System and method for co-processing industrial waste plastics and municipal sludge

Abstract

The invention discloses a system for co-processing industrial waste plastics and municipal sludge. The system comprises a waste plastic pyrolysis unit, a unit for preparing ceramic particles from sludge and a brick making unit, the waste plastic pyrolysis unit is used for receiving waste plastic raw materials and performing pyrolysis treatment on the waste plastic raw materials to generate pyrolytic carbon, waste oil, wastewater and high-temperature flue gas, the pyrolytic carbon is used for supplying energy to pyrolytic reaction of the waste plastic raw materials, the waste oil is collected by an oil storage tank, and the wastewater is discharged after being treated to reach the standard; the unit for preparing the ceramsite from the sludge is used for roasting the pellets by taking high-temperature flue gas generated by pyrolytic reaction of the waste plastic raw materials as a heat source to obtain the ceramsite; the raw materials of the pellets are municipal sludge and building spoil; and the brick making unit is used for making bricks by using the ceramsite obtained by the sludge ceramsite making unit. The invention also discloses an industrial waste plastic and municipal sludge co-processing method realized by the system. The waste plastic and the municipal sludge can be subjected to resourceful treatment at the same time, the purposes of treating waste with waste and conducting cooperative treatment are achieved, and the method has wide application prospects.

Description

Technical Field

[0001] This invention belongs to the field of waste treatment technology, specifically relating to a system and method for the co-treatment of industrial waste plastics and municipal sludge. Background Technology

[0002] Industrial enterprises, especially paper mills, generate large amounts of waste plastic solid waste during product manufacturing. With the improvement of relevant national laws and regulations and the gradual perfection of management and control systems, the accumulated waste from these enterprises over the years is increasing. This has led to growing pressure and difficulty for some companies in disposing of paper mill waste and other solid waste. There is an urgent need to construct facilities for the centralized treatment of paper mill waste and other solid waste generated by numerous enterprises, reducing their burden and effort. This project aims to solve the problem of disposing of paper mill waste and other industrial solid waste from industrial enterprises, prevent these wastes from becoming a pollution hazard in Xinxiang City, and alleviate the economic burden of these solid wastes on enterprises.

[0003] With the rapid development of industry and the continuous increase in urban population, the discharge of urban sewage has increased unprecedentedly. During the operation of sewage treatment processes, a portion of the sludge produced is recycled as reactants in biological reactions, while the remaining sludge is discharged outside the system. The amount of this residual sludge is staggering; it has a high water content, large volume, is easily perishable, has a foul odor, and contains large amounts of heavy metals, pathogens, and other toxic and harmful substances. Therefore, if it is discharged directly into the environment without scientific treatment, it will cause significant pollution to surface water bodies, soil, groundwater, and air, adversely affecting human health. Currently, the state has clearly stipulated that municipal sewage sludge and its treated products cannot be used for land application. Therefore, it is essential to treat the sludge to be harmless, reduce its volume, and stabilize it, and to dispose of it properly to avoid secondary pollution to the environment. Using sludge from municipal wastewater treatment plants, construction waste, and general solid waste as main raw materials, along with a certain amount of auxiliary materials and additives, lightweight ceramsite with a certain strength is produced through decarbonization and calcination. This process can consume large quantities of dewatered sludge and is particularly in line with my country's principles of harmlessness, reduction, and resource utilization in solid waste treatment, thus having broad development prospects.

[0004] Therefore, for industrial solid waste, sludge and other waste pollutants generated during the overall development of Xinxiang City, each pollutant has its own separate treatment process. However, the process of making ceramsite from sludge has high energy consumption and low efficiency, resulting in poor economic benefits. At present, there is an urgent need to develop a green, efficient, economic and socially beneficial resource utilization technology for the co-treatment of industrial plastics and municipal sludge. Summary of the Invention

[0005] The purpose of this invention is to overcome the aforementioned shortcomings and provide a system and method for the co-treatment of industrial waste plastics and municipal sewage sludge, solving the current technical problems of high cost and low efficiency in sludge treatment. This invention can simultaneously treat waste plastics and municipal sewage sludge in a resource-efficient manner, achieving the goal of "treating waste with waste and co-treatment," and has broad application prospects.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: A system for the co-processing of industrial waste plastics and municipal sludge includes: a waste plastic pyrolysis unit, a sludge ceramsite production unit, and a brick-making unit; The waste plastic pyrolysis unit receives waste plastic raw materials and pyrolyzes them to generate pyrolysis carbon, waste oil, waste water and high-temperature flue gas. The pyrolysis carbon is used to provide energy for the pyrolysis reaction of the waste plastic raw materials, the waste oil is collected by the oil storage tank, and the waste water is discharged after treatment to meet the standards. The sludge-to-ceramsite unit uses the high-temperature flue gas generated by the pyrolysis reaction of waste plastic raw materials as a heat source to calcine the pellets to obtain ceramsite; the raw materials for the pellets are municipal sludge and construction waste. The brick-making unit uses the expanded clay particles obtained from the sludge expanded clay particle production unit to make bricks.

