A method for preparing a sludge-derived biomass sorbent

Abstract

This invention provides a method for preparing a sludge-derived biomass adsorbent. The method includes: selecting municipal sludge, bentonite, and straw, and mixing them to obtain a mixed raw material; placing the mixed raw material in a pyrolysis furnace and performing low-temperature pyrolysis at 350℃~450℃ to obtain a primary carbonized product; placing the primary carbonized product in a microwave activation furnace and performing microwave activation at a microwave power of 300 W~500 W and an activation temperature of 500℃~550℃ to obtain an activated product; pulverizing the activated product, adding a starch binder and deionized water, and stirring to obtain a plastic material; and extruding and drying the plastic material to obtain the sludge-derived biomass adsorbent. This method is green and environmentally friendly, achieving co-resource utilization of solid waste; it has low energy consumption, simple steps, and high efficiency, solving the problem of uneven product performance; it achieves a synergistic effect of green, high performance, and low cost, breaking through existing technological bottlenecks.

Description

Technical Field

[0001] This invention belongs to the field of biomass adsorbent technology, specifically relating to a method for preparing a sludge-derived biomass adsorbent. Background Technology

[0002] Sludge is a major byproduct of wastewater treatment, characterized by its large quantity, high water content, easy putrefaction and odor, and complex composition. Its harmless treatment, reduction, and resource utilization have become important issues in environmental governance. Converting sludge into biomass adsorbents—treating waste with waste and maximizing resource value—is currently the mainstream technological direction in the intersection of sludge disposal and water pollution control.

[0003] Existing sludge-based adsorbents are mostly prepared using pyrolysis carbonization, hydrothermal carbonization, chemical activation, physical activation, and combinations thereof. Among these, direct pyrolysis is simple and widely applicable, but the product has a low specific surface area, underdeveloped pore structure, and limited adsorption capacity. Chemical activation often uses strong acids, strong bases, zinc salts, etc., as activators, which can significantly increase specific surface area and porosity, but suffers from problems such as strong corrosiveness of activators, high equipment requirements, complex post-treatment, easy generation of secondary pollution, and high cost. Hydrothermal carbonization can adapt to sludge with high water content, but suffers from defects such as incomplete carbonization, poor product stability, uneven distribution of functional groups, and insufficient regeneration performance. Improved processes such as microwave pyrolysis and catalytic activation have improved heating uniformity and reaction efficiency, but still face bottlenecks such as poor product performance consistency due to fluctuations in sludge composition, insufficient heavy metal fixation, and difficulty in industrial scale-up.

[0004] Meanwhile, traditional sludge adsorbents generally suffer from shortcomings such as simple pore structure, insufficient active sites, weak adsorption selectivity, low mechanical strength, and easy pulverization and loss after long-term use. They are difficult to meet the high-efficiency adsorption requirements for complex pollutants such as heavy metals, organic matter, nitrogen and phosphorus, which also limits their stable application in engineering water treatment.

[0005] Existing technologies for preparing sludge-derived adsorbents have not yet formed an integrated preparation scheme that is green and low-consumption, has controllable pore structure, rich functional groups, stable performance, and is environmentally friendly. It is difficult to balance resource utilization efficiency, adsorption performance, and environmental safety. There is an urgent need to develop new preparation methods to overcome the above-mentioned technical limitations.

[0006] To address the aforementioned issues, it is necessary to propose a reasonable and effective method for preparing sludge-derived biomass adsorbents. Summary of the Invention

[0007] The present invention aims to at least solve one of the technical problems existing in the prior art, and provides a method for preparing sludge-derived biomass adsorbent.

