Internal combustion type ceramsite production equipment

Abstract

The utility model relates to internal combustion type ceramsite production equipment, and belongs to the technical field of solid waste resource utilization. The equipment comprises a sub-bin type raw material pretreatment system, a multi-stage grinding and mixing device, a granulating and forming device, a rotary calcining kiln body and a waste heat recovery device, wherein the raw material pretreatment system adopts four industrial solid wastes of coal gangue, shale, red mud and coal slime for sub-bin storage; the multi-stage grinding and mixing device comprises a multi-stage grinding cavity and an angle-adjustable stirring blade; the granulating and forming device comprises an extrusion granulator and a vibrating screen, and can be used for preparing granules with uniform particle sizes; and the calcining process is carried out in the rotary kiln to form a closed production system. According to the equipment, consumption of natural raw materials can be reduced, dependence on conventional raw materials such as clay and shale in traditional ceramsite production is broken through, resource utilization of multiple types of solid waste is achieved, the burden of solid waste treatment is relieved, no additional chemical additive is added, energy consumption is reduced through a waste heat circulation system, and the equipment is suitable for production of multiple types of industrial solid waste.

Description

Technical Field

[0001] This utility model relates to an internal combustion type ceramsite production equipment, belonging to the field of ceramsite processing technology. Background Technology

[0002] Large-scale stockpiling of solid waste pollutes and harms the atmosphere, soil, water bodies, and biosphere. Expanded clay aggregate (ECA) is a lightweight aggregate with advantages such as low density, high strength, and good thermal insulation. Traditional ECA processes use non-renewable resources like shale and clay as main raw materials, consuming natural resources, and the high price of clay minerals leads to excessively high production costs. Some solid wastes have a high compatibility with ECA raw materials, making them excellent matrix materials. Using solid waste to produce ECA products allows for large-scale solid waste consumption and recycling, resulting in significant environmental and economic benefits. However, large-scale promotion of ECA technology from industrial solid waste still faces many challenges in the processing of ECA. Chinese patent application CN104030719A discloses a method for producing ceramsite from sludge. The raw materials include sludge, coal gangue, clay, and red mud. The raw materials are then processed by mixing, extruding into pellets, drying, preheating, and calcining. This patent utilizes solid waste sludge to produce ceramsite, but it requires the addition of chemical additives such as glass powder during processing. It relies on the use of additives, and the calcination process is relatively complex, resulting in significant heat loss.

[0003] In this field, closed systems can reduce energy consumption. However, ceramsite production requires a significant amount of fuel, and conventional closed systems cannot address the issue of frequent external fuel and chemical additive supply. Integrating conventional fuel and chemical additive supply structures into a closed system would make the system excessively large, and effectively controlling the frequent fuel supply would also be a challenging problem. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of this utility model is to provide an internal combustion type ceramsite production equipment. The raw material section has only four chambers: coal gangue chamber, red mud chamber, coal slime chamber, and shale chamber. The combustion section adopts a rotary kiln partition to form a closed system. Through the internal combustion principle, the heat energy is fully utilized, greatly reducing energy consumption, while ensuring high-quality production of ceramsite.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An internal combustion type ceramsite production equipment is a closed system consisting of a compartmented raw material pretreatment system, a multi-stage grinding and mixing device, a granulation and forming device, a rotary calcining kiln, and a waste heat recovery device connected in sequence. The raw material pretreatment system comprises a coal gangue bin, a red mud bin, a coal slime bin, and a shale bin. The multi-stage grinding and mixing device mixes and grinds the pretreated raw materials. The granulation and forming device pulverizes the mixed and ground raw materials into granules. The internal combustion calcination process is performed in the rotary calcining kiln, and the waste heat recovery device recovers the waste heat from the internal combustion calcination process. The entire system constitutes a closed production system.

[0007] In one embodiment, since the initial coal gangue and shale raw materials generally have a large particle size, a crushing component is built into the coal gangue bin and shale bin to perform crushing pretreatment on the raw materials. The crushing component may be, for example, a crushing roller.