[0007] Furthermore, the waste plastic pyrolysis unit includes a screening and crushing unit, a drying and magnetic separation unit, a pyrolysis reactor, a gas-solid separation unit, a solid heat carrier furnace, a pyrolysis gas purification unit, an oil-water separation unit, an oil storage tank, and a wastewater treatment unit. The screening and crushing unit receives waste plastic raw materials and screens and crushes them. After screening and crushing, the raw materials enter the drying and magnetic separation unit, which dries and removes metals from the raw materials. After drying and metal removal, the material enters the pyrolysis reactor, where it undergoes a pyrolysis reaction to generate pyrolytic carbon and high-temperature pyrolytic oil and gas. The heat source for the pyrolysis reaction comes from the solid heat carrier in the solid heat carrier furnace. The solid heat carrier and the material are thoroughly mechanically mixed inside the pyrolysis reactor. High-temperature pyrolysis oil and gas enter the pyrolysis gas purification unit for oil and gas cooling and purification. The resulting gas is sent to the solid heat carrier furnace as supplementary fuel. The resulting liquid phase enters the oil-water separation unit for oil-water separation. The resulting oil phase is stored in the oil storage tank. The resulting wastewater enters the sewage treatment unit for treatment and is discharged after meeting the standards. Pyrolytic carbon and the solid heat carrier participating in the pyrolysis reaction are transported to a solid heat carrier furnace, where they are burned to provide heat and generate high-temperature flue gas. The high-temperature flue gas carries the solid heat carrier to a gas-solid separation unit, where the high-temperature flue gas carrying the solid heat carrier undergoes gas-solid separation. The resulting solid phase is returned to the pyrolysis reactor to participate in the pyrolysis reaction, while the resulting gas enters the sludge-to-ceramsite unit as a heat source for calcination of the sludge-to-ceramsite. After being heated in the solid heat carrier furnace, the solid heat carrier enters the pyrolysis reactor as a heat source for the reaction.

[0008] Furthermore, the sludge-to-ceramsite unit includes a pretreatment unit, a proportioning and metering unit, a primary mixing unit, an aging unit, a secondary mixing unit, a granulation and screening unit, a rotary calcining reactor, a supplementary fuel unit, a flue gas purification unit, and a cooling and screening unit. The pretreatment unit receives municipal sludge and construction waste, allowing the municipal sludge and construction waste to dry naturally and evaporate some of the moisture. Municipal sludge and construction waste from the pretreatment unit are respectively output to the primary mixing unit for primary mixing, and the proportioning and metering unit is used to control the proportion of municipal sludge and construction waste. Materials from the primary mixing unit enter the aging unit for aging; Materials from the aging unit enter the secondary mixing unit for secondary mixing; The material from the secondary mixing unit enters the granulation and screening unit for granulation. The granulation and screening unit screens the resulting pellets. The qualified pellets are sent to the rotary roasting reactor, and the unqualified pellets are returned to the secondary mixing unit. The pellets are roasted in a rotary roasting reactor to obtain ceramsite; the roasting heat source of the rotary roasting reactor comes from the high-temperature flue gas generated by the pyrolysis reaction of waste plastic raw materials in the waste plastic pyrolysis unit and the supplementary fuel unit. The ceramsite from the rotary calcining reactor enters the cooling and screening unit. Under the negative pressure of the rotary calcining reactor, cold air is introduced from the discharge end of the cooling and screening unit, and the ceramsite is cooled and discharged. The cold air is heated in the heat exchange process and enters the rotary calcining reactor as high-temperature combustion air. The cooling and screening unit screens the cooled and discharged ceramsite according to its particle size and sends it to different ceramsite bins in the brick making unit for storage. High-temperature flue gas from the rotary roasting reactor enters the flue gas purification unit 2i and is discharged in compliance with emission standards after purification treatment.

