CN113003911B - Low-temperature carbonization-assisted two-stage pyrolysis sludge thermochemical treatment system and method - Google Patents
Low-temperature carbonization-assisted two-stage pyrolysis sludge thermochemical treatment system and method Download PDFInfo
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- CN113003911B CN113003911B CN202110267407.0A CN202110267407A CN113003911B CN 113003911 B CN113003911 B CN 113003911B CN 202110267407 A CN202110267407 A CN 202110267407A CN 113003911 B CN113003911 B CN 113003911B
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/10—Treatment of sludge; Devices therefor by pyrolysis
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
- C10B53/00—Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
- C10B57/00—Other carbonising or coking processes; Features of destructive distillation processes in general
- C10B57/02—Multi-step carbonising or coking processes
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2303/00—Specific treatment goals
- C02F2303/10—Energy recovery
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/40—Valorisation of by-products of wastewater, sewage or sludge processing
Abstract
The invention discloses a sludge thermochemical treatment system and method of low-temperature carbonization assisted two-section pyrolysis, which comprises a low-temperature carbonization unit, a two-section pyrolysis unit and a product recovery unit, wherein the low-temperature carbonization technology is coupled with the pyrolysis technology, so that the treatment amount of sludge waste and the resource conversion rate are improved, the sludge enters a carbonization furnace for low-temperature carbonization, and the carbonized liquid sludge is dried, ground and granulated and then pyrolyzed in the two-section pyrolysis furnace, so that the energy conversion of a pyrolysis solution can be improved, and the harm of tar can be reduced; the products after pyrolysis are passed through a gas-solid separator, a tar removing device, a washer and a filter to carry out product separation and purification, thus ensuring the diversity of the products and the high energy value of the products. Energy level matching is achieved as far as possible in the product conversion process, energy conversion is improved to the maximum extent, system energy consumption and operation cost are reduced, system economy and stability are improved, and the method is green, economical and efficient.
Description
Technical Field
The invention belongs to the technical fields of energy chemical industry, waste disposal, resource utilization and the like, and particularly relates to a sludge thermochemical treatment system and method based on low-temperature carbonization assisted two-stage pyrolysis.
Background
Sludge refers to sludge produced in urbanization construction related to production and living, and mainly municipal sewage sludge. Handle municipal sludge, can alleviate the environmental problem that mud brought on the one hand, on the other hand also can obtain economic benefits: the bulk nutrients in sewage sludge can serve as a good source of plant nutrients, while the organic components can provide beneficial soil conditioning properties. The use of sewage sludge on land is becoming more common as valuable components can be recovered, application of sludge to soil can recycle nutrients, and the need for commercial fertilizers in the field can be eliminated. More and more studies show that the traditional sludge disposal methods such as landfill, composting, throwing into the sea and the like are no longer feasible. The sludge used as the agricultural fertilizer is affected by metals and pathogens, and the excessive use of the sludge can cause the content of heavy metal ions in the soil to exceed the standard, so that the heavy metal ions are transmitted through a plant-human body food chain to harm the human health, and simultaneously, the fertility of the soil can be reduced to worsen the surrounding environment. The water content in the landfill sludge is high, and the leachate can pollute the underground water source; the landfill sites need to be treated by certain technologies, and the landfill sites are selected to be special, so that the landfill is not practical for countries with small land available area. The thrown-into-sea sludge may contain pathogenic bacteria, which cause certain harm to marine organisms; the sludge discharge area needs a larger tidal current water volume to play a self-purification role, and the amount of the thrown-into-sea sludge is limited by the size of ocean current.
With the development of research, thermochemical treatment has become an effective way of sludge treatment. The thermochemical method is used for treating the sludge, so that the treatment amount of the sludge can be effectively increased, and the part with higher c content in the sludge can be converted into energy and fuel for recycling. Thermochemical treatment processes were initially directed to treating high calorific value, low moisture, low volatile coal, and subsequently developed thermochemically treated sludges on the thermochemical treatment of coal and biomass. The H/C ratio of the sludge is higher than that of other organic matters, so that the sludge can be used as an organic matter raw material for thermochemical treatment. The thermochemical treatment technology of the sludge comprises pyrolysis, wet oxidation, supercritical water gasification, combustion and the like, but most thermochemical treatment systems of the sludge at present are supported by a single technology, the product acquisition is single, and the resource utilization of the sludge is low.
