CN110482811B

CN110482811B - Industrial sludge recycling treatment method

Info

Publication number: CN110482811B
Application number: CN201910815595.9A
Authority: CN
Inventors: 郭凯
Original assignee: Jiangsu Greway Environmental Protection Technology Co ltd
Current assignee: Jiangsu Greway Environmental Protection Technology Co ltd
Priority date: 2019-08-30
Filing date: 2019-08-30
Publication date: 2022-06-17
Anticipated expiration: 2039-08-30
Also published as: CN110482811A

Abstract

The embodiment of the invention discloses a resource treatment method of industrial sludge, which relates to the technical field of resources and environment, and comprises the following steps: sludge hydro-thermal treatment, preparation of carbon element supplement rich in humic acid, extrusion, shaping and drying, pyrolysis process and pyrolysis gas recycling. The industrial sludge recycling treatment method provided by the embodiment of the invention utilizes humic acid fermentation products of agricultural and forestry wastes as additives, the additives are mixed and shaped with sludge subjected to hydrothermal dehydration and detoxification according to a proportion, the dried sludge is put into an anaerobic pyrolysis furnace for anaerobic pyrolysis to prepare an adsorbent product capable of being used as a water treatment agent, volatile matters are collected and separated into condensate and noncondensable gas, and the condensate and the noncondensable gas are combusted by respective special combustors and then supplied to the pyrolysis furnace for energy, the process integrally forms a closed loop, the main energy does not need external energy supplement, and the secondary environmental protection problem is not brought.

Description

Industrial sludge recycling treatment method

Technical Field

The embodiment of the invention relates to the technical field of resources and environment, in particular to a resource treatment method for industrial sludge.

Background

The sewage in China is divided into industrial sewage and domestic sewage, and the discharge amount of the industrial sewage in China is increased from 246 hundred million tons to 305 hundred million tons in 2007 to 2016, and the discharge amount of the industrial sewage in China is developed according to the trend and can reach 350 million tons in 2020. The sludge is a terminal product generated in the sewage treatment process, and generally accounts for 3-5% of the volume of the sewage and 1-2% of the mass of the sewage.

Industrial wastewater sludge generally has the following characteristics: complex components, high content of toxic and harmful substances, dispersed sources and high yield. At present, the sludge treatment means adopted by domestic industrial enterprises mainly comprises gravity concentration, mechanical dehydration, natural drying, digestion + natural drying, deep drying + landfill, deep drying + incineration treatment and the like.

Wherein, the modes of gravity concentration, mechanical dehydration, natural drying, digestion and natural drying and the like are to stabilize the sludge, and the destination of the sludge is not indicated, namely the sludge is not really harmless.

The deep drying and landfill treatment mode is the treatment mode which is used for the longest time in China at the present stage. It has the following drawbacks: firstly, stabilization does not represent detoxification, and landfill only manages toxic substances in a centralized way and does not eradicate the toxic substances; secondly, the toxicity is easy to accumulate when the concentrated landfill is carried out; third, the toxic substances escape while naturally degrading and are inorganically emitted.

The deep drying and burning treatment mode is the best treatment mode for reduction. It has the following drawbacks: firstly, the problem of dioxin which cannot escape is always an important problem which troubles the development of sludge incineration like garbage incineration; secondly, the energy consumption is high, the heat value of the sludge treated by the incineration method cannot meet the incineration requirement, so that the normal incineration condition can be met by adding energy sources such as coal, natural gas and the like.

Disclosure of Invention

Therefore, the embodiment of the invention provides a resource treatment method for industrial sludge, which aims to solve the problems of the industrial sludge treatment method in the prior art.

In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:

according to a first aspect of the embodiments of the present invention, a method for recycling industrial sludge comprises the following steps:

the method comprises the following steps: quantitatively adding the sludge into a hydrothermal reaction kettle through a conveying device for hydrothermal treatment; fermenting agricultural and forestry wastes through a strain fermentation process to prepare a carbon element supplement rich in humic acid;

the sludge is subjected to hydrothermal treatment, and the hydrothermal treatment has the following effects:

dehydrating: the collision probability of sludge particles is increased under the action of high-temperature and high-pressure saturated steam, microbial cells are crushed, a colloid structure is damaged, and bound water content is remarkably reduced and is separated out to be free water.

