A waste disposal device

Abstract

The utility model discloses a kind of waste treatment devices, including the pretreatment unit, mixed crushing unit and circulating fluidized bed boiler connected in turn, the pretreatment unit includes sludge frame dewaterer, white mud dry base storage and sludge dry base storage, the mixed crushing unit includes mixing bin, coal belt, crusher unit and screening unit, the circulating fluidized bed boiler is equipped with hearth temperature sensor and ash outlet, the white mud dry base storage and sludge dry base storage inside are all provided with crushing mechanism, and spiral unloader is mounted in discharge port, utilize the mutual complementation of sludge and white mud's physicochemical property, sludge provides combustion calorific value to realize fuel replacement, white mud provides alkaline component to complete in-furnace desulfurization, reduce desulfurizer (magnesium oxide) dosage, solve the paper industry production solid waste treatment unit fragmentation problem, realize pollutant collaborative control and solid waste resource integration.

Description

Technical Field

[0001] This utility model belongs to the field of waste treatment technology in paper mills, and specifically relates to a waste treatment device. Background Technology

[0002] The paper industry generates approximately 65,000 tons of high-moisture sludge and 35,000 tons of alkali-recovered white mud annually. Under current technology, sludge, due to its high moisture content (typically >60%), low and fluctuating calorific value, requires large amounts of auxiliary fuel for incineration, resulting in high treatment costs. White mud, rich in alkaline components such as CaCO3 and Ca(OH)2, is subject to landfilling using traditional methods, consuming land resources and posing a risk of leachate pollution. Furthermore, in subsequent desulfurization processes, companies often employ wet desulfurization, which requires continuous addition of magnesium oxide, leading to significant annual operating costs.

[0003] Currently, sludge is mainly treated by incineration, but sludge incineration technology generally suffers from poor fuel compatibility and low thermal efficiency. White mud resource utilization technologies are mostly limited to the preparation of building material additives, failing to achieve synergistic control of pollutants. Desulfurization processes rely on the addition of external desulfurizing agents, failing to utilize the inherent alkaline properties of white mud. Although some studies have attempted co-treatment of sludge with calcium-based materials, these methods have not been optimized for the characteristics of papermaking white mud, resulting in coking, insufficient desulfurization efficiency, or poor ash stability.

[0004] Therefore, this utility model proposes a waste treatment device that achieves complementary physical and chemical properties between industrial solid waste sludge and white mud from the papermaking industry, simultaneously solving problems related to fuel substitution, desulfurization costs, and solid waste resource utilization, thus overcoming the bottlenecks of fragmented treatment units and high operating costs in existing technologies. Utility Model Content

[0005] To achieve the above objectives, this utility model provides the following technical solution: a waste treatment device, comprising a pretreatment unit, a mixing and crushing unit, and a circulating fluidized bed boiler connected in sequence. The pretreatment unit includes a sludge plate and frame dewatering machine, a white mud dry base storage silo, and a sludge dry base storage silo. The mixing and crushing unit includes a mixing silo, a coal conveyor belt, a crushing unit, and a screening unit. The circulating fluidized bed boiler is equipped with a furnace temperature sensor and an ash outlet.

[0006] As a preferred technical solution of this utility model, both the white mud dry base storage silo and the sludge dry base storage silo are equipped with a crushing mechanism inside, and both are equipped with a screw unloader at the discharge port.

[0007] As a preferred technical solution of this utility model, the discharge ends of the white mud dry base storage silo and the sludge dry base storage silo are connected to the feed end of the mixing silo via a belt conveyor.

[0008] As a preferred embodiment of the present invention, the mixing and crushing unit further includes a drying unit, which is located between the crushing unit and the screening unit.

[0009] In a preferred embodiment of this invention, the outlet of the screening unit is connected to the feed inlet of the crushing unit via a conveyor.

[0010] As a preferred technical solution of this utility model, the furnace temperature range of the circulating fluidized bed boiler is 850℃-950℃, and the furnace height is ≥15m.

[0011] As a preferred technical solution of this utility model, the ash outlet of the circulating fluidized bed boiler is connected to a building material forming equipment via a sealed conveyor belt, the building material forming equipment including a brick press or a cement mixing silo.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] (1) This utility model utilizes the complementary physical and chemical properties of sludge and white mud. Sludge provides combustion calorific value to achieve fuel substitution, while white mud provides alkaline components to complete in-furnace desulfurization, reducing the amount of desulfurizing agent (magnesium oxide), solving the problem of fragmented solid waste treatment units in paper production, and realizing the integrated control of pollutants and the resource utilization of solid waste.