Therefore, there is a need for a new sludge thermochemical treatment system and method that can couple various sludge thermochemical technologies to achieve economic and ecological benefits. The sludge reduction is realized, the poly-generation of products is ensured, and the harmless treatment and the resource utilization rate of the sludge are improved.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a low-temperature carbonization-assisted two-stage pyrolysis sludge thermochemical treatment system and a method, the system is reasonable in design and high in operation stability, and resource utilization of sludge is guaranteed by coupling various thermochemical technologies.
In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose:
the invention discloses a sludge thermochemical treatment system adopting low-temperature carbonization assisted two-stage pyrolysis, which comprises a low-temperature carbonization unit, a two-stage pyrolysis unit and a product recovery unit;
the low-temperature carbonization unit comprises a preheater, a carbonization furnace, a heat exchanger and a condenser; the outlet of the preheater is connected with the inlet of the carbonization furnace through a fourth valve, the outlet of the carbonization furnace is connected with the inlet of the heat exchanger through a fifth valve, the heat exchanger is provided with two outlets, the first outlet is connected with the preheater, and the second outlet is connected with the inlet of the condenser through a sixth valve;
the two-section pyrolysis unit comprises a dryer, a grinding machine, nitrogen supply equipment and a two-section pyrolysis furnace, wherein the outlet of a condenser is connected with the inlet of the dryer through a back pressure valve, the outlet end of the dryer is connected with the inlet end of the grinding machine through a pipeline, a pressure reducing device is arranged on the pipeline, the outlet of the grinding machine is connected with the first inlet of the two-section pyrolysis furnace, and the nitrogen supply equipment is connected with the second inlet of the two-section pyrolysis furnace through a valve seven;
the product recovery unit comprises a gas-solid separator, a tar collecting device, a washer, a filter and a gas collector, an outlet of the two-stage pyrolysis furnace is connected to an inlet of the gas-solid separator through a valve eight, an outlet of the gas-solid separator is connected with an inlet end of the tar collecting device, an outlet end of the tar collecting device is sequentially connected with the washer and the filter, and the filter is connected with the gas collector through a valve nine.
Preferably, the system also comprises a sludge pretreatment unit arranged at the front end of the low-temperature carbonization unit, wherein the sludge pretreatment unit comprises a sludge storage bin, a cutting machine and a dewatering machine; the outlet of the sludge storage bin is connected with the inlet of the cutting machine through a first valve, the outlet of the cutting machine is connected with the inlet of the dehydrator through a second valve, and the outlet of the dehydrator is connected with the inlet of the preheater through a third valve.
Further preferably, a first conveying device is arranged on a pipeline connecting the sludge storage bin and the cutting machine; a second conveying device is arranged on a pipeline connecting the cutting machine and the dehydrator; a third conveying device is arranged on a pipeline connecting the dehydrator and the heat exchanger; a fourth conveying device is arranged on a pipeline connecting the pressure reducing device and the grinding machine; and a fifth conveying device is arranged on a pipeline connecting the grinding machine and the two-section pyrolysis furnace.
Further preferably, the first conveying device, the second conveying device and the third conveying device adopt pumps, and the fourth conveying device and the fifth conveying device adopt screw conveyors.
Preferably, for sufficient separation, the tar collecting devices are connected in series, the inlet end of the tar collecting device arranged at the head is connected with the outlet end of the gas-solid separator, and the outlet end of the tar collecting device arranged at the tail is connected with the scrubber.
Preferably, the two-stage pyrolysis furnace adopts a tubular reactor or a kettle reactor, and the heating equipment adopted in the two-stage pyrolysis furnace is an electromagnetic heater or a resistance heater.