[0009] Furthermore, the brick-making unit includes a ceramsite storage and conveying unit, an additive metering unit, a mixing and stirring unit, a foaming unit, a molding unit, a curing unit, a demolding unit, a cutting unit, and a stacking unit. The expanded clay storage and conveying unit is used to store expanded clay of different particle sizes. The expanded clay from the expanded clay storage and conveying unit and the additives from the additive metering unit are sent to the mixing and stirring unit for thorough mixing. The material from the mixing unit passes through the foaming unit, molding unit, curing unit, demolding unit, cutting unit and stacking unit in sequence to obtain finished masonry bricks; the foaming unit, molding unit, curing unit, demolding unit, cutting unit and stacking unit are used to foam, mold, cure, demold, cut and stack the material respectively.

[0010] Furthermore, after the screening and crushing unit screens and crushes the waste plastic raw materials, the particle size of the raw materials is less than 80mm; The drying magnetic separation unit dries and removes metals from the raw materials after screening and crushing. The resulting material has a moisture content of less than 30% and a metal removal rate of more than 95%.

[0011] Furthermore, the pyrolysis reaction temperature range is 400~600℃; The temperature of the solid heat carrier in the solid heat carrier furnace is 800~900℃; When high-temperature pyrolysis oil and gas enter the pyrolysis gas purification unit for cooling and purification, the dust content of the purified oil and gas is less than 2 mg / Nm³. 3 The outlet temperature range of the pyrolysis gas purification unit is 50~100℃.

[0012] Furthermore, construction waste is collected by a loader or grab bucket and fed to a descraper via a box feeder to remove impurities. The waste then enters a double roll crusher for crushing. The crushed material is dried in a dryer and then temporarily stored in a buffer bin. Municipal sludge is stored in a sludge pond, and the odorous gases emitted by the municipal sludge are collected under negative pressure and used as fuel for the rotary roasting reactor.

[0013] Furthermore, the supplementary fuel in the supplementary fuel unit may be one or more of natural gas, biomass fuel, or coal; The roasting temperature of the rotary roasting reactor is 1050~1250℃. The pellets move gradually towards the kiln head as the rotary kiln rotates. The high-temperature flue gas generated by the pyrolysis reaction of waste plastic raw materials or the high-temperature flue gas generated by the combustion of supplementary fuel flows from the kiln head to the kiln tail, opposite to the direction of the pellet movement. During the movement, the ceramsite exchanges heat with the high-temperature flue gas, and finally forms ceramsite.

[0014] Furthermore, the additives include one or more of the following: silicate cementitious agents, fly ash, fine stone powder, sand or tailings slag powder. The curing time for the curing unit is 6-12 hours, and the curing temperature is 20-60℃.

[0015] A method for co-treating industrial waste plastics and municipal sewage sludge, implemented using the aforementioned system for co-treating industrial waste plastics and municipal sewage sludge, includes: The waste plastic pyrolysis unit receives waste plastic raw materials and pyrolyzes them to generate pyrolysis carbon, waste oil, waste water and high-temperature flue gas. The pyrolysis carbon is used to provide energy for the pyrolysis reaction of the waste plastic raw materials, the waste oil is collected by the oil storage tank, and the waste water is discharged after treatment to meet the standards. The sludge-to-ceramsite unit uses the high-temperature flue gas generated by the pyrolysis reaction of waste plastic raw materials as a heat source to calcine the pellets to obtain ceramsite; the raw materials for the pellets are municipal sludge and construction waste. The brick-making unit uses the expanded clay particles obtained from the sludge expanded clay particle production unit to make bricks.

