Method for improving dewatering efficiency of antibiotic bacterial residue by sludge hydrothermal carbon and high-pressure filter pressing in cooperation

Abstract

This invention discloses a method for improving the dewatering efficiency of antibiotic bacterial residue through hydrothermal carbon conditioning combined with high-pressure filtration. The method involves placing sludge in a hydrothermal reaction vessel and carbonizing it at a constant temperature of 180℃–280℃ for 0.5–6 hours. The hydrothermal carbon from the hydrothermal carbonization reaction is then added to antibiotic bacterial residue with a moisture content of 85–98 wt.%, and after thorough mixing with hydrogen peroxide to break down the cell walls, high-pressure filtration is performed to obtain the dewatered antibiotic bacterial residue filter cake. The hydrothermal carbonization technology proposed in this invention requires no additional reagents, and the preparation temperature is lower compared to traditional carbon materials. Compared to traditional thermal treatment dewatering of antibiotic bacterial residue, only a very small proportion of hydrothermal carbon is needed to achieve highly efficient dewatering of the antibiotic bacterial residue, further reducing costs. Furthermore, this invention achieves both efficient dewatering of antibiotic bacterial residue and safe disposal and resource utilization of sludge waste.

Description

Technical fields:

[0001] This invention relates to the field of waste treatment technology, specifically to a method for improving the dewatering efficiency of antibiotic bacterial residue through sludge hydrothermal carbon synergistic high-pressure filtration. Background technology:

[0002] The main components of antibiotic fermentation residue include mycelium, intermediate metabolites, residual culture medium, organic solvents, and small amounts of residual antibiotics. Due to its high organic matter content, the residue can undergo secondary fermentation, severely impacting the environment. Furthermore, once residual antibiotics and resistance genes from the residue enter the environment, they can spread and accumulate within organisms, potentially leading to the emergence and spread of drug resistance in pathogens. This can render antimicrobial drugs ineffective, ultimately endangering human health. In practical engineering, the biggest limitation in antibiotic fermentation residue treatment is dehydration. The residue contains a large amount of extracellular polymers and other viscous substances, increasing its hydrophilicity and resulting in a high water content (>95%), making dehydration extremely difficult and increasing treatment complexity and cost. Therefore, breaking down extracellular polymers is considered key to efficient dehydration of the residue. Additionally, during mechanical dehydration, water is mainly discharged through seepage channels, but the organic matter in the residue is easily deformed under pressure, causing channel blockage. Therefore, constructing new seepage channels is necessary for effective dehydration. Summary of the Invention:

[0003] This invention solves the problems existing in the prior art and provides a method for improving the dewatering efficiency of antibiotic bacterial residue through sludge hydrothermal carbon synergistic high-pressure filtration. This invention uses sludge hydrothermal carbon conditioning combined with high-pressure filtration for dewatering antibiotic bacterial residue. Hydrogen peroxide is used to break down extracellular polymers and cell walls of the antibiotic bacterial residue. At the same time, carbon materials with a porous structure formed by sludge hydrothermal carbonization are used as the framework building block. Under high pressure, the released water is quickly discharged, thereby significantly improving the dewatering efficiency of antibiotic bacterial residue.

[0004] The purpose of this invention is to provide a method for improving the dewatering efficiency of antibiotic bacterial residue by sludge hydrothermal carbon synergistic high-pressure filtration, comprising the following steps: placing sludge in a hydrothermal reaction vessel and performing a constant-temperature hydrothermal carbonization reaction at 180℃~280℃ for 0.5~6h; adding the hydrothermal carbon from the hydrothermal carbonization reaction to antibiotic bacterial residue with a water content of 85~98wt.% to obtain a mixture, wherein the mass ratio of sludge hydrothermal carbon to antibiotic bacterial residue is 0.001~1:1; after the mixture is thoroughly mixed with hydrogen peroxide to break the cell walls, it is subjected to high-pressure filtration, wherein the pressure applied during filtration is 1~10MPa, thereby obtaining the dewatered antibiotic bacterial residue filter cake.