[0008] One aspect of the present invention provides a method for preparing a sludge-derived biomass adsorbent, the method comprising: Municipal sludge, bentonite, and straw were selected and mixed separately to obtain a mixed raw material; The mixed raw materials are placed in a pyrolysis furnace and subjected to low-temperature pyrolysis at 350℃~450℃ to obtain primary carbonized products. The primary carbonized product was placed in a microwave activation furnace and microwave activated at a microwave power of 300 W to 500 W and an activation temperature of 500°C to 550°C to obtain the activated product. The activated product was pulverized, starch binder was added, and deionized water was added and stirred to obtain a plastic material. The plastic material is extruded and dried to obtain a sludge-derived biomass adsorbent.

[0009] Optionally, after obtaining the activated product, the preparation method further includes: After cooling, the activated product is washed 3-4 times with deionized water, and then dried in a drying oven at 105℃-110℃ for 2-3 hours.

[0010] Optionally, the mixed raw materials are placed in a pyrolysis furnace and subjected to low-temperature pyrolysis at 350℃~450℃ to obtain primary carbonized products, including: The mixed raw materials are placed in a pyrolysis furnace, nitrogen gas is introduced, the pyrolysis temperature is controlled at 350℃~450℃, the pyrolysis time is 40 min~60 min, and the pyrolysis heating rate is 5℃ / min~8℃ / min, and low-temperature pyrolysis is carried out to obtain the primary carbonized product.

[0011] Optionally, the primary carbonization product is placed in a microwave activation furnace and microwave activated at a microwave power of 300 W to 500 W and an activation temperature of 500℃ to 550℃ to obtain an activated product, comprising: The primary carbonized product is fed into a microwave activation furnace, the microwave power is adjusted to 300 W ~ 500 W, the activation temperature is 500℃ ~ 550℃, the activation time is 30 min ~ 45 min, the microwave frequency is 2450 MHz ~ 2500 MHz, and nitrogen gas is continuously introduced during the activation process to obtain the activated product.

[0012] Optionally, the activated product is pulverized, a starch binder is added, and deionized water is added and stirred to obtain a plastic material, comprising: The activated product is pulverized and passed through an 80-100 mesh sieve; Add 5% to 8% (by weight of the activated product) of starch binder; Add deionized water and stir to obtain the plastic material.

[0013] Optionally, the plastic material is extruded, including: The plastic material is fed into an extrusion molding machine and extruded into columnar granules at a molding pressure of 0.3 MPa to 0.5 MPa.

[0014] Optionally, drying the plastic material includes: The formed columnar particles are placed in a drying oven and dried at 100℃~105℃ for 1.5h~2h. Transfer to a muffle furnace and bake at 200℃~250℃ for 30 min~40 min.

[0015] Optionally, municipal sludge, bentonite, and straw are selected and mixed separately to obtain a mixed raw material, including: The sludge, bentonite, and straw are mixed in a mass ratio of 100:(15-25):(8-12) to obtain the mixed raw material.

[0016] Optionally, municipal sludge, bentonite, and straw may be selected respectively, and the following may also be included: The municipal sludge with a moisture content of 80%~90% and a pH of 6.5~7.5 was selected, and after removing impurities, it was placed in a mixer and stirred at a speed of 150r / min~200r / min for 15 min~20 min. Bentonite with a particle size of 100-200 mesh and a purity of ≥90% was selected as a clay mineral activator. Straw with a particle size of 50-100 mesh and a moisture content of ≤10% was selected as biomass auxiliary raw material.

[0017] Another aspect of the present invention provides a sludge-derived biomass adsorbent, which adopts the preparation method of the sludge-derived biomass adsorbent described above.

[0018] The present invention provides a method for preparing sludge-derived biomass adsorbents. This method uses bentonite as a natural clay activator, replacing traditional strong acids and alkalis. It is non-corrosive, has simple post-treatment, and causes no secondary pollution. Simultaneously, it achieves the synergistic resource utilization of straw and sludge, realizing the concept of treating waste with waste. By subjecting the mixed raw materials to low-temperature pyrolysis and microwave activation, combined with straw assistance, the adsorbent possesses a well-developed pore structure and abundant active sites, exhibiting high adsorption capacity, good heavy metal fixation, satisfactory mechanical strength, and excellent regeneration performance. The mixed raw materials are widely available and inexpensive, the process steps are simple, energy consumption is low, and the preparation cost is reduced by 30%–40% compared to traditional chemical activation methods. The preparation method is simple, parameters are easily controlled, and the formed adsorbent can be directly adapted to existing water treatment equipment. Industrial scale-up is easy, and it has broad market application prospects. Attached Figure Description

