System and working method for resource utilization of sludge coupled with wooden formwork of construction site

Abstract

The application provides a sludge coupling building site wooden template resource utilization system and working method, which can realize collaborative resource utilization of two different materials and flue gas reaching ultra-clean emission requirements. A first high-pressure vertical dehydration device, a second steam drying device and a dry sludge temporary storage are connected in sequence, and the dry sludge temporary storage is connected with a incinerator; a first crushing and iron removing system, a second crushing and iron removing system and a third crushing system are connected in sequence, and the third crushing system is connected with the incinerator; the incinerator is connected with a steam turbine generator set and a dry desulfurization system, and the steam turbine generator set is connected with the second steam drying device; the dry desulfurization system, an SNCR denitration system, a metal filter dust collector, an SCR denitration system, a dry deacidification system, an activated carbon injection system and a bag-type dust collector are connected in sequence; and a multi-medium heat exchange device is connected with the bag-type dust collector, a wet deacidification system, the incinerator, the metal filter dust collector and the second steam drying device.

Description

Technical Field

[0001] This invention relates to a resource utilization system and working method for sludge coupled with wooden formwork on construction sites. Background Technology

[0002] Municipal sludge treatment and disposal, as a crucial component of urban solid waste management, is mandated by national plans to achieve a harmless treatment rate of over 90%. Among numerous sludge disposal methods, sludge incineration technology, characterized by its harmlessness, volume reduction, and resource recovery, has become a nationally encouraged approach. From 2019 to 2021, incineration-based treatment processes accounted for over 65% of newly constructed sludge disposal projects. However, municipal sludge is characterized by its low calorific value and seasonal fluctuations, posing significant challenges to self-sustaining incineration. Therefore, auxiliary fuel is typically added to the sludge incinerator to ensure its proper operation.

[0003] Wooden formwork from construction sites has always been a significant component of urban solid waste. Untreated wooden formwork, scattered and piled up, not only affects the city's appearance but also represents a "misplaced resource" that fails to be fully utilized. However, due to the low calorific value, high ash content, and high moisture content of sludge, and the numerous impurities in construction site wooden formwork, along with the corrosive substances in the formwork adhesive, co-incinerating sludge and construction site wooden formwork presents different challenges compared to conventional independent sludge incineration. These challenges include different treatment requirements in the fuel drying pretreatment stage, as well as differences in the incineration and flue gas purification stages compared to independent incineration projects. Therefore, a resource utilization technology for the co-incineration of sludge and construction site wooden formwork is urgently needed. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned shortcomings in the prior art and to provide a resource utilization system and working method for sludge coupled with wooden formwork on construction sites with a reasonable structural design. The system couples drying, incineration and flue gas purification processes, which can realize the synergistic resource utilization of two different materials and achieve ultra-clean emission requirements for flue gas.