[0014] (2) This utility model reduces the auxiliary fuel required for separate sludge incineration and the magnesium oxide addition for wet desulfurization, reduces the amount of coal used and the cost of desulfurizing agent, and saves the cost of solid waste landfill disposal, significantly reducing the annual operating cost of enterprises and breaking through the bottleneck of high operating costs of existing technologies.

[0015] (3) The resource utilization rate of incineration product ash residue is ≥90%, which can be directly used for building material production, avoiding the risks of land occupation and leachate pollution caused by solid waste landfill; sludge replaces fossil fuels to reduce carbon emissions, and in-furnace desulfurization reduces flue gas pollutant emissions, achieving a win-win situation for environmental protection and resource recycling.

[0016] (4) Optimize the treatment process for the characteristics of papermaking white mud. By controlling the two-stage crushing and drying and setting the parameters of the circulating fluidized bed boiler, problems such as coking, insufficient desulfurization efficiency and poor ash stability are avoided, the fuel adaptability and thermal efficiency are improved, and the stable and efficient operation of the equipment is ensured. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0018] Figure 1 This is a system connection diagram of the present invention;

[0019] In the picture:

[0020] 1. Pretreatment unit; 11. Sludge plate and frame dewatering machine; 12. White mud dry basis storage silo; 13. Sludge dry basis storage silo; 14. Crushing mechanism; 15. Screw unloader;

[0021] 2. Mixing and crushing unit; 21. Mixing bin; 22. Coal conveyor belt; 23. Crushing unit; 24. Screening unit; 25. Drying unit;

[0022] 3. Circulating fluidized bed boiler; 31. Furnace temperature sensor; 32. Ash and slag outlet;

[0023] 4. Building material forming equipment. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] Example

[0026] Please see Figure 1 The present invention provides the following technical solution: a waste treatment device, comprising a pretreatment unit 1, a mixing and crushing unit 2, and a circulating fluidized bed boiler 3 connected in sequence. The pretreatment unit 1 includes a sludge plate and frame dewatering machine 11, a white mud dry base storage silo 12, and a sludge dry base storage silo 13. The mixing and crushing unit 2 includes a mixing silo 21, a coal conveyor belt 22, a crushing unit 23, and a screening unit 24. The circulating fluidized bed boiler 3 is equipped with a furnace temperature sensor 31 and an ash outlet 32.

[0027] In order to ensure that the particle size of the white mud and sludge is initially uniform and that the material can be accurately discharged according to the preset ratio, in this embodiment, as a preferred technical solution of the present invention, both the white mud dry storage bin 12 and the sludge dry storage bin 13 are equipped with a crushing mechanism 14, and both are equipped with a screw unloader 15 at the discharge port.

[0028] In order to accurately transport the pretreated white mud and sludge to the mixing bin 21 and ensure the continuous and stable operation of the subsequent mixing process, in this embodiment, as a preferred technical solution of the present invention, the discharge ends of the white mud dry base storage bin 12 and the sludge dry base storage bin 13 are connected to the feed end of the mixing bin 21 by a belt conveyor.

[0029] In order to reduce the moisture content of the material to ≤15% and optimize the fuel characteristics to improve combustion efficiency, in this embodiment, as a preferred technical solution of the present invention, the mixing and crushing unit 2 further includes a drying unit 25, which is located between the crushing unit 23 and the screening unit 24.

[0030] In order to achieve closed-loop control of material particle size and ensure that the particle size of the material entering the furnace is ≤3mm to improve combustion completeness, in this embodiment, as a preferred technical solution of the present invention, the outlet of the screen material of the screening unit 24 is connected to the feed port of the crushing unit 23 through a conveyor.

[0031] In order to provide a suitable environment for the complete combustion of materials and the reaction between alkaline components in white mud and flue gas pollutants, ensure the residence time of combustion dust inside the furnace, avoid CaO sintering deactivation and ensure desulfurization efficiency, in this embodiment, as a preferred technical solution of the present invention, the furnace temperature range of the circulating fluidized bed boiler 3 is 850℃-950℃ and the furnace height is ≥15m.

[0032] In order to realize the resource utilization of combustion ash and avoid the risks of land occupation and secondary pollution caused by solid waste landfill, in this embodiment, as a preferred technical solution of the present invention, the ash outlet 32 ​​of the circulating fluidized bed boiler 3 is connected to the building material forming equipment 4 through a sealed conveyor belt. The building material forming equipment 4 includes a brick press or a cement mixing silo.