② detoxification: under the environment conditions of high temperature and high pressure, a part of toxic substances (particularly volatile toxic substances) react to remove toxicity.

Dissolving reducible sugar: a certain amount of pores are formed in the low-temperature period of the soluble reducing sugar in the carbonization process, but the pores generated in the carbonization process are greatly collapsed with the subsequent increase of the temperature, and the collapse has the effect of reducing the adsorption value of a final product, so that the dissolution of the soluble sugar out of total solids by a hydrothermal method in the early stage is a necessary step for ensuring the quality of the product.

The carbon element supplement rich in humic acid is prepared by fermenting agricultural and forestry wastes through a strain fermentation process, wherein the fermentation process has the following effects: the carbon content can be increased, and the product yield can be improved; second, humic acid can be used as a microporous corrosive agent in the carbonization process, by H⁺Reaction with the C-bone chain structure produces micropores in the carbonized structure.

Step two: and (3) mixing the sludge subjected to the hydrothermal treatment in the step one with a carbon element supplement agent rich in humic acid according to the weight ratio of 1: (0.1-1), extruding the mixture into particles with the diameter of 5-50mm by using an extrusion forming machine after the mixture is uniformly mixed, and drying the particles to control the water content of the particles to be 5-25% after the extrusion forming is finished;

step three: putting the particles with the water content of 5-25% and the diameter of 5-50mm obtained in the step two into an anaerobic pyrolysis furnace for pyrolysis treatment to obtain a solid industrial sludge adsorbent and gaseous pyrolysis gas;

step four: and recycling the pyrolysis gas generated in the third step.

Further, the hydrothermal treatment conditions are as follows: the temperature is 140-220 ℃, the pressure is 1.2-3MPa, and the time is 2-4 h.

Further, in the step one, the specific process for preparing the carbon supplement rich in humic acid is as follows:

a. crushing straws, sawdust, branches, weeds, leaves or other agricultural and forestry wastes mainly containing lignin and cellulose into particles with the particle size of 5-80 mm; too large particles can cause incomplete fermentation and can not produce enough humic acid to influence the product quality; the problems of difficult ventilation, excessive fermentation and the like in the fermentation process can be caused by the excessively small particles, so that the carbon content of the product is reduced, the pore diameter of the adsorbent of the product is enlarged, and the quality of the product is influenced;

b. adding the crushed agricultural and forestry waste into a solid fermentation tank, and performing steam sterilization; the operation temperature of the steam sterilization is 110-140 ℃, and the time is 20-50 min; steam sterilization has three uses: one is to kill the original strains in the agricultural and forestry wastes so as to avoid influencing the subsequent fermentation; secondly, lignin, cellulose, hemicellulose and the like in the agricultural and forestry waste are hydrolyzed by steam, so that the value of the strain is increased conveniently during subsequent fermentation; thirdly, reducing sugar in the agricultural and forestry waste is dissolved, so that the reducing sugar can be consumed in the first time when the reducing sugar is subsequently inoculated to a strain for fermentation;

c. mixing the steam sterilized agricultural and forestry waste with mixed strains, and fermenting at 35 +/-2 ℃ for 7-30 days to obtain the carbon element supplement rich in humic acid, wherein the addition of the mixed strains is 5-20% of the amount of the steam sterilized agricultural and forestry waste.

Further, in step c, the mixed strain is selected from three or more strains selected from Bacillus subtilis, Bacillus amyloliquefaciens, Trichoderma longibrachiatum, Trichoderma koningii, Chaetomium globosum Kunze, Trichoderma reesei, Aspergillus carbonarius, Penicillium coriophilum, Anaxybacillus rupiens, Alcaligenes farecis, and Micrococcus terreus.

Further, in the third step, the pyrolysis treatment conditions are as follows: the temperature is 600 ℃ and 1000 ℃, the time is 10-60min, and the pressure is 0.01-0.5 MPa.

