Pyrolysis carbonization treatment system for sludge and carbonization treatment method thereof

Abstract

The invention discloses a pyrolysis carbonization treatment system for sludge and a carbonization treatment method thereof. The pyrolysis carbonization treatment system comprises a sludge pretreatment device, a multi-section carbonization furnace and a tail gas treatment device which are communicated in sequence, the sludge pretreatment device comprises a plate-and-frame filter press and a paddle dryer which are connected with each other; a combustion-supporting device for receiving drying tail gas and supporting combustion for the multi-section carbonization furnace is arranged at the top of the paddle dryer; the multi-section carbonization furnace comprises a drying layer, a carbonization layer and an activation layer which are communicated from top to bottom, and a steam injector for injecting steam into the activation layer and a combustor for secondarily heating the activation layer are mounted on the outer wall of the multi-section carbonization furnace; compared with the prior art, the separation between the drying tail gas and the sludge is realized through the paddle dryer, the generated drying tail gas is supplied to the multi-section carbonization furnace for combustion under the action of the combustion-supporting device, and the anoxic combustion in the multi-section carbonization furnace is realized under the action of limited sludge gas, so that the carbonization requirement of the sludge in the multi-section carbonization furnace is met; and the sludge in the multi-section carbonization furnace is pyrolyzed, carbonized and activated.

Description

Technical Field

[0001] The present invention relates to the technical field of sludge treatment, and in particular to a pyrolysis carbonization treatment system for sludge and a carbonization treatment method thereof. Background Art

[0002] In the printing and dyeing industry, there is a large amount of printing and dyeing sludge, which comes from the sediment in the printing and dyeing wastewater treatment process, including fiber residues, chemical reagent sediments and high-concentration organic matter generated by desizing, scouring, dyeing and other processes.

[0003] In the existing technology, direct incineration and drying are usually used to treat printing and dyeing sludge. However, during the incineration process, since the printing and dyeing sludge may contain volatile organic compounds such as dye auxiliaries and benzene series, direct exposure will cause harmful gases to escape and pollute the air. In addition, the printing and dyeing sludge will produce decomposition products such as sulfide and ammonia during the incineration process, which may produce odor and affect the surrounding environment. At the same time, the printing and dyeing sludge contains heavy metals, and dust may spread with the wind during the incineration process, increasing the risk of soil and water pollution.

[0004] Chinese publication number CN214571448U discloses a sludge pyrolysis treatment system based on a multi-stage furnace, including a sludge pyrolysis treatment system and a pyrolysis tail gas treatment system. The sludge pyrolysis treatment system includes a sludge storage tank, a paddle dryer, a feed elevator, a multi-stage pyrolysis furnace, a drum cooler, a discharge elevator and a discharge storage tank for sequentially transporting the sludge; the tail gas treatment system is used to treat the tail gas after sludge pyrolysis, including a secondary combustion furnace, a waste heat boiler, an economizer, a bag dust collector, a precooler, a washing tower, a biological deodorization tower, an induced fan and a chimney connected in sequence from the tail gas discharge port of the multi-stage pyrolysis furnace.

[0005] The sludge pyrolysis treatment system disclosed above simply uses a multi-stage pyrolysis furnace to incinerate and dry the sludge, but does not specify the discharge of the dried material. Since printing and dyeing sludge contains heavy metals, heavy metals are still present in the material after incineration in the multi-stage pyrolysis furnace. Directly burying the material will cause soil and water pollution. Summary of the Invention

[0006] The present invention aims to overcome the above-mentioned defects in the prior art and provide a pyrolysis carbonization treatment system and a carbonization treatment method for sludge which have good treatment effect and can realize resource recycling.

[0007] In order to achieve the above-mentioned purpose of the invention, the present invention adopts the following technical scheme: a pyrolysis carbonization treatment system for sludge, comprising a sludge pretreatment device, a multi-stage carbonization furnace and an exhaust gas treatment device connected in sequence; the top of the sludge pretreatment device is provided with a combustion-supporting device for receiving dried exhaust gas and supplying oxygen to the multi-stage carbonization furnace; the multi-stage carbonization furnace is connected in sequence from top to bottom with a drying layer, a carbonization layer and an activation layer, and a steam injector for injecting steam into the activation layer and a burner for secondary heating of the activation layer are installed on the outer wall of the multi-stage carbonization furnace; the exhaust gas treatment device comprises a secondary furnace, a waste heat boiler, a bag dust collector and a multi-stage washing tower connected in sequence.

