CN220550097U

CN220550097U - Municipal sludge drying and cement production line coupling system

Info

Publication number: CN220550097U
Application number: CN202321008876.1U
Authority: CN
Inventors: 宿向超; 赵美江; 孙德群; 姜凯; 谷沁洋; 黄锋; 潘轶; 陈翼; 陈蕾; 朱永长; 汤升亮; 宁建根
Original assignee: Sinoma International Engineering Co ltd
Current assignee: Sinoma International Engineering Co ltd
Priority date: 2023-04-28
Filing date: 2023-04-28
Publication date: 2024-03-01
Anticipated expiration: 2033-04-28

Abstract

The utility model discloses a municipal sludge drying and cement production line coupling system which comprises an indirect drying system, a belt drying system, a waste gas treatment system, a precombustion system and a cooperative treatment system. The steam of the waste heat boiler enters an indirect drying system to indirectly heat wet sludge to obtain semi-dry sludge; granulating the semi-dried sludge to obtain granulated sludge, and sending the granulated sludge into a belt type drying system to contact with hot air of a kiln head for further drying to obtain dry sludge; the steam is subjected to heat exchange with wet sludge to generate condensation water, the condensation water is sent to a belt type drying system, and the condensation water is subjected to heat exchange with kiln head hot air to cool and then enters a deaerator; condensing and dewatering the drying gas, and then sending the drying gas into a high-temperature section of the grate cooler; the environmental waste gas is sent to a high temperature section of the grate cooler or is discharged after deodorization; the dry sludge is sent into a precombustion system to be pre-burnt in contact with high-temperature air of a grate cooler, and the generated high-temperature flue gas and ash are sent into a decomposing furnace. The utility model fully utilizes various waste heat sources of the cement production line to dry the sludge to the greatest extent, improves the heat value of the sludge and avoids environmental pollution.

Description

Municipal sludge drying and cement production line coupling system

Technical Field

The utility model relates to a system for cooperatively disposing solid waste in a cement production line, in particular to a system for coupling municipal sludge drying with the cement production line.

Background

For municipal sludge, the current common treatment methods include sanitary landfill, incineration, composting, agriculture and the like. Because the sludge contains a plurality of harmful substances, pollutants such as dioxin and the like can be generated after simple incineration, secondary pollution is caused, and the cement production system is utilized to cooperatively treat the municipal sludge, so that the method has the advantages of cleanness, safety, sustainability and the like. Meanwhile, the municipal sludge contains combustible substances, has a certain heat value (the sludge containing 50% of water generally and having low-temperature heat productivity of 1500-2000 kcal/kg), can be used as a substitute fuel for a cement production system, and the main chemical components of ash after sludge incineration are similar to the main components of cement, so that the sludge can be used as a cement production raw material. Thus, co-disposal with cement lines is one of the ideal disposal modes for municipal sludge.

However, municipal sludge has a large general water content, generally 60% -80%, and is directly sent to a decomposing furnace of a cement production line for treatment, so that the safe operation of a cement kiln and energy conservation and consumption reduction are negatively affected, the stability of a cement sintering system is affected, and the sludge treatment amount is difficult to improve. At present, the sludge treatment amount is improved, the negative influence of the high water content of the sludge is reduced, and the main technical means is that wet sludge is subjected to a pre-drying process, and the dried sludge is directly sent into a decomposing furnace or sent into the decomposing furnace for treatment after passing through a pre-burning furnace. However, a large amount of energy is consumed for drying the wet sludge, the higher the sludge drying degree is, the larger the energy consumption is, and meanwhile, the lower the water content of the sludge is, the higher the heat value is, so that the treatment of a cement production line is facilitated.

Patent CN201410792166.1 discloses a method for disposing sludge by a cement kiln and a sludge gasification cement kiln system, and the utility model can greatly improve the disposal scale of sludge; the difference between the form of the solid sludge directly fed into the kiln and the fineness of the pulverized coal and cement raw materials is reduced, and the mass and heat transfer effect is improved. However, the scheme has limited sludge precipitation, a treatment scheme of a heat source and drying waste gas of the sludge indirect drying machine is not provided, the whole sludge drying process does not utilize the system characteristics of a cement kiln, and a heat source and a deodorizing system are additionally added, so that the system investment and the operation cost are increased.