[0008] In one embodiment, because the initial red mud and coal slime raw materials have high moisture content, drying components are configured in the red mud and coal slime bins to perform pre-treatment drying on the raw materials. The drying components can be electrically or fuel-heated equipment, preferably controlling the moisture content to below 8%. Typically, waste heat recovered from subsequent internal combustion processes can be utilized to further improve thermal efficiency. That is, in this case, the heat source equipment of the drying components is connected to the waste heat recovery device, where the heat source equipment can be, for example, a conventional heat exchanger.

[0009] In one embodiment, the four types of industrial solid waste—coal gangue, shale, red mud, and coal slime—are stored in separate bins, and the initial quantities for each bin can be pre-mixed. Furthermore, to achieve process control, weighing devices can be installed on the discharge pipelines of the coal gangue bin, red mud bin, coal slime bin, and shale bin. These weighing devices allow for online quantitative batching. For example, the weighing devices can be sensors integrated into the feeding belt or separate weighing bins on the feeding line.

[0010] In one embodiment, the multi-stage grinding and mixing device includes multi-stage grinding chambers, each equipped with different grinding components, to achieve better grinding effect and efficiency through multi-stage grinding.

[0011] In one embodiment, the multi-stage grinding chamber is two-stage, wherein the first-stage grinding chamber is equipped with stirring blades, and the second-stage grinding chamber is equipped with crushing rollers. Further, the first-stage grinding chamber is a horizontal chamber, in which case the shaft of the stirring blades is horizontally positioned, and the blades are mounted on the shaft, preferably with adjustable angles, to perform preliminary stirring and grinding of the material. The second-stage grinding chamber is a vertical chamber, its top end connected to the conveying end of the first-stage grinding chamber, achieving a good grinding effect through a stirring-then-crushing method.

[0012] In one embodiment, the granulation and forming device is used to obtain ceramsite with uniform particle size from ground raw materials, thereby improving calcination efficiency and finished product strength. Specifically, the upper surface of the granulation and forming device is fixedly connected to a feed inlet, which is connected to the discharge port of a multi-stage grinding and mixing device. The interior of the device houses an extrusion granulator and a vibrating screen. The extrusion granulator includes two extrusion cylinders arranged side-by-side directly below the feed inlet, which extrude and crush the raw materials to obtain the desired particles. Preferably, it can extrude raw material powder into particles with a particle size of 3-8 mm. The vibrating screen is arranged obliquely and located directly below the extrusion granulator, used to control particle uniformity through sieving. Different mesh sizes of screens can be used in engineering depending on the particle size requirements. Obviously, the extrusion cylinders are connected to a geared motor to drive the rotation of the cylinders.

[0013] In one embodiment, the inner wall of the rotary calcining kiln is provided with a honeycomb ceramic insulation layer with a thickness of 10-15mm, which is mainly used for kiln insulation and improving thermal efficiency.

[0014] In one embodiment, the rotary calcining kiln body is divided into a preheating section, an internal combustion section, and a cooling section according to the material conveying direction, with each section having independent temperature control; wherein the temperature of the preheating section is 200-400℃, the temperature of the internal combustion section is 900℃-1200℃, and the cooling section is connected to an air-cooling device; the present invention features a segmented temperature control design for the cylinder body and can be equipped with a gradient insulation layer, for example, between adjacent sections, materials such as honeycomb ceramics or mullite bricks can be used for insulation to achieve differences in thermal resistance between different sections.

[0015] In one embodiment, the length of the preheating section is designed such that, in conjunction with the conveying speed, the material residence time is 15–20 minutes; the length of the internal combustion section is designed such that, in conjunction with the conveying speed, the material residence time is 30–40 minutes.

[0016] In one embodiment, the cooling section is equipped with an air-cooling device, using direct air cooling to reduce the kiln outlet temperature to below 100°C, thus preventing thermal stress-induced cracking. High-temperature exhaust gas is recovered by a waste heat recovery device to preheat combustion air or generate steam, thereby reducing energy consumption.

