A kind of chamber type slag granulation device and process method

Abstract

The application discloses a kind of granulation devices and process methods of chamber type slag, specifically related to steel metallurgical solid waste processing field, including rotator, modular water-cooled grate, membrane water-cooled wall shell, material receiving station, unloading station and granulation medium cooling unit;Rotator is evenly separated into multiple independent granulation chambers along circumference inside, and metal ball or metal rod is built in chamber as granulation and heat exchange medium;Modular water-cooled grate is installed outside chamber, for controlling slag particle size;Membrane water-cooled wall shell seals and covers rotator and connects waste heat recovery system.The application realizes efficient heat exchange and controllable granulation in the process of rotation by controlling the weight ratio of slag and granulation medium, and produces solid slag block with particle size of 20-100mm and temperature of 600-900℃, and uses cooling unit to cool granulation medium in situ or in circulation, to realize medium recycling.

Description

Technical Field

[0001] This invention relates to the field of solid waste treatment technology in the iron and steel metallurgy industry, and more specifically, to a chamber-type slag granulation device and process. Background Technology

[0002] Steel slag is a major solid waste generated during steel smelting, accounting for approximately 15%-20% of crude steel production. Its discharge temperature typically reaches 1400-1650℃, containing a large amount of high-grade sensible heat and possessing extremely high recycling value. With the deepening of the green and low-carbon transformation of the steel industry, the country has placed higher demands on the comprehensive utilization rate of solid waste and energy consumption per unit product. How to efficiently, safely, and environmentally treat high-temperature steel slag and recover its heat energy has become a key technical problem that the industry urgently needs to solve.

[0003] Currently, the main pretreatment methods for high-temperature steel slag are as follows:

[0004] (1) Roller crushing method: High-temperature molten slag is crushed by mechanical roller crushing. The processing cycle is about 30 minutes and the particle size range is 0-300mm. The main problems of this method are: the particle size distribution is extremely wide and uncontrollable, the long processing cycle leads to a large equipment footprint; key components such as the roller surface need to be in direct contact with high-temperature molten slag, which is easily damaged and the maintenance cost is high; the molten slag is in direct contact with water during the roller crushing process, which poses a high risk of explosion; its granulation product is a mixed material with a wide distribution, which is difficult to directly match with downstream waste heat recovery devices (such as slag coolers and waste heat boilers). Large slag pieces are prone to causing blockage of the feed inlet, while fine powder affects the heat exchange efficiency.

[0005] (2) Baosteel drum process: The slag is granulated by the impact and grinding action of steel balls inside the drum. The processing cycle is about 30 minutes, and 80% of the product particles are less than 10 mm in diameter. However, the yield of coarse aggregate (10-50 mm) is extremely low. This process requires a large amount of water spraying for cooling, which makes it difficult to recover the sensible heat of the slag. Most of the heat is lost in the form of steam, and the product has a high water content (usually >10%). Additional dehydration treatment is required before it can be used in building materials or landfills, which increases the energy consumption and cost of the process.

[0006] (3) Air quenching method: High-speed airflow is used to disperse and granulate the molten slag. The process is completed instantaneously, and the product particle size is about 5 mm. Fine powder can be produced, but coarse aggregate cannot be generated. This method has high air consumption and high power consumption, with power consumption reaching 30-50 kWh per ton of slag. The fine powder is easy to fly, and dust control is difficult, requiring a large and complex dust removal system. In addition, the airflow cooling efficiency is limited. The molten slag only solidifies rapidly on the surface, and the internal heat is difficult to recover effectively, resulting in low sensible heat recovery value.

[0007] (4) Water quenching method: High-temperature molten slag is directly poured into water for rapid cooling. The process is completed instantaneously, and the product is glassy fine sand (particle size about 5 mm). It has a high content of fine powder and cannot produce aggregate. This method generates a large amount of steam and releases harmful gases such as hydrogen sulfide when the molten slag comes into direct contact with water, posing an extremely high risk of explosion; it also consumes a large amount of water (approximately 10 m³ of water per ton of slag). 3 Furthermore, it generates wastewater containing heavy metal ions, resulting in high treatment costs. Currently, some countries have banned the use of this method to treat steel slag due to environmental and safety considerations.