[0019] Figure 1 This is a schematic flowchart illustrating a method for preparing a sludge-derived biomass adsorbent according to an embodiment of the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] Existing sludge production is large, with high water content, making it difficult to treat and dispose of. The sludge exhibits poor immobilization of heavy metals and other components, is prone to leaching, and lacks sufficient environmental safety, limiting its practical application. Furthermore, the preparation process is poorly adapted to the characteristics of the sludge, resulting in heterogeneous product structure, low mechanical strength, easy pulverization, and poor regeneration and recyclability. Current technologies struggle to achieve an effective balance between green production, low cost, high adsorption capacity, and high stability, making industrial scale-up extremely difficult.

[0022] In response to the above problems, such as Figure 1 As shown, one aspect of the present invention provides a method S100 for preparing a sludge-derived biomass adsorbent, the preparation method comprising: S110. Select municipal sludge, bentonite and straw respectively and mix them to obtain mixed raw materials.

[0023] Step S110 involves pre-treating the raw materials, and the specific process can be as follows: Municipal sludge with a moisture content of 80%–90% and a pH of 6.5–7.5 was selected. After removing impurities such as stones and plastics, the sludge was placed in a mixer and stirred at 150–200 r / min for 15–20 min to ensure a uniform sludge texture. Bentonite with a particle size of 100–200 mesh and a purity ≥90% was selected as a clay mineral activator. Straw with a particle size of 50–100 mesh and a moisture content ≤10% was selected as a biomass auxiliary raw material.

[0024] The sludge, bentonite, and straw are added to a mixer at a mass ratio of 100:(15-25):(8-12) and mixed for 20-30 minutes to obtain the mixed raw materials.

[0025] In this embodiment, bentonite is used as a natural clay activator to replace traditional strong acids and alkalis. It is non-corrosive, simple to process, and causes no secondary pollution. Simultaneously, it achieves the synergistic resource utilization of straw and sludge, realizing the concept of treating waste with waste. Pretreatment parameters for the three raw materials were limited to ensure consistency in raw material quality and process stability, providing a good raw material foundation for subsequent pyrolysis and activation, and improving product consistency and repeatability.

[0026] S120. The mixed raw materials are placed in a pyrolysis furnace and subjected to low-temperature pyrolysis at a temperature of 350℃~450℃ to obtain primary carbonized products.

[0027] Specifically, the mixed raw materials are placed in a pyrolysis furnace, nitrogen gas is introduced, the pyrolysis temperature is controlled at 350℃~450℃, the pyrolysis time is 40 min~60 min, and the pyrolysis heating rate is 5℃ / min~8℃ / min, and low-temperature pyrolysis is carried out to obtain the primary carbonized product.

[0028] In this embodiment, the mixed raw materials are subjected to low-temperature pyrolysis and the pyrolysis conditions are limited to ensure that the mixed raw materials are uniformly carbonized and pores are initially formed during the pyrolysis process, which provides a structural basis for subsequent microwave activation and avoids the problems of overheating or incomplete carbonization.

[0029] S130. The primary carbonized product is placed in a microwave activation furnace and microwave activated at a microwave power of 300 W to 500 W and an activation temperature of 500°C to 550°C to obtain the activated product.

[0030] Specifically, the primary carbonized product is fed into a microwave activation furnace, the microwave power is adjusted to 300 W ~ 500 W, the activation temperature is 500℃ ~ 550℃, the activation time is 30 min ~ 45 min, the microwave frequency is 2450 MHz ~ 2500 MHz, and nitrogen gas is continuously introduced during the activation process to obtain the activated product.

