Method for hot stuffing of steel slag and hot stuffing tank with pressure

Abstract

The present invention proposes a method for hot stuffing of steel slag and a pressurized hot stuffing tank, comprising the following steps: first, steel slag is loaded into a pressurized hot stuffing tank, the pressurized hot stuffing tank is sealed, water is added to the pressurized hot stuffing tank for hot stuffing treatment, when the pressure in the pressurized hot stuffing tank reaches the target pressure value and the temperature is within the target temperature range, a steel bar is used to insert a hole in the steel slag in the pressurized hot stuffing tank from the side in the horizontal direction, and then the steel bar is pulled out, within the target pressure value range, the steel slag temperature in the pressurized hot stuffing tank does not exceed 65°C, and when the time of not exceeding 65°C reaches 2-2.5h, the hot stuffing ends, water is stopped, exhaust is exhausted and pressure is relieved, and nitrogen is filled into the pressurized hot stuffing tank at the same time, when the difference between the pressure in the pressurized hot stuffing tank and the atmospheric pressure is 0Mpa, and there is no water mist in the exhaust gas, the tank is opened and the slag is discharged. The particle size distribution of the steel slag slag particles obtained by the hot stuffing method of the present invention is more concentrated, the particle differentiation effect is good, and the operation of secondary crushing is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgy, and in particular to a method for hot stuffing of steel slag and a pressurized hot stuffing pot. Background Art

[0002] Steel slag is a mixture of slag and a small amount of residual steel produced in the steelmaking process. The residual steel that cannot be recovered by magnetic separation is mixed with different impurities and is difficult to separate. There are currently a variety of steel slag treatment technologies, mainly including hot pouring, granulation and hot stuffing. Among them, the hot stuffing method has a wider applicability, low energy consumption, and the tailings produced are relatively stable and can basically be fully utilized, so it is widely used.

[0003] The principle of the hot stuffing method is to use supersaturated steam to contact the steel slag to produce a physical and chemical reaction. When the temperature changes, different phases in the steel slag expand or contract to different degrees, thereby crushing and separating different substances. However, the hot stuffing method needs to be carried out in a hot stuffing container, and water can only be added from one direction. After the upper layer of steel slag that first contacts the water is pulverized, the lower layer of steel slag has the opportunity to contact the water and pulverize. In the process of heat transfer, there will inevitably be uneven transfer problems, so there will be incomplete local pulverization and poor iron slag separation, which is not conducive to the subsequent treatment of steel slag and the improvement of recycling rate. Summary of the invention

[0004] In view of this, the present invention proposes a method for hot stuffing of steel slag, aiming to solve the problem of incomplete pulverization during the hot stuffing treatment of steel slag.

[0005] The technical solution of the present invention is achieved as follows: The present invention provides a method for hot stuffing of steel slag, comprising the following steps:

[0006] Step 1: put the steel slag into a pressure-heating tank, seal the pressure-heating tank, and add water into the pressure-heating tank for heat-stifling treatment;

[0007] Step 2: When the pressure in the autoclave reaches the target pressure value and the temperature is within the target temperature range, use a steel chisel to insert a hole into the steel slag in the autoclave from the side in the horizontal direction, and then pull out the steel chisel;

[0008] Step 3: within the target pressure range, heat and stuff until the temperature of the steel slag in the pressurized hot stuffing tank does not exceed 65°C, and the time of not exceeding 65°C reaches 2-2.5h, the heat and stuffing is completed, and the water addition and exhaust pressure relief are stopped, and nitrogen is filled into the pressurized hot stuffing tank at the same time;

[0009] Step 4: When the difference between the pressure in the pressurized hot tank and the atmospheric pressure is 0 MPa and there is no water mist in the exhaust gas, open the tank and remove the slag.

[0010] In some embodiments, the target pressure value is 0.2-0.25 MPa, and the target temperature range is 750-1000°C.