[0008] The aforementioned existing technologies generally share the following common problems:

[0009] Uncontrollable particle size: The products are mostly fine powder or wide-distribution mixed materials, making it difficult to produce high-value coarse aggregate (10-50mm), and it is also impossible to accurately adjust the particle size range according to different resource utilization uses (such as producing micro powder for cement admixtures, 5-10mm for asphalt pavement aggregates, 10-40mm for concrete aggregates or road construction materials).

[0010] Sensible heat recovery is difficult: large amounts of water or forced air cooling lead to the loss of high-grade waste heat, the product temperature is uncontrollable, and the slag discharge temperature is often below 200℃ or fluctuates, which is difficult to match with the continuous and stable feeding requirements of downstream waste heat recovery devices (such as rotary slag coolers and waste heat boilers, which usually require temperatures above 600℃ to ensure steam quality).

[0011] High safety and environmental risks: direct contact between molten slag and water can easily cause violent explosions, and produce harmful gases such as H2S and SO2, as well as wastewater containing heavy metals, resulting in high treatment costs;

[0012] Long processing cycle: Some methods require 30 minutes or even longer to process a single batch, making it difficult to achieve continuous operation that matches the steelmaking production rhythm (about 30-40 minutes to produce a furnace of steel).

[0013] Therefore, developing a pretreatment equipment capable of rapid, continuous, and controllable granulation of high-temperature molten slag, with precisely adjustable product particle size (0-100mm, especially producing 10-40mm high-value-added aggregate), controllable discharge temperature (600-900℃, retaining high-grade sensible heat), safety and environmental protection (no direct water contact, low water consumption, zero emissions), and seamless integration with downstream waste heat recovery devices, has become a critical technological bottleneck that urgently needs to be overcome in the field of steel slag resource utilization. Summary of the Invention

[0014] In order to overcome the above-mentioned defects of the prior art, the embodiments of the present invention provide a cavity-type slag granulation device and process method. The technical problem to be solved by the present invention is: how to achieve precise control of product particle size, effective recovery of high-grade sensible heat, and seamless connection with downstream waste heat recovery device while rapidly, continuously and safely granulating high-temperature molten slag.

[0015] To achieve the above objectives, the present invention provides the following technical solution: a chamber-type slag granulation device, comprising:

[0016] The rotating body is uniformly divided into 3 to 12 independent, modular granulation chambers along the circumference. Each granulation chamber contains a predetermined capacity of granulation medium, which is a metal ball or a metal rod, and serves as a heat exchange and crushing medium.

[0017] A modular water-cooled grate is installed on the outside of each of the granulation chambers to receive high-temperature liquid slag and solid slag within a certain particle size range as it enters the granulation chamber (3-b) and withstands the direct scouring of the high-temperature slag. The modular water-cooled grate is a structure that can be independently disassembled and replaced.

[0018] A membrane water-cooled wall shell is sealed around the outside of the rotating body and connected to a waste heat recovery system to absorb and recover the radiant and conductive heat released by the slag during the granulation process.

[0019] The receiving station is located above or to the side of the rotating body and is used to receive high-temperature slag at about 1450°C and introduce it into the granulation chamber located at the station.

[0020] The unloading station is located below or to the side of the rotating body and is used to discharge solid slag that has been granulated and cooled to 600-900°C.

[0021] The granulation medium cooling unit is located after the unloading station and before the receiving station. It is used to force-cool the high-temperature granulation medium remaining inside the granulation chamber after the solid slag is emptied, so that its temperature is reduced to below 300°C for the next cycle.

[0022] The granulated medium cooling unit includes at least one of the following two forms:

[0023] In-situ cooling method: including a spraying device or blowing device installed on the path after the unloading station, used to directly spray cooling water or blow cooling gas onto the high-temperature granulation medium remaining in the granulation chamber.

[0024] The circulating cooling system includes a granulation medium discharge valve connected to the granulation chamber, a granulation medium lifting conveyor, an external granulation medium cooler, and a granulation medium backfilling device. This system is used to discharge all or part of the granulation medium from the chamber after unloading, and then refill it into the same chamber after external cooling.