[0008] As a preferred solution of the present invention, the sludge pretreatment device includes a plate and frame filter press and a paddle dryer connected to each other, and the combustion-supporting device is connected to the top of the paddle dryer.

[0009] As a preferred solution of the present invention, the multi-stage carbonization furnace has and only has a combustion-supporting device for supplying oxygen.

[0010] As a preferred embodiment of the present invention, the multi-stage carbonization furnace includes a furnace body and a central axis rotatably arranged in the middle of the furnace body, and the furnace body is provided with a plurality of furnace beds arranged in stages from top to bottom, and a rake arm corresponding to the position of the furnace bed is installed on the central axis, and the rake arm is provided with rake teeth for evenly spreading the sludge on the furnace bed.

[0011] As a preferred solution of the present invention, the drying layer, carbonization layer and activation layer are divided according to the hearth height from top to bottom, and the steam injector and burner are arranged at the hearth position corresponding to the activation layer.

[0012] As a preferred solution of the present invention, the hearth is arranged upwardly and tilted from the outside to the inside of the furnace body, and several hearths from top to bottom are provided with alternately arranged discharge ports on both sides thereof, and the rake teeth form a curved structure for moving the sludge toward the discharge port.

[0013] As a preferred solution of the present invention, the waste heat boiler is connected to the paddle dryer and the steam injector.

[0014] As a preferred solution of the present invention, a conveying device for conveying pretreated sludge is provided between the sludge pretreatment device and the multi-stage carbonization furnace.

[0015] A carbonization treatment method for a pyrolysis carbonization treatment system for sludge, based on the pyrolysis carbonization treatment system for sludge according to any one of claims 1 to 8, comprises the following steps: Step A: The sludge to be treated is fed into a plate and frame filter press, and the sludge is dehydrated to a moisture content of less than 60% under the action of the plate and frame filter press to form a filter cake; Step B: The formed filter cake is conveyed to a paddle dryer, where the moisture content of the filter cake is reduced to 25%-35% under the conductive heating effect of the paddle dryer, forming a granular structure. The gas generated by the paddle dryer is purified by the combustion-supporting device and then fed into a multi-stage carbonization furnace; Step C: The granular sludge is transported to the top of the multi-stage carbonization furnace by a pneumatic conveying device. The granular sludge entering the multi-stage carbonization furnace passes through a drying layer, a carbonization layer, and an activation layer in sequence. After entering the carbonization layer, the sludge begins to carbonize in an oxygen-deficient environment. The carbonized sludge undergoes a water-gas reaction under the action of a secondary high temperature and steam, wherein the fully reacted sludge forms activated carbon, and the incompletely reacted sludge forms biochar and sludge charcoal. Step D: The flue gas generated by the multi-stage carbonization furnace enters the tail gas treatment device, is fully burned in the secondary furnace, and the heat generated by the full combustion is recovered by the waste heat boiler; Step E: The tail gas is further purified by the bag filter and multi-stage scrubber until it is discharged.

[0016] As a preferred embodiment of the present invention, the steam generated by the waste heat boiler in step D is supplied to the paddle dryer and the steam injector.

[0017] Compared with the existing technology, the paddle dryer can achieve dehydration and drying of the sludge while separating the sludge gas from the sludge. Under the action of the combustion-supporting device, the generated drying tail gas is supplied to the multi-stage carbonization furnace for combustion. Under the action of limited drying tail gas, oxygen-deficient combustion is achieved in the multi-stage carbonization furnace, meeting the carbonization requirements of the sludge in the multi-stage carbonization furnace, so that the sludge in the multi-stage carbonization furnace is pyrolyzed and carbonized and activated, realizing energy recovery in the sludge. Moreover, under the action of the combustion-supporting device and the tail gas treatment device, the utilization and recovery of multiple stages of different tail gases in the sludge during the pyrolysis and carbonization activation process are realized, and the overall resource utilization is efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a connection diagram of the control handle and the adjustment mechanism; Figure numerals: plate and frame filter press 1, paddle dryer 2, combustion-supporting device 3, multi-stage carbonization furnace 4, furnace body 41, drying layer 42, carbonization layer 43, activation layer 44, central axis 45, furnace bed 46, discharge port 461, rake arm 47, rake teeth 471, burner 48, steam injector 49, secondary furnace 5, waste heat boiler 6, bag dust collector 7, multi-stage washing tower 8, exhaust chimney 9. DETAILED DESCRIPTION