[0005] The technical solution adopted by this invention to solve the above problems is: a resource utilization system for sludge coupled with wooden formwork at construction sites, characterized by: including a primary high-pressure vertical dewatering device, a secondary steam drying device, a dry sludge temporary storage silo, a primary crushing and iron removal system, a secondary crushing and iron removal system, a tertiary crushing system, an incinerator, a steam turbine generator set, a dry desulfurization system, an SNCR denitrification system, a metal cartridge dust collector, an SCR denitrification system, a dry deacidification system, an activated carbon injection system, a bag filter, a multi-media heat exchanger, and a wet deacidification system; the primary high-pressure vertical dewatering device includes a secondary steam drying device, a secondary steam drying device, a dry sludge temporary storage silo, a primary crushing and iron removal system, a secondary crushing and iron removal system, a tertiary crushing system, an incinerator, a steam turbine generator set, a dry desulfurization system, an SNCR denitrification system, a metal cartridge dust collector, an SCR denitrification system, a dry deacidification system, an activated carbon injection system, a bag filter, a multi-media heat exchange device, and a wet deacidification system; the primary high-pressure vertical dewatering device includes a secondary steam drying device, a secondary steam drying device, a secondary steam drying device, a secondary steam drying device, a tertiary ... a tertiary steam drying device, a tertiary steam drying device, a tertiary steam drying device, a tertiary steam drying device, a secondary high-pressure vertical dewatering device, a secondary steam drying device, a secondary steam drying device, a tertiary steam drying device, a tertiary steam drying device, a tertiary steam drying The vertical dewatering unit, secondary steam drying unit, and dry sludge storage silo are connected in sequence, and the dry sludge storage silo is connected to the sludge feed inlet of the incinerator; the primary crushing and iron removal system, secondary crushing and iron removal system, and tertiary crushing system are connected in sequence, and the tertiary crushing system is connected to the wood feed inlet of the incinerator; the steam outlet of the incinerator is connected to the steam inlet of the steam turbine generator set, and the steam extraction port of the steam turbine generator set is connected to the steam inlet of the secondary steam drying unit; the flue gas outlet of the incinerator is connected to the dry desulfurization system, the SNCR denitrification system, and the metal filter cartridge. The dust collector, SCR denitrification system, dry acid removal system, activated carbon injection system, and bag filter are connected in sequence; the multi-media heat exchange device includes a main heat exchanger, a bypass heat exchanger, switching valve one, and switching valve two; the main heat exchanger is equipped with a flue gas flow channel, a combustion air flow channel, a compressed air flow channel, and a condensate flow channel, wherein the flue gas flow channel is a hot fluid flow channel, and the combustion air flow channel, compressed air flow channel, and condensate flow channel are all cold fluid flow channels; the inlet of the flue gas flow channel is connected to the bag filter, and the outlet is connected to the flue gas inlet of the wet acid removal system; the combustion air flow channel... The outlet is connected to the air inlet of the incinerator; the outlet of the compressed air channel is divided into two paths, one of which is connected to the cold flow channel inlet of the bypass heat exchanger through switching valve two, and the other of which is connected to the compressed air inlet of the metal cartridge dust collector through switching valve one; the inlet of the condensate channel is connected to the condensate outlet of the secondary steam drying equipment, and the outlet is connected to the inlet of the hot fluid channel of the bypass heat exchanger; the outlet of the hot fluid channel of the bypass heat exchanger is connected to the demineralized water inlet of the steam turbine generator set; and the outlet of the cold flow channel of the bypass heat exchanger is connected to the compressed air inlet of the metal cartridge dust collector.

[0006] The present invention also includes a wet sludge temporary storage and receiving bin, the sludge outlet of which is connected to the sludge inlet of a primary high-pressure vertical dewatering device.

[0007] The sludge outlet of the dry sludge temporary storage facility described in this invention is connected to the sludge feed port of the incinerator via a dry sludge scraper conveying device.

[0008] The invention also includes a chimney, and the flue gas outlet of the wet desulfurization system is connected to the chimney.

[0009] The main heat exchanger described in this invention is a shell-and-tube heat exchanger.

[0010] The secondary steam drying equipment described in this invention uses a disc dryer, a paddle dryer, or a thin-layer dryer.

[0011] The incinerator described in this invention is a circulating fluidized bed furnace type with a cyclone separator.

[0012] The working method of the sludge-coupled resource utilization system for wooden formwork at construction sites is characterized by the following processes:

[0013] I. Pretreatment of wet sludge, including the following steps:

[0014] (1) The wet sludge is fed into a primary high-pressure vertical dewatering device for primary pressure filtration;

[0015] (2) The sludge after primary filter press enters the secondary steam drying equipment for secondary drying;

[0016] (3) The dried sludge after secondary drying needs to be temporarily stored in a dry sludge storage warehouse;

[0017] II. Pre-treatment of wooden formwork at construction sites, including the following steps:

[0018] Wooden formwork at construction sites first enters the primary crushing and iron removal system for primary crushing and iron removal, then enters the secondary crushing and iron removal system for secondary crushing and iron removal, and finally enters the tertiary crushing system for tertiary crushing.

[0019] 3. After pretreatment, the sludge is transported to the incinerator and co-incinerated with the pretreated wooden formwork materials from the construction site.

[0020] IV. The incinerator produces high-quality steam, which drives a steam turbine generator set to generate electricity; the steam extracted by the steam turbine generator set enters a secondary steam drying equipment for secondary drying of sludge.

[0021] 5. The flue gas from the incinerator passes sequentially through the desulfurization of the dry desulfurization system, the SNCR denitrification of the SNCR denitrification system, the dust removal of the metal cartridge dust collector, the SCR denitrification of the SCR denitrification system, the dry desulfurization of the dry desulfurization system, the heavy metal removal of the activated carbon injection system, and the bag dust removal of the bag filter. After being cooled in the flue gas duct of the main heat exchanger, it is sent to the wet desulfurization system for the final wet desulfurization treatment.