[0031] In this embodiment, the primary carbonized product is activated by microwave, and the conditions for microwave activation are limited. By utilizing the uniform heating characteristics of microwaves, pores are further opened and formed, the specific surface area and porosity are increased, the adsorption performance is enhanced, the activation efficiency is improved, and the energy consumption is reduced.

[0032] In addition, this embodiment innovatively uses low-temperature pyrolysis and microwave activation of mixed raw materials, which has the characteristics of low energy consumption and high efficiency, and solves the problem of uneven product performance.

[0033] For example, after obtaining the primary carbonized product, the preparation method further includes: After the activated product is naturally cooled to room temperature, it is washed 3-4 times with deionized water to remove surface residues; then it is placed in a drying oven at 105℃-110℃ for 2-3 hours to dry until the moisture content is ≤5%.

[0034] In this embodiment, a washing and drying step is added after microwave activation, which can effectively remove soluble impurities and byproducts that may remain during the activation process, improve product purity, and ensure the chemical stability and safety of the adsorbent.

[0035] S140. The activated product is pulverized, starch binder is added and deionized water is added and stirred to obtain a plastic material.

[0036] Specifically, the activated product is pulverized and passed through an 80-100 mesh sieve; 5%-8% by weight of starch binder is added; wherein, the starch binder is natural and environmentally friendly, with no secondary pollution. Deionized water is added and stirred to obtain the plastic material.

[0037] In this embodiment, the particle size of the activated product and the amount of binder are limited to ensure the plasticity and uniformity of the material. The addition of starch binder improves the molding strength and anti-pulverization ability of the adsorbent, which facilitates subsequent extrusion molding.

[0038] S150. The plastic material is extruded and dried to obtain a sludge-derived biomass adsorbent.

[0039] Specifically, the plastic material is fed into an extrusion molding machine and extruded into columnar granules at a molding pressure of 0.3 MPa to 0.5 MPa. The columnar granules have a diameter of 3 mm to 5 mm and a length of 8 mm to 12 mm.

[0040] The formed columnar particles are placed in a drying oven and dried at 100℃~105℃ for 1.5h~2h; then transferred to a muffle furnace and calcined at 200℃~250℃ for 30min~40min to enhance the mechanical strength of the particles, thus obtaining a sludge-derived biomass adsorbent.

[0041] In this embodiment, by controlling the pressure and shape of the extrusion molding, the adsorbent is formed into columnar particles, which improves the mechanical strength and fluid adaptability of the product, making it easier to fill and use in water treatment equipment. A segmented drying and calcination process is adopted, firstly, low-temperature drying removes free water, and then medium-temperature calcination enhances the stability of the particle structure, further improving the mechanical strength and water resistance of the adsorbent and extending its service life.

[0042] For example, after preparing the sludge-derived biomass adsorbent, it is necessary to perform performance testing on the prepared sludge-derived biomass adsorbent to ensure that its specific surface area is 600 m². 2 / g ~1000 m 2 / g, for Pb 2+ The adsorption capacity is ≥120mg / g, the heavy metal leaching rate is ≤0.08 mg / L, the compressive strength is ≥15 MPa, and the adsorption capacity retention rate after 5 regenerations is ≥85%. After passing the test, it should be sealed and stored in a dry and ventilated environment to avoid moisture.

[0043] The present invention provides a method for preparing a sludge-derived biomass adsorbent. This method uses bentonite as a natural clay activator, replacing traditional strong acids and alkalis. It is non-corrosive, has simple post-treatment, and causes no secondary pollution. Simultaneously, it achieves the synergistic resource utilization of straw and sludge, realizing the concept of treating waste with waste. By subjecting the mixed raw materials to low-temperature pyrolysis and microwave activation, combined with straw assistance, the adsorbent possesses a well-developed pore structure and abundant active sites, exhibiting high adsorption capacity, good heavy metal fixation, satisfactory mechanical strength, and excellent regeneration performance. The mixed raw materials are widely available and inexpensive, the process steps are simple, energy consumption is low, and the preparation cost is reduced by 30% to 40% compared to traditional chemical activation methods. The preparation method is simple, parameters are easily controlled, and the formed adsorbent can be directly adapted to existing water treatment equipment. Industrial scale-up is easy, and it has broad market application prospects.