[0019] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0020] like Figure 1-Figure 2 As shown, a pyrolysis carbonization treatment system for sludge includes a sludge pretreatment device, a multi-stage carbonization furnace 4 and an exhaust gas treatment device connected in sequence; the sludge pretreatment device includes a plate and frame filter press 1 and a paddle dryer 2 connected to each other, and a combustion-supporting device is provided on the top of the paddle dryer 2 for receiving dried exhaust gas and providing combustion support to the multi-stage carbonization furnace 4; the multi-stage carbonization furnace 4 is connected in sequence from top to bottom to a drying layer 42, a carbonization layer 43 and an activation layer 44, and a steam injector 49 for injecting steam into the activation layer 44 and a burner 48 for secondary heating the activation layer 44 are installed on the outer wall of the multi-stage carbonization furnace 4; the exhaust gas treatment device includes a secondary furnace 5, a waste heat boiler 6, a bag dust collector 7 and a multi-stage washing tower 8 connected in sequence.

[0021] The water content of sludge is usually as high as 80%-99%. Under the squeezing action of the plate and frame filter press 1, the sludge is partially dehydrated and squeezed into a filter cake structure. A filter cake dragon is provided at the discharge port of the plate and frame filter press 1 for conveying the filter cake to the filter cake silo 11. The paddle dryer 2 is a double-shaft dryer that uses heat conduction as the main means of heat exchange. It relies on the heat from the hot wall of the double-shaft dryer to contact, stir and squeeze the sludge particles for heat exchange. Under the indirect conduction heating effect of the paddle dryer 2, the paddle dryer 2 does not carry away the heat with air. The heat is used to heat the material. The only heat loss is the heat dissipation to the environment through the insulation layer of the device body.

[0022] The rotating shaft of the paddle dryer 2 is densely arranged with wedge-shaped blades. The heat transfer surface of the wedge-shaped blades has a self-cleaning function. The relative movement of the sludge particles and the wedge-shaped surface produces a scrubbing effect, which can wash away the materials attached to the wedge-shaped surface, so that the heat transfer surface is always kept clean during operation. After the sludge is dried by the paddle dryer 2, it is transported to the high-level silo 21 for temporary storage through the wind conveying device 22.

[0023] The combustion-supporting device includes a drying spray tower 31, a plate condenser 32 and a drying fan 33 which are connected in sequence. During the process of drying the sludge by the paddle dryer 2, exhaust gas containing a certain amount of water vapor and sludge dust is generated. The exhaust gas is sucked by the drying fan 3333, wet-sprayed by the drying spray tower 31, cooled and dust-removed, and then cooled and condensed by the plate condenser 32. After most of the water vapor is removed, the exhaust gas enters the combustion system as combustion-supporting air, completely solving the pollution problem of indirect drying exhaust gas.

[0024] The multi-stage carbonization furnace 4 includes a furnace body 41 and a central shaft 45 rotatably arranged in the middle of the furnace body 41, and a plurality of furnace beds 46 arranged in stages from top to bottom are provided in the furnace body 41. A rake arm 47 corresponding to the position of the furnace bed 46 is installed on the central shaft 45, and the rake arm 47 is provided with rake teeth 471 for evenly spreading the sludge on the furnace bed 46.

[0025] A motor for driving the central shaft 45 to rotate is provided at the bottom of the multi-stage carbonization furnace 4. Under the rotation of the central shaft 45, the rake arms 47 and the rake teeth 471 are driven to rotate synchronously, thereby realizing the movement of the rake teeth 471 on the surface of the hearth 46.

[0026] The drying layer 42 , the carbonized layer 43 and the activation layer 44 are divided according to the height of the hearth 46 from top to bottom, and the injector and the burner 48 are arranged at the hearth 46 position corresponding to the activation layer 44 .

[0027] The feed port of the multi-stage carbonization furnace 4 is located at the top of the multi-stage carbonization furnace 4. Under the action of the drying layer 42, carbonization layer 43 and activation layer 44 distributed from top to bottom, the sludge passes through the drying layer 42, carbonization layer 43 and activation layer 44 in sequence under the action of the rake teeth 471.

[0028] After the sludge is fed, it is evenly distributed on the surface of the hearth 46 under the movement of the rake teeth 471 of the rake arm 47. The rake teeth 471 rake the sludge again and again to increase the contact area between the sludge and the hearth 46 to promote heat energy transfer and mass transfer rate.