Preferably, the gas-solid separator adopts a cyclone separator, the scrubber is selected from a Venturi scrubber or a wet scrubber, and the filter is selected from a paper filter or a water filter.
The invention also discloses a sludge treatment method based on the low-temperature carbonization-assisted two-stage pyrolysis sludge thermochemical treatment system, which comprises the following steps of:
1) the sludge enters a low-temperature carbonization unit for low-temperature carbonization treatment, and the carbonized sludge is converted into a cracking solution;
2) the pyrolysis liquid flows through the heat exchanger to preheat the dewatered sludge which does not enter the heat exchanger, and the pyrolysis liquid after energy recovery and utilization flows into a condenser to be condensed;
3) the condensed sludge lysate flows into a dryer for drying, and the dried mud cake is sent into a grinder for grinding and granulation;
4) feeding the granulated sludge ground in the step 3) into a two-section pyrolysis furnace for pyrolysis, and simultaneously feeding nitrogen in nitrogen supply equipment into the two-section pyrolysis furnace for purging and deoxidizing;
5) and (3) separating the pyrolysis product treated in the step 4) by a gas-solid separator to obtain coke, removing the coke from the residual gas-phase product by a tar collecting device, washing by a washer, filtering by a filter, and collecting by a gas collector to obtain clean synthesis gas.
Preferably, the operation of pretreating the sludge before the step 1) comprises the steps of cutting and dehydrating the sludge.
Preferably, in the step 4), the pyrolysis temperature is 500-800 ℃.
Compared with the prior art, the invention has the following beneficial effects:
the invention discloses a low-temperature carbonization-assisted two-section pyrolysis sludge thermochemical treatment system and a method, wherein the device system comprises a low-temperature carbonization unit, a two-section pyrolysis unit and a product recovery unit, the low-temperature carbonization technology and the pyrolysis technology are coupled, sludge enters a carbonization furnace for low-temperature carbonization, the sludge viscosity is reduced, the sludge dewatering capacity is improved, the energy utilization efficiency can be further improved through heat exchange recovery, liquid sludge after low-temperature carbonization does not contain toxic gas, the secondary pollution is small, the carbonized cracking liquid reflows to be used for preheating the sludge, the sludge is fully cracked through low-temperature carbonization, the sludge waste treatment amount and the resource conversion rate are improved, the energy consumption is about 50% lower than that of the traditional drying technology, and is about 80% lower than that of the sludge directly burned. And the low-temperature carbonization process stabilizes the carbon content in the sludge and is beneficial to the acquisition of high-energy products. The carbonized liquid sludge is dried, ground and granulated, and then pyrolyzed in a two-section pyrolysis furnace, so that the energy conversion of the pyrolysis liquid can be improved, the harm of tar can be reduced, and the arrangement cost of gasification and purification equipment can be reduced. The products after pyrolysis are passed through a gas-solid separator, a tar removing device, a washer and a filter to carry out product separation and purification, thus ensuring the diversity of the products and the high energy value of the products. Energy level matching is achieved as far as possible in the product conversion process, energy conversion is improved to the maximum extent, system energy consumption and operation cost are reduced, system economy and stability are improved, and the method is green, economical and efficient. The organic matter of the sludge is decomposed under the action of heat, the colloid structure is destroyed, the viscosity is reduced, the operation reliability of the whole system is high, the power consumption of the sludge conveyor is reduced, and meanwhile, the multiple products are recovered and the cleaning equipment works in series, so that the cleaning efficiency of the synthesis gas is ensured. Reaction equipment, conveying equipment and product cleaning equipment are flexibly selected, the stability of the system is improved, system optimization is realized, harmless treatment and resource utilization of sludge are effectively improved, certain conditions are provided for development of sludge thermochemical treatment technology, certain conditions are provided for treatment and product recovery of municipal sludge through the design of the whole system, and the industrialization process of sludge thermochemical treatment is accelerated.
Drawings
Fig. 1 is a schematic structural diagram of a sludge thermochemical treatment system for two-stage pyrolysis assisted by low-temperature carbonization according to the present invention.