Disclosure of Invention

The utility model aims to: the utility model aims to provide a municipal sludge drying and cement production line coupling system which fully utilizes various waste heat sources in the cement production line to carry out maximum drying on sludge, improves the heat value of the sludge and simultaneously avoids environmental pollution.

The technical scheme is as follows: the system comprises an indirect drying system for indirectly drying sludge by utilizing steam, a belt type drying system, a waste gas treatment system, a precombustion system and a cooperative treatment system, wherein the system is used for coupling municipal sludge drying and cement production lines; the co-treatment system comprises a waste heat boiler, a deaerator, a grate cooler, a tertiary air pipe and a decomposing furnace on the cement production line; the steam of the waste heat boiler enters an indirect drying system to indirectly heat wet sludge to obtain semi-dry sludge; granulating the semi-dried sludge to obtain granulated sludge, and sending the granulated sludge into a belt type drying system to be directly contacted with kiln head hot air entering the belt type drying system for further drying; the steam is subjected to heat exchange with wet sludge to generate condensation water, the condensation water is sent into a belt type drying system, the condensation water is subjected to heat exchange with kiln head hot air heated by the granulated sludge and then enters a deaerator, the kiln head hot air is heated and then dried to obtain dry sludge, and the kiln head hot air is sent into a high-temperature section of a grate cooler through an exhaust fan; condensing and dewatering drying gas generated in the sludge drying process, and then conveying the drying gas into a high-temperature section of the grate cooler; the generated environmental waste gas is sent to a high temperature section of the grate cooler or is discharged after deodorization; the dry sludge is sent into a precombustion system, and is in contact with the high-temperature air of the grate cooler led out by a tertiary air pipe in the precombustion system to perform precombustion, and the high-temperature flue gas and ash slag generated after the precombustion are sent into a decomposing furnace.

The belt type drying system comprises a belt type dryer, a circulating fan and an exhaust fan; hot flue gas from the kiln head enters a belt dryer to dry granulated sludge on a conveyor belt, and after being pumped out by a circulating fan, the hot flue gas is sent into the belt dryer again to be dried, and then is discharged by an exhaust fan and sent into a grate cooler to be treated.

Further, the belt drying system further comprises a condensation water heat exchanger; hot flue gas from a kiln head enters a belt dryer from the upper part of the front section of the belt dryer, the granulated sludge on a conveyor belt is dried, the granulated sludge is pumped out by a circulating fan and then is sent to the rear section of the belt dryer, the granulated sludge is dried again after heat exchange and temperature rise are carried out on a condensation water heat exchanger and condensation water from an indirect drying system, and the granulated sludge is discharged from the lower part of the rear section of the belt dryer by an exhaust fan and is sent to a grate cooler for treatment; and sending the condensed water after heat exchange to a waste heat boiler. The belt drying system further includes a dry sludge bin for storing dry sludge.

The indirect drying system comprises a wet sludge bin, a sludge indirect dryer, a sludge granulator, a condensate tank for storing condensate water and a drying gas condenser for condensing and removing water from drying gas. The indirect drying system further comprises a sludge conveying and pretreatment system for crushing and pretreating the massive sludge. The wet sludge bin is arranged in a sludge storage workshop, and the sludge conveying and pre-treating system, the sludge indirect drying machine, the sludge granulator, the drying gas condenser and the condensing water tank are all arranged in the sludge drying workshop.

The waste gas treatment system comprises a waste gas exhaust fan for exhausting environmental waste gas, a first air quantity regulating valve for controlling the waste gas to enter a high-temperature section of the grate cooler, an emergency deodorizing system connected with the waste gas exhaust fan, and a second air quantity regulating valve for controlling the waste gas to enter the emergency deodorizing system. The environmental waste gas is generated in the sludge storage and disposal process.

The pre-burning system comprises a pre-burning furnace connected with the belt type drying system and used for pre-burning dry sludge, a branch pipe connected with the pre-burning furnace is arranged on the tertiary air pipe, and a fifth air quantity regulating valve used for regulating the air quantity entering the pre-burning furnace is arranged on the branch pipe. The precombustion system also includes a dosing machine coupled to the precombustion furnace.

The deaerator is respectively connected with the condensed water heat exchanger and the waste heat boiler; the tertiary air pipe is arranged between the high-temperature section of the grate cooler and the decomposing furnace; the kiln head exhaust fan guides out hot air in the grate cooler, and then sends the hot air into the belt dryer through the third air quantity adjusting valve, and redundant exhaust is adjusted by the fourth air quantity adjusting valve and is discharged into a chimney.

