hydrochloric acid leaching solution containing metal elements from steel slag and sewage sludge, primarily including Fe) at a ratio of 1g:20ml. 3+ Al 3+ Ca 2+ The mixture of metal ions and carbonized carrier C was added to a polytetrafluoroethylene high-pressure reactor and reacted at 230℃ and 300 r / min for 15 h. After cooling to room temperature, solid-liquid separation was performed. The precipitate was washed with deionized water and dried to obtain iron-based dehydration conditioning agent E1.

[0060] Comparative Example 2

[0061] This comparative example provides a method for preparing an iron-based dehydration conditioning agent, including:

[0062] The water supply sludge (with an organic matter content of 15%, and inorganic components containing 60%, 25%, and 10% SiO2, Fe2O3, and Al2O3, respectively, and a moisture content of 95%) was dried to constant weight in an oven at 105℃.

[0063] The water supply sludge and steel slag were mixed evenly, with the steel slag accounting for 5% of the mass of the water supply sludge. Hydrochloric acid with a concentration of 0.1mol / L was added at a ratio of 1g:10ml, and ferrous chloride accounting for 15% of the total mass of the water supply sludge and steel slag was added. The mixture was ultrasonically stirred at room temperature for 30 minutes, and then solid-liquid separation was performed to obtain precipitate A and acid leaching solution B.

[0064] Precipitate A was washed and dried with deionized water, ground and passed through a 70-mesh sieve, and calcined at 400℃ for 60 min under an inert atmosphere to obtain carbonized support C.

[0065] Mix acid leaching solution B (which mainly consists of hydrochloric acid leaching solution containing metal elements from steel slag and sewage sludge) and ferrous chloride dissolved in ferrous chloride at a ratio of 1g:20ml, mainly including Fe2+.3+ Fe 2+ Al 3+ Ca 2+ Metal ions, including Fe 3+ Fe 2+ The mixture of Fe3O4 and Fe2O3 (in a ratio of 2:1.5) with carbonization carrier C was added to a polytetrafluoroethylene high-pressure reactor and reacted at 230℃ and 300 r / min for 15 h. After cooling to room temperature, solid-liquid separation was performed. The precipitate was washed with deionized water and dried to obtain an iron-based dehydration conditioning agent E2 with Fe3O4 as the main metal nano-oxide particles on its surface.

[0066] Experimental Example 1

[0067] This experimental example provides a method for using an iron-based dehydration conditioning agent, including:

[0068] The iron-based dewatering conditioner D1 prepared in Example 1 was added to concentrated high-organic-matter sludge (referring to sludge from a wastewater treatment plant after gravity thickening and sedimentation, with a water content of 98.5% and an organic matter content of 57%) and stirred evenly. The iron-based conditioner accounted for 0.5% of the dry weight of the high-organic-matter sludge. The mixture was then processed using... Figure 1 The ozone flotation thickening reactor shown is used to condition and thicken sludge after the addition of iron-based conditioning agents.

[0069] The reactor is a cylindrical tank with an internal spiral baffle structure. The baffle is used to assist the sludge to rise in a spiral flow to the discharge port after it is fed from the bottom. Ozone aeration ports 1 are provided above and below the baffle to facilitate efficient reaction with the sludge inside the tube.

[0070] The reaction time of the sludge in the ozone flotation thickening reactor is 30 minutes, and ozone is aerated until the ozone concentration is 100 mg / L.

[0071] After ozone oxidation conditioning, the sludge was dewatered using mechanical dewatering equipment. The moisture content of the dewatered sludge cake was tested by gravimetric method according to the "Standard Test Method for Urban Sludge" (CJ / T 221-2023). The test results showed that the moisture content of the dewatered sludge was 55% and the organic matter content was 44%.

[0072] Experiment Example 2

[0073] This experimental example provides a method for using an iron-based dehydration conditioning agent, including:

[0074] The iron-based dewatering conditioner D1 prepared in Example 1 was added to concentrated high-organic-matter sludge (referring to sludge from a wastewater treatment plant after gravity thickening and sedimentation, with a water content of 98.5% and an organic matter content of 57%) and stirred evenly. The iron-based conditioner accounted for 2.5% of the dry weight of the high-organic-matter sludge. The mixture was then processed using... Figure 1The ozone flotation thickening reactor shown is used to condition and thicken sludge after the addition of iron-based conditioning agents.