[0025] The present invention also includes a cavity-type slag granulation process, comprising the following cyclically executed steps:

[0026] S1. Receiving Step: Rotate the rotating body to move the unloaded granulation chamber, whose granulation medium temperature has been cooled to a preset temperature, to the receiving station, and inject a mass of [missing information] into the chamber. High-temperature slag at around 1450℃;

[0027] S2, Granulation and Heat Exchange Step: Continue rotating the rotating body to move the granulation chamber loaded with slag away from the receiving station and sequentially through multiple heat exchange positions. Simultaneously, activate the circulating cooling of the membrane water-cooled wall shell to recover heat energy. During this process, control the quality of the injected slag. With the quality of the granulated medium in the chamber weight ratio Between 0.10 and 0.20, the slag and granulation medium are in full contact and exchange heat. The slag temperature drops from about 1450℃ to 600-900℃ within a predetermined time and solidifies into solid slag blocks with a particle size of 20-100mm, while the temperature of the granulation medium rises from the initial room temperature to no more than 300℃.

[0028] S3. Unloading step: Rotate the granulation chamber containing solid slag and high-temperature granulation medium to the unloading position, and use gravity to discharge the solid slag through the modular water-cooled grate, while the high-temperature granulation medium is retained in the chamber.

[0029] S4. Granulation medium cooling step: After unloading is completed, the granulation chamber is moved out of the unloading position, and the granulation medium cooling unit is started to force the high temperature granulation medium in the chamber to cool it back to the preset temperature for the next cycle.

[0030] In a preferred embodiment, the wall panel of the granulation chamber is a water-cooled sandwich structure or a high-temperature resistant metal plate structure, and it is fixed to the main body of the rotating body by a detachable quick-connect fitting to achieve rapid replacement of the entire granulation chamber. This design allows for easy replacement of a single granulation chamber without disassembling the entire rotating body when a chamber is damaged due to long-term thermal fatigue or mechanical wear, simply by replacing the module online or offline, significantly reducing maintenance time and costs. Simultaneously, the modular water-cooled grate integrates independent inlet and outlet water interfaces, and its internal cooling medium is connected to or independently set with the cooling system of the membrane water-cooled wall shell. The grate bar gap is preferably 20-100mm, but can also be flexibly adjusted according to the specific particle size requirements of the tailings. By replacing grate modules with different grate gaps, the maximum particle size of the final discharged solid slag can be flexibly controlled (for example, using a 40mm gap grate will produce slag with a maximum size of approximately 40mm), thus achieving product particle size adjustment.

[0031] In a preferred embodiment, a subsequent heat exchange unit is also included. This subsequent heat exchange unit is a plate chain conveyor, a rotary slag cooler, or a solid heat exchanger. Its inlet is connected to the unloading station to receive solid slag blocks at 600-900°C and further cool them to below 100°C to deeply recover the sensible heat of the solid slag blocks. This subsequent unit can be a moving bed or fluidized bed heat exchanger using water or air as the cooling medium. It can recover the remaining medium and low temperature heat of the slag blocks for preheating combustion air, producing hot water or low temperature steam, thereby realizing the cascade utilization of heat and maximizing the heat recovery efficiency of the entire system.

[0032] In a preferred embodiment, in the granulation heat exchange step, the weight ratio of slag to granulation medium is controlled. The ratio is set to 0.10, 0.12, 0.15, 0.18, or 0.20, and the rotational speed of the rotating body is controlled at 0.5-5 rpm, so that the total residence time of each granulation chamber from the receiving station to the unloading station is 6-60 seconds. By adjusting this ratio, the particle size of the final slag can be precisely controlled: the lower the ratio (e.g., 0.10), the more granulation medium there is, the stronger the crushing effect, and the smaller the output particle size (e.g., 20-40mm); the higher the ratio (e.g., 0.20), the larger the output particle size (e.g., 60-100mm). At the same time, the residence time setting ensures that the slag has enough time to complete the solidification and granulation process, adapting to different slag volumes and process rhythms.