The method for coupling municipal sludge drying and cement production lines by using the system comprises the following steps:

(A) The wet sludge is indirectly dried by utilizing steam sent by a waste heat boiler in an indirect drying system to obtain semi-dry sludge, and the semi-dry sludge is granulated by the indirect drying system to obtain granulated sludge; the steam and wet sludge are subjected to heat exchange and temperature reduction to generate condensed water, and then the condensed water is sent to a belt type drying system, and drying gas generated in the sludge drying process is sent to a high-temperature section of a grate cooler for treatment after being condensed and dehydrated; the generated environmental waste gas is sent into a high temperature section of the grate cooler through a waste gas treatment system or is discharged after deodorization;

(B) The granulated sludge is sent into a belt type drying system and is further dried by being in direct contact with kiln head hot air entering the belt type drying system, the condensed water in the step (A) and the kiln head hot air after heating the granulated sludge are sent into a deaerator after heat exchange and cooling, the kiln head hot air is heated and then dried to obtain dry sludge, and then the kiln head hot air is sent into a high temperature section of a grate cooler through an exhaust fan;

(C) When the grate cooler stops running, the environmental waste gas enters a waste gas treatment system for deodorization and then is discharged; when the grate cooler (502) operates, the environmental waste gas enters a high-temperature section of the grate cooler for treatment;

(D) And (C) sending the dry sludge obtained in the step (B) into a precombustion system, pre-burning the dry sludge in contact with high-temperature air of a grate cooler led out by a tertiary air pipe (508) in the precombustion system, and sending high-temperature flue gas and ash slag generated after the pre-burning into a decomposing furnace.

In the step (A), in an indirect drying system, a sludge transport vehicle discharges wet sludge with high water content into a sludge bin, and the wet sludge in the sludge bin is sent to a sludge indirect drying machine after being pretreated by a sludge conveying and pretreatment system. The sludge with the water content of about 80% and better fluidity is sent into the sludge indirect drying machine in a sludge pumping mode, and the blocky wet sludge with the water content of about 60% is sent into the sludge indirect drying machine in a pretreatment device of chain plate machine conveying and crushing by a crusher. The method comprises the steps that a sludge indirect drying machine utilizes steam generated by a cement production line to indirectly dry wet sludge, the moisture content of the wet sludge is reduced to about 40%, the sludge with the moisture content of 40% is sent to a sludge granulator for granulation through a first sludge conveyor, steam in the sludge indirect drying machine exchanges heat with the sludge, the temperature is reduced, water is condensed into water, the water enters a condensation tank, the condensation water is sent to a belt type drying system through a condensation pump, drying gas generated by the sludge indirect drying machine is condensed into water through a condenser and then is sent to a high-temperature section of a grate cooler for treatment through a drying gas exhaust fan, and condensed water generated by the condenser is subjected to sewage treatment;

in the step (B), in a belt type drying system, the granulated sludge from the sludge granulator is heated and dried by hot flue gas with the temperature of 80-120 ℃ from a kiln head on a conveyor belt of the belt type dryer, and is further dried until the water content is less than or equal to 10%, and then is sent into a dry sludge bin; hot flue gas from a kiln head enters a belt dryer from the upper part of the front section of the belt dryer, the granulated sludge on a conveyor belt is dried, the granulated sludge is pumped out by a circulating fan and then sent to the rear section of the dryer, the granulated sludge is dried again after being heated by a condensation water heat exchanger, and the granulated sludge is discharged from the lower part of the rear section by an exhaust fan and sent to a grate cooler in a cement production line for treatment; cooling the condensed water by a condensed water heat exchanger, then sending the cooled condensed water into a deaerator, and sending water in the deaerator into a waste heat boiler of a cement production line;

in the step (C), in the waste gas treatment system, waste gas of a sludge storage workshop and a sludge drying workshop is pumped out through a waste gas exhaust fan and is sent to a high-temperature section of a grate cooler through a first air quantity regulating valve for treatment, when the grate cooler stops running, the waste gas is sent to an emergency deodorizing system in the waste gas treatment system through a second air quantity regulating valve for treatment, and the waste gas is discharged after reaching standards;

in the step (D), in the precombustion system, the second sludge conveyor conveys the sludge in the dry sludge bin to the quantitative feeder for metering, and then the sludge is sent to the precombustion furnace for precombustion and incineration, and the generated flue gas and ash are sent to the decomposing furnace for disposal.