Wherein: 1 is a sludge storage bin; 2, conveying equipment I; 3 is a valve I; 4, a cutting machine; 5 is a second conveying device; 6 is a valve II; 7 is a dehydrator; 8, conveying equipment III; 9 is a valve III; 10 is a preheater; 11 is a valve IV; 12 is a carbonization furnace; 13 is a valve five; 14 is a heat exchanger; 15 is a valve six; 16 is a condenser; 17 is a back pressure valve; 18 is a drier; 19 is a pressure reducing device; 20, conveying equipment IV; 21 is a grinder; 22 is a conveying device five; 23 is a nitrogen gas supply device; 24 is a seventh valve, 25 is a two-stage pyrolysis furnace, 26 is an eighth valve, 27 is a gas-solid separator, 28 is a tar collecting device, 29 is a scrubber, 30 is a filter, and 31 is a ninth valve; and 32 is a gas collector.
Detailed Description
In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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.
It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
The invention is described in further detail below with reference to the accompanying drawings:
referring to fig. 1, the sludge thermochemical treatment system adopting low-temperature carbonization assisted two-stage pyrolysis provided by the invention comprises a low-temperature carbonization unit, a two-stage pyrolysis unit and a product recovery unit.
The low temperature carbonization unit includes pre-heater 10, carbonization furnace 12, heat exchanger 14, condenser 16, back pressure valve 17, valve four 11, five 13 of valve and six 15 of valve, the export of hydroextractor 7 passes through conveying equipment three 8 with the entry of heat exchanger 14, three 9 of valve link to each other with the pipeline, four 11 and tube coupling are passed through with carbonization furnace 12's import in the export of pre-heater 10, five 13 of valve and pipeline link to each other are passed through with heat exchanger 14's import in the export of carbonization furnace 12, heat exchanger 14's export links to each other with pre-heater 10 and the entry through six 15 of valve and condenser 16 respectively, condenser 16's exit is equipped with back pressure valve 17, and link to each other with two segmentation pyrolysis unit.
The two-stage pyrolysis unit comprises a dryer 18, a pressure reducer 19, a grinder 21, a nitrogen supply device 23, a two-stage pyrolysis furnace 25, a conveying device four 20, a conveying device five 22, a valve seven 24 and a valve eight 26, wherein the pressure reducer 19 is arranged at an outlet of the dryer 18, the outlet of the grinder 21 is connected with an inlet of the grinder 21 through the conveying device four 20, an outlet of the grinder 21 is connected to an inlet of the two-stage pyrolysis furnace 25 through the conveying device five 22, the nitrogen supply device 23 is connected with another inlet of the two-stage pyrolysis furnace 25 through the valve seven 24, and an outlet of the two-stage pyrolysis furnace 25 is connected to a product recovery unit through the valve eight 26.
The product recovery unit comprises a gas-solid separator 27, a tar collecting device 28, a scrubber 29, a filter 30, a valve nine 31 and a gas collector 32, wherein the inlet of the gas-solid separator 27 is connected with the two-stage pyrolysis unit through a valve eight 26, the outlet of the gas-solid separator 27 is connected with the tar collecting device 28, the tar collecting device 28 is connected to the scrubber 29 through a pipeline, the scrubber 29 is connected with the filter 30 through a pipeline, and the filter 30 is connected with the gas collector 32 through a pipeline and a valve eight 26.
Preferably, a sludge pretreatment unit is arranged at the front end of the low-temperature carbonization unit and comprises a sludge storage bin 1, a cutting machine 4, a dewatering machine 7, a first conveying device 2, a second conveying device 5, a third conveying device 8, a first valve 3, a second valve 6 and a third valve 9, an outlet of the sludge storage bin 1 is connected with an inlet of the cutting machine 4 through the first conveying device 2, the first valve 3 and a pipeline, and an inlet of the dewatering machine 7 is connected with an outlet of the cutting machine 4 through the second conveying device 5, the second valve 6 and the pipeline.