[0005] This invention utilizes porous carbon material formed by the hydrothermal carbonization of sludge to construct the framework of permeation channels, significantly reducing the moisture content of the antibiotic bacterial residue filter cake. This invention also employs hydrogen peroxide for pretreatment of the antibiotic bacterial residue to break down its cell walls, ensuring the effective discharge of bound water. Furthermore, while traditional plate and frame filter press technology can only achieve filtration pressures of <1 MPa, this invention utilizes high-pressure filter press technology, with a maximum pressure reaching 10 MPa, significantly improving dewatering efficiency.

[0006] Preferably, the sludge is selected from one or more of municipal sludge, dyeing and printing sludge, electroplating sludge, and papermaking sludge. More preferably, the sludge is municipal sludge.

[0007] Preferably, the hydrothermal carbonization reaction temperature is 200℃~260℃, and the reaction time is 2~6h.

[0008] Preferably, the antibiotic bacterial residue is selected from one or more of penicillin bacterial residue, oxytetracycline bacterial residue, gentamicin bacterial residue, cefoperazone bacterial residue, and streptomycin bacterial residue.

[0009] Preferably, the mass ratio of the sludge hydrothermal carbon to the antibiotic bacterial residue is 0.01 to 0.1:1.

[0010] Preferably, the mass ratio of hydrogen peroxide to antibiotic bacterial residue is 0.001 to 0.1:1.

[0011] Further preferably, the mass ratio of hydrogen peroxide to antibiotic bacterial residue is 0.01:1.

[0012] Preferably, the pressure applied during the pressure filtration is 6.5 to 10 MPa.

[0013] Preferably, the antibiotic bacterial residue has a moisture content of 95 wt.%.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] 1) This invention uses sludge hydrothermal carbon conditioning combined with high-pressure filtration to dewater antibiotic bacterial residue. It utilizes hydrogen peroxide to break down extracellular polymers and cell walls in the antibiotic bacterial residue, while using the porous carbon material formed by sludge hydrothermal carbonization as a framework to rapidly discharge the released water under high pressure, thereby significantly improving the dewatering efficiency of antibiotic bacterial residue.

[0016] 2) The hydrothermal carbonization technology for sludge requires no additional reagents and operates at a lower preparation temperature compared to traditional carbon materials, which helps reduce disposal costs. Furthermore, it causes less damage to the original skeletal structure of the material, making it more suitable for constructing water conveyance structures. Compared to traditional thermal treatment and dewatering of antibiotic bacterial residue, only a very small proportion of hydrothermal carbon from sludge is needed to achieve efficient dewatering of antibiotic bacterial residue, further reducing costs.

[0017] 3) Municipal sludge and other sludge wastes are also difficult to dewater, and traditional disposal methods can lead to serious environmental pollution. This invention simultaneously achieves the clean disposal and resource utilization of sludge. The filter cake obtained by adding sludge carbon and hydrogen peroxide to antibiotic bacterial residue can be directly incinerated / pyrolyzed without producing additional pollutants such as metal elements. In addition, due to the high nitrogen and water content of the sludge itself, nitrogen-doped porous carbon materials can be directly produced hydrothermally. Compared with other biomass carbon materials, these materials have a more complete pore structure and active groups, resulting in stronger water conveyance performance.

[0018] 4) The method of the present invention is simple, easy to implement, and low in cost, and can be further extended to the treatment of other organic wastes that are not easy to dehydrate. Detailed implementation method:

[0019] The following embodiments are further illustrations of the present invention, but not limitations thereof.

[0020] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention. Unless otherwise specified, the experimental materials and reagents used herein are commercially available products conventionally available in this technical field.

[0021] Example 1

[0022] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 4 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 0.02:1). After thorough mixing with hydrogen peroxide to break down the bacterial cell walls (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.01:1), the mixture was filtered under pressure of 10 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 32.7 wt%.

[0023] Comparative Example 1

[0024] Similar to Example 1, except that hydrogen peroxide was not added for cell wall disruption, and the moisture content of the filter cake was measured using a moisture analyzer, which showed that the moisture content of the filter cake was 66.8 wt%.

[0025] Comparative Example 2

[0026] Similar to Example 1, except that sludge hydrothermal carbon was not added as a framework component, and the moisture content of the filter cake was measured using a moisture analyzer, which showed that the moisture content of the filter cake was 65.4 wt%.