[0022] In the multi-media heat exchanger, combustion air is introduced into the inlet of the combustion air channel. After heat exchange, the combustion air is heated and then enters the incinerator. The condensate from the secondary steam drying equipment enters the condensate channel. After heat exchange, the condensate is heated and then enters the hot fluid channel of the bypass heat exchanger, and then enters the steam turbine generator set. Under normal operating conditions, switching valve two is closed and switching valve one is opened, and compressed air is introduced into the inlet of the compressed air channel. After heat exchange and heating in the main heat exchanger, the compressed air enters the metal cartridge dust collector. Under startup conditions, switching valve two is opened and switching valve one is closed, and compressed air is introduced into the inlet of the compressed air channel. After heat exchange and heating in the main heat exchanger, the compressed air enters the bypass heat exchanger and heats up by exchanging heat with the condensate, and then enters the metal cartridge dust collector.

[0023] In the multi-media heat exchange device of the present invention, under normal operating conditions, the temperature of the combustion air rises from 20°C to 70°C after heat exchange, the temperature of the condensate rises from 130°C to 150°C after heat exchange, the temperature of the compressed air rises from 20°C to 120°C after heat exchange, and the temperature of the flue gas decreases from 160°C to 80°C after heat exchange.

[0024] The temperature operating window of the metal cartridge dust collector described in this invention is 380℃-420℃, and the temperature operating window of the SCR denitrification system is 370℃-380℃.

[0025] Compared with the prior art, the present invention has the following advantages and effects:

[0026] 1. The coupled drying, incineration, and flue gas purification processes can achieve the synergistic resource utilization of two different materials, sludge and wooden formwork from construction sites, and ensure that the flue gas meets ultra-clean emission requirements. This achieves material synergy and energy coupling, and realizes the goals of environmental protection, high efficiency, energy saving, and stable operation.

[0027] 2. The sludge adopts a two-stage dewatering technology. The first stage is a high-pressure vertical process that does not require the addition of chemical modifiers. The second stage uses indirect steam heating, which greatly reduces the energy consumption for sludge drying compared to direct heating of the sludge.

[0028] 3. The wooden formwork at the construction site adopts a three-stage pretreatment process: primary crushing and iron removal, secondary crushing and iron removal, and tertiary crushing. After the above stages, the particle size of the formwork entering the furnace can be uniformly within 2cm×1cm, and the metal content is <0.1%.

[0029] 4. The flue gas purification process adopts an 8-step route: "in-furnace desulfurization + in-furnace SNCR denitrification + high-temperature metal cartridge dust removal + high-temperature SCR denitrification + dry acid removal + activated carbon injection for heavy metal removal + low-temperature bag filter dust removal + wet acid removal," which can achieve ultra-clean emissions of flue gas: the dust emission concentration can be controlled at 3 mg / Nm³. 3 Within this range, SO2 emission concentration can be controlled at 20 mg / Nm³. 3HCl emission concentration can be controlled at 10 mg / Nm³. 3 NOx emission concentration can be controlled at 50 mg / Nm³. 3 .

[0030] 5. This invention utilizes a multi-medium heat exchange device as a key element to achieve four objectives: flue gas energy recovery, energy absorption of steam and water working fluids to improve thermal efficiency, compressed air heat exchange to raise the temperature and protect the high-temperature metal filter device, and increasing the temperature of the combustion air to improve efficiency. This enables the recovery of waste heat and stable operation of the equipment. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention.

[0032] Figure 2 This is a schematic diagram of the structure of the multi-medium heat exchanger according to an embodiment of the present invention. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The following embodiments are explanations of the present invention, but the present invention is not limited to the following embodiments.

[0034] The sludge-coupled resource utilization system for wooden formwork at construction sites according to an embodiment of the present invention includes a wet sludge temporary storage receiving bin 1, a primary high-pressure vertical dewatering device 2, a secondary steam drying device 3, a dry sludge temporary storage bin 4, a dry sludge scraper conveyor 5, a primary crushing and iron removal system 7, a secondary crushing and iron removal system 8, a tertiary crushing system 9, an incinerator 6, a steam turbine generator set 10, a dry desulfurization system 11, an SNCR denitrification system 12, a metal cartridge dust collector 13, an SCR denitrification system 14, a dry deacidification system 15, an activated carbon injection system 16, a bag filter dust collector 17, a multi-media heat exchange device 18, a wet deacidification system 19, and a chimney 20.