Preferably, the outlet of the sludge storage bin 1 is connected with the inlet of the cutting machine 4 through a first conveying device 2 and a first valve 3, and the inlet of the dewatering machine 7 is connected with the inlet of the cutting machine 4 through a second conveying device 5 and a second valve 6.
Preferably, the outlet of the sludge pretreatment unit is connected with the inlet of the low-temperature carbonization unit, the outlet of the sludge pretreatment unit is connected with the inlet of the preheater 10 through the third conveying device 8 and the third valve 9 and a pipeline, the outlet of the preheater 10 is connected with the inlet of the carbonization furnace 12 through the fourth valve 11 and a pipeline, and the outlet of the carbonization furnace 12 is connected with the inlet of the heat exchanger 14 through the fifth valve 13 and a pipeline.
Preferably, the outlet of the heat exchanger 14 is directly connected to the preheater 10 and to the inlet of the condenser 16 through a valve six 15, respectively, the outlet of the condenser 16 being provided with a back pressure valve 17.
Preferably, the outlet of the low-temperature carbonization unit is connected to the inlet of the two-stage pyrolysis unit, the outlet of the low-temperature carbonization unit is connected to the inlet of the dryer 18, the outlet of the dryer 18 is provided with a pressure reducer 19, and is connected to the inlet of the grinder 21 through a conveying device four 20, the two-stage pyrolysis furnace 25 is provided with two inlets, the outlet of the grinder 21 is connected to one inlet of the two-stage pyrolysis furnace 25 through a conveying device five 22, and the nitrogen gas supply device 23 is connected to the other outlet of the two-stage pyrolysis furnace 25 through a valve seven 24.
Preferably, the outlet of the two-stage pyrolysis unit is connected with the inlet of the product recovery unit, the outlet of the two-stage pyrolysis unit is connected with the inlet of the gas-solid separator 27 through a valve eight 26, the outlet of the gas-solid separator 27 is connected with the inlet of the tar collecting device 28, the outlet of the tar collecting device 28 is connected to the inlet of the scrubber 29 through a pipeline, the outlet of the scrubber 29 is connected with the inlet of the filter 30 through a pipeline, and the outlet of the filter 30 is connected with the valve eight through a pipeline.
The tar collecting devices 28 are connected in series, the inlet end of the tar collecting device arranged at the head is connected with the outlet end of the gas-solid separator 27, and the outlet end of the tar collecting device arranged at the tail is connected with the scrubber 29.
Preferably, the first conveying device 2, the second conveying device 5 and the third conveying device 8 can be selected from common pumps, and the fourth conveying device 20 and the fifth conveying device 22 can be selected from screw conveyors.
Preferably, the low-temperature carbonization furnace 12 and the two-stage pyrolysis furnace 25 may be a tubular reactor or a tank reactor, and the heating device used is an electromagnetic heater or a resistance heater.
Preferably, the gas-solid separator 27 may be a cyclone separator, the scrubber 29 may be a venturi scrubber or a wet scrubber, and the filter 30 may be a paper filter or a water filter.
Referring to fig. 1, the municipal sludge thermochemical treatment method using low-temperature carbonization-assisted two-stage pyrolysis according to the present invention includes the following steps:
sludge of a sewage plant enters a storage bin 1 for storage, is conveyed to a cutting machine 4 for cutting through a first conveying device 2, and is conveyed to a dehydrator 7 for dehydration through a second conveying device 5;
the dewatered sludge enters a preheater 10 through a third conveying device 8 for preheating, and the preheated sludge flows into a carbonization furnace 12 for low-temperature carbonization;
the carbonized sludge is changed into a cracking solution, the carbonized sludge flows through the heat exchanger 14 to preheat the dehydrated sludge which does not enter the heat exchanger 10, and the energy-recycled cracking solution flows into the condenser 16 to be condensed;
the condensed sludge lysate flows into a dryer 18 for drying, and the dried mud cake is sent into a grinder 21 for grinding and granulation through a fourth conveying device 20;
and feeding the ground granular sludge into a two-section pyrolysis furnace 25 through a fifth conveying device 22 via an inlet for pyrolysis, and feeding nitrogen in a nitrogen supply device 23 into the pyrolysis furnace for purging and deoxidizing.