[0016] Compared with the prior art, the present invention has at least one of the following advantages: (1) The present invention can simultaneously treat waste plastics and municipal sludge in a resource-efficient manner, achieving the goal of “treating waste with waste and co-processing”; (2) The present invention uses the high-temperature flue gas generated by the waste plastic pyrolysis unit as the heat source of the sludge to ceramsite unit, which realizes the full utilization of system energy and the high energy utilization rate of the process system; (3) The blocks produced by the waste plastic pyrolysis unit and the fuel oil and brick making unit of this invention can all be sold externally, which is a good economic prospect; (4) The waste plastic pyrolysis unit of the present invention ensures a closed and oxygen-free reaction atmosphere during the process of treating waste plastics, which fundamentally eliminates the generation of dioxins and has a good environmental protection effect. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a method for the co-treatment of industrial waste plastics and municipal sludge according to the present invention; In the diagram: 1- Waste plastic pyrolysis unit, 2- Sludge ceramsite production unit, 3- Brick making unit; 1a-Screening and crushing unit, 1b-Drying and magnetic separation unit, 1c-Pyrolysis reactor unit, 1e-Gas-solid separation unit, 1d-Solid heat carrier furnace, 1f-Pyrolysis gas purification unit, 1g-Oil-water separation unit, 1h-Oil storage tank, 1i-Wastewater treatment unit; 2a-Pretreatment unit, 2b-Proportioning and metering unit, 2c-Primary mixing unit, 2d-Aging unit, 2e-Secondary mixing unit, 2f-Pelletizing and screening unit, 2g-Rotary roasting reactor, 2h-Supplementary fuel unit, 2i-Fluorescence purification unit, 2j-Cooling and screening unit; 3a-Ceramic granule storage and conveying unit, 3b-Additive metering unit, 3c-Mixing and stirring unit, 3d-Foaming unit, 3e-Molding unit, 3f-Curing unit, 3g-Demolding unit, 3h-Cutting unit, 3i-Packaging unit. Detailed Implementation

[0018] The features and advantages of the present invention will become clearer and more apparent from the following detailed description.

[0019] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0020] This invention proposes a process that can simultaneously treat industrial waste plastics and municipal sludge, achieving comprehensive treatment of these two types of solid waste and realizing the good effect of "treating waste with waste".

[0021] like Figure 1 This invention discloses a method for the co-treatment of industrial waste plastics and municipal sludge, comprising a waste plastic pyrolysis unit 1, a sludge-to-ceramsite production unit 2, and a brick-making unit 3. The waste plastic pyrolysis unit 1 includes a screening and crushing unit 1a, a drying and magnetic separation unit 1b, a pyrolysis reactor 1c, a gas-solid separation unit 1e, a solid heat carrier furnace unit 1d, a pyrolysis gas purification unit 1f, an oil-water separation unit 1g, an oil storage tank unit 1h, and a wastewater treatment unit 1i. The sludge-to-ceramsite production unit 2 includes a pretreatment unit 2a. The unit includes a proportioning and metering unit 2b, a primary mixing unit 2c, an aging unit 2d, a secondary mixing unit 2e, a granulation and screening unit 2f, a rotary calcining reactor 2g, a supplementary fuel unit 2h, a flue gas purification unit 2i, a cooling and screening unit 2j, and a brick making unit 3 including a ceramsite storage and conveying unit 3a, an additive metering unit 3b, a mixing and stirring unit 3c, a foaming unit 3d, a molding unit 3e, a curing unit 3f, a demolding unit 3g, a cutting unit 3h, and a stacking unit 3i.

[0022] The waste plastic treatment is completed by the waste plastic pyrolysis unit 1. The waste plastic raw materials from the waste plastic stockpile enter the screening and crushing unit 1a. The outlet of the screening and crushing unit 1a is connected to the inlet of the drying and magnetic separation unit 1b. The dried material enters the pyrolysis reactor 1c. The material undergoes a pyrolysis reaction in the pyrolysis reactor 1c. The pyrolysis carbon produced by pyrolysis and the heat carrier that provides the heat source for the pyrolysis reaction are transported to the solid heat carrier furnace 1d. The outlet of the solid heat carrier furnace 1d is connected to the inlet of the gas-solid separator 1e. The solid phase separated by the gas-solid separator 1e is returned to the pyrolysis reactor 1c. The high-temperature pyrolysis oil and gas generated by the pyrolysis reaction go to the pyrolysis gas purification unit 1f. The outlet of the pyrolysis gas purification unit 1f is connected to the oil-water separation unit 1g. The oil phase separated from the oil and water enters the oil storage tank 1h. The remaining wastewater enters the sewage treatment unit 1i for treatment and is discharged after meeting the standards. In this process, municipal sludge is first processed into ceramsite through a sludge-to-ceramsite unit 2. The municipal sludge and construction waste are then fed into a pretreatment unit 2a. The outlet of pretreatment unit 2a is connected to the inlet of a proportioning and metering unit 2b. The outlet of proportioning and metering unit 2b is connected to the inlet of a primary mixing unit 2c. The outlet of primary mixing unit 2c is connected to the inlet of an aging unit 2d. The outlet of aging unit 2d is connected to the inlet of a secondary mixing unit 2e. The material from the secondary mixing unit 2e enters a granulation and screening unit 2f. Unqualified granulated material is returned to the secondary mixing unit 2e for further processing. The outlet of granulation and screening unit 2f is connected to the inlet of a rotary roasting reactor 2g. The heat source for the rotary roasting reactor 2g is... The material originates from two parts: high-temperature flue gas from gas-solid separation unit 1e and supplementary fuel from supplementary fuel unit 2h. The high-temperature material enters the cooling and screening unit 2j through the outlet of the rotary roasting reactor 2g. The flue gas generated during the roasting process enters the flue gas purification unit 2i for purification and is then discharged in compliance with standards. The ceramsite from the cooling and screening unit 2j enters the brick making unit 3. The ceramsite is then sent to the mixing and stirring unit 3c along with the additives from the additive metering unit 3b via the ceramsite storage and conveying unit 3a. After that, it passes through the preparation unit 3d, the molding unit 3e, the curing unit 3f, the demolding unit 3g, the cutting unit 3h, and the stacking unit 3i in sequence to produce brick blocks for sale.