Further, the specific steps of the fourth step are as follows: cooling the pyrolysis gas generated in the third step by a heat exchanger, and then separating the pyrolysis gas in an oil-gas separation device; feeding the upper material combustible gas separated by the oil-gas separation device into a blast furnace gas burner for burning; the lower end material tar separated by the oil-gas separation device is sent into a tar burner for burning. 1m for each design³The blast furnace gas burner of combustible gas is correspondingly designed into a tar burner for burning 10-100mg of tar.

Through the technical scheme, combustible gases such as hydrogen, carbon monoxide, methane and other hydrocarbons in the pyrolysis gas enter the blast furnace gas burner to be burned so as to achieve the purpose of recycling, and tar in the pyrolysis gas is sent into the tar burner to be burned so as to achieve the purpose of recycling. The burner flame and the outer wall of the inner container of the anaerobic pyrolysis furnace can be directly contacted for heat exchange between the burner and the anaerobic pyrolysis furnace, and a flue gas heat exchange method can also be adopted for energy exchange.

Furthermore, the flue gas generated by combustion in the blast furnace gas burner and the tar burner respectively passes through the waste heat recovery system, the dust removal device and the gas purification device in sequence and is discharged after reaching the standard.

By the technical scheme, the waste heat recovery system can be used in devices needing heating, such as a heating furnace or a heat exchanger, and the like, so that the waste heat of the flue gas is fully utilized; the dust is separated from the flue gas by a dust removal device, and the dust removal device can be selected from a biological nano-film dust suppression device, a cloud dust suppression device, a cloth bag dust removal device, a cyclone dust removal device, a wet dust removal device, an electrostatic dust removal device and a desulfurization dust removal device; the polluted flue gas can be subjected to treatment work such as impurity removal and purification through the gas purification device; the flue gas passes through waste heat recovery system, dust collector and gas purification device respectively in proper order and through retrieving the recycle, reaches the standard of safe emission through purifying again, has also realized the abundant recycle of resource.

Further, in the third step, the anaerobic pyrolysis furnace is a sealed rotary kiln, a multi-hearth furnace or a tubular carbonization furnace.

The embodiment of the invention has the following advantages:

the industrial sludge recycling treatment method provided by the embodiment of the invention utilizes humic acid fermentation products of agricultural and forestry wastes as additives, the additives are mixed and shaped with sludge subjected to hydrothermal dehydration and detoxification according to a proportion, the dried sludge is put into an anaerobic pyrolysis furnace for anaerobic pyrolysis to prepare an adsorbent product capable of being used as a water treatment agent, volatile matters are collected and separated into condensate and noncondensable gas, and the condensate and the noncondensable gas are combusted by respective special combustors and then supplied to the pyrolysis furnace for energy, the process integrally forms a closed loop, the main energy does not need external energy supplement, and the secondary environmental protection problem is not brought.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.

The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so that those skilled in the art can understand and read the present invention, and do not limit the conditions for implementing the present invention, so that the present invention has no technical significance, and any structural modifications, changes in the ratio relationship, or adjustments of the sizes, without affecting the functions and purposes of the present invention, should still fall within the scope of the present invention.

Fig. 1 is a process flow chart of a method for recycling industrial sludge according to embodiment 1 of the present invention.

Detailed Description

The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The sludge in the embodiment is selected from a sludge centralized treatment project of a certain chemical industrial park, the treatment scale is 50t/d, the water content of the sludge is 80%, and the sludge also contains a certain amount of pollutants such as toluene, methanol, dichloroethane, acetaldehyde, paraldehyde, methyl mercaptan and the like.