The beneficial effects are that: compared with the prior art, the utility model has the following remarkable effects: (1) The municipal sludge is subjected to two-stage drying by utilizing steam and kiln head hot air generated by a cement production line, so that the waste heat of a cement kiln is utilized, meanwhile, the municipal sludge is subjected to precipitation drying, the water content of the dried sludge is less than or equal to 10%, the heat value of the sludge is greatly improved, and the dried sludge can be used as a substitute fuel to be cooperatively treated in the cement kiln. (2) The indirect sludge drier is adopted as a one-stage sludge drying process, the indirect sludge drier is used for drying the sludge to 40%, steam is used for indirectly heating, the steam is not contacted with the sludge, the produced condensed water can be recycled, and meanwhile, the produced waste gas amount is small, the water vapor amount is large, and the condensation, collection and disposal are convenient; for 80% of sludge to be dried to 10%, 86% of water can be removed in the section; after 40% of the sludge is granulated by a sludge granulator, the surface area is increased, and the subsequent further drying is facilitated. Meanwhile, the high-temperature steam can also play a role in sterilizing the sludge at high temperature, thereby being beneficial to sanitation and safety of the operation environment. (3) The belt dryer is adopted as a two-stage drying process, so that the sludge can be further dried to 10%. The sludge from the first section has high temperature, and after being treated by the granulator, the surface area is increased, so that the drying operation of the belt dryer is facilitated, meanwhile, the circulating hot air is adopted by the belt dryer, the heat of condensed water with the temperature of more than or equal to 100 ℃ of the first section can be utilized, and the heat utilization rate of the steam waste heat is improved. (4) Compared with the indirect sludge drying machine, the method adopts two-stage drying, thereby not only realizing the utilization of kiln head waste gas, but also having the advantage of low water content after sludge drying; compared with a belt dryer, the utility model has the advantages of small overall occupation area of equipment, good sludge drying effect, small system air quantity, small waste gas quantity and low energy consumption by utilizing steam in a cascade mode. The whole effect of 1+1 > 2 is realized.

Drawings

Fig. 1 is a schematic diagram of a system structure according to the present utility model.

Detailed Description

The utility model is described in further detail below with reference to the drawings.

As shown in fig. 1, the utility model provides a municipal sludge drying and cement production line coupling system, which comprises an indirect drying system, a belt drying system, an exhaust gas treatment system, a precombustion system and a co-treatment system.

The indirect drying system comprises a wet sludge bin 101 arranged in a sludge storage workshop, a sludge conveying and pre-treating system 102 arranged in the sludge drying workshop, a sludge indirect drying machine 103, a first sludge conveyor 104, a sludge granulator 105, a condensate tank 106, a condensate pump 107, a drying gas condenser 108 and a drying gas exhaust fan 109. In the indirect drying system, wet sludge in a wet sludge bin 101 is pretreated by a conveying and pretreatment function of a sludge conveying and pretreatment system 102 and then is conveyed to a sludge indirect drying machine 103, the sludge indirect drying machine 103 utilizes steam generated by a cement production line to indirectly dry the wet sludge, the dried sludge is conveyed to a sludge granulator 105 through a first sludge conveyor 104 to be subjected to granulation treatment, the granulated sludge is conveyed to a belt drying system to be further dried, the steam is cooled and condensed into water and then enters a condensate tank 106, a condensate pump 107 conveys the condensed water into a condensate heat exchanger 204 arranged in the belt drying system, and drying gas generated by the sludge indirect drying machine 103 is condensed and dehydrated through a condenser 108 and then is conveyed to a high-temperature section of a grate cooler 502 through a drying gas exhaust fan 109 to be treated.

The sludge indirect drying machine 103 can be a disc sludge indirect drying machine or an indirect drying type drying machine such as a thin-layer sludge indirect drying machine; the sludge conveying and pre-disposing system 102 adopts different equipment and processes according to the physical state of wet sludge, the sludge with better fluidity and water content of about 80% is sent into the sludge indirect drying machine in a sludge pumping mode, the blocky wet sludge with water content of about 60% is conveyed by a chain plate machine, the pre-disposing equipment is crushed by a crusher, and the pretreated sludge is sent into the sludge indirect drying machine 103.