[0011] In some embodiments, in step 2, the step of using a steel bar to drill a hole in the steel slag in the autoclave from the side along the horizontal direction includes: when the temperature in the autoclave reaches the upper limit of the target temperature range, at least one steel bar is inserted into at least one side of the steel slag in the horizontal direction 100-200 mm below the top of the steel slag; when the temperature in the autoclave reaches the median value of the target temperature range, at least one steel bar is inserted into at least one side of the steel slag in the horizontal direction at the middle position of the steel slag in the vertical direction; when the temperature in the autoclave reaches the lower limit of the target temperature range, at least one steel bar is inserted into at least one side of the steel slag in the horizontal direction 100-200 mm above the bottom of the steel slag.

[0012] In some embodiments, in step 2, when a steel bar is used to insert a hole into the steel slag in the autoclave from the side along a horizontal direction, the steel bar is kept in the steel slag for 1-3 minutes and then the steel bar is pulled out.

[0013] In some embodiments, the cross section of the steel chisel is circular, and the diameter of the steel chisel is 4-6 cm.

[0014] In some embodiments, the volume of the autoclave is 10-15 m 3 When hot and stuffy treatment, the water adding speed is 18-24m 3 / h.

[0015] Another object of the present invention is to provide a pressurized hot stuffing pot for use in a hot stuffing treatment method for steel slag. The use of the pressurized hot stuffing pot can improve the degree of pulverization of the steel slag after the hot stuffing treatment.

[0016] The structure of the pressurized hot stuffy tank comprises: a tank body, a cover plate, a steel drill and a steel drill driving device. The tank body has an opening at the top, the cover plate is movably installed at the opening at the top of the tank body, the cover plate selectively seals the opening at the top of the tank body, a plurality of steel drill holes are opened in the horizontal direction on the side wall of the tank body, a steel drill is embedded in each steel drill hole, the steel drill is dynamically sealed with the inner wall of the steel drill hole, the steel drill driving device is arranged on the outside of the tank body, the steel drill driving device drives the steel drill to reciprocate along the opening direction of the steel drill hole, an air inlet, an air outlet and a water inlet are opened on the surface of the cover plate, a first water outlet is opened on the side of the tank body, and a second water outlet is opened on the bottom of the tank body.

[0017] In some embodiments, the number of the second water outlets is not less than two, and the plurality of second water outlets are arranged in an array along the circumference of the tank body at the bottom of the tank body.

[0018] In some embodiments, at least three layers of steel drill holes are opened at equal intervals along the vertical direction on the side of the tank body, and the number of steel drill holes in each layer is not less than one.

[0019] In some embodiments, the number of steel drill holes in each layer is not less than two, and the multiple steel drill holes in each layer are arranged in an array with equal intervals along the circumference of the tank body.

[0020] In some embodiments, a liquid level sensor and a temperature sensor are installed inside the tank body, and both the liquid level sensor and the temperature sensor are connected to the control device outside the tank body by signal.

[0021] The method for hot stuffing of steel slag of the present invention has the following beneficial effects compared with the prior art:

[0022] The steel slag hot stuffing method of the present invention performs hole processing on the side of the steel slag during the hot stuffing process. The holes formed by the holes can provide horizontal penetration channels for water and supersaturated steam. On the one hand, the horizontal holes can allow the steel slag at different positions in the same horizontal plane to maintain the same reaction process as much as possible. Secondly, the water and supersaturated steam that penetrate in the horizontal direction can make the steel slag close to the inner wall of the pressure hot stuffing tank more likely to participate in the reaction, thereby preventing the steel slag close to the inner wall of the pressure hot stuffing tank from being unable to contact with water or steam in time and being unable to be completely pulverized.

[0023] The present invention also provides a pressurized hot stuffing tank for hot stuffing treatment of steel slag. By opening a hole in the side wall of the tank body and embedding a dynamically sealed steel chisel in the hole, the steel chisel can be used to perform hole insertion treatment on the steel slag during the hot stuffing treatment of the steel slag in the pressurized hot stuffing tank, so that the steel slag in the same horizontal plane can be more evenly contacted with water or steam for reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 The present invention is a cross-sectional view of a pressure-controlled container according to one embodiment of the present invention.