A process flow diagram of the industrial sludge recycling treatment method is shown in figure 1, and the treatment method comprises the following steps:

the method comprises the following steps: sludge hydrothermal treatment and preparation of carbon element supplement rich in humic acid

Quantitatively adding the sludge into a hydrothermal reaction kettle through a conveying device for hydrothermal treatment; the conditions of the hydrothermal treatment are as follows: the temperature is 140 ℃, the pressure is 1.2MPa, and the time is 4 h; the water content of the sludge after the hydrothermal treatment is reduced to 45.32 percent after simple filtration;

the specific process for preparing the carbon element supplement rich in humic acid is as follows:

a. crushing straws, sawdust, branches, weeds, leaves or other agricultural and forestry wastes mainly containing lignin and cellulose into particles with the particle size of 10-15 mm;

b. adding the crushed agricultural and forestry waste into a solid fermentation tank, and performing steam sterilization; the operation temperature of the steam sterilization is 121 ℃, and the time is 35 min;

c. mixing the steam sterilized agricultural and forestry waste with mixed strains, and fermenting at 35 +/-2 ℃ for 7 days to obtain a carbon element supplement rich in humic acid, wherein the addition amount of the mixed strains is 10 percent of the amount of the steam sterilized agricultural and forestry waste; the mixed strain is selected from Bacillus subtilis, Bacillus subtilis subsp.subtilis, Bacillus amyloliquefaciens, Trichoderma longibrachiatum, Trichoderma koningii, Chaetomium globosum Kunze, Trichoderma reesei, Aspergillus carbonarius, Penicillium chrysophium, Anaoxydium rupiens, Alcaligenes faecalis and Micrococcus reum, wherein the inoculation amount of each strain is shown in the following table 1.

TABLE 1 EXAMPLE 1 inoculum size of each strain

Step two: extruding, shaping and drying

And (3) mixing the sludge subjected to the hydrothermal treatment in the step one with a carbon element supplement agent rich in humic acid according to the weight ratio of 1: 0.25, extruding the mixture into particles with the diameter of 15mm by using an extrusion forming machine after the mixture is uniformly mixed, and after the extrusion forming is finished, sending the particles into a rotary kiln for drying treatment to control the water content to be 15%;

step three: pyrolysis process

Putting the particles with the water content of 15% and the diameter of 15mm obtained in the step two into a dividing wall heat exchange type multi-hearth furnace with 4.5m and 6 layers for pyrolysis treatment to obtain a solid industrial sludge adsorbent and gaseous pyrolysis gas; the pyrolysis treatment conditions are as follows: the temperature is 600 ℃, the time is 52min, the pressure is 0.02-0.03MPa, and the rotating speed is controlled at 1.0-1.2 r/min;

step four: pyrolysis gas recycling

Carrying out heat exchange operation on the pyrolysis gas generated in the third step by a tubular heat exchanger, cooling, and then separating in an oil-gas separation device, wherein in the heat exchange process, air is taken out of the shell, and the heat exchanger adopts a vertical installation method; feeding the upper material combustible gas separated by the oil-gas separation device into a blast furnace gas combustor for combustion, wherein the volume ratio of air to the combustible gas in the combustion process is 6.01: 1; feeding the lower end material tar separated by the oil-gas separation device into a tar combustor for combustion; 1m for each design³The blast furnace gas burner of combustible gas is correspondingly designed to be a tar burner for burning 50mg of tar; and the flue gas generated by combustion in the blast furnace gas burner and the tar burner respectively passes through the waste heat recovery system, the dust removal device and the gas purification device in sequence and is discharged after reaching the standard.

The average pore volume of the industrial sludge adsorbent produced by the steps is 0.51mL/g, and the BET specific surface area is 812m²The adsorbent is used for treating agricultural enterprise wastewater with COD of 2400mg/L, chroma of 240 and TOC 393mg/L, and the removal rate of COD is high>87% removal rate of chroma>80 percent, the TOC removal rate is 53.3 to 63.5 percent, the adsorbent has high adsorption efficiency and can reach the commercial standard of the adsorbent, and no toxic substances in the raw sludge sample are detected in the adsorbent.

The industrial sludge recycling treatment method provided by the embodiment adopts three steps of detoxification treatment aiming at the relevant characteristics of industrial toxic sludge, and the steps are as follows: 1. degrading volatile organic matters by a hydrothermal process; 2. the carbonization process degrades the toxicity of the solid organic matter by causing elements such as C, H, O, N, S, Cl and the like in the solid organic matter to migrate to destroy the molecular structure of the solid organic matter; 3. the volatile components are subjected to special incineration to destroy the structure. The toxicity is reduced firstly, then the solid is carbonized, and finally the toxicity in the gas is solved. The method is used for carrying out thorough harmless treatment on the industrial toxic sludge.