After the sludge pyrolysis liquid after low-temperature carbonization is subjected to two-stage pyrolysis, the pyrolysis product is separated by a gas-solid separator 27 to obtain coke, the residual gas-phase product is decoked by a tar collecting device 28, washed by a washer 29, filtered by a filter 30 and captured by a gas collector 32 to obtain clean synthesis gas.
The invention discloses a low-temperature carbonization-assisted two-section pyrolysis sludge thermochemical treatment system, which comprises the following steps:
the sludge carbonization technology and the pyrolysis technology are coupled, so that the product has diversity, and the sludge treatment amount and the resource conversion rate are improved. The liquid sludge after low-temperature carbonization does not contain toxic gas, and has small secondary pollution. The carbonized cracking liquid is refluxed for sludge preheating, and the energy recycling is improved. The low-temperature carbonization leads the sludge to be fully cracked, improves the mechanical dehydration capability of the sludge, and has about 50 percent lower energy consumption than the traditional drying technology and about 80 percent lower energy consumption than the direct incineration. And the low-temperature carbonization process stabilizes the carbon content in the sludge and is beneficial to obtaining high-energy products.
The two-stage pyrolysis improves the energy conversion efficiency of the sludge pyrolysis liquid and reduces the generation of tar, thereby reducing the arrangement cost of gasification purification equipment. The organic matter of the sludge is decomposed under the action of heat, the colloid structure is destroyed, the viscosity is reduced, the operation reliability of the whole system is high, the power consumption of the sludge conveyor is reduced, and meanwhile, the multiple products are recovered and the cleaning equipment works in series, so that the cleaning efficiency of the synthesis gas is ensured. Reaction equipment, conveying equipment and product cleaning equipment are flexibly selected, the stability of the system is improved, system optimization is realized, harmless treatment and resource utilization of sludge are effectively improved, and reference information is provided for the industrialization process of the sludge thermochemistry treatment technology.
In summary, the municipal sludge thermochemical treatment system adopting low-temperature carbonization-assisted two-stage pyrolysis disclosed by the invention has the following advantages
The sludge carbonization technology and the pyrolysis technology are coupled, so that the product has diversity, and the sludge treatment amount and the resource conversion rate are improved.
The liquid sludge after low-temperature carbonization does not contain toxic gas, and has small secondary pollution. The carbonized cracking liquid is refluxed for sludge preheating, and the energy recycling is improved.
The low-temperature carbonization leads the sludge to be fully cracked, improves the mechanical dehydration capability of the sludge, and has about 50 percent lower energy consumption than the traditional drying technology and about 80 percent lower energy consumption than the direct incineration. And the low-temperature carbonization process stabilizes the carbon content in the sludge and is beneficial to obtaining high-energy products.
The two-stage pyrolysis improves the energy conversion efficiency of the sludge pyrolysis liquid and reduces the generation of tar, thereby reducing the arrangement cost of gasification purification equipment.
The organic matter of the sludge is decomposed under the action of heat, the colloid structure is destroyed, the viscosity is reduced, the operation reliability of the whole system is high, the power consumption of the sludge conveyor is reduced, and meanwhile, the multiple products are recovered and the cleaning equipment works in series, so that the cleaning efficiency of the synthesis gas is ensured.
The reaction equipment, the conveying equipment and the product cleaning equipment used by the system are flexibly selected, the stability of the system is improved, the system optimization is realized, the harmless treatment and resource utilization of the sludge are effectively improved, and certain conditions are provided for the development of the sludge thermochemical treatment technology.
The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.