[0026] In the figure: 1-tank body, 2-cover plate, 3-steel chisel, 4-steel chisel driving device, 11-first water outlet, 12-second water outlet, 21-air inlet, 22-air outlet, 23-water inlet. DETAILED DESCRIPTION

[0027] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0029] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0031] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the embodiments of the present invention belong. If the definitions set forth in this section are contrary to or otherwise inconsistent with the definitions set forth in the patents, patent applications, published patent applications, and other publications incorporated herein by reference, the definitions listed in this section take precedence over the definitions incorporated herein by reference.

[0032] In addition, the mass of the relevant components mentioned in the description of the embodiments of the present invention can not only refer to the specific content of each component, but also represent the proportional relationship between the masses of the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the description of the embodiments of the present invention, it is within the scope disclosed in the description of the embodiments of the present invention. Specifically, the mass described in the description of the embodiments of the present invention can be a mass unit known in the chemical industry such as μg, mg, g, kg, etc.

[0033] In some embodiments of the present invention, the method for slag heating comprises the following steps:

[0034] The steel slag is loaded into a pressure hot stuffy tank, which is sealed, and water is added to the pressure hot stuffy tank for heat stuffing treatment. During the process of adding water, the water level in the pressure hot stuffy tank is monitored by a water level sensor arranged in the pressure hot stuffy tank. When the threshold water level is reached, part of the water in the pressure hot stuffy tank is discharged in a linked manner, so that the water level in the pressure hot stuffy tank is below the threshold water level and the drainage channel is closed in a linked manner at the same time. The water in the pressure hot stuffy tank contacts the steel slag in a high temperature state and is heated, thereby forming water vapor, and the pressure in the pressure hot stuffy tank increases accordingly. A pressure sensor is pre-arranged in the pressure hot stuffy tank. When the pressure in the pressure hot stuffy tank reaches the pressure threshold, part of the gas in the pressure hot stuffy tank is discharged, so that the air pressure in the pressure hot stuffy tank is restored to below the pressure threshold and the exhaust pressure relief channel is closed in a linked manner.

[0035] When the pressure in the autoclave reaches the target pressure value and the temperature reaches the target temperature range, use a steel bar to make a hole in the steel slag in the autoclave from the side in the horizontal direction, and then pull out the steel bar. The principle of the above steps is that in the process of adding water to the autoclave, the steel slag at the top that first contacts the water undergoes phase change, physical change and chemical change, and the top layer of steel slag rapidly cools down from a solid or liquid state and transforms into small crushed particles. At the same time, the heated water or saturated water vapor in the upper layer continues to penetrate into the next layer of solid or liquid steel slag, and phase change, physical change and chemical change continue to occur. From a macroscopic perspective, the crushing process is carried out from top to bottom, but because of the penetration speed of water or steam, the shape of the steel slag and uneven heating, the depth and degree of pulverization at different locations in the same horizontal plane are not the same. Therefore, at a certain Under temperature and pressure conditions, a steel drill is used to perform horizontal jacking operations on the steel slag. After the horizontal jacking treatment, steel drill holes will be formed in the steel slag that has not been pulverized. The steel drill holes will allow water and steam to quickly penetrate in the horizontal plane, thereby actively intervening in the pulverization process at different positions along the gravity direction and reducing the pulverization difference along the gravity direction. The difference will change according to the density of the steel drill holes. The higher the density of the steel drill holes, the smaller the difference. While reducing the differentiation difference, the corresponding steel slag differentiation effect is improved, effectively avoiding the problem of uneven pulverization particle size after the steel slag is hot and stuffy.

[0036] Within the target pressure range, the heat-stifling treatment is completed when the temperature of the slag does not exceed 65°C and is maintained at 65°C for 2-2.5 hours. At this time, stop adding water, venting and relieving pressure, and fill nitrogen into the pressurized heat-stifling tank.

[0037] When the difference between the pressure in the pressurized hot tank and the atmospheric pressure is 0MPa and there is no water mist in the exhaust gas, the tank is opened and the slag is discharged.

[0038] In the above embodiments, during the hot stuffing treatment of the steel slag, a steel chisel is used to perform horizontal hole opening treatment on the steel slag, thereby providing a horizontal flow channel for water or steam, improving the uniformity of pulverization of the steel slag in the horizontal direction, and avoiding the problem of uneven pulverization due to uneven pulverization of the steel slag in the horizontal direction, which causes local cooling to be too fast, resulting in the inability of the local steel slag to react with water at an appropriate temperature in time.