[0033] In a preferred embodiment, when the granulation medium cooling step adopts in-situ cooling, the flow rate and time of cooling water or cooling gas are controlled to cool the granulation medium to 100-300°C before it reaches the receiving station in the next cycle. The advantage of in-situ cooling is its simple structure and the absence of a medium conveying device, but the cooling effect is limited by the space and heat exchange area within the chamber. When a circulating cooling method is adopted, the following sub-steps are also included: opening the discharge valve of the granulation chamber to discharge all the high-temperature granulation medium; sending the discharged high-temperature granulation medium to an external granulation medium cooler (such as a rotary cooling cylinder or fluidized bed cooler) via a lifting conveyor (such as a bucket elevator or screw conveyor) to cool it to below 100°C using water cooling or air cooling; and refilling the cooled granulation medium into the same granulation chamber via a backfilling device. The circulating cooling method has higher cooling efficiency and can cool the granulation medium to near ambient temperature, thereby providing greater heat exchange driving force in the next cycle. It is suitable for scenarios with large processing volumes or extremely high requirements for slag temperature stability.

[0034] In a preferred embodiment, after the unloading step, a secondary cooling step is further included: the discharged 600-900℃ solid slag blocks are sent to a subsequent heat exchange unit to further cool them to below 100℃ or even room temperature, and the final recovered heat energy grade is adjusted by controlling the flow rate of the cooling medium in the subsequent heat exchange unit; this enables the entire system to not only recover high-temperature radiant heat (through the membrane water-cooled wall), but also recover the medium-temperature sensible heat of the solid slag blocks, realizing the graded recovery and comprehensive utilization of high-quality waste heat and medium- and low-quality waste heat.

[0035] In a preferred embodiment, during the granulation heat exchange step, the slag undergoes three heat exchange processes simultaneously within the granulation chamber: first, direct contact heat conduction between the slag and the granulation medium, which is the most important heat exchange method because the metal balls / rods have a large contact area and high thermal conductivity with the molten slag; second, radiative heat exchange between the slag and the granulation chamber wall, especially when the slag is still in a molten or semi-molten state in the first half, where radiative heat exchange makes a significant contribution; and third, the heat released by the slag is radiated and conducted to the external membrane water-cooled wall shell through the granulation chamber wall and the rotating shell. Simultaneously, during the cooling and solidification process, the slag is crushed into high-value coarse aggregate due to mechanical collision with the granulation medium and its own thermal stress.

[0036] The technical effects and advantages of this invention are as follows:

[0037] 1. This invention, by providing a rotating body and its independent granulation chambers, combined with a spatial layout of multiple functional stations such as receiving, granulation heat exchange, unloading, and medium cooling, realizes continuous and automated operation of the high-temperature slag granulation process; each chamber cyclically executes different processes, eliminating waiting time in batch processing, matching the slag discharge rhythm of the steelmaking furnace, with a short processing cycle and high equipment utilization.

[0038] 2. This invention introduces metal balls or metal rods as granulation media and precisely controls the weight ratio of slag to media to achieve precise control of product particle size. It can produce high-value-added coarse aggregate in the range of 20-100mm according to market demand, thereby improving the resource utilization value of steel slag. It can be directly used as high-performance concrete aggregate or road construction material.

[0039] 3. This invention uses a membrane water-cooled wall shell to directly exchange radiation and convection heat with high-temperature slag blocks, recovering high-quality heat released during granulation, while producing solid slag blocks with a temperature of 600-900℃, retaining their high-grade sensible heat; slag blocks in this temperature range can be directly and stably fed into subsequent waste heat boilers or solid heat exchangers for deep heat recovery, solving the problem of product temperature being too low or fluctuating and difficult to match with downstream equipment;

[0040] 4. In the entire process of this invention, the molten slag is only briefly exposed to the air when receiving the material. Granulation heat exchange and unloading are carried out in a relatively sealed space composed of the membrane water-cooled wall shell and the rotating body itself. The solid slag block after unloading contains no water or only adsorbs a small amount of water on its surface, which avoids the risk of violent explosion caused by direct contact between molten slag and a large amount of water in traditional water quenching or rolling processes. At the same time, it also eliminates the generation of harmful gases and wastewater containing heavy metals. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0042] Figure 2 This is a schematic diagram of the rotating body and granulated medium cooling unit structure of the present invention.

[0043] Figure 3 This is a schematic diagram of the rotating body structure of the present invention.

[0044] Figure 4 This is a schematic diagram of the three-dimensional structure of the rotating body of the present invention.