[0023] Example: like Figure 1 As shown: This invention comprises three main processing unit modules: a waste plastic pyrolysis unit 1, a sludge-to-ceramsite production unit 2, and a brick-making unit 3. These modules respectively realize the functions of waste plastic treatment, municipal sludge-to-ceramsite production, and ceramsite-to-brick production. The specific implementation method includes the following steps: S1: Waste plastic raw materials from the waste plastic stockpile are transported to screening and crushing unit 1a. The raw material has a moisture content of 20-40% and contains 1-5% non-organic components such as metals. After screening and crushing, the particle size of the raw material is less than 80mm. The outlet of screening and crushing unit 1a is connected to the inlet of drying and magnetic separation unit 1b. Drying and magnetic separation unit 1b can dry the material moisture content to less than 30% and the metal removal rate can reach more than 95%. The recovered metal products are recycled. After screening, crushing and drying and magnetic separation, the stability and high quality of the feed material indicators are guaranteed. S2: The material from the drying magnetic separation unit 1b is continuously and uniformly conveyed to the inlet of the pyrolysis reactor 1c, which is in a completely closed and oxygen-free state. The material undergoes a pyrolysis reaction in the pyrolysis reactor 1c. The reaction time can be adjusted according to the process conditions, and the reaction temperature range is 400~600℃, generating high-temperature pyrolysis oil and gas and pyrolysis char. The heat source for the reaction comes from the high-temperature heat carrier in the solid heat carrier furnace 1d, with a heat carrier temperature of 800~900℃. The solid heat carrier and the material are fully mechanically mixed in the reactor to ensure sufficient heat transfer between the material and the heat carrier and to prevent coking. S3: High-temperature pyrolysis oil and gas enter the pyrolysis gas purification unit 1f for cooling and purification. The dust content of the purified oil and gas is controlled below 2mg / Nm3. The outlet temperature range of the pyrolysis gas purification unit 1f is 50~100℃. The purified oil and gas contains only trace amounts of hydrogen chloride gas. The cooled liquid phase is discharged as fuel oil and sold externally. The oil production rate is 50~80%. The purified organic gas is sent as supplementary fuel to the solid heat carrier furnace 1d for combustion. S4: The pyrolytic carbon produced by the pyrolysis reaction and the heat carrier participating in the pyrolysis reaction are transported to the solid heat carrier furnace 1d. The pyrolytic carbon has a certain calorific value and provides heat by burning in the furnace. The high-temperature flue gas carries the heat carrier to the gas-solid separator unit 1e. The separated solid phase returns to the pyrolysis reactor 1c to participate in the pyrolysis reaction, realizing the circulation of the heat carrier. The temperature of the heat carrier is 800~900℃. The high-temperature flue gas after gas-solid separation enters the rotary roasting reactor 2g as the roasting heat source for sludge to produce ceramsite. S5: Sludge-to-ceramsite unit 2 can burn municipal sludge into harmless building ceramsite. The main raw materials are construction waste and municipal sludge. First, there is a pretreatment unit 2a for construction waste and municipal sludge. Construction waste (clay) is transported by truck to a warehouse for storage, where it undergoes natural drying to evaporate some moisture. Construction waste is then collected by a loader or grab bucket and fed to a descraper via a box feeder to remove stones, bricks, and other impurities. It then enters a roller crusher for further crushing. The crushed material is dried in a dryer and temporarily stored in a buffer silo. Municipal sludge from the factory is stored in a sludge pond. Since the sludge contains a large amount of moisture, leakage and moisture loss must be considered during the construction of the storage yard, ensuring proper surface protection and sealing. The odorous gases emitted by municipal sludge are mainly ammonia and hydrogen sulfide. To prevent odor emissions, it needs to be stored in a sealed workshop using negative pressure collection, which is then used as combustion air for the rotary roasting reactor. S6: Sludge from pretreatment unit 2a is fed into a silo using a grab crane, with a screw feeder underneath and a weighing scale controlling the feed rate. Construction waste is fed using a belt scale. Sludge and construction waste are transported separately to primary mixing unit 2c for mixing according to a specific ratio. Mixing is done using a twin-shaft mixer. The outlet of primary mixing unit 2c is connected to the inlet of aging unit 2d. The sludge undergoes aging treatment in aging unit 2d for approximately 7-15 days. The specific aging time will be determined through preliminary experiments based on the material's moisture content and properties to find the optimal aging parameters. The aged material then enters secondary mixing unit 2e for secondary mixing. After mixing, the material enters granulation and screening unit 2f for granulation. The moisture content of the granulator entering the granulator is <25%. The resulting ceramsite pellets are shaped and screened. Unqualified material is screened off and returned to secondary mixing unit 2e for re-mixing and granulation. Qualified ceramsite pellets are sent to a rotary calcining reactor. S7: The ceramsite from the granulation and screening unit 2f enters the rotary kiln through the feed pipe at the top of the kiln tail flue. The upper end of the feed pipe is equipped with a double gate valve to seal the material and ensure that there is no gas leakage when the material enters the kiln tail. The calcination heat source is the high-temperature flue gas generated by the pyrolysis of waste plastics and the supplementary fuel unit 2h. The supplementary fuel can be one or more of natural gas, biomass fuel, and coal. The calcination temperature is 1050~1250℃. As the rotary kiln rotates, the ceramsite gradually moves towards the kiln head. The high-temperature gas flows from the kiln head to the kiln tail, opposite to the direction of the material ball movement. During the movement, the ceramsite exchanges heat with the high-temperature flue gas (conduction, convection, radiation), and the temperature gradually increases. After passing through four temperature zones of drying, preheating, firing, and cooling, internal physicochemical changes occur, completing oxidation-reduction, dehydration, and carbonate decomposition. The generated gas causes the spheres to expand rapidly and be enveloped by the liquid phase that appears on the surface at high temperature, forming internal closed pores, and finally forming ceramsite. S8: 2g of high-temperature ceramsite from the rotary calcining reactor enters the single-cylinder cooler. Under the negative pressure at the kiln head of the rotary reactor, cold air is introduced from the discharge end of the cooler, and the ceramsite is cooled and discharged. The cold air is heated during the heat exchange process and enters the rotary kiln as high-temperature combustion air, which plays an energy-saving role. A screen is installed at the head of the single-cylinder cooler to separate ceramsite of different sizes and send them to different ceramsite bins for storage. The high-temperature flue gas at the kiln tail enters the flue gas purification unit 2i, and is discharged after purification treatment to meet the standards. S9: The ceramsite from the ceramsite storage and conveying unit 3a and the additives from the additive metering unit 3b are sent to the mixing and stirring unit 3c for thorough mixing. The additives include, but are not limited to, the following materials: silicate cementitious agent, fly ash, stone powder, sand, and tailings slag powder. S10: The material from the mixing unit 3c passes through the foaming unit 3d, the molding unit 3e, the curing unit 3f and the demolding unit 3g in sequence. The curing time can be set to 6~12h and the curing temperature is 20-60℃. After curing, the bricks are cut by the cutting unit 3h and stacking unit 3i to obtain finished masonry blocks.