[0035] The sludge outlet of the wet sludge temporary storage receiving bin 1 is connected to the sludge inlet of the primary high-pressure vertical dewatering equipment 2. The sludge outlet of the primary high-pressure vertical dewatering equipment 2 is connected to the sludge inlet of the secondary steam drying equipment 3. The sludge outlet of the secondary steam drying equipment 3 is connected to the sludge inlet of the dry sludge temporary storage bin 4. The sludge outlet of the dry sludge temporary storage bin 4 is connected to the sludge feed port of the incinerator 6 through the dry sludge scraper conveying equipment 5.

[0036] The crushed material outlet of the primary crushing and iron removal system 7 is connected to the inlet of the secondary crushing and iron removal system 8. The crushed material outlet of the secondary crushing and iron removal system 8 is connected to the inlet of the tertiary crushing system 9. The crushed material outlet of the tertiary crushing system 9 is connected to the wood feed port of the incinerator 6.

[0037] The steam outlet of the incinerator 6 is connected to the steam inlet of the steam turbine generator set 10, and the steam extraction port of the steam turbine generator set 10 is connected to the steam inlet of the secondary steam drying equipment 3.

[0038] The flue gas outlet of incinerator 6 is connected to the flue gas inlet of dry desulfurization system 11. The flue gas outlet of dry desulfurization system 11 is connected to the flue gas inlet of SNCR denitrification system 12. The flue gas outlet of SNCR denitrification system 12 is connected to the flue gas inlet of metal cartridge dust collector 13. The flue gas outlet of metal cartridge dust collector 13 is connected to the flue gas inlet of SCR denitrification system 14. The flue gas outlet of SCR denitrification system 14 is connected to the flue gas inlet of dry acid removal system 15. The flue gas outlet of dry acid removal system 15 is connected to the flue gas inlet of activated carbon injection system 16. The flue gas outlet of activated carbon injection system 16 is connected to the flue gas inlet of bag filter 17.

[0039] The multi-media heat exchange device 18 includes a main heat exchanger 181, a bypass heat exchanger 182, a first switching valve 183, and a second switching valve 184.

[0040] The main heat exchanger 181 is a shell-and-tube heat exchanger. The main heat exchanger 181 is provided with a flue gas flow channel 1811, a combustion air flow channel 1812, a compressed air flow channel 1813, and a drain channel 1814. Among them, the flue gas flow channel 1811 is a hot fluid flow channel, while the combustion air flow channel 1812, the compressed air flow channel 1813, and the drain channel 1814 are all cold fluid flow channels. The flue gas flows through the shell side, while the other three media flow through the tube side.

[0041] The inlet of flue gas duct 1811 is connected to the flue gas outlet of bag filter 17, the outlet of flue gas duct 1811 is connected to the flue gas inlet of wet acid removal system 19, and the flue gas outlet of wet acid removal system 19 is connected to chimney 20. The inlet of the combustion air channel 1812 is used to supply combustion air, and the outlet of the combustion air channel 1812 is connected to the air inlet of the incinerator 6; the inlet of the compressed air channel 1813 is used to supply compressed air, and the outlet of the compressed air channel 1813 is divided into two paths, one path is connected to the cold flow channel inlet of the bypass heat exchanger 182 through switching valve 2 184, and the other path is connected to the compressed air inlet of the metal cartridge dust collector 13 through switching valve 1 183; the inlet of the condensate channel 1814 is connected to the condensate outlet of the secondary steam drying equipment 3, the outlet of the condensate channel 1814 is connected to the inlet of the hot fluid channel of the bypass heat exchanger 182, the outlet of the hot fluid channel is connected to the demineralized water inlet of the steam turbine generator set 10, and the cold flow channel outlet of the bypass heat exchanger 182 is connected to the compressed air inlet of the metal cartridge dust collector 13.

[0042] The working method of the sludge-coupled construction site wooden formwork resource utilization system according to an embodiment of the present invention includes the following process:

[0043] Before being incinerated, wet sludge and wooden formwork from construction sites must undergo fuel pretreatment.