[0045] The attached figures are labeled as follows: 1 receiving station, 2 membrane water-cooled wall shell, 3 rotating body, 4 unloading station, 5 granulation medium cooling unit, and 6 subsequent heat exchange unit.

[0046] 3-a Modular water-cooled grate, 3-b Modular granulation chamber, 3-c Granulation medium. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] Example 1:

[0049] This embodiment provides a chambered slag granulation device, which is specifically designed to process high-temperature liquid steel slag at 1400-1650℃ produced by steelmaking converters.

[0050] Please see Figures 1 to 4This invention includes a large-diameter horizontal rotating body 3. The main body of the rotating body 3 is a hollow cylindrical shell, whose interior is uniformly divided circumferentially into 10 independent, modular granulation chambers 3-b. Each granulation chamber 3-b is approximately a fan-shaped prism, separated by partitions welded from wear-resistant and heat-resistant steel plates. The wall panels of each chamber 3-b adopt a water-cooled sandwich structure, with circulating cooling water flowing through the sandwich to protect the metal shell and assist in heat recovery. More importantly, each modular granulation chamber 3-b is fixed to the main body of the rotating body 3 using quick-connect fittings consisting of high-strength bolts and locating pins. When a chamber is damaged due to long-term thermal fatigue or mechanical impact, it can be disassembled and replaced individually without the need for complete scrapping, significantly reducing maintenance costs.

[0051] A modular water-cooled grate 3-a is installed on the outer side of each granulation chamber 3-b (i.e., towards the outer circumference of the rotating body 3). In this embodiment, the grate bars are made of high-chromium heat-resistant steel, and the grate gap is set to 50mm. The modular water-cooled grate 3-a integrates independent cooling water channels and is connected to an external circulating water system through independent inlet and outlet water interfaces, enabling it to maintain structural strength and dimensional stability while withstanding direct scouring by high-temperature slag. The grate 3-a is also a modular design, and the maximum particle size of the final product can be adjusted by replacing modules with different grate gaps (e.g., 40mm, 60mm, and 80mm specifications).

[0052] The rotating body 3 is completely enclosed by a fixed, sealed membrane water-cooled wall shell 2. The membrane water-cooled wall shell 2 is welded from multiple parallel steel pipes and flat steel bars to form a fully welded membrane wall structure, with circulating cooling water (or a steam-water mixture) flowing inside. The upper part of the shell 2 has a steam outlet, and the lower part has a water inlet, which connects to the plant's waste heat recovery system (such as a deaerator or steam drum). When the high-temperature slag is granulated and cooled inside the rotating body 3, the large amount of radiant heat released and the heat conducted through the chamber wall are absorbed by the membrane water-cooled wall shell 2, generating low-pressure saturated steam, thus achieving effective heat recovery.

[0053] In terms of the spatial layout of the device, a fixed receiving station 1 is located at the top, and its inlet is connected to the slag outlet or slag pot of the steelmaking furnace above via a chute. Below the rotating body 3, there is a discharge station 4, whose outlet is directly and sealed to the inlet of the subsequent heat exchange unit 6 (in this embodiment, a rotary heat exchanger is used). A granulation medium cooling unit 5 is located on the rotation path of the rotating body 3 after the discharge station 4 and before the receiving station 1. In this embodiment, the cooling unit 5 adopts an in-situ cooling method, specifically a nozzle array arranged on both sides of the rotating body 3. When the granulation chamber 3-b passes through this area, the nozzles spray atomized cooling water onto the high-temperature granulation medium 3-c in the chamber, forcibly cooling it.

[0054] Each granulation chamber 3-b contains a predetermined volume of granulating medium 3-c. In this embodiment, the granulating medium 3-c is selected from wear-resistant alloy steel balls with a diameter of 75-150 mm. The filling volume of the steel balls in each chamber is approximately 40% of the chamber volume, and the total mass is approximately [missing information]. .