[0075] The reactor is a cylindrical tank with an internal spiral baffle structure. The baffle is used to assist the sludge to rise in a spiral flow to the discharge port after it is fed from the bottom. Ozone aeration ports 1 are provided above and below the baffle to facilitate efficient reaction with the sludge inside the tube.

[0076] The reaction time of the sludge in the ozone flotation thickening reactor is 15 minutes, and ozone is aerated until the ozone concentration is 200 mg / L.

[0077] After ozone oxidation conditioning, the sludge was dewatered using mechanical dewatering equipment. The dewatered sludge cake was tested for moisture content and organic matter content according to the "Standard Test Method for Urban Sludge" (CJ / T 221-2023). The test results showed that the moisture content of the dewatered sludge was 47% and the organic matter content was 32%.

[0078] Experimental Example 3

[0079] This experimental example provides a method for using an iron-based dehydration conditioning agent, including:

[0080] The iron-based dewatering conditioner D2 prepared in Example 2 was added to concentrated high-organic-matter sludge (referring to sludge from a wastewater treatment plant after gravity thickening and sedimentation, with a water content of 98.5% and an organic matter content of 57%) and stirred evenly. The iron-based conditioner accounted for 0.5% of the dry weight of the high-organic-matter sludge. The mixture was then processed using... Figure 1 The ozone flotation thickening reactor shown is used to condition and thicken sludge after the addition of iron-based conditioning agents.

[0081] The reactor is a cylindrical tank with an internal spiral baffle structure. The baffle is used to assist the sludge to rise in a spiral flow to the discharge port after it is fed from the bottom. Ozone aeration ports 1 are provided above and below the baffle to facilitate efficient reaction with the sludge inside the tube.

[0082] The reaction time of the sludge in the ozone flotation thickening reactor is 15 minutes, and ozone is aerated until the ozone concentration is 200 mg / L.

[0083] After ozone oxidation conditioning, the sludge was dewatered using mechanical dewatering equipment. The moisture content of the dewatered sludge cake was tested by gravimetric method according to the "Standard Test Method for Urban Sludge" (CJ / T 221-2023). The test results showed that the moisture content of the dewatered sludge was 52% and the organic matter content was 37%.

[0084] Comparative Experiment Example 1

[0085] This comparative experiment provides a method for using an iron-based dehydration conditioning agent, including:

[0086] The iron-based dewatering conditioner E1 prepared in Comparative Example 1 was added to concentrated high-organic-matter sludge (referring to sludge from a wastewater treatment plant after gravity thickening and sedimentation, with a water content of 98.5% and an organic matter content of 57%) and stirred evenly. The iron-based conditioner accounted for 0.5% of the dry weight of the high-organic-matter sludge. [The text then abruptly shifts to a different topic:] ...using... Figure 1 The ozone flotation thickening reactor shown is used to condition and thicken sludge after the addition of iron-based conditioning agents.

[0087] The reactor is a cylindrical tank with an internal spiral baffle structure. The baffle is used to assist the sludge to rise in a spiral flow to the discharge port after it is fed from the bottom. Ozone aeration ports 1 are provided above and below the baffle to facilitate efficient reaction with the sludge inside the tube.

[0088] The reaction time of the sludge in the ozone flotation thickening reactor is 30 minutes, and ozone is aerated until the ozone concentration is 100 mg / L.

[0089] After ozone oxidation conditioning, the sludge was dewatered using mechanical dewatering equipment. The moisture content of the dewatered sludge cake was tested by gravimetric method according to the "Standard Test Method for Urban Sludge" (CJ / T 221-2023). The test results showed that the moisture content of the dewatered sludge was 68% and the organic matter content was 49%.

[0090] In the preparation of the iron-based dehydration conditioning agent E1, the absence of ferrous chloride resulted in the inability to form Fe3O4 metal nano-oxide particles, leading to a reduction in catalytic performance.