[0044] I. The pretreatment of wet sludge includes the following steps:

[0045] (1) The wet sludge is transported to the plant in a closed tanker truck and first sent to the wet sludge temporary storage receiving bin 1. A 50×50 grid is installed above the temporary storage receiving bin to filter out large debris in the sludge and avoid affecting the normal operation of the downstream equipment. The wet sludge with 80% moisture content is sent to the downstream drying equipment through the plunger pump at the bottom of the receiving bin.

[0046] (2) The sludge in the wet sludge temporary storage receiving bin 1 is sent to the primary high-pressure vertical dewatering equipment 2 for primary filter press. This equipment is different from the traditional plate and frame filter press. The sludge does not need to be diluted with water or modified with chemicals. The sludge with 80% moisture content is directly pressed after being clothed. The power for the filter press comes from hydraulic pressure, ensuring uniform stress throughout the entire filter press area. After the primary filter press, the moisture content of the sludge can be reduced from 80% to 65%, which can greatly reduce the energy consumption of subsequent steam drying and achieve energy saving and efficiency improvement for the entire plant.

[0047] (3) The sludge after primary filter pressing enters the secondary steam drying equipment 3 for secondary drying. The secondary steam drying equipment 3 can adopt the industry-standard disc dryer, paddle dryer, or thin-layer dryer. The sludge moisture content can be further reduced from 65% to 40%. The steam required by the secondary steam drying equipment 3 comes from the steam generated after coupled incineration. Due to the primary high-pressure vertical dewatering process, the steam energy consumption of secondary drying and dewatering is greatly reduced, and the amount of steam generated by the whole plant can be much greater than the steam energy consumption.

[0048] (4) The dried sludge after secondary drying needs to be temporarily stored in the dry sludge temporary storage silo 4. This can isolate the drying process section from the incineration process section and achieve a buffer between the two. When a process section fails, it will not affect the operation of the other process section for a short period of time.

[0049] II. Wooden formwork from construction sites cannot be directly incinerated in the furnace. Firstly, this type of material is bulky and cannot be fully burned in incinerator 6. Secondly, the formwork contains metal materials such as nails and iron sheets, which will wear down the heated surfaces over time and affect the normal ash discharge of incinerator 6. Therefore, wooden formwork from construction sites must undergo pretreatment before being put into the furnace. The pretreatment of wooden formwork from construction sites includes the following steps:

[0050] This invention employs a three-stage pretreatment process: wooden formwork from construction sites first enters the primary crushing and iron removal system 7 for primary crushing and iron removal, then enters the secondary crushing and iron removal system 8 for secondary crushing and iron removal, and finally enters the tertiary crushing system 9 for tertiary crushing. After these stages, the particle size of the wood entering the furnace can be uniformly within 2cm × 1cm, with a metal content of <0.1%. This process can also recover a large amount of scrap metal, which can be recycled and reused in the market, realizing a circular economy of resources.

[0051] 3. After pretreatment, the dry sludge with a moisture content of 40% is conveyed to the incinerator 6 via the sludge scraper conveyor 5, where it is co-incinerated with the pretreated wooden formwork material from the construction site. The sludge scraper conveyor 5 is equipped with a metal scraper, and the parts of the sludge scraper conveyor 5 that come into contact with the sludge are made of SUS30408 ​​material, with a polytetrafluoroethylene (PTFE) lining at the bottom for enhanced corrosion resistance.

[0052] Sludge and crushed formwork timber are fed into incinerator 6 for incineration through different feed ports. The different feed port settings can effectively control the amount of different materials processed, improve system flexibility, and eliminate the need for thorough material mixing at the front end, thus simplifying the system process.

[0053] Sludge and construction site timber formwork materials are co-incinerated in incinerator 6. The design of incinerator 6 is crucial to the entire coupled resource utilization process: on the one hand, it needs to ensure the complete combustion of different materials; on the other hand, it needs to precisely control the furnace temperature to meet the environmental requirement of 850℃ while avoiding high-temperature coking. Therefore, this invention recommends using a circulating fluidized bed furnace with a cyclone separator. This furnace can return larger combustible particles in the flue gas to the furnace for secondary combustion through cyclone separation, ensuring multiple cycles and thorough combustion of difficult-to-burn materials. Furthermore, by adjusting the volume and temperature of the secondary air, the furnace temperature can be controlled within the range of 850℃ to 900℃, achieving efficient and precise temperature control.