[0027] Comparative Example 3

[0028] Similar to Example 1, except that: no high-pressure filter press was used, the plate and frame filter press pressure was 0.5 MPa, and the moisture content of the filter cake was measured by a moisture analyzer, which showed that the moisture content of the filter cake was 58.1 wt%.

[0029] Comparative Example 4

[0030] Similar to Example 1, except that only hydrogen peroxide was used for cell disruption, no skeleton building blocks were added, and only plate and frame filtration was used. The moisture content of the filter cake was measured by a moisture analyzer, and the measured moisture content of the filter cake was 73.1 wt%.

[0031] As can be seen from the comparison of Example 1 and Comparative Examples 1-4, the antibiotic bacterial residue is dewatered by sludge hydrothermal carbon conditioning combined with high pressure filtration, and hydrogen peroxide is used to break down extracellular polymers and cell walls of the antibiotic bacterial residue. The sludge hydrothermal carbon, high pressure filtration and hydrogen peroxide have a synergistic effect.

[0032] Example 2

[0033] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 200℃ for 4 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 0.02:1). After thorough mixing and cell wall disruption with hydrogen peroxide (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.01:1), the mixture was pressure filtered at a pressure of 10 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 36.1 wt%.

[0034] Example 3

[0035] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 260℃ for 4 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 0.02:1). After thorough mixing with hydrogen peroxide to break down the bacterial cell walls (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.01:1), the mixture was filtered under pressure of 10 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 33.4 wt%.

[0036] Example 4

[0037] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 2 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 0.02:1). After thorough mixing with hydrogen peroxide to break down the bacterial cell walls (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.01:1), the mixture was filtered under pressure of 10 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 34.9 wt%.

[0038] Example 5

[0039] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 6 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 0.02:1). After thorough mixing with hydrogen peroxide to break down the bacterial cell walls (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.01:1), the mixture was filtered under pressure of 10 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 33.7 wt%.

[0040] Example 6

[0041] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 4 hours. The hydrothermal carbonized sludge was then added to oxytetracycline bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to oxytetracycline bacterial residue: 0.02:1). After thorough mixing with hydrogen peroxide to break down the bacterial cell walls (mass ratio of hydrogen peroxide to oxytetracycline bacterial residue: 0.01:1), the mixture was filtered under pressure of 10 MPa to obtain a dewatered oxytetracycline bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 37.6 wt%.

[0042] Example 7

[0043] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 4 hours. The hydrothermal carbonized sludge was then added to gentamicin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to gentamicin bacterial residue: 0.02:1). After thorough mixing and cell wall disruption with hydrogen peroxide (mass ratio of hydrogen peroxide to gentamicin bacterial residue: 0.01:1), the mixture was filtered under pressure of 10 MPa to obtain a dehydrated gentamicin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 36.0 wt%.

[0044] Example 8

[0045] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 4 hours. The hydrothermal carbonized sludge was then added to cefoperazone bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbonized sludge to cefoperazone bacterial residue was 0.02:1). After thorough mixing with hydrogen peroxide to break down the bacterial cell walls (mass ratio of hydrogen peroxide to cefoperazone bacterial residue was 0.01:1), the mixture was filtered under pressure of 10 MPa to obtain a dehydrated cefoperazone bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 33.5 wt%.

[0046] Example 9

[0047] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 4 hours. The hydrothermal carbonized sludge was then added to streptomycin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to streptomycin bacterial residue: 0.02:1). After thorough mixing and cell wall disruption with hydrogen peroxide (mass ratio of hydrogen peroxide to streptomycin bacterial residue: 0.01:1), the mixture was pressure filtered at a pressure of 10 MPa to obtain a dewatered streptomycin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 33.0 wt%.

[0048] Example 10

[0049] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 4 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 0.01:1). After thorough mixing and cell wall disruption with hydrogen peroxide (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.01:1), the mixture was pressure filtered at a pressure of 10 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 37.1 wt%.

[0050] Example 11

[0051] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 4 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 0.1:1). After thorough mixing and cell wall disruption with hydrogen peroxide (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.01:1), the mixture was pressure filtered at a pressure of 10 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 37.4 wt%.