[0044] Another aspect of the present invention provides a sludge-derived biomass adsorbent, which is prepared using the sludge-derived biomass adsorbent preparation method S100 described above. The specific steps of the preparation method S100 for this sludge-derived biomass adsorbent have been detailed above and will not be repeated here.

[0045] The sludge-derived biomass adsorbent provided by this invention has a well-developed pore structure and abundant active sites, high adsorption capacity, good heavy metal fixation effect, meets mechanical strength standards, and has excellent regeneration performance. It is suitable for the adsorption treatment of various water pollutants and has significant environmental and economic benefits. It uses bentonite as a natural clay activator to replace traditional strong acids and alkalis, is non-corrosive, has simple post-treatment, and no secondary pollution. At the same time, it realizes the synergistic resource utilization of straw and sludge, making it green and environmentally friendly.

[0046] The following examples illustrate the specific process of preparing the sludge-derived biomass adsorbent provided by this invention.

[0047] Example 1 Raw material pretreatment and mixing: Municipal sludge with a moisture content of 85% and a pH of 7.0 was selected, and after removing impurities, it was stirred at 180 r / min for 18 min; 150 mesh bentonite with a purity of 95% was selected; and 80 mesh corn stalks with a moisture content of 8% were selected. The sludge, bentonite, and corn stalks were mixed at a mass ratio of 100:20:10 and stirred for 25 min to obtain the mixed raw materials.

[0048] Low-temperature pyrolysis: The mixed raw materials are placed in a pyrolysis furnace, nitrogen is introduced, the temperature is raised at a rate of 6℃ / min, the temperature is raised to 400℃, and the pyrolysis is carried out at a constant temperature for 50min to obtain the primary carbonized product.

[0049] Microwave activation: The primary carbonization product is fed into a microwave activation furnace with a microwave power of 400W, an activation temperature of 520℃, a microwave frequency of 2450MHz, and an activation time of 35min. Nitrogen gas is purged throughout the process to obtain the activated product.

[0050] Post-treatment: After cooling, the activated product was washed three times with deionized water and dried at 108℃ for 2.5h until the moisture content was ≤5%.

[0051] Crushing and Preparing: The activated product is crushed through a 90-mesh sieve, 6% starch binder is added, and deionized water is added and stirred into a plastic material.

[0052] Molding and drying / calcination: The pellets were extruded into columnar particles with a diameter of 4 mm and a length of 10 mm under a pressure of 0.4 MPa; dried at 102℃ for 1.8 h and calcined at 220℃ for 35 min to obtain sludge-derived biomass adsorbent.

[0053] In this embodiment, the test results of the production capacity and performance of the sludge-derived biomass adsorbent are as follows: A single batch (based on 10 kg of mixed feedstock) can prepare approximately 6.8 kg of adsorbent, with a yield of approximately 68%. The measured specific surface area is 782 m² / g. (Regarding Pb...) 2+ The saturated adsorption capacity was 138 mg / g; the adsorption capacity for methylene blue was 215 mg / g. The leaching rates were 0.05 mg / L for Pb, 0.07 mg / L for Zn, and 0.04 mg / L for Cu. The compressive strength was 18.2 MPa; the attrition rate (after 1 hour of shaking) was 1.2%. After 5 adsorption-desorption cycles, the adsorption capacity retention rate was 88%.

[0054] Example 2 Raw material pretreatment and mixing: Municipal sludge with a moisture content of 80% and a pH of 6.5 was selected, and after impurities were removed, it was stirred at 150 r / min for 20 min; 100 mesh bentonite with a purity of 90% was selected; and 50 mesh wheat straw with a moisture content of 10% was selected. The sludge, bentonite, and straw were mixed at a mass ratio of 100:15:8 and stirred for 20 min to obtain the mixed raw materials.