In addition, in order to make the product have higher economic value, the product is selected to be a carbonized sludge adsorbent. That is, in the production process, it is necessary to ensure a microporous structure having an equivalent level of the adsorbent. The whole set of process plays an effective role in forming micropores in a triple mode and carries out reasonable protection, and the steps are as follows: 1. the hydrothermal process removes excess soluble sugars (as polysaccharides collapse pores that have formed); 2. the fermentation of humic acid ensures the source of a corrosive agent of the microporous structure; 3. the reasonable carbonization process ensures the formation of micropores.

Example 2

The industrial sludge resource treatment method comprises the following steps:

Quantitatively adding the sludge into a hydrothermal reaction kettle through a conveying device for hydrothermal treatment; the conditions of the hydrothermal treatment are as follows: the temperature is 210 ℃, the pressure is 3MPa, and the time is 2.5 h; the water content of the sludge after the hydrothermal treatment is reduced to 43.18 percent after simple filtration;

a. crushing straws, sawdust, branches, weeds, leaves or other agricultural and forestry wastes mainly containing lignin and cellulose to the particle size of 5-10 mm;

b. adding the crushed agricultural and forestry waste into a solid fermentation tank, and performing steam sterilization; the operation temperature of the steam sterilization is 110 ℃, and the time is 50 min;

c. mixing the steam sterilized agricultural and forestry waste with mixed strains, and fermenting at 35 +/-2 ℃ for 30 days to obtain a humic acid-rich carbon element supplement, wherein the addition of the mixed strains is 15 percent of the amount of the steam sterilized agricultural and forestry waste; the mixed strain is selected from Bacillus subtilis, Bacillus subtilis subsp.subtilis, Bacillus amyloliquefaciens, Trichoderma longibrachiatum, Trichoderma koningii, Chaetomium globosum Kunze, Trichoderma reesei, Aspergillus carbonarius, Penicillium coriophilum, Anaxybacillus rupiens, Alcaligenes faecalis, Micrococcus terreus, and the inoculation amount of each strain is shown in the following table 2.

Table 2 example 2 inoculum size of each strain

Bacterial species name	The percentage content is%
		Bacillus subtilis	10
Bacillus subtilis subsp.Subtilis	5
		Bacillus amyloliquefaciens	10
Trichoderma longibrachiatum	5
		Trichoderma koningii	10
Chaetomium globosum Kunze	15
		Trichoderma reesei	5
Aspergillus carbonarius	10
		Penicillium corylophilum	10
Anoxybacillus rupiensis	10
		Alcaligenes faecalis	5
Micrococcus terreus	5

Step two: extruding, shaping and drying

And (3) mixing the sludge subjected to the hydrothermal treatment in the step one with a carbon element supplement agent rich in humic acid according to the weight ratio of 1: 0.1, extruding the mixture into particles with the diameter of 5mm by using an extrusion forming machine after the mixture is uniformly mixed, and after the extrusion forming is finished, feeding the particles into a rotary kiln for drying treatment to control the water content to be 5%;

step three: pyrolysis process

Putting the particles with the water content of 5% and the diameter of 5mm obtained in the step two into a dividing wall heat exchange type multi-hearth furnace with 4.5m and 6 layers for pyrolysis treatment to obtain a solid industrial sludge adsorbent and gaseous pyrolysis gas; the pyrolysis treatment conditions are as follows: the temperature is 800 ℃, the time is 30min, the pressure is 0.10-0.12 MPa, and the rotating speed is controlled to be 1.0-1.2 r/min;

step four: pyrolysis gas recycling

The pyrolysis gas generated in the third step is subjected to heat exchange operation and temperature reduction through a tubular heat exchanger and then enters an oil-gas separation device for separation, wherein in the heat exchange process, air flows through a shell, and heat exchange is carried outThe device adopts a vertical installation method; feeding the upper material combustible gas separated by the oil-gas separation device into a blast furnace gas combustor for combustion, wherein the volume ratio of air to the combustible gas in the combustion process is 6.01: 1; feeding the lower end material tar separated by the oil-gas separation device into a tar combustor for combustion; 1m for each design³A combustible gas blast furnace gas burner is correspondingly designed with a tar burner for burning 96mg of tar; and the flue gas generated by combustion in the blast furnace gas burner and the tar burner respectively passes through the waste heat recovery system, the dust removal device and the gas purification device in sequence and is discharged after reaching the standard.