[0017] The coal slime used in this invention has a typical calorific value of not less than 1800 kJ / kg, enabling self-sustaining combustion during the calcination stage without the need for external fuel. By utilizing the calorific value characteristics of coal slime to replace traditional fuels, energy consumption is further reduced.

[0018] In summary, this utility model possesses numerous advantages and practical value, achieving efficient utilization of solid waste resources. Its raw material scheme primarily utilizes coal gangue and red mud, significantly reducing raw material costs while simultaneously disposing of solid waste and solving the problem of solid waste accumulation. The adoption of a closed system enables self-sustaining combustion of solid waste, reducing process energy consumption by 30%–40%. The addition of a waste heat recovery module to the traditional rotary kiln further enhances resource utilization. Both its structure and function represent significant improvements, demonstrating substantial technological advancement and excellent practical value. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the main structure of this utility model;

[0020] Figure 2 This is a schematic diagram of a multi-stage grinding and mixing device;

[0021] Figure 3 This is a schematic diagram of the granulation and molding device.

[0022] In the diagram: 1. Compartmentalized raw material pretreatment system; 2. Multi-stage grinding and mixing device; 3. Granulation and forming device; 4. Rotary calcining kiln; 5. Waste heat recovery device; 1a. Coal gangue bin; 1b. Red mud bin; 1c. Coal slime bin; 1d. Shale bin; 2a. Primary grinding chamber; 2b. Secondary grinding chamber; 2c. Crushing roller; 2d. Agitator blade; 3a. Feed inlet; 3b. Extrusion granulator; 3c. Vibrating screen. Detailed Implementation

[0023] The following is in conjunction with the appendix Figure 1 The embodiments of this utility model are described in detail.

[0024] Example 1

[0025] like Figure 1 , Figure 2 and Figure 3 This utility model discloses an internal combustion type ceramsite production equipment, a closed system, which consists of a compartmentalized raw material pretreatment system 1, a multi-stage grinding and mixing device 2, a granulation and forming device 3, a rotary calcining kiln body 4, and a waste heat recovery device 5 connected in sequence. The raw material pretreatment system 1 consists only of a coal gangue bin 1a, a red mud bin 1b, a coal slime bin 1c, and a shale bin 1d. The inlet of the multi-stage grinding and mixing device 2 is connected to the outlet of the raw material pretreatment system 1, the inlet of the granulation and forming device 3 is connected to the outlet of the multi-stage grinding and mixing device 2, the inlet of the rotary calcining kiln body 4 is connected to the outlet of the granulation and forming device 3, and the waste heat recovery device 5 is connected to the rotary calcining kiln body 4 to recover waste heat from the calcination process.

[0026] In the raw material pretreatment system 1, the coal gangue bin 1a and shale bin 1d mainly use crushing components to pre-treat the coal gangue and shale inside, while the red mud bin 1b and coal slime bin 1c mainly use drying components to pre-treat the red mud and coal slime inside. That is, the coal gangue and shale are crushed into fine materials, the red mud and coal slime are dried to obtain powder, the crushed coal gangue and shale are mixed with the dried red mud and coal slime to obtain an initial mixture, and the initial mixture is ground and mixed in a multi-stage grinding and mixing device 2 to obtain raw material powder.

[0027] The multi-stage grinding and mixing device 2 in this embodiment adopts a two-stage grinding device. The first-stage grinding chamber 2a is equipped with stirring blades 2d for preliminary stirring and grinding, and the second-stage grinding chamber 2b is equipped with crushing rollers 2c for fine crushing and grinding, finally obtaining a mixed raw material powder with a product particle size range of 3-8mm.

[0028] In this embodiment, the feed inlet 3a of the granulation and molding device 3 is connected to the discharge outlet of the multi-stage grinding and mixing device 2. Inside the device, there is an extrusion granulator 3b and a vibrating screen 3c. The extrusion granulator 3b includes two extrusion cylinders arranged horizontally side by side directly below the feed inlet 3a. The vibrating screen 3c is arranged obliquely and located directly below the extrusion granulator 3b. The extruded ceramsite is vibrated and screened to obtain ceramsite with uniform particle size.