[0024] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

[0025] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A system for co-processing of industrial waste plastics and municipal sludge, characterized in that, The application relates to a waste plastic pyrolysis unit (1), a sludge ceramic pellet unit (2) and a brick making unit (3). The waste plastic pyrolysis unit (1) receives waste plastic raw materials, generates pyrolysis carbon, waste oil, waste water and high-temperature flue gas after pyrolysis treatment of the waste plastic raw materials, wherein the pyrolysis carbon is used for energy supply for the pyrolysis reaction of the waste plastic raw materials, the waste oil is collected by an oil storage tank, and the waste water is discharged after treatment. The sludge ceramic pellet unit (2) uses the high-temperature flue gas generated in the pyrolysis reaction of the waste plastic raw materials as a heat source to calcine material balls to obtain ceramic pellets; the material balls are made of municipal sludge and construction waste soil. The brick making unit (3) uses the ceramic pellets obtained by the sludge ceramic pellet unit (2) to make bricks. The waste plastic pyrolysis unit (1) comprises a screening and crushing unit (1a), a drying and magnetic separation unit (1b), a pyrolysis reactor (1c), a gas-solid separation unit (1e), a solid heat carrier furnace (1d), a pyrolysis gas purification unit (1f), an oil-water separation unit (1g), an oil storage tank (1h) and a sewage treatment unit (1i).