The belt type drying system is also arranged in a sludge drying workshop and specifically comprises a belt type dryer 201, a circulating fan 202, an exhaust fan 203, a condensed water heat exchanger 204 and a dry sludge bin 205; wherein the exhaust fan 203 and the dry sludge bin 205 are placed outside the sludge drying plant. The granulated sludge from the sludge granulator 105 is heated and dried on a conveyor belt of a belt dryer 201 by hot flue gas discharged from a kiln head exhaust fan 503 of a cement production line, and is further dried and then sent into a dry sludge bin 205; hot flue gas from a kiln head enters the belt dryer 201 from the upper part of the front section of the belt dryer 201, the granulated sludge on the conveying belt is dried, the granulated sludge is pumped out by the circulating fan 202 and then sent to the rear section of the belt dryer 201, the sludge is dried again after being heated by the condensation water heat exchanger 204, and the sludge is discharged from the lower part of the rear section by the exhaust fan 203 and is sent to the grate cooler 502 in the cement production line for treatment; the condensed water after heat exchange is sent to the deaerator 507.

The waste gas treatment system comprises a waste gas exhaust fan 301, a first air quantity regulating valve 302, a second air quantity regulating valve 303, an emergency deodorizing system 304 and connecting pipelines. The environmental waste gas of the sludge storage workshop and the sludge drying workshop is pumped out through the waste gas exhaust fan 301 and is sent to the high-temperature section of the grate cooler 502 through the first air quantity regulating valve 302, and when the grate cooler 502 stops running, the environmental waste gas is sent to the emergency deodorizing system 304 through the second air quantity regulating valve 303 for treatment, and is discharged after reaching standards.

The precombustion system of the present utility model comprises a second sludge conveyor 401, a dosing machine 402 and a precombustor 403. The tertiary air pipe is provided with a branch pipe 405 connected with the precombustion furnace 403, and the branch pipe 405 is provided with a fifth air quantity regulating valve 404 for regulating the air quantity entering the precombustion furnace 403. The second sludge conveyor 401 conveys the dry sludge in the dry sludge bin to the quantitative feeder 402 for metering and then sends the dry sludge into the precombustor 403; the high temperature air of the grate cooler enters the precombustion furnace through the branch pipe 405 on the tertiary air pipe to precombuste the dry sludge, and the generated flue gas and ash slag are sent to the decomposing furnace 501 for disposal. When the ash is produced in a large amount, the ash can be sent to a cement raw material batching system or other comprehensive utilization systems.

The co-disposal system includes a waste heat boiler (not shown in the figure), a decomposing furnace 501, a grate cooler 502, a kiln head exhaust fan 503, a third air volume adjusting valve 504, a fourth air volume adjusting valve 505, a chimney 506, and a deaerator 507. The deaerator is respectively connected with the condensed water heat exchanger and the waste heat boiler. A tertiary air pipe 508 is arranged between the high temperature section of the grate cooler 502 and the decomposing furnace 501; the kiln head exhaust fan 503 draws out the hot air in the grate cooler 502, and sends the hot air into the belt dryer 201 through the third air quantity adjusting valve 504, and the redundant exhaust air is adjusted by the fourth air quantity adjusting valve 505 and is discharged into the chimney 506.

(S1) in the indirect drying system, the sludge carrier discharges wet sludge with high water content into the sludge bin 101, and the wet sludge in the sludge bin 101 is pretreated by the sludge conveying and pretreatment system 102 and then is sent to the sludge indirect drying machine 103. The sludge with the water content of about 80% and better fluidity is sent into the sludge indirect drying machine 103 by adopting a sludge pumping mode, and the blocky wet sludge with the water content of about 60% is sent into the sludge indirect drying machine 103 by adopting a pretreatment device of chain plate machine conveying and crushing by a crusher. The sludge indirect drying machine 103 utilizes steam generated by a cement production line to indirectly dry wet sludge, the moisture content of the wet sludge is reduced to about 40%, the sludge with the moisture content of 40% is sent to the sludge granulator 105 for granulation by the first sludge conveyor 104, the steam in the sludge indirect drying machine 103 exchanges heat with the sludge, the temperature is reduced, and the condensed water enters the condensate tank 106, the condensate pump 107 sends the condensed water to the belt type drying machine 201, the drying gas generated by the sludge indirect drying machine 103 is condensed by the condenser 108 to remove water, and then is sent to the high-temperature section of the grate cooler 502 for treatment by the drying gas exhaust fan 109, and the condensed water generated by the condenser 108 removes sewage;