[0055] The working principle and process of the device in this embodiment are as follows, including a cyclically executed process flow:

[0056] S1, Material Receiving Steps

[0057] Start the drive unit to make the rotating body 3 rotate counterclockwise at a speed of 1 revolution per minute. Figure 1 (Viewpoint) Continuous rotation. The position detection system (such as an encoder) of the rotating body 3 provides real-time feedback on the position of each chamber. When an empty granulation chamber 3-b, whose granulation medium 3-c has been cooled to approximately 150°C in the previous cycle, moves directly below the receiving station 1, the control system issues a command to inject a mass of [missing information] into the chamber via a weighing chute. The high-temperature liquid steel slag at approximately 1450°C. In this embodiment, control... This makes the weight ratio of slag to steel balls... The high-temperature molten slag passes through the grate openings of the modular water-cooled grate 3-a and rapidly flows into the gaps of the granulated medium 3-c (steel balls) and covers the surface of the steel balls.

[0058] S2, Granulation heat exchange step

[0059] As the rotating body 3 continues to rotate, the granulation chamber 3-b, loaded with molten slag, leaves the receiving station 1 and begins its cycle of approximately 0.5 minutes (since one rotation takes 1 minute, the distance from the receiving station 1 to the unloading station 4 passes through approximately 5-6 chamber positions; the actual dwell time can be adjusted by changing the rotation speed and station layout as needed). During this period, the chamber passes through several different circumferential positions sequentially. Intense heat exchange occurs between the molten slag and the cold steel balls. The heat from the molten slag is transferred through three pathways: ① direct conduction to the steel balls in contact with it; ② radiation to the chamber walls; ③ radiation and conduction through the chamber walls and the rotating body shell to the external membrane water-cooled wall shell 2. The circulating water inside the membrane water-cooled wall shell 2 continuously carries away heat, generating steam which is then incorporated into the piping network.

[0060] Under the influence of heat exchange and the mechanical disturbance of the steel balls, the molten slag rapidly cools and solidifies. Since the weight ratio of slag to steel balls is precisely controlled at 0.15, and the specific heat capacity and thermal capacity of the steel balls are much greater than those of the slag, they can absorb sufficient heat to reduce the slag temperature from 1450℃ to the target range. Simultaneously, the slag generates thermal stress due to volume shrinkage during solidification, and undergoes continuous collisions with the steel balls during rotation and tumbling. These stresses cause the solidified slag shell to break. Because the grate gap of the modular water-cooled grate 3-a is 50mm, slag lumps larger than 50mm are blocked or further broken by the steel balls until they can pass through the grate. When the chamber rotates to the unloading station 4, the slag has completely solidified and been broken into solid slag lumps with a particle size mostly between 30-50mm, with a measured temperature of approximately 750-800℃. At the same time, the steel balls, having absorbed heat from the slag, rise in temperature from the initial 150℃ to approximately 280℃, not exceeding the design upper limit of 300℃.

[0061] S3, Unloading Steps

[0062] When the granulation chamber 3-b, which carries solid slag and high-temperature steel balls, rotates to the bottom unloading station 4, the solid slag is discharged through the grate openings of the modular water-cooled grate 3-a under gravity and falls onto the subsequent heat exchange unit 6 below. Meanwhile, the steel balls, with a diameter of 75-150mm, are larger than the grate openings, and all the steel balls are effectively trapped within the granulation chamber 3-b.

[0063] S4, Granulation medium cooling step

[0064] After unloading, the granulation chamber 3-b continues to rotate upwards with the rotating body 3, leaving the unloading station 4. When it enters the working area of ​​the granulation medium cooling unit 5, the spray device located there automatically starts, spraying atomized cooling water directly onto the steel balls in the chamber. The water flow rate and spraying time are precisely adjusted by a PID control loop (e.g., spraying for 30 seconds) to ensure that the steel ball temperature is uniformly cooled to a preset 150°C before reaching the next receiving station 1. The water vapor generated during the cooling process is discharged or recovered through the exhaust port provided on the membrane water-cooled wall shell 2. At this point, a complete processing cycle ends, and the chamber is ready to receive the next batch of high-temperature slag.

[0065] S5, Secondary Cooling Step

[0066] Solid slag blocks at 750-800℃ discharged from unloading station 4 fall into a rotary heat exchanger (subsequent heat exchange unit 6). The outer wall of this rotary heat exchanger is a membrane water-cooled wall structure, with cooling water circulating inside. During forward transport, the slag blocks indirectly exchange heat with the cooling water, gradually reducing their temperature. By controlling the transport speed and cooling water flow rate, the temperature of the slag blocks at the outlet can be ensured to be below 100℃, and even reduced to within 50℃ of ambient temperature. The medium- and low-temperature heat recovered from the slag blocks can be used to preheat boiler feedwater or for plant heating, and can even generate steam, further improving the overall system's thermal efficiency.