[0054] Fourth, the incinerator 6 produces high-quality steam after incineration. The steam drives the turbine generator set 10 to generate electricity, realizing the resource utilization of solid waste. On the other hand, the turbine generator set 10 is equipped with a low-quality steam extraction port, which extracts steam to enter the secondary steam drying equipment 3 for secondary drying of sludge.

[0055] Fifth, the flue gas after incineration contains a large amount of harmful substances such as dust, sulfur dioxide, and NOx. According to environmental protection requirements, it must be thoroughly treated before it can be discharged. This invention patent provides an 8-stage series high-efficiency flue gas purification system, which can achieve ultra-clean emissions of flue gas.

[0056] The flue gas from incinerator 6 passes sequentially through the in-furnace desulfurization of dry desulfurization system 11, the in-furnace SNCR denitrification of SNCR denitrification system 12, the dust removal of metal cartridge dust collector 13, the high-temperature SCR denitrification of SCR denitrification system 14, the dry denitrification of dry acid removal system 15, the activated carbon injection system 16 for activated carbon injection to remove heavy metals, and the low-temperature bag dust removal of bag dust collector 17. After entering the flue gas flow channel 1811 of the main heat exchanger 181 for cooling, the flue gas at about 80°C is sent to the wet denitrification system 19 for final wet denitrification treatment, and then sent to the chimney 20 for discharge.

[0057] In the multi-medium heat exchanger 18, the heat exchange medium of the main heat exchanger 181 is of four types: condensate, compressed air, combustion air, and flue gas. Under normal operating conditions: combustion air is introduced into the inlet of the combustion air channel 1812, and its temperature rises from about 20°C to about 70°C after heat exchange, before entering the incinerator 6; condensate from the secondary steam drying equipment 3 enters the condensate channel 1814, and its temperature rises from about 130°C to about 150°C after heat exchange, before entering the hot fluid channel of the bypass heat exchanger 182 and then entering the turbine generator set 10. Flue gas enters the flue gas channel 1811, and its temperature drops from about 160°C to about 80°C after heat exchange.

[0058] Considering that the flue gas temperature does not reach 160℃ under system startup conditions, but the compressed air used to blow the high-temperature metal filter cartridges of the metal cartridge dust collector 13 must be above 100℃, a bypass heat exchanger 182 is installed between the condensate and the compressed air as a secondary system of this multi-media heat exchange device. Under normal operating conditions, switching valve 2 184 is closed and switching valve 1 183 is opened, and compressed air at approximately 20℃ is introduced into the inlet of the compressed air channel 1813. After the compressed air passes through the main heat exchanger 181 and its temperature rises to approximately 120℃, it enters the metal cartridge dust collector 13. Under startup conditions, switching valve 2 184 is opened and switching valve 1 183 is closed, and compressed air at approximately 20℃ is introduced into the inlet of the compressed air channel 1813. After passing through the main heat exchanger 181 and its temperature rises to approximately 120℃, the compressed air then enters the bypass heat exchanger 182 and exchanges heat with the condensate, before entering the metal cartridge dust collector 13. The staged use of hydrophobic, compressed air, and combustion air fully utilizes the energy of the flue gas.

[0059] Using this system, the flue gas from the coupled incineration of sludge and wooden formwork at construction sites can achieve ultra-clean emissions: the dust emission concentration can be controlled at 3 mg / Nm³. 3 Within this range, SO2 emission concentration can be controlled at 20 mg / Nm³. 3 HCl emission concentration can be controlled at 10 mg / Nm³. 3 NOx emission concentration can be controlled at 50 mg / Nm³. 3 This will achieve a new level of control over pollutants in the industry.

[0060] The entire flue gas treatment system is built around a metal cartridge dust collector 13, a first in the sludge and solid waste industry. Compared to traditional baghouse dust collectors, this invention, by adding the metal cartridge dust collector 13, can reduce the dust concentration from 80g / Nm3 to 3mg / Nm3 at a temperature of around 400℃, achieving a dust removal efficiency of 99.99%. Through high-temperature dust removal, alkali metal atoms originally attached to the dust in the flue gas are also removed, allowing the downstream flue gas to utilize a low-investment, low-cost high-temperature SCR process.