[0029] The hearth 46 is arranged upwardly and tilted from outside to inside along the furnace body 41 , and alternately arranged discharge ports 461 are formed on the inner and outer sides of the hearths 46 from top to bottom, and the rake teeth 471 form a curved structure for moving the sludge toward the discharge ports 461 .

[0030] Under the action of the alternately arranged discharge ports 461 , the movement path of the sludge during the falling process is extended, thereby ensuring that the sludge is heated in the drying layer 42 , the carbonization layer 43 and the activation layer 44 .

[0031] The drying layer 42, the carbonized layer 43 and the activated layer 44 are all in a state of heating the sludge. Under the action of the burner 48, the temperature at the activated layer 44 is higher than the temperature at the drying layer 42 and the carbonized layer 43. Since the carbonized layer 43 is arranged close to the activated layer 44, the temperature at the drying layer 42, the carbonized layer 43 and the activated layer 44 gradually increases from top to bottom.

[0032] Under the heating effect of drying layer 42, the remaining water in the sludge is separated from the sludge in the form of steam. After drying, the sludge moves downward under the action of rake teeth 471 and enters carbonization layer 43. At this time, the organic matter in the sludge begins to carbonize in the oxygen-deficient environment. The low-volatile substances, hydrogen, and oxygen elements in the organic matter are removed according to the composition ratio of water, leaving black carbon, thus carbonizing it. The carbonized sludge moves downward under the action of 471 and enters activation layer 44. The temperature in activation layer 44 is raised to 800℃~1000℃ by the action of burner 48. At this time, steam is injected into activation layer 44, and the steam reacts with the carbon in the carbonized sludge to form a water-gas reaction: .

[0033] After the carbonization, part of the carbon in the sludge reacts with water vapor to generate carbon monoxide and hydrogen, completing the activation and forming fine pores on the surface to prepare activated carbon. The remaining part is biochar and sludge charcoal, where the biochar is the sludge that has not reacted in the activation layer 44 after carbonization in the carbonization layer 43, and the sludge charcoal is the sludge that has not been carbonized in an oxygen-deficient environment and has not reacted in the activation layer 44.

[0034] Since sludge charcoal is not carbonized in an oxygen-deficient environment, some organic matter and nutrients are retained in it, and it can be used as a soil conditioner. At the same time, sludge charcoal can be used as cement aggregate / additive and then added to cement. The heavy metals in sludge charcoal are solidified in the mineral phase, and there is no risk of secondary release.

[0035] Since the biochar is carbonized in the carbonization layer 43 , a carbonized surface is formed on the surface of the biochar, which can adsorb heavy metals and organic matter in the sludge carbon.

[0036] The activated carbon after regeneration is discharged from the bottom discharge hole of the multi-stage carbonization furnace 4, cooled by the slag cooler, and transported into the finished product silo through the wind conveying system, while the flue gas coming out from the top of the multi-stage carbonization furnace 4 is sent to the exhaust gas treatment device for heat recovery and pollutant treatment.

[0037] The secondary furnace 5 is connected to the top of the multi-stage carbonization furnace 4. Sufficient air and auxiliary fuel are introduced into the secondary furnace 5 to heat the flue gas to above 850°C and keep it there for 2 seconds, so that the volatile matter and pyrolysis gas in the flue gas are completely converted into harmless CO2 and H2O and harmful substances such as dioxins are destroyed.

[0038] A waste heat boiler 6 is provided at the outlet of the secondary furnace 5. The waste heat boiler 6 is a vertical structure, and adopts a membrane wall, a convection section, and a coal economizer structure. The heat of the flue gas at the outlet of the secondary combustion chamber is used to produce steam as a by-product. The waste heat boiler 6 is connected to the blade dryer 2 and the steam injector 49. Part of the steam is used for activation of the blade dryer 2 and the multi-stage carbonization furnace 4, and the surplus steam can be supplied externally.

[0039] The flue gas temperature after waste heat utilization by the waste heat boiler 6 is reduced to below 200° C., and the cooled flue gas then enters the bag filter 7 to remove particulate materials.

[0040] The bag dust collector 7 adopts a new circular structure. The main part of the filtering system of the bag dust collector 7 adopts a circular design, tangential air inlet, and no dead angle. The bag dust collector 7 includes a flue gas conveying pipeline, a pulse backflushing process, a filtering dust removal system, a residue collection system, etc.