[0067] Example 2:

[0068] This embodiment is basically the same as embodiment 1, except that the granulated medium 3-c is made of heat-resistant steel rods with a diameter of 75-150mm (short rods, with a length slightly less than the thickness of the chamber), and the grate gap of the modular water-cooled grate 3-a is adjusted to 80mm.

[0069] Using steel bars instead of steel balls, the steel bars rotate within the chamber with the rotating body. Besides colliding with each other, they also produce shearing and grinding-like effects, resulting in a stronger ability to crush slag, especially suitable for processing high-viscosity, difficult-to-crush steel slag. This can be achieved by adjusting the weight ratio of slag to steel bars. With a particle size of 0.12 and an 80mm grate gap, the final solid slag particles are distributed between 50-80mm, with regular shapes, making them very suitable as large-diameter roadbed aggregate. This embodiment further demonstrates that by simply adjusting the medium type and grate gap, it is possible to flexibly adapt to different slag characteristics and product market demands.

[0070] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0071] Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other.

[0072] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A chamber-type slag granulation device, characterized in that, include: The rotating body (3) is uniformly divided into 3 to 12 independent, modular granulation chambers (3-b) along the circumference. Each granulation chamber (3-b) contains a predetermined capacity of granulation medium (3-c), which is a metal ball or a metal rod, and serves as a heat exchange and crushing medium. A modular water-cooled grate (3-a) is installed on the outside of each of the granulation chambers (3-b) to receive high-temperature liquid slag and solid slag within a certain particle size range as it enters the granulation chamber (3-b) and is subjected to direct scouring by the high-temperature slag. The modular water-cooled grate (3-a) is a structure that can be independently disassembled and replaced. The membrane water-cooled wall shell (2) is sealed to the outside of the rotating body (3) and connected to the waste heat recovery system for absorbing and recovering the radiant heat and conductive heat released by the slag during the granulation process. The receiving station (1) is located above or to the side of the rotating body (3) for receiving high-temperature slag at 1450°C and introducing it into the granulation chamber (3-b) located at the station. The unloading station (4) is located below or to the side of the rotating body (3) and is used to discharge solid slag that has been granulated and cooled to 600-900°C. Granulation medium cooling unit (5) is set after the unloading station (4) and before the receiving station (1). It is used to force cool the high temperature granulation medium (3-c) remaining in the granulation chamber (3-b) after the solid slag is discharged, so that its temperature is reduced to below 300°C for the next cycle. The granulated medium cooling unit (5) includes at least one of the following two forms: In-situ cooling method: including a spraying device or blowing device installed on the path after the unloading station (4) for directly spraying cooling water or blowing cooling gas onto the high-temperature granulation medium (3-c) remaining in the granulation chamber (3-b); The circulating cooling system includes a granulation medium discharge valve connected to the granulation chamber (3-b), a granulation medium lifting conveyor, an external granulation medium cooler, and a granulation medium backfilling device, which are used to discharge all or part of the granulation medium (3-c) from the chamber after unloading, and then refill it into the same chamber after external cooling.

2. The chamber-type slag granulation device according to claim 1, characterized in that: The wall panel of the granulation chamber (3-b) is a water-cooled sandwich structure or a high-temperature resistant metal plate structure. It is fixed to the main body of the rotating body (3) by a detachable quick connector to realize the overall quick replacement of a single granulation chamber (3-b).

3. The chamber-type slag granulation device according to claim 1, characterized in that: The modular water-cooled grate (3-a) is integrated with independent inlet and outlet water interfaces. The cooling medium inside it is connected to or independently set with the cooling system of the membrane water-cooled wall shell (2). The gap between the grate bars is 20-100mm.

4. The chamber-type slag granulation device according to claim 1, characterized in that: It also includes a subsequent heat exchange unit (6), which is a plate chain conveyor, a rotary slag cooler or a solid heat exchanger. Its inlet is connected to the unloading station (4) to receive solid slag blocks at 600-900℃ and further cool them to below 100℃ in order to deeply recover the physical sensible heat of the solid slag blocks.