(S2) in a belt type drying system, the granulated sludge from the sludge granulator 105 is heated and dried by hot flue gas with the temperature of 80-120 ℃ from a kiln head on a conveyor belt of the belt type dryer 201, and is further dried until the water content is less than or equal to 10%, and then is sent into a dry sludge bin 205; hot flue gas from a kiln head enters the belt dryer 201 from the upper part of the front section of the belt dryer 201, the granulated sludge on the conveying belt is dried, the granulated sludge is pumped out by the circulating fan 202 and then sent to the rear section of the belt dryer 201, the sludge is dried again after being heated by the condensation water heat exchanger 204, and the sludge is discharged from the lower part of the rear section by the exhaust fan 203 and is sent to the grate cooler 502 in the cement production line for treatment; cooling the condensed water by a condensed water heat exchanger 204, then sending the cooled condensed water into a deaerator 507, and sending water in the deaerator 507 into a waste heat boiler of a cement production line;

(S3) in the waste gas treatment system, waste gas of a sludge storage workshop and a sludge drying workshop is pumped out through a waste gas exhaust fan 301 and is sent to a high-temperature section of a grate cooler 502 for treatment through a first air quantity regulating valve 302, and when the grate cooler 502 stops running, the waste gas is sent to an emergency deodorizing system 304 for treatment through a second air quantity regulating valve 303, and is discharged after reaching standards;

(S4) in the precombustion system, the second sludge conveyor 401 conveys the sludge in the dry sludge bin 205 to the quantitative feeder 402 for metering, and then sends the sludge into the precombustion furnace 403 for precombustion and incineration, and the fifth air quantity regulating valve 404 regulates the air quantity of the grate cooler 502 high Wen Duanfeng entering the precombustion furnace 403; the generated flue gas and ash are sent to a decomposing furnace 501 for disposal. When the ash is produced in a large amount, the ash is sent to a cement raw material batching system or other comprehensive utilization systems.

Claims

1. The system is characterized by comprising an indirect drying system for indirectly drying sludge by utilizing steam, a belt drying system, an exhaust gas treatment system, a precombustion system and a cooperative treatment system; the co-treatment system comprises a waste heat boiler, a deaerator (507), a grate cooler (502), a tertiary air pipe (508) and a decomposing furnace (501) on the cement production line;

the indirect drying system comprises a wet sludge bin (101) arranged in a sludge storage workshop, a sludge conveying and pre-treating system (102) arranged in the sludge drying workshop, a sludge indirect dryer (103), a first sludge conveyor (104), a sludge granulator (105), a condensate tank (106), a condensate pump (107), a drying gas condenser (108) and a drying gas exhaust fan (109); the waste heat boiler is connected with the sludge storage workshop and used for indirectly heating wet sludge in the wet sludge bin (101) by steam of the waste heat boiler to obtain semi-dry sludge; the outlet of the wet sludge bin (101) is connected with the inlet of the sludge conveying and pre-treating system (102), the outlet of the sludge conveying and pre-treating system (102) is connected with the sludge indirect drying machine (103), and the outlet of the sludge indirect drying machine (103) is respectively connected with the drying gas condenser (108), the condensation water tank (106) and the first sludge conveyor (104); the drying gas condenser (108) is used for condensing and dewatering the drying gas generated by the sludge indirect dryer (103), and the drying gas exhaust fan (109) is used for exhausting the drying gas after condensing and dewatering; the condensate water tank (106) is used for storing condensate water generated after heat exchange of wet sludge and steam; the outlet of the first sludge conveyor (104) is connected with a sludge granulator (105) and is used for granulating the semi-dried sludge dried by the sludge indirect dryer to obtain granulated sludge; an outlet of the condensate tank (106) is connected with a condensate pump (107);