[0052] Example 12

[0053] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 240℃ for 4 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 95 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 0.02:1). After thorough mixing with hydrogen peroxide to break down the bacterial cell walls (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.01:1), the mixture was filtered under pressure of 6.5 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 38.6 wt%.

[0054] The reaction conditions and filter cake moisture content of Examples 1-12 are shown in Table 1.

[0055] Table 1

[0056]

[0057]

[0058] Table 1 shows that, under the same treatment conditions, the dewatering efficiency of penicillin bacterial residue is the highest.

[0059] Example 13

[0060] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 180℃ for 6 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 85 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 0.001:1). After thorough mixing and cell wall disruption with hydrogen peroxide (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.001:1), the mixture was pressure filtered at a pressure of 1 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 69.5 wt%.

[0061] Example 14

[0062] Municipal sludge was placed in a hydrothermal reactor and carbonized at a constant temperature of 280℃ for 0.5 hours. The hydrothermal carbonized sludge was then added to penicillin bacterial residue with a moisture content of 98 wt.% (mass ratio of hydrothermal carbon to penicillin bacterial residue: 1:1). After thorough mixing with hydrogen peroxide to break down the bacterial cell walls (mass ratio of hydrogen peroxide to penicillin bacterial residue: 0.1:1), the mixture was filtered under pressure of 6.5 MPa to obtain a dehydrated penicillin bacterial residue filter cake. The moisture content of the filter cake was measured using a moisture analyzer and found to be 40.2 wt%.

[0063] This invention employs a combination of hydrothermal carbonization and high-pressure filtration to dewater antibiotic bacterial residue. Hydrogen peroxide is used to break down extracellular polymers and disrupt cell walls in the residue. Simultaneously, a porous carbon material formed during hydrothermal carbonization serves as the framework, rapidly releasing released water under high pressure, thus significantly improving the dewatering efficiency of the antibiotic bacterial residue. The hydrothermal carbonization technology requires no additional reagents and operates at a lower preparation temperature compared to traditional carbon materials. Compared to traditional thermal dewatering methods for antibiotic bacterial residue, only a very small proportion of hydrothermal carbon is needed to achieve highly efficient dewatering, further reducing costs. Furthermore, this invention achieves both efficient dewatering of antibiotic bacterial residue and safe disposal and resource utilization of sludge waste.

[0064] The above description of the embodiments is only for the purpose of helping to understand the technical solution and core idea of ​​the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for improving the dewatering efficiency of antibiotic bacterial residue by sludge hydrothermal carbonization and high-pressure filter pressing, characterized in that, The method comprises the following steps: placing sludge in a hydrothermal reaction container, performing constant-temperature hydrothermal carbonization reaction at 180-280 DEG C for 0.5-6 h, adding the hydrothermal carbonized sludge after the hydrothermal carbonization reaction into antibiotic dregs with a water content of 85-98 wt.% to obtain a mixture, the mass ratio of the hydrothermal carbonized sludge to the antibiotic dregs being 0.01-0.1:1, mixing the mixture and hydrogen peroxide, performing high-pressure pressure filtration after the wall of the mixture is broken, the pressure applied during the pressure filtration being 6.5-10 MPa, the mass ratio of the hydrogen peroxide to the antibiotic dregs being 0.001-0.1:1, and thus obtaining the antibiotic dregs filter cake after dehydration.

2. The method of claim 1, wherein, The sludge is selected from one or more of municipal sludge, printing and dyeing sludge, electroplating sludge and papermaking sludge.

3. The method according to claim 1 or 2, characterized in that, The hydrothermal carbonization reaction temperature is 200-260 DEG C, and the reaction time is 2-6 h.

4. The method of claim 1, wherein, The antibiotic dregs are selected from one or more of penicillin dregs, terramycin dregs, gentamicin dregs, cephalosporin dregs and streptomycin dregs.

5. The method of claim 1, wherein, The mass ratio of the hydrogen peroxide to the antibiotic dregs is 0.01:

1.

6. The method of claim 1, wherein, The water content of the antibiotic dregs is 95 wt.%.

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