[0061] Key parameters:

[0062] The temperature operating window of the metal cartridge dust collector 13 is 380℃-420℃, within which a large amount of dust can be captured.

[0063] The SCR denitrification system 14 operates within a temperature window of 370℃-380℃. At this temperature, the denitrification catalyst exhibits the strongest activity and achieves the highest denitrification efficiency. Unlike the conventional low-temperature SCR denitrification process used in the industry, the process employed in this invention eliminates the process of cooling and then reheating the flue gas, resulting in energy savings of over 80% and extending catalyst lifespan from the conventional 6 months to over 5 years.

[0064] The flue gas after high-temperature SCR undergoes further heat exchange and cooling, with the flue gas at approximately 160°C exiting the boiler and being fed into the dry deacidification and activated carbon injection heavy metal removal process section. It is then sent to a low-temperature bag filter for further dust removal from the drying and activated carbon injection processes. After passing through a multi-media heat exchanger 18, the flue gas at approximately 80°C is sent to the wet deacidification system 19 for final deacidification treatment.

[0065] Furthermore, it should be noted that the specific embodiments described in this specification may differ in the shape and name of their components, etc. The above description is merely illustrative of the structure of the present invention. All equivalent or simple variations made based on the structure, features, and principles described in this patent concept are included within the protection scope of this patent. Those skilled in the art can make various modifications or additions to the described specific embodiments or use similar methods to substitute them, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, all of which should fall within the protection scope of this invention.

Claims

1. A resource recovery system for coupling sludge to wooden formwork at a construction site, characterized by: The application relates to a wet sludge treatment system, which comprises a first-stage high-pressure vertical dewatering device, a second-stage steam drying device, a dry sludge temporary storage, a first-stage crushing and iron-removing system, a second-stage crushing and iron-removing system, a third-stage crushing system, a burning furnace, a steam turbine generator set, a dry desulfurization system, an SNCR denitration system, a metal filter dust collector, an SCR denitration system, a dry deacidification system, an activated carbon injection system, a bag-type dust collector, a multi-medium heat exchange device and a wet deacidification system; the first-stage high-pressure vertical dewatering device, the second-stage steam drying device and the dry sludge temporary storage are sequentially connected, the dry sludge temporary storage is connected with a sludge feeding port of the burning furnace; the first-stage crushing and iron-removing system, the second-stage crushing and iron-removing system and the third-stage crushing system are sequentially connected, the third-stage crushing system is connected with a wood material feeding port of the burning furnace; a steam outlet of the burning furnace is connected with a steam inlet of the steam turbine generator set, and a steam extraction port of the steam turbine generator set is connected with a steam inlet of the second-stage steam drying device; a flue gas outlet of the burning furnace is connected with the dry desulfurization system, and the dry desulfurization system, the SNCR denitration system, the metal filter dust collector, the SCR denitration system, the dry deacidification system, the activated carbon injection system and the bag-type dust collector are sequentially connected; the multi-medium heat exchange device comprises a main-path heat exchanger, a bypass heat exchanger, a switching valve one and a switching valve two; the main-path heat exchanger is provided with a flue gas flow channel, a combustion air flow channel, a compressed air flow channel and a drain flow channel, wherein the flue gas flow channel is a hot fluid flow channel, and the combustion air flow channel, the compressed air flow channel and the drain flow channel are cold fluid flow channels; an inlet of the flue gas flow channel is connected with the bag-type dust collector, and an outlet is connected with a flue gas inlet of the wet deacidification system; an outlet of the combustion air flow channel is connected with an air inlet of the burning furnace; an outlet of the compressed air flow channel is divided into two paths, one path is connected with a cold flow inlet of the bypass heat exchanger through the switching valve two, and the other path is connected with a compressed air inlet of the metal filter dust collector through the switching valve one; an inlet of the drain flow channel is connected with a drain outlet of the second-stage steam drying device, an outlet is connected with a hot fluid flow inlet of the bypass heat exchanger, a hot fluid flow outlet of the bypass heat exchanger is connected with a desalted water inlet of the steam turbine generator set, and a cold flow outlet of the bypass heat exchanger is connected with a compressed air inlet of the metal filter dust collector.