[0041] The key to the bag dust collector 7 lies in the rational design of the electrical control system. The pulse jet tube performs pulse back-blow filtering in random sequence to achieve a dust removal effect of dust ≤ 10mg / Nm3. At the same time, during the operation of the bag dust collector 7 and under normal load, the maximum pressure difference of the back-blow process will be maintained below 1.2kpa, and the operation is reliable. The filter bag back-blow cleaning performance is excellent. The bottom of the dust collector is flat and adopts a rotating scraper system to force dust discharge, clean the dust at the bottom in real time, and avoid dust accumulation.

[0042] The multi-stage washing tower 8 includes a cooling alkali washing spray tower, an alkali washing spray tower and a water washing spray tower which are connected in sequence. After the flue gas is dusted by the bag dust collector 7, it enters the three-stage washing tower for desulfurization. The flue gas first enters the cooling alkali washing spray tower. The flue gas is introduced from the lower part of the cooling alkali washing spray tower. During the rising process of the flue gas, it contacts the sprayed alkaline solution. The acidic gas in the flue gas is neutralized by the alkaline solution. After passing through the cooling alkali washing spray tower, the flue gas enters the alkali washing spray tower to further absorb the acidic gas in the flue gas. After that, the flue gas enters the water washing spray tower. Clean water is sprayed in the water washing spray tower to clean the exhaust gas and wash away the alkali solution and salt particles entrained in the flue gas. At the same time, the flue gas temperature is further reduced. The pollutants in the flue gas are removed by the multi-stage washing tower to meet the emission standards.

[0043] A carbonization treatment method for a pyrolysis carbonization treatment system for sludge, based on the pyrolysis carbonization treatment system for sludge, comprises the following steps: Step A: The sludge to be treated is fed into the plate and frame filter press 1 , and the sludge is dehydrated to a moisture content of less than 60% under the action of the plate and frame filter press 1 to form a filter cake.

[0044] Step B: The formed filter cake is transported to the paddle dryer 2, and the moisture content of the filter cake is reduced to 25%-35% under the conductive heating action of the paddle dryer 2 to form a granular structure. The gas generated by the paddle dryer 2 is purified under the action of the combustion-supporting device and then input into the multi-stage carbonization furnace 4. The gas serves as the combustion-supporting air of the multi-stage carbonization furnace 4. At the same time, the amount of the gas is effective to ensure that when the sludge is in the carbonization layer 43, the organic matter in the sludge begins to carbonize in an oxygen-deficient environment, and the low-volatile substances and hydrogen and oxygen elements in the organic matter are removed according to the composition ratio of water, leaving black carbon, thereby carbonizing it.

[0045] After passing through the paddle dryer 2, the sludge is dried and the solid and gas of the sludge are separated, thereby realizing the secondary utilization of the gas without causing sludge overflow.

[0046] Step C: The granular sludge is transported to the top of the multi-stage carbonization furnace 4 by the wind conveying device 22. The granular sludge entering the multi-stage carbonization furnace 4 passes through the drying layer 42, the carbonization layer 43 and the activation layer 44 in sequence. After entering the carbonization layer 43, the sludge begins to carbonize in an oxygen-deficient environment, and the carbonized sludge undergoes a water-gas reaction under the action of secondary high temperature and steam, wherein the fully reacted sludge forms activated carbon, and the incompletely reacted sludge forms biochar and sludge charcoal.

[0047] Step D: The flue gas generated by the multi-stage carbonization furnace 4 enters the tail gas treatment device and is fully burned in the secondary furnace 5. The heat generated by the full combustion is recovered by the waste heat boiler 6. The steam generated by the waste heat boiler 6 is supplied to the paddle dryer 2 and the steam injector 49.

[0048] Step E: The tail gas is further purified by the bag filter 7, the multi-stage scrubber and the demister until it is discharged.

[0049] The above description of the disclosed embodiments will enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein, but is to be embodied in the widest possible manner consistent with the principles and novel features disclosed herein.

[0050] Although this document frequently uses the following terms in the figures: plate and frame filter press 1, paddle dryer 2, combustion-supporting device 3, multi-stage carbonization furnace 4, furnace body 41, drying layer 42, carbonization layer 43, activation layer 44, central axis 45, hearth 46, feed port 461, rake arm 47, rake teeth 471, burner 48, steam injector 49, secondary furnace 5, waste heat boiler 6, bag filter 7, multi-stage scrubber 8, exhaust chimney 9, etc., the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional limitations is contrary to the spirit of the present invention.