[0033] In summary, by utilizing the above-described technical solution of this utility model, collaborative processing is achieved through the following process:

[0034] Pretreatment stage: High moisture content sludge first enters the sludge plate and frame dewatering machine 11 in pretreatment unit 1, where moisture is removed by mechanical pressing (sludge moisture content ≤50%). The dewatered sludge is then transported to the sludge dry base storage silo 13. Papermaking white mud (rich in alkaline components such as CaCO3 and Ca(OH)2) is directly stored in the white mud dry base storage silo 12 in pretreatment unit 1. The crushing mechanism 14 in both storage silos breaks up and crushes the agglomerated materials. The screw unloader 15 at the discharge port of both storage silos quantitatively transports the sludge and white mud to the mixing silo 21 of the mixing and crushing unit 2 at a mass ratio of 1:0.5. Then, the coal blocks are transported to the mixing silo 21 via the coal conveyor belt 22, laying the foundation for subsequent synergistic reactions.

[0035] Mixing and Crushing Stage: The mixing and crushing unit 2 mixes the pretreated sludge, white mud and coal in the mixing chamber 21 using a crane grab bucket (or a mixing and crushing mechanism built into the mixing chamber 21, which is not limited here). The mixture is then conveyed to the crushing unit 23 for crushing. After crushing, the material enters the drying unit 25 (located between the crushing unit 23 and the screening unit 24) and is dried to a moisture content of ≤15%. It is then crushed by the screening unit 24 to a particle size of ≤3mm (the material on the screen of the screening unit 24 is returned to the crushing unit 23 by a conveyor to form a closed loop to ensure that the particle size meets the standard). This process solves the problem that sludge requires a lot of fuel due to its low calorific value and optimizes the fuel characteristics through crushing and drying.

[0036] Combustion and synergistic reaction stage: Qualified materials are fed into circulating fluidized bed boiler 3. The alkaline properties of white mud are used to achieve flue gas self-purification and the parameters of "furnace temperature 850℃-950℃, furnace height ≥15m" are set. The organic matter in the sludge is burned to release heat value (replacing part of the raw coal and reducing fuel consumption). CaCO3 and Ca(OH)2 in the white mud are calcined and decomposed into CaO at high temperature (CaCO3 + high temperature = CaO + CO2, Ca(OH)2 + high temperature = CaO + H2O).

[0037] CaO reacts with acidic pollutants such as SO2 in flue gas (CaO + SO2 + ½O2 → CaSO4) to achieve in-furnace desulfurization (reducing the addition of magnesium oxide as a desulfurizing agent in wet desulfurization and lowering operating costs).

[0038] The ash produced by combustion (including CaSO4, CaO, etc.) is sent to the building material forming equipment 4 (brick press or cement mixing silo) through ash outlet 32, and directly processed into building materials to realize resource utilization.

[0039] Finally, it should be noted that, in this utility model, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," "fixing," "screw connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0040] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A waste treatment device, comprising a pretreatment unit (1), a mixing and crushing unit (2), and a circulating fluidized bed boiler (3) connected in sequence, characterized in that: The pretreatment unit (1) includes a sludge plate and frame dewatering machine (11), a white mud dry base storage silo (12) and a sludge dry base storage silo (13). The mixing and crushing unit (2) includes a mixing silo (21), a coal conveyor belt (22), a crushing unit (23) and a screening unit (24). The circulating fluidized bed boiler (3) is equipped with a furnace temperature sensor (31) and an ash outlet (32).

2. The waste treatment device according to claim 1, characterized in that: Both the white mud dry base storage silo (12) and the sludge dry base storage silo (13) are equipped with a crushing mechanism (14), and both are equipped with a screw unloader (15) at the discharge port.

3. The waste treatment device according to claim 2, characterized in that: The discharge ends of the white mud dry base storage silo (12) and the sludge dry base storage silo (13) are connected to the feed end of the mixing silo (21) via belt conveyors.

4. The waste treatment device according to claim 1, characterized in that: The mixing and crushing unit (2) also includes a drying unit (25), which is located between the crushing unit (23) and the screening unit (24).

5. A waste treatment device according to claim 1, characterized in that: The oversize outlet of the screening unit (24) is connected to the feed inlet of the crushing unit (23) via a conveyor.

6. A waste treatment device according to claim 1, characterized in that: The furnace temperature range of the circulating fluidized bed boiler (3) is 850℃-950℃, and the furnace height is ≥15m.

7. A waste treatment device according to claim 6, characterized in that: The ash outlet (32) of the circulating fluidized bed boiler (3) is connected to the building material forming equipment (4) via a sealed conveyor belt. The building material forming equipment (4) includes a brick press or a cement mixing silo.

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