2. The resource recovery system for sludge coupled construction site wood formwork according to claim 1, characterized in that: The system further comprises a wet sludge temporary storage receiving bin, and a sludge outlet of the wet sludge temporary storage receiving bin is connected with a sludge inlet of the first-stage high-pressure vertical dewatering device.

3. The resource recovery system for sludge coupled construction site wood formwork according to claim 1, characterized in that: A sludge outlet of the dry sludge temporary storage is connected with a sludge feeding port of the burning furnace through a dry sludge scraper conveying device.

4. The resource recovery system for sludge coupled construction site wood formwork according to claim 1, characterized in that: The system further comprises a chimney, and a flue gas outlet of the wet deacidification system is connected with the chimney.

5. The resource recovery system for sludge coupled construction site wood formwork according to claim 1, wherein: The main-path heat exchanger is a tube-shell heat exchanger.

6. The resource recovery system for sludge coupled construction site wood formwork according to claim 1, characterized in that: The second-stage steam drying device adopts a disc dryer, a paddle dryer or a thin-layer dryer.

7. The resource recovery system for sludge coupled construction site wood formwork according to claim 1, characterized in that: The burning furnace adopts a circulating fluidized bed furnace type with a cyclone separator.

8. The method of operation of a resource recovery system for sludge coupled construction site wood formwork of any one of claims 1 to 7, characterized in that: The system comprises the following processes: I. Wet sludge pretreatment, comprising the following steps: (1) wet sludge is sent into the first-stage high-pressure vertical dewatering device for first-stage pressure filtration; (2) the sludge after the first-stage pressure filtration is sent into the second-stage steam drying device for second-stage drying; (3) the dry sludge after the second-stage drying is sent into the dry sludge temporary storage for temporary storage; II. Building site wood template mud pretreatment, comprising the following steps: The building site wooden template first enters a first-stage crushing and iron-removing system to be crushed and have iron removed, then enters a second-stage crushing and iron-removing system to be crushed and have iron removed, and then enters a third-stage crushing system to be crushed; III. After the pretreatment, the sludge is transported to the incinerator and incinerated together with the pretreated building site wooden template raw material; IV. The incinerator incinerates to produce high-quality steam, which drives the steam turbine generator set to generate electricity; the steam extracted by the steam turbine generator set enters the secondary steam drying equipment for secondary drying of the sludge; V. The flue gas of the incinerator successively passes through desulfurization of the dry desulfurization system, SNCR denitration of the SNCR denitration system, dust removal of the metal filter dust collector, SCR denitration of the SCR denitration system, dry deacidification of the dry deacidification system, heavy metal removal of the activated carbon injection system, bag dust removal of the bag dust removal system, and then enters the flue gas flow channel of the main heat exchanger for cooling, and is sent into the wet deacidification system for the final wet deacidification treatment; In the multi-medium heat exchange device, combustion-supporting air is sent into the inlet of the combustion-supporting air flow channel, the combustion-supporting air is heated after heat exchange, and then enters the incinerator; drain water of the secondary steam drying equipment enters the drain water flow channel, the drain water is heated after heat exchange, and then enters the hot fluid flow channel of the bypass heat exchanger, and then enters the steam turbine generator set; under normal working conditions, the switching valve two is closed and the switching valve one is opened, compressed air is sent into the inlet of the compressed air flow channel, and the compressed air is heated after heat exchange in the main heat exchanger and then enters the metal filter dust collector; under starting working conditions, the switching valve two is opened and the switching valve one is closed, compressed air is sent into the inlet of the compressed air flow channel, the compressed air is heated after heat exchange in the main heat exchanger, and then heated after heat exchange with the drain water in the bypass heat exchanger, and then enters the metal filter dust collector.

9. The method of working according to claim 8, characterized in that: In the multi-medium heat exchange device, under normal working conditions, the temperature of the combustion-supporting air is increased from 20℃ to 70℃ after heat exchange, the temperature of the drain water is increased from 130℃ to 150℃ after heat exchange, the temperature of the compressed air is increased from 20℃ to 120℃ after heat exchange, and the temperature of the flue gas is decreased from 160℃ to 80℃ after heat exchange.

10. The method of claim 8, wherein: The temperature working window of the metal filter dust collector is 380℃-420℃, and the temperature working window of the SCR denitration system is 370℃-380℃.

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