[0055] Low-temperature pyrolysis: The mixed raw materials are fed into a pyrolysis furnace and nitrogen gas is introduced. The heating rate is 5℃ / min, and the mixture is pyrolyzed at a constant temperature of 350℃ for 60min to obtain primary carbonized products.

[0056] Microwave activation: Microwave activation furnace parameters: power 300W, temperature 500℃, frequency 2450MHz, activation time 45min, nitrogen gas continuously purged to obtain activated products.

[0057] Post-processing: After cooling, the activated product was washed four times with deionized water and dried at 105℃ for 3 hours.

[0058] Crushing and Preparing: The activated product is crushed through an 80-mesh sieve, 5% starch binder is added, and deionized water is added and stirred to form a plastic material.

[0059] Molding and drying / calcination: Extruded into columnar particles with a diameter of 3 mm and a length of 8 mm under a pressure of 0.3 MPa; dried at 100℃ for 2 h and calcined at 200℃ for 40 min to obtain the adsorbent.

[0060] In this embodiment, the test results of the production capacity and performance of the sludge-derived biomass adsorbent are as follows: A single batch (based on 10 kg of mixed feedstock) can prepare approximately 6.5 kg of adsorbent, with a yield of approximately 65%. The measured specific surface area is 652 m² / g. (Regarding Pb...) 2+ The saturated adsorption capacity was 121 mg / g; the adsorption capacity for methylene blue was 182 mg / g. The leaching rates were 0.07 mg / L for Pb, 0.09 mg / L for Zn, and 0.06 mg / L for Cu. The compressive strength was 15.6 MPa; the attrition rate (after 1 hour of shaking) was 1.8%. After 5 adsorption-desorption cycles, the adsorption capacity retention rate was 85%.

[0061] Example 3 Raw material pretreatment and mixing: Municipal sludge with a moisture content of 90% and a pH of 7.5 was selected, and after impurity removal, it was stirred at 200 r / min for 15 min; 200 mesh bentonite with a purity of 98% was selected; and 100 mesh rice straw with a moisture content of 5% was selected. The sludge, bentonite, and straw were mixed at a mass ratio of 100:25:12 and stirred for 30 min to obtain the mixed raw materials.

[0062] Low-temperature pyrolysis: Nitrogen gas is introduced into the pyrolysis furnace, the heating rate is 8℃ / min, and the pyrolysis is carried out at a constant temperature of 450℃ for 40min to obtain primary carbonized products.

[0063] Microwave activation: microwave power 500W, activation temperature 550℃, microwave frequency 2500MHz, activation time 30min, nitrogen gas is purged throughout the process to obtain the activated product.

[0064] Post-processing: After cooling, the activated product was washed three times with deionized water and dried at 110℃ for 2 hours.

[0065] Crushing and Preparing: The activated product is crushed through a 100-mesh sieve, 8% starch binder is added, and deionized water is added and stirred to form a plastic material.

[0066] Molding and drying / calcination: Extruded into columnar particles with a diameter of 5 mm and a length of 12 mm under a pressure of 0.5 MPa; dried at 105℃ for 1.5 h and calcined at 250℃ for 30 min to obtain the adsorbent.

[0067] In this embodiment, the test results of the production capacity and performance of the sludge-derived biomass adsorbent are as follows: A single batch (based on 10 kg of mixed feedstock) can prepare approximately 7.2 kg of adsorbent, with a yield of approximately 72%. The measured specific surface area is 945 m² / g. For Pb... 2+ The saturated adsorption capacity was 156 mg / g; the adsorption capacity for methylene blue was 248 mg / g. The leaching rates were 0.03 mg / L for Pb, 0.05 mg / L for Zn, and 0.03 mg / L for Cu. The compressive strength was 22.4 MPa; the attrition rate (after 1 hour of shaking) was 0.9%. After 5 adsorption-desorption cycles, the adsorption capacity retention rate was 91%.