[0039] In some embodiments, during the hot stuffing treatment of steel slag, water can be added to the pressurized hot stuffing tank continuously or discontinuously by controlling the temperature and pressure in the pressurized hot stuffing tank within the target range, wherein the discontinuous water addition can be intermittent water addition at equal intervals or intermittent water addition at unequal intervals.

[0040] In some embodiments, water is added by direct flow, spraying or atomization. The more uniformly the water added to the pressurized tank contacts the steel slag at different positions, the better the corresponding steel slag pulverization uniformity.

[0041] In some embodiments, water is added by spraying water into the pressurized hot pot through a plurality of nozzles arranged in a uniform array.

[0042] In some embodiments, the target pressure value is 0.2-0.25 MPa, and the target temperature range is 750-1000°C.

[0043] In the above embodiments, when the pressure value is set at 0.2-0.25MPa, the tank body with the autoclave is relatively safe, and the water vapor in the tank body can be kept in a supersaturated state, which is conducive to quickly penetrating into the gaps of the steel slag for reaction. When the temperature is 750-1000°C, the shrinkage rate of the steel slag is relatively large, and within this temperature range, the shrinkage rate of the steel slag is linearly related to the temperature. At this time, the steel bar is easily inserted into the steel slag, and the insertion process can be assisted in crushing. The steel bar hole formed after insertion is conducive to maintaining a stable shape. Within the range of 750-1000°C, the shrinkage rate of the steel slag is still relatively large. At this time, the water or water vapor entering can still produce a good reaction effect on the steel slag.

[0044] In some embodiments, the step of using a steel chisel to insert a hole into the steel slag in the autoclave from the side along the horizontal direction specifically includes the following steps:

[0045] When the temperature in the autoclave reaches the upper limit of the target temperature range, at least one steel bar is inserted into at least one side of the steel slag in the horizontal direction 100-200mm below the top of the steel slag; when the temperature in the autoclave reaches the median value of the target temperature range, at least one steel bar is inserted into at least one side of the steel slag in the horizontal direction at the middle position of the steel slag in the vertical direction; when the temperature in the autoclave reaches the lower limit of the target temperature range, at least one steel bar is inserted into at least one side of the steel slag in the horizontal direction 100-200mm above the bottom of the steel slag.

[0046] In the above embodiments, the pulverization process of steel slag under the action of water is gradually carried out from the top of the steel slag downward. In order to make the intervention process of the steel drill hole as gentle as possible and avoid the danger of explosion caused by the rapid contact of water with the high-temperature steel slag, a top-down program hole operation mode is adopted. Specifically, when water contacts the top of the steel slag, the temperature in the autoclave is generally high, and the steel slag located in the middle and bottom cannot directly contact the water. Therefore, relative to the steel slag at the top, the temperature is higher. At this time, only the steel slag at the top is processed by the steel drill hole, firstly reducing the uneven pulverization of the top steel slag. In the process of the pulverization process gradually proceeding from top to bottom, due to radiation heat dissipation or contact heat dissipation, the middle steel slag and the bottom steel slag are gradually cooled. When the temperature sensor located in the autoclave detects that the internal temperature is reduced to the median of the target temperature, the steel slag in the middle is processed by the hole to reduce the uneven pulverization of the steel slag in the middle. According to this rule, when the lower limit of the target temperature is reached, the steel slag at the bottom is processed by the hole.

[0047] In the above embodiments, it should be understood that the number of times of multiple steel bar insertion treatments can be more than 3 times, or can be twice, and the positions of multiple steel bar insertion holes can be distributed at equal intervals or at unequal intervals. The process can be adaptively modified according to the different heat-stifling containers. After multiple top-down insertion treatments, the slag can be pulverized more evenly, and explosion accidents caused by rapid and large-area cooling can be effectively avoided.

[0048] In some embodiments, when a steel bar is used to insert a hole into the steel slag in the autoclave from the side along the horizontal direction, the steel bar is kept in the steel slag for 1-3 minutes