[0029] In this embodiment, the rotary calcining kiln body 4 is internally divided into a preheating section, an internal combustion section, and a cooling section according to the material conveying direction, with each section having independent temperature control. The temperature of the preheating section is 200–400°C, the temperature of the internal combustion section is 900°C–1200°C, and the cooling section is connected to an air-cooling device. The length of the preheating section is designed to allow the material residence time to be 15–20 minutes in conjunction with the conveying speed; the length of the internal combustion section is designed to allow the material residence time to be 30–40 minutes in conjunction with the conveying speed.

[0030] Furthermore, the entire rotary kiln body 4 can be divided into a preheating section, an internal combustion section, and a cooling section according to time using temperature control and timing equipment.

[0031] The method of use and principle of this utility model are as follows:

[0032] Using four types of industrial solid waste—coal gangue, shale, red mud, and coal slime—as raw materials, the raw materials undergo crushing and screening pretreatment in a raw material pretreatment system 1. The pretreated raw materials are then premixed according to a preset ratio of 50%–60% coal gangue, 8%–15% shale, 16%–22% red mud, and 5%–15% coal slime before being fed into a multi-stage grinding and mixing device 2. Alternatively, the raw materials can be fed separately into the multi-stage grinding and mixing device 2 before premixing. In the multi-stage grinding and mixing device, the raw materials are ultrafine ground to obtain raw material powder, which is then extruded and granulated in a granulation and forming device 3. The powder is then demolded and pelletized, and then subjected to gradient calcination in a rotary calcining kiln 4. During the calcination stage, the calcination process utilizes the calorific value of the coal slime for self-sustaining combustion, requiring no fuel, ultimately yielding ceramsite. This invention reduces equipment investment, energy consumption, and raw material processing costs, breaking through the traditional dependence on clay resources in ceramsite production. It establishes a "waste-to-waste" circular economy model, possessing significant environmental benefits and industrial application value.

[0033] In this invention, coal gangue and red mud are typical process wastes with high traditional treatment costs (approximately 30-50 yuan / ton), and are used as the main raw materials; shale is mainly used as a binder to enhance the shaping of the raw materials; coal slime is mainly used as fuel, with a calorific value of ≥1800kJ / kg.

[0034] The raw material content parameter range of this utility model is set based on three principles: solid waste resource utilization, process adaptability, and cost-performance control. Through experimental optimization and verification, the optimal balance between the performance and cost of ceramsite is achieved. Specifically, coal gangue accounts for the largest proportion, mainly because it provides structural support and expansion; shale is the most binding, and a certain amount may be needed to ensure molding, but too much will affect sintering efficiency; red mud contains metal oxides that can enhance strength, but excessive amounts will affect porosity; coal slime, as fuel, can sustain combustion if its calorific value is sufficient, so a sufficient proportion is needed to provide heat, but too much will lead to excessively rapid combustion and excessive residue.

[0035] This invention controls the moisture content and particle size of raw materials during the pretreatment stage, ensuring the uniformity of the raw materials and improving calcination efficiency. The purpose of crushing is to further improve the uniformity of the materials. The purpose of drying is to remove moisture from the raw materials, avoiding cracking or deformation caused by rapid evaporation of moisture during subsequent high-temperature calcination, and also reducing energy consumption during calcination. The purpose of homogenization is to prevent agglomeration from affecting the reaction progress. The purpose of grinding is to increase the specific surface area and improve the reaction efficiency of the raw material powder, which is helpful for product quality.

[0036] This invention employs a phased gradient calcination method in the rotary calcining kiln body 4, and recovers high-temperature waste gas for preheating combustion air or generating steam, which can generally reduce energy consumption by 30%.

[0037] The present invention provides the following specific embodiments:

[0038]

[0039]

[0040] The raw materials of the components in the above embodiments are granulated, dried, and then calcined in a rotary kiln under the following combustion conditions:

[0041]

[0042] The ceramsite obtained in the above embodiments all meet the quality standards. The mechanical properties (cylindrical compressive strength ≥ 4 MPa, compressive strength ≥ 20 MPa) and physical properties (water absorption ≤ 15%, bulk density ≤ 900 kg / m³) of various types of ceramsite are satisfactory. 3 All meet or exceed national standards and are suitable for use in building materials, water treatment filter media, and oil well proppant applications.