The average pore volume of the industrial sludge adsorbent produced by the steps is 0.57mL/g, and the BET specific surface area is 841m²The COD removal rate of the agricultural enterprise wastewater with the COD of 2130mg/L, the chroma of 210 and the TOC of 326mg/L treated by the adsorbent is>84% removal rate of chroma>75 percent, the TOC removal rate is 47.4 to 59.1 percent, the adsorbent has high adsorption efficiency and can reach the commercial standard of the adsorbent, and no toxic substances in the raw sludge sample are detected in the adsorbent.

Example 3

The industrial sludge resource treatment method comprises the following steps:

Quantitatively adding the sludge into a hydrothermal reaction kettle through a conveying device for hydrothermal treatment; the conditions of the hydrothermal treatment are as follows: the temperature is 180 ℃, the pressure is 2.6MPa, and the time is 3 h; the water content of the sludge after the hydrothermal treatment is reduced to 46.93 percent after simple filtration;

a. crushing straws, sawdust, branches, weeds, leaves or other agricultural and forestry wastes mainly containing lignin and cellulose to the particle size of 20-30 mm;

b. adding the crushed agricultural and forestry waste into a solid fermentation tank, and performing steam sterilization; the operation temperature of the steam sterilization is 140 ℃, and the time is 20 min;

c. mixing the steam sterilized agricultural and forestry waste with mixed strains, and fermenting at 35 +/-2 ℃ for 15 days to obtain a carbon element supplement rich in humic acid, wherein the addition of the mixed strains is 8 percent of the amount of the steam sterilized agricultural and forestry waste; the mixed strain is selected from Bacillus subtilis, Bacillus subtilis subsp.subtilis, Bacillus amyloliquefaciens, Trichoderma longibrachiatum, Trichoderma koningii, Chaetomium globosum Kunze, Trichoderma reesei, Aspergillus carbonarius, Penicillium coriophilum, Anaxybacillus rupiens, Alcaligenes faecalis, Micrococcus terreus, and the inoculation amount of each strain is shown in the following table 3.

TABLE 3 EXAMPLE 3 inoculum size of each strain

Bacterial species name	The percentage content is%
		Bacillus subtilis	5
Bacillus subtilis subsp.Subtilis	10
		Bacillus amyloliquefaciens	5
Trichoderma longibrachiatum	5
		Trichoderma koningii	10
Chaetomium globosum Kunze	10
		Trichoderma reesei	5
Aspergillus carbonarius	10
		Penicillium corylophilum	15
Anoxybacillus rupiensis	10
		Alcaligenes faecalis	5
Micrococcus terreus	10

Step two: extruding, shaping and drying

And (3) mixing the sludge subjected to the hydrothermal treatment in the step one with a carbon element supplement agent rich in humic acid according to the weight ratio of 1:1, uniformly mixing, extruding into particles with the diameter of 50mm by using an extrusion forming machine, and after extrusion forming is finished, feeding the particles into a rotary kiln for drying treatment to control the water content to be 25%;

step three: pyrolysis process

Putting the particles with the water content of 25% and the diameter of 50mm obtained in the step two into a dividing wall heat exchange type multi-hearth furnace with 4.5m and 6 layers for pyrolysis treatment to obtain a solid industrial sludge adsorbent and gaseous pyrolysis gas; the pyrolysis treatment conditions are as follows: the temperature is 1000 ℃, the time is 10min, the pressure is 0.48-0.50 MPa, and the rotating speed is controlled to be 1.0-1.2 r/min;