Claims

1. A pyrolysis carbonization treatment system for sludge, comprising a sludge pretreatment device, a multi-stage carbonization furnace (4) and an exhaust gas treatment device connected in sequence; characterized in that, The top of the sludge pretreatment device is provided with a combustion-supporting device (3) for receiving dried tail gas and supplying oxygen to the multi-stage carbonization furnace (4); the multi-stage carbonization furnace (4) is connected to a drying layer (42), a carbonization layer (43) and an activation layer (44) in sequence from top to bottom, and a steam injector (49) for injecting steam into the activation layer (44) and a burner (48) for secondary heating the activation layer (44) are installed on the outer wall of the multi-stage carbonization furnace (4); the tail gas treatment device includes a secondary furnace (5), a waste heat boiler (6), a bag dust collector (7) and a multi-stage washing tower (8) connected in sequence.

2. A pyrolysis carbonization treatment system for sludge according to claim 1, characterized in that: The sludge pretreatment device comprises a plate and frame filter press (1) and a paddle dryer (2) connected to each other, and a combustion-supporting device (3) is connected to the top of the paddle dryer (2).

3. The pyrolysis carbonization treatment system for sludge according to claim 1, characterized in that: The multi-stage carbonization furnace (4) has and only has a combustion-supporting device (3) for supplying oxygen.

4. The pyrolysis carbonization treatment system for sludge according to claim 1, characterized in that: The multi-stage carbonization furnace (4) includes a furnace body (41) and a central shaft (45) rotatably arranged in the middle of the furnace body (41), and a plurality of furnace beds (46) arranged in a graded manner from top to bottom are provided in the furnace body (41), a rake arm (47) corresponding to the position of the furnace bed (46) is installed on the central shaft (45), and rake teeth (471) are provided on the rake arm (47) for evenly spreading the sludge on the furnace bed (46).

5. A pyrolysis carbonization treatment system for sludge according to claim 4, characterized in that: The drying layer (42), the carbonization layer (43) and the activation layer (44) are divided according to the height of the hearth (46) from top to bottom, and the steam injector (49) and the burner (48) are arranged at the position of the hearth (46) corresponding to the activation layer (44).

6. The pyrolysis carbonization treatment system for sludge according to claim 4, characterized in that: The hearth (46) is arranged upwardly and tilted from outside to inside along the furnace body (41), and alternately arranged discharge openings (461) are formed on the inner and outer sides of the plurality of hearths (46) from top to bottom, and the rake teeth (471) are formed with a curved structure for moving the sludge toward the discharge opening (461).

7. The pyrolysis carbonization treatment system for sludge according to claim 1, characterized in that: The waste heat boiler (6) is connected to the blade dryer (2) and the steam injector (49).

8. The pyrolysis carbonization treatment system for sludge according to claim 1, characterized in that: A conveying device for conveying pretreated sludge is provided between the sludge pretreatment device and the multi-stage carbonization furnace (4).

9. A carbonization treatment method for a pyrolysis carbonization treatment system for sludge, characterized in that: The pyrolysis carbonization treatment system for sludge according to any one of claims 1 to 8 comprises the following steps: Step A: The sludge to be treated is fed into a plate and frame filter press (1), and the sludge is dehydrated to a moisture content of less than 60% under the action of the plate and frame filter press (1), thereby forming a filter cake; Step B: conveying the formed filter cake to a paddle dryer (2), reducing the water content of the filter cake to 25%-35% under the conductive heating action of the paddle dryer (2), forming a granular structure, and purifying the gas generated by the paddle dryer (2) under the action of a combustion-supporting device (3) and then conveying it to a multi-stage carbonization furnace (4); Step C: The granular sludge is transported to the top of the multi-stage carbonization furnace (4) by the wind conveying device (22). The granular sludge entering the multi-stage carbonization furnace (4) passes through the drying layer (42), the carbonization layer (43) and the activation layer (44) in sequence. After entering the carbonization layer (43), the sludge begins to be carbonized in an oxygen-deficient environment, and the carbonized sludge undergoes a water-gas reaction under the action of secondary high temperature and steam, wherein the fully reacted sludge forms activated carbon, and the incompletely reacted sludge forms biochar and sludge charcoal. Step D: The flue gas generated by the multi-stage carbonization furnace (4) enters the tail gas treatment device, is fully burned in the secondary furnace (5), and the heat generated by the full combustion is recovered by the waste heat boiler (6); Step E: The tail gas is further purified by the bag filter (7) and the multi-stage scrubber (8) until it is discharged.

10. The carbonization treatment method for sludge according to claim 1, characterized in that: The steam generated by the waste heat boiler (6) in step D is supplied to the paddle dryer (2) and the steam injector (49).

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