[0043] The above examples are not exhaustive examples of the best possible embodiment of the utility model. The device of this utility model can also take many other forms.

[0044] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the utility model in any way. Although the present utility model has been disclosed above with preferred embodiments, it is not intended to limit the present utility model. Any person skilled in the art can make any modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model's technical solution. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model's technical solution shall still fall within the scope of the present utility model's technical solution.

Claims

1. An internal combustion type ceramsite production equipment, characterized in that, The application relates to a closed system which is sequentially connected by a bin-type raw material pretreatment system (1), a multi-stage grinding and mixing device (2), a granulating and forming device (3), a rotary calcining kiln body (4) and a waste heat recovery device (5); wherein the raw material pretreatment system (1) is composed of a coal gangue bin (1a), a red mud bin (1b), a coal slime bin (1c) and a shale bin (1d); the multi-stage grinding and mixing device (2) mixes and grinds the pretreated raw materials; the granulating and forming device (3) makes the mixed and ground raw material powder into particles; the rotary calcining kiln body (4) performs an internal combustion calcining process, and the waste heat recovery device (5) recovers the waste heat of the internal combustion calcining process.

2. The apparatus for producing a ceramic product according to claim 1, wherein The coal gangue bin (1a) and the shale bin (1d) are internally provided with crushing assemblies for crushing and pretreating the internal raw materials; the red mud bin (1b) and the coal slime bin (1c) are provided with drying assemblies for drying and pretreating the internal raw materials.

3. The apparatus according to claim 2, wherein The heat source equipment of the drying assembly is connected with the waste heat recovery device (5).

4. The apparatus for producing a ceramic fuel according to claim 1, wherein The coal gangue bin (1a), the red mud bin (1b), the coal slime bin (1c) and the shale bin (1d) are all provided with weighing equipment on the discharge pipelines.

5. The apparatus for producing a ceramic fuel according to claim 1, wherein The multi-stage grinding and mixing device (2) comprises multi-stage grinding cavities, and each stage of the grinding cavities is provided with different grinding assemblies.

6. The apparatus according to claim 5, wherein The multi-stage grinding cavities are two-stage, wherein the first-stage grinding cavity (2a) is provided with stirring paddles (2d), and the second-stage grinding cavity (2b) is provided with crushing rollers (2c).

7. The apparatus according to claim 6, wherein The first-stage grinding cavity (2a) is a horizontal cavity, and the second-stage grinding cavity (2b) is a vertical cavity, and the top end of the second-stage grinding cavity (2b) is connected with the conveying end of the first-stage grinding cavity (2a).

8. The apparatus according to claim 1, wherein The upper surface of the body of the granulating and forming device (3) is fixedly connected with a feeding port (3a), the feeding port (3a) is connected with the discharge port of the multi-stage grinding and mixing device (2), the inside of the body is provided with an extrusion granulator (3b) and a vibrating screen (3c), the extrusion granulator (3b) comprises two extrusion cylinders which are arranged side by side below the feeding port (3a), and the vibrating screen (3c) is arranged obliquely and below the extrusion granulator (3b).

9. The apparatus according to claim 1, wherein The rotary calcining kiln body (4) is divided into a preheating section, an internal combustion combustion section and a cooling section according to the material conveying direction, and each section is independently temperature-controlled; wherein the temperature of the preheating section is 200-400 DEG C, the temperature of the internal combustion combustion section is 900 DEG C-1200 DEG C, and the cooling section is connected with an air cooling device.

10. The apparatus according to claim 9, wherein The length of the preheating section is designed so that, in cooperation with the conveying speed, the material residence time can be 15-20 min; the length of the internal combustion combustion section is designed so that, in cooperation with the conveying speed, the material residence time can be 30-40 min.

Images