2. The system for co-processing of industrial waste plastics and municipal sludge as claimed in claim 1, wherein, The screening and crushing unit (1a) receives waste plastic raw materials and screens and crushes the waste plastic raw materials. The screened and crushed raw materials enter the drying and magnetic separation unit (1b), which dries and removes metal from the screened and crushed raw materials. The obtained materials after drying and metal removal enter the pyrolysis reactor (1c), and the materials undergo pyrolysis reaction in the pyrolysis reactor (1c) to generate pyrolysis carbon and high-temperature pyrolysis oil gas; the reaction heat source of the pyrolysis reaction comes from the solid heat carrier of the solid heat carrier furnace (1d); the solid heat carrier in the pyrolysis reactor (1c) is fully mechanically mixed with the materials. The high-temperature pyrolysis oil gas enters the pyrolysis gas purification unit (1f) for oil gas cooling and purification; the obtained gas is used as a supplementary fuel and is sent into the solid heat carrier furnace (1d); the obtained liquid phase enters the oil-water separation unit (1g) for oil-water separation; the obtained oil phase is stored in the oil storage tank (1h); and the obtained waste water enters the sewage treatment unit (1i) for treatment and is discharged after reaching the standard. The pyrolysis carbon and the solid heat carrier participating in the pyrolysis reaction are transported to the solid heat carrier furnace (1d), burned in the furnace to provide heat, and generate high-temperature flue gas; the high-temperature flue gas carries the solid heat carrier to the gas-solid separation unit (1e), which separates the high-temperature flue gas carrying the solid heat carrier; the obtained solid phase returns to the pyrolysis reactor (1c) to participate in the pyrolysis reaction; and the obtained gas enters the sludge ceramic pellet unit (2) as a calcination heat source for the sludge ceramic pellet. The sludge ceramic pellet unit (2) comprises a pretreatment unit (2a), a proportioning and metering unit (2b), a primary mixing unit (2c), an aging unit (2d), a secondary mixing unit (2e), a granulation and screening unit (2f), a rotary calcination reactor (2g), a supplementary fuel unit (2h), a flue gas purification unit (2i) and a cooling and screening unit (2j).

3. The system for co-processing of industrial waste plastics and municipal sludge as claimed in claim 1, wherein, The pretreatment unit (2a) receives municipal sludge and construction waste soil, and makes the municipal sludge and the construction waste soil naturally dry and evaporate part of the water. ​ The municipal sludge and construction waste soil from the pretreatment unit (2a) are output to the primary mixing unit (2c) for primary mixing, and the proportioning metering unit (2b) is used to control the proportioning of the municipal sludge and construction waste soil; The material from the primary mixing unit (2c) enters the aging unit (2d) for aging; The material from the aging unit (2d) enters the secondary mixing unit (2e) for secondary mixing; The material from the secondary mixing unit (2e) enters the granulation and screening unit (2f) for granulation, and the granulation and screening unit (2f) screens the obtained material balls, and the qualified material balls are sent to the rotary calcination reactor (2g), and the unqualified material balls are returned to the secondary mixing unit (2e); The material balls are calcined in the rotary calcination reactor (2g) to obtain ceramsite; the calcination heat source of the rotary calcination reactor (2g) comes from the high-temperature flue gas generated by the pyrolysis reaction of the waste plastic raw material in the waste plastic pyrolysis unit (1) and the supplementary fuel unit (2h); The ceramsite from the rotary calcination reactor (2g) enters the cooling and screening unit (2j), under the negative pressure action of the rotary calcination reactor (2g), cold air is introduced from the discharge end of the cooling and screening unit (2j), and the ceramsite is discharged after being cooled; the cold air is heated in the heat exchange process and enters the rotary calcination reactor (2g) as high-temperature combustion-supporting air; the cooling and screening unit (2j) screens the cooled and discharged ceramsite according to the particle size and sends it to different ceramsite warehouses in the brick making unit (3) for storage; The high-temperature flue gas from the rotary calcination reactor (2g) enters the flue gas purification unit 2i, and is treated to meet the emission standard.