5. A process method based on the chambered slag granulation device according to any one of claims 1-4, characterized in that, Includes the following steps executed in a loop: S1, Receiving Step: Rotate the rotating body (3) to move the empty granulation chamber (3-b) whose granulation medium (3-c) has been cooled to the preset temperature to the receiving station (1), and inject a mass of [missing information] into the chamber. High-temperature slag at 1450℃; S2, Granulation heat exchange step: Continue rotating the rotating body (3) so that the granulation chamber (3-b) loaded with slag leaves the receiving station (1) and passes through multiple heat exchange positions in sequence. At the same time, the circulating cooling of the membrane water-cooled wall shell (2) is started to recover heat energy. During this process, the mass of injected slag is controlled. Mass of granulated media (3-c) within the chamber weight ratio Between 0.10 and 0.20, the slag and the granulation medium (3-c) are in full contact for heat exchange. The slag temperature drops from 1450℃ to 600-900℃ within a predetermined time and solidifies into solid slag blocks with a particle size of 20-100mm, while the temperature of the granulation medium (3-c) rises from the initial room temperature to no more than 300℃. S3. Unloading step: Rotate the granulation chamber (3-b) carrying solid slag and high-temperature granulation medium (3-c) to the unloading station (4), and use gravity to discharge the solid slag through the modular water-cooled grate (3-a), while the high-temperature granulation medium (3-c) is retained in the chamber. S4. Granulation medium cooling step: After unloading is completed, the granulation chamber (3-b) is moved out of the unloading station (4), and the granulation medium cooling unit (5) is started to force-cool the high temperature granulation medium (3-c) in the chamber to restore its temperature to the preset temperature for the next cycle.

6. The method for granulation of slag in a divided chamber according to claim 5, characterized in that: In the granulation heat exchange step S2, the weight ratio of slag to granulation medium is controlled. The value is 0.10, 0.12, 0.15, 0.18 or 0.20, and the rotation speed of the rotating body (3) is controlled to be 0.5-5 revolutions / minute, so that the total residence time of each granulation chamber (3-b) from the receiving station (1) to the unloading station (4) is 6-60 seconds, during which the slag completes the granulation and solidification process.

7. The method for granulation of slag in a divided chamber according to claim 5, characterized in that: When the granulation medium cooling step in step S4 adopts in-situ cooling, the flow rate and time of cooling water or cooling gas are controlled so that the granulation medium (3-c) is cooled to 100-300℃ before reaching the receiving station (1) in the next cycle.

8. The method for granulation of slag in a divided chamber according to claim 5, characterized in that: When the granulation medium cooling step in step S4 adopts the circulating cooling method, it further includes the following sub-steps: S4.1: Open the discharge valve of the granulation chamber (3-b) to discharge all the high-temperature granulation medium (3-c); S4.2: The discharged high-temperature granulated medium (3-c) is sent to an external granulated medium cooler by a lifting conveyor, and cooled to below 100°C by water or air cooling; the cooled granulated medium (3-c) is then refilled into the same granulation chamber (3-b) by a backfilling device.

9. The method for granulation of slag in a divided chamber according to claim 5, characterized in that: After the unloading step in step S3, a secondary cooling step is also included: the discharged 600-900℃ solid slag block is sent to the subsequent heat exchange unit (6), which is a plate chain conveyor, a rotary slag cooler or a solid heat exchanger, to further cool it to below 100℃ or even room temperature, and the final recovered heat energy grade is adjusted by controlling the flow rate of the cooling medium in the subsequent heat exchange unit (6).

10. The method for granulation of slag in a divided chamber according to claim 5, characterized in that: In the granulation heat exchange step S2, three heat exchange processes occur simultaneously in the granulation chamber (3-b): first, direct contact heat conduction between the slag and the granulation medium (3-c); second, radiation heat exchange between the slag and the wall plate of the granulation chamber (3-b); and third, radiation and conduction heat exchange of the heat released by the slag to the outer membrane water-cooled wall shell (2) through the wall plate of the granulation chamber (3-b) and the shell of the rotating body (3). Furthermore, during the cooling and solidification process, the slag is crushed into high-value coarse aggregate due to mechanical collision with the granulation medium (3-c) and its own thermal stress.

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