[0091] Comparative Experiment Example 2

[0092] This comparative experiment provides a method for using an iron-based dehydration conditioning agent, including:

[0093] The iron-based dewatering conditioner E2 prepared in Comparative Example 2 was added to concentrated high-organic-matter sludge (referring to sludge from a wastewater treatment plant after gravity thickening and sedimentation, with a water content of 98.5% and an organic matter content of 57%) and stirred evenly. The iron-based conditioner accounted for 0.5% of the dry weight of the high-organic-matter sludge. [The text then abruptly shifts to a different topic:] ...using... Figure 1 The ozone flotation thickening reactor shown is used to condition and thicken sludge after the addition of iron-based conditioning agents.

[0094] The reactor is a cylindrical tank with an internal spiral baffle structure. The baffle is used to assist the sludge to rise in a spiral flow to the discharge port after it is fed from the bottom. Ozone aeration ports 1 are provided above and below the baffle to facilitate efficient reaction with the sludge inside the tube.

[0095] The reaction time of the sludge in the ozone flotation thickening reactor is 30 minutes, and ozone is aerated until the ozone concentration is 100 mg / L.

[0096] After ozone oxidation conditioning, the sludge was dewatered using mechanical dewatering equipment. The moisture content of the dewatered sludge cake was tested by gravimetric method according to the "Standard Test Method for Urban Sludge" (CJ / T 221-2023). The test results showed that the moisture content of the dewatered sludge was 74% and the organic matter content was 51%.

[0097] In the preparation of iron-based dehydration conditioning agent E2, the insufficient concentration of hydrochloric acid resulted in insufficient acid leaching of the material, fewer metal nano-oxide particles loaded on the surface of the carbonization support, and reduced catalytic performance.

[0098] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method of making an iron-based dehydrating conditioning agent, characterized in that, include: The dried inorganic sludge was mixed with steel slag, and ferrous salt and acid solution were added and stirred to react. Then solid-liquid separation was carried out to obtain precipitate A and acid leaching solution B. After washing, drying, grinding and calcining the precipitate A, carbonization carrier C is obtained; The acid leaching solution B is mixed and reacted with the carbonized carrier C. After solid-liquid separation, washing, and drying, an iron-based dehydration conditioning agent is obtained. The inorganic sludge, based on dry weight, contains 30-70% SiO2, 15-35% Fe2O3, and 15-35% Al2O3. The acid solution is hydrochloric acid with a concentration of 1-5 mol / L; The acid leaching solution B contains at least Fe. 3+ Fe 2+ Al 3+ Ca 2+ Fe 3+ Fe 2+ The ratio is 2:1.2~1.

7.

2. The method of claim 1, wherein, The steel slag accounts for 5-15% of the mass of the inorganic sludge; And / or, the ferrous salt accounts for 10-20% of the total mass of steel slag and inorganic sludge; And / or, the acid solution is added at a solid-liquid ratio of 1g:5-15ml.

3. The preparation method according to claim 1, characterized in that, The particle size of the precipitate A after grinding is 150-212 μm.

4. The production method according to claim 1 or 3, characterized by, The calcination temperature of precipitate A is 300-450℃, the calcination time is 40-70 min, and the calcination atmosphere is an inert gas.

5. The preparation method according to claim 1, characterized in that, The reaction of the acid leaching solution B with the carbonization carrier C includes: mixing the acid leaching solution B and the carbonization carrier C at a ratio of 1g:10-30ml and placing them in a reaction vessel, and reacting for 12-20 h at 200-250℃ and 200-350 r / min.

6. An iron-based dehydrating conditioning agent characterized by, It is prepared by the preparation method according to any one of claims 1-5.

7. The application of the iron-based dewatering conditioner according to claim 6 in the deep dewatering of high organic matter sludge.

8. Use according to claim 7, characterized in that, The deep dewatering process includes: adding an iron-based dewatering conditioning agent to high organic matter sludge, stirring evenly, and then performing ozone oxidation conditioning and concentration in an ozone atmosphere; the conditioned sludge is then mechanically dewatered.

9. Use according to claim 8, characterized in that, The iron-based dehydration conditioning agent accounts for 0.5-2.5% of the dry weight of the high organic matter sludge; And / or, the organic matter content in the high-organic-matter sludge is greater than 55%; And / or, the reaction time for ozone oxidation is 15-30 min; And / or, the ozone concentration of the ozone atmosphere is 100-200 mg / L.

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