the co-treatment system comprises a waste heat boiler, a decomposing furnace (501), a grate cooler (502), a kiln head exhaust fan (503) and a deaerator (507); the deaerator (507) is connected with a waste heat boiler; a tertiary air pipe (508) is arranged between the high temperature section of the grate cooler (502) and the decomposing furnace (501); the kiln head of the grate cooler (502) is connected with a kiln head exhaust fan (503); an air outlet of the drying air exhaust fan (109) is connected with a high-temperature section of the grate cooler (502);

the belt type drying system comprises a belt type dryer (201), a circulating fan (202), an exhaust fan (203), a condensed water heat exchanger (204) and a dry sludge bin (205); the outlet of the sludge granulator (105) is connected with an inlet positioned at the front end of the belt dryer (201), and the outlet of the kiln head exhaust fan (503) is connected with the upper part of the front section of the belt dryer (201) and is used for enabling kiln head hot air to be sent into the belt dryer (201) from the front section of the belt dryer (201) to directly contact granulated sludge entering the belt dryer (201) for further drying; an air inlet of the circulating fan (202) is connected with the lower part of the front section of the belt dryer (201), an air outlet of the circulating fan is connected with an air inlet of the condensed water heat exchanger (204), a water inlet of the condensed water heat exchanger (204) is connected with an outlet of the condensed water pump (107), an air outlet of the condensed water heat exchanger (204) is positioned at the upper part of the rear section of the belt dryer (201) and is used for enabling kiln head hot air to be sent into the belt dryer (201) from the rear section of the belt dryer (201), and a water outlet of the condensed water heat exchanger (204) is connected with the deaerator (507); the condensed water heat exchanger (204) is used for exchanging heat between condensed water discharged by the condensed water pump (107) and kiln head hot air after heating the granulated sludge; the exhaust fan (203) is arranged at an air outlet at the lower part of the rear section of the belt dryer (201); the outlet of the exhaust fan (203) is connected to a pipeline between the drying gas exhaust fan (109) and the high-temperature section of the grate cooler (502); an air outlet of the drying air exhaust fan (109) is connected with an air inlet of the grate cooler (502); the tail end of the belt dryer (201) is connected with the inlet of the dry sludge bin (205);

the precombustion system comprises a second sludge conveyor (401), a dosing machine (402) and a precombustion furnace (403); a branch pipe (405) connected with the precombustion furnace (403) is arranged on the tertiary air pipe; an inlet of the second sludge conveyor (401) is connected with an outlet of the dry sludge bin (205), the outlet is connected with an inlet of the quantitative feeder (402), and an outlet of the quantitative feeder (402) is connected with the precombustor (403); the pre-burning furnace is used for pre-burning the dry sludge by contacting with high-temperature air of a grate cooler led out by a tertiary air pipe (508); the pre-burning furnace (403) is connected with the decomposing furnace (501) and is used for conveying high-temperature flue gas and ash slag generated after pre-burning into the decomposing furnace (501);

the waste gas treatment system comprises a waste gas exhaust fan (301), a first air quantity regulating valve (302), a second air quantity regulating valve (303), an emergency deodorizing system (304) and a connecting pipeline; the exhaust gas exhaust fan (301) is respectively communicated with the sludge storage workshop and the sludge drying workshop, and an outlet of the exhaust gas exhaust fan (301) is respectively connected with the first air quantity regulating valve (302) and the second air quantity regulating valve (303); the outlet of the first air quantity regulating valve (302) is connected with a pipeline between the drying air exhaust fan (109) and the high temperature section of the grate cooler (502), and the second air quantity regulating valve (303) is connected with the emergency deodorizing system (304).

2. The municipal sludge drying and cement production line coupling system according to claim 1, wherein a fifth air quantity adjusting valve (404) for adjusting the air quantity entering the precombustor (403) is arranged on the branch pipe (405).

3. The municipal sludge drying and cement production line coupling system according to claim 1, wherein the co-treatment system further comprises a third air volume control valve (504) arranged on a connecting pipeline between an outlet of the kiln head exhaust fan (503) and the upper part of the front section of the belt dryer (201), and a fourth air volume control valve (505) arranged on a connecting pipeline between an outlet of the kiln head exhaust fan (503) and the chimney; the kiln head exhaust fan (503) is used for leading out hot air in the grate cooler (502) and then sending the hot air into the belt dryer (201) through the third air quantity regulating valve (504), and redundant exhaust air is regulated by the fourth air quantity regulating valve (505) and is exhausted into the chimney (506).