step four: pyrolysis gas recycling

Carrying out heat exchange operation on the pyrolysis gas generated in the third step by a tubular heat exchanger, cooling, and then separating in an oil-gas separation device, wherein in the heat exchange process, air is taken out of the shell, and the heat exchanger adopts a vertical installation method; feeding the upper material combustible gas separated by the oil-gas separation device into a blast furnace gas combustor for combustion, wherein the volume ratio of air to the combustible gas in the combustion process is 6.01: 1; feeding the lower end material tar separated by the oil-gas separation device into a tar combustor for combustion; 1m for combustion per design³The blast furnace gas burner of combustible gas is correspondingly designed into a tar burner for burning 10mg of tar; and the flue gas generated by combustion in the blast furnace gas burner and the tar burner respectively passes through the waste heat recovery system, the dust removal device and the gas purification device in sequence and is discharged after reaching the standard.

The average pore volume of the industrial sludge adsorbent produced by the steps is 0.59mL/g, and the BET specific surface area is 792m²Perg, the adsorbent is used for treating agricultural enterprise wastewater with COD of 1910mg/L, chroma of 197 and TOC of 295mg/L, and the COD removal rate is high>75% removal of chroma>70 percent, the removal rate of TOC is 45.5 to 57.0 percent, the adsorbent has high adsorption efficiency and can reach the commercial standard of the adsorbent, and no toxic substances in the raw sludge sample are detected in the adsorbent.

Although the invention has been described in detail with respect to the general description and the specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims

1. A method for recycling industrial sludge is characterized in that,

the processing method comprises the following steps:

the method comprises the following steps: quantitatively adding the sludge into a hydrothermal reaction kettle through a conveying device for hydrothermal treatment; fermenting agricultural and forestry waste by a strain fermentation process to prepare a carbon element supplement rich in humic acid;

step four: recycling the pyrolysis gas generated in the third step;

the fourth step comprises the following specific steps: cooling the pyrolysis gas generated in the third step by a heat exchanger, and then, separating the pyrolysis gas in an oil-gas separation device, wherein in the heat exchange process, air is in a shell shape, and the heat exchanger adopts a vertical installation method; feeding the upper material combustible gas separated by the oil-gas separation device into a blast furnace gas combustor for combustion, wherein the volume ratio of air to the combustible gas in the combustion process is 6.01: 1; feeding the lower end material tar separated by the oil-gas separation device into a tar combustor for combustion; 1m for each design³The blast furnace gas burner of combustible gas is correspondingly designed to be a tar burner for burning 50mg of tar;

in the first step, the specific process for preparing the humic acid-rich carbon supplement is as follows:

a. crushing straws, sawdust, branches, weeds, leaves or other agricultural and forestry wastes mainly containing lignin and cellulose into particles with the particle size of 5-80 mm;

b. adding the crushed agricultural and forestry waste into a solid fermentation tank, and performing steam sterilization; the operation temperature of the steam sterilization is 110-140 ℃, and the time is 20-50 min;

c. mixing the agriculture and forestry waste after steam sterilization with mixed strains, and fermenting for 7-30 days at (35 +/-2) DEG C to obtain the humic acid-rich carbon element supplement, wherein the addition amount of the mixed strains is 5% -20% of the amount of the agriculture and forestry waste after steam sterilization, and the mixed strains are selected from more than three strains of Bacillus subtilis, Bacillus subtilis subsp.

2. The method of claim 1 for recycling industrial sludge,

in the first step, the hydrothermal treatment conditions are as follows: the temperature is 140-220 ℃, the pressure is 1.2-3MPa, and the time is 2-4 h.

3. The method of claim 1 for recycling industrial sludge,

in the third step, the pyrolysis treatment conditions are as follows: the temperature is 600 ℃ and 1000 ℃, the time is 10-60min, and the pressure is 0.01-0.5 MPa.

4. The method of claim 1 for recycling industrial sludge,

and the flue gas generated by combustion in the blast furnace gas burner and the tar burner respectively passes through the waste heat recovery system, the dust removal device and the gas purification device in sequence and is discharged after reaching the standard.

5. The method of claim 1 for recycling industrial sludge,

in the third step, the anaerobic pyrolysis furnace is a sealed rotary kiln, a multi-hearth furnace or a tubular carbonization furnace.