Claims (10)
1. A sludge thermochemical treatment system adopting low-temperature carbonization assisted two-stage pyrolysis is characterized by comprising a low-temperature carbonization unit, a two-stage pyrolysis unit and a product recovery unit;
the low-temperature carbonization unit comprises a preheater (10), a carbonization furnace (12), a heat exchanger (14) and a condenser (16); the outlet of the preheater (10) is connected with the inlet of the carbonization furnace (12) through a valve IV (11), the outlet of the carbonization furnace (12) is connected with the inlet of the heat exchanger (14) through a valve V (13), the heat exchanger (14) is provided with two outlets, the first outlet is connected with the preheater (10), and the second outlet is connected with the inlet of the condenser (16) through a valve VI (15);
the two-stage pyrolysis unit comprises a dryer (18), a grinder (21), nitrogen supply equipment (23) and a two-stage pyrolysis furnace (25), wherein an outlet of a condenser (16) is connected with an inlet of the dryer (18) through a backpressure valve (17), an outlet end of the dryer (18) is connected with an inlet end of the grinder (21) through a pipeline, a pressure reducing device (19) is arranged on the pipeline, an outlet of the grinder (21) is connected with a first inlet of the two-stage pyrolysis furnace (25), and the nitrogen supply equipment (23) is connected with a second inlet of the two-stage pyrolysis furnace (25) through a valve seven (24);
the product recovery unit comprises a gas-solid separator (27), a tar collecting device (28), a scrubber (29), a filter (30) and a gas collector (32), an outlet of the two-stage pyrolysis furnace (25) is connected to an inlet of the gas-solid separator (27) through a valve eight (26), an outlet of the gas-solid separator (27) is connected with an inlet end of the tar collecting device (28), an outlet end of the tar collecting device (28) is sequentially connected with the scrubber (29) and the filter (30) and is connected with the filter (30), and the filter (30) is connected with the gas collector (32) through a valve nine (31).
2. The sludge thermochemical treatment system of two-stage pyrolysis assisted by low-temperature carbonization according to claim 1, further comprising a sludge pretreatment unit disposed at the front end of the low-temperature carbonization unit, wherein the sludge pretreatment unit comprises a sludge storage bin (1), a cutter (4) and a dehydrator (7); the outlet of the sludge storage bin (1) is connected with the inlet of the cutting machine (4) through a first valve (3), the outlet of the cutting machine (4) is connected with the inlet of the dehydrator (7) through a second valve (6), and the outlet of the dehydrator (7) is connected with the inlet of the preheater (10) through a third valve (9).
3. The sludge thermochemical treatment system of two-stage pyrolysis assisted by low-temperature carbonization according to claim 2, wherein a first conveying device (2) is arranged on a pipeline connecting the sludge storage bin (1) and the cutting machine (4); a second conveying device (5) is arranged on a pipeline connecting the cutting machine (4) and the dehydrator (7); a third conveying device (8) is arranged on a pipeline connecting the dehydrator (7) and the heat exchanger (14); a fourth conveying device (20) is arranged on a pipeline connecting the pressure reducing device (19) and the grinding machine (21); and a fifth conveying device (22) is arranged on a pipeline connecting the grinding machine (21) and the two-section pyrolysis furnace (25).
4. The sludge thermochemical treatment system of two-stage pyrolysis assisted by low-temperature carbonization according to claim 3, wherein pumps are used for the first conveying device (2), the second conveying device (5) and the third conveying device (8), and screw conveyors are used for the fourth conveying device (20) and the fifth conveying device (22).
5. The sludge thermochemical treatment system of two-stage pyrolysis assisted by low-temperature carbonization according to any of claims 1 to 4, wherein a plurality of tar collection devices (28) are arranged in series, the inlet end of the tar collection device arranged at the head is connected to the outlet end of the gas-solid separator (27), and the outlet end of the tar collection device arranged at the tail is connected to the scrubber (29).
6. The system for thermochemically treating sludge through two-stage pyrolysis assisted by low-temperature carbonization according to any one of claims 1 to 4, wherein the two-stage pyrolysis furnace adopts a tubular reactor or a kettle reactor, and heating equipment adopted in the two-stage pyrolysis furnace is an electromagnetic heater or a resistance heater.
7. The system for thermochemically treating sludge through low-temperature carbonization-assisted two-stage pyrolysis according to any one of claims 1 to 4, wherein the gas-solid separator is a cyclone separator, the scrubber is a Venturi scrubber or a wet scrubber, and the filter is a paper filter or a water filter.