[0068] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for preparing a sludge-derived biomass adsorbent, characterized in that, The preparation method includes: Municipal sludge, bentonite, and straw were selected and mixed separately to obtain a mixed raw material; The mixed raw materials are placed in a pyrolysis furnace and subjected to low-temperature pyrolysis at 350℃~450℃ to obtain primary carbonized products. The primary carbonized product was placed in a microwave activation furnace and microwave activated at a microwave power of 300 W to 500 W and an activation temperature of 500°C to 550°C to obtain the activated product. The activated product was pulverized, starch binder was added, and deionized water was added and stirred to obtain a plastic material. The plastic material is extruded and dried to obtain a sludge-derived biomass adsorbent.

2. The preparation method according to claim 1, characterized in that, After obtaining the activated product, the preparation method further includes: After cooling, the activated product is washed 3-4 times with deionized water, and then dried in a drying oven at 105℃-110℃ for 2-3 hours.

3. The preparation method according to claim 1, characterized in that, The mixed raw materials are placed in a pyrolysis furnace and subjected to low-temperature pyrolysis at 350℃~450℃ to obtain primary carbonized products, including: The mixed raw materials are placed in a pyrolysis furnace, nitrogen gas is introduced, the pyrolysis temperature is controlled at 350℃~450℃, the pyrolysis time is 40 min~60 min, and the pyrolysis heating rate is 5℃ / min~8℃ / min, and low-temperature pyrolysis is carried out to obtain the primary carbonized product.

4. The preparation method according to claim 1, characterized in that, The primary carbonized product is placed in a microwave activation furnace and microwave activated at a power of 300 W to 500 W and an activation temperature of 500°C to 550°C to obtain an activated product, comprising: The primary carbonized product is fed into a microwave activation furnace, and the microwave power is adjusted to 300 W~500 W, the activation temperature to 500℃~550℃, the activation time to 30 min~45 min, and the microwave frequency to 2450 MHz~2500 MHz. Nitrogen gas is continuously introduced during the activation process to obtain the activated product.

5. The preparation method according to claim 1, characterized in that, The activated product is pulverized, a starch binder is added, and deionized water is added and stirred to obtain a plastic material, comprising: The activated product is pulverized and passed through an 80-100 mesh sieve; Add 5% to 8% (by weight of the activated product) of starch binder; Add deionized water and stir to obtain the plastic material.

6. The preparation method according to claim 1, characterized in that, The process of extruding the plastic material includes: The plastic material is fed into an extrusion molding machine and extruded into columnar granules at a molding pressure of 0.3 MPa to 0.5 MPa.

7. The preparation method according to claim 6, characterized in that, Drying the plastic material includes: The formed columnar particles are placed in a drying oven and dried at 100℃~105℃ for 1.5h~2h. Transfer to a muffle furnace and bake at 200℃~250℃ for 30 min~40 min.

8. The preparation method according to claim 1, characterized in that, Municipal sludge, bentonite, and straw were selected and mixed separately to obtain a mixed raw material, including: The sludge, bentonite, and straw are mixed in a mass ratio of 100:(15-25):(8-12) to obtain the mixed raw material.

9. The preparation method according to claim 8, characterized in that, Municipal sludge, bentonite, and straw were selected respectively, and the following were also included: The municipal sludge with a moisture content of 80%~90% and a pH of 6.5~7.5 was selected, and after removing impurities, it was placed in a mixer and stirred at a speed of 150r / min~200r / min for 15 min~20 min. Bentonite with a particle size of 100-200 mesh and a purity of ≥90% was selected as a clay mineral activator. Straw with a particle size of 50-100 mesh and a moisture content of ≤10% was selected as biomass auxiliary raw material.

10. A sludge-derived biomass adsorbent, characterized in that, The method for preparing the sludge-derived biomass adsorbent according to any one of claims 1 to 9 is adopted.

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