4. The system for co-processing of industrial waste plastics and municipal sludge as claimed in claim 1, wherein, The brick making unit (3) comprises a ceramsite storage and conveying unit (3a), an additive metering unit (3b), a mixing and stirring unit (3c), a foaming unit (3d), a mold injection unit (3e), a curing unit (3f), a demolding unit (3g), a cutting unit (3h) and a stacking unit (3i); The ceramsite storage and conveying unit (3a) is used to store ceramsite of different particle sizes, and the ceramsite from the ceramsite storage and conveying unit (3a) and the additive from the additive metering unit (3b) are sent to the mixing and stirring unit (3c) for sufficient mixing; The material from the mixing and stirring unit (3c) successively passes through the foaming unit (3d), the mold injection unit (3e), the curing unit (3f), the demolding unit (3g), the cutting unit (3h) and the stacking unit (3i) to obtain finished block bricks; wherein the foaming unit (3d), the mold injection unit (3e), the curing unit (3f), the demolding unit (3g), the cutting unit (3h) and the stacking unit (3i) are respectively used for foaming, mold injection, curing, demolding, cutting and stacking of the material.

5. The system for co-processing of industrial waste plastics and municipal sludge as claimed in claim 2, wherein, The waste plastic raw material is screened and crushed by the screening and crushing unit (1a), and the particle size of the raw material is less than 80 mm; The material obtained after drying and metal removal of the screened and crushed raw material has a water content of less than 30% and a metal removal rate of more than 95%.

6. The system for co-processing of industrial waste plastics and municipal sludge as claimed in claim 2, wherein, The pyrolysis reaction temperature ranges from 400 to 600℃; The temperature of the solid heat carrier of the solid heat carrier furnace (1d) is 800-900℃; When the high-temperature pyrolysis oil gas enters the pyrolysis gas purification unit (1f) for oil gas cooling and purification, the dust content of the purified oil gas is 2 mg / Nm 3 Hereinafter, the outlet temperature range of the pyrolysis gas purification unit (1f) is 50-100℃.

7. The system for co-processing of industrial waste plastics and municipal sludge as claimed in claim 3, wherein, The construction waste is taken by a forklift or a grab bucket, fed to a stone removing machine through a box feeder, and the impurities of the construction waste are removed, and then the construction waste is fed into a roll crusher for crushing treatment; the crushed material is dried in a dryer and temporarily stored in a buffer bin; The municipal sludge is stored in a sludge pool, and the foul gas emitted by the municipal sludge is collected by negative pressure and used as combustion-supporting gas of the rotary calcination reactor.

8. The system for co-processing of industrial waste plastics and municipal sludge as claimed in claim 3, wherein, The supplemental fuel in the supplemental fuel unit (2h) can be one or more of natural gas, biomass fuel or coal; The calcination temperature of the rotary calcination reactor (2g) is 1050-1250 DEG C, the material ball rotates in the rotary calcination reactor (2g) with the rotary kiln, and gradually moves to the kiln head, the high-temperature flue gas generated by pyrolysis of the waste plastic raw material or the high-temperature flue gas generated by combustion of the supplemental fuel flows from the kiln head to the kiln tail, which is opposite to the movement direction of the material ball, and the ceramic ball exchanges heat with the high-temperature flue gas during the movement, and finally forms the ceramic ball.

9. The system for co-processing of industrial waste plastics and municipal sludge as claimed in claim 4, wherein, The additive includes one or more of silicate cementing agent, fly ash, stone powder, sand or tailing powder; The curing time of the curing unit (3f) is 6-12 h, and the curing temperature is 20-60 DEG C.

10. A method for co-processing of industrial waste plastics and municipal sludge, characterized in that, The system for co-processing industrial waste plastics and municipal sludge is realized by using the system for co-processing industrial waste plastics and municipal sludge according to any one of claims 1-9, comprising: The waste plastic pyrolysis unit (1) receives waste plastic raw material, and generates pyrolysis carbon, waste oil, waste water and high-temperature flue gas after pyrolysis treatment, wherein the pyrolysis carbon is used to provide energy for the pyrolysis reaction of the waste plastic raw material, the waste oil is collected by an oil tank, and the waste water is discharged after treatment; The sludge ceramic ball unit (2) uses the high-temperature flue gas generated by the pyrolysis reaction of the waste plastic raw material as a heat source to calcine the material ball, and obtains ceramic ball; the raw material of the material ball is municipal sludge and construction waste; The brick making unit (3) uses the ceramic ball obtained by the sludge ceramic ball unit (2) to make bricks.

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