8. The sludge treatment method of the sludge thermochemical treatment system based on the low-temperature carbonization-assisted two-stage pyrolysis according to any one of claims 1 to 7, comprising the steps of:
1) the sludge enters a low-temperature carbonization unit for low-temperature carbonization treatment, and the carbonized sludge is converted into a cracking solution;
2) the pyrolysis liquid flows through the heat exchanger (14) to preheat the dewatered sludge which does not enter the heat exchanger (14), and the pyrolysis liquid after energy recovery and utilization flows into the condenser (16) to be condensed;
3) the condensed sludge lysate flows into a dryer (18) for drying, and the dried mud cake is sent into a grinder (21) for grinding and granulation;
4) feeding the granulated sludge ground in the step 3) into a two-section pyrolysis furnace (25) for pyrolysis, and simultaneously feeding nitrogen in a nitrogen supply device (23) into the two-section pyrolysis furnace (25) for purging and deoxidizing;
5) and (3) separating the pyrolysis product treated in the step (4) by a gas-solid separator (27) to obtain coke, decoking the residual gas-phase product by a tar collecting device (28), washing by a washer (29), filtering by a filter (30) and collecting by a gas collector (32) to obtain clean synthesis gas.
9. The sludge treatment method according to claim 8, further comprising an operation of pretreating the sludge before the step 1), including cutting and dewatering the sludge.
10. The sludge treatment method according to claim 8, wherein in the step 4), the pyrolysis temperature is 500 to 800 ℃.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2824286A1 (en) * | 1978-06-02 | 1979-12-13 | Adolf H Borst | Activated carbon mfr. from organic material - in dryer, carbonising and activation furnace with reactant gas counter flow |
| FR2841233A1 (en) * | 2002-06-24 | 2003-12-26 | Commissariat Energie Atomique | METHOD AND DEVICE FOR PYROLYSIS DEPOSITION OF CARBON NANOTUBES |
| CN101708938A (en) * | 2009-11-06 | 2010-05-19 | 杭鹏志 | Sludge or organic garbage high-low temperature coupling themolysis method |
| CN101871649A (en) * | 2010-07-07 | 2010-10-27 | 广东长青（集团）股份有限公司 | System for pyrolyzing and burning sludge at low temperature |
| CN102433166A (en) * | 2011-10-25 | 2012-05-02 | 陕西华祥能源科技集团有限公司 | Moving bed pulverized coal pyrolysis and fluidized bed coke powder gasification coupled device and coupling method thereof |
| CN104355519A (en) * | 2014-10-29 | 2015-02-18 | 华南理工大学 | Comprehensive sludge treating method based on hydrothermal carbonization and fast microwave pyrolysis |
-
2021
- 2021-03-11 CN CN202110267407.0A patent/CN113003911B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2824286A1 (en) * | 1978-06-02 | 1979-12-13 | Adolf H Borst | Activated carbon mfr. from organic material - in dryer, carbonising and activation furnace with reactant gas counter flow |
| FR2841233A1 (en) * | 2002-06-24 | 2003-12-26 | Commissariat Energie Atomique | METHOD AND DEVICE FOR PYROLYSIS DEPOSITION OF CARBON NANOTUBES |
| CN101708938A (en) * | 2009-11-06 | 2010-05-19 | 杭鹏志 | Sludge or organic garbage high-low temperature coupling themolysis method |
| CN101871649A (en) * | 2010-07-07 | 2010-10-27 | 广东长青（集团）股份有限公司 | System for pyrolyzing and burning sludge at low temperature |
| CN102433166A (en) * | 2011-10-25 | 2012-05-02 | 陕西华祥能源科技集团有限公司 | Moving bed pulverized coal pyrolysis and fluidized bed coke powder gasification coupled device and coupling method thereof |
| CN104355519A (en) * | 2014-10-29 | 2015-02-18 | 华南理工大学 | Comprehensive sludge treating method based on hydrothermal carbonization and fast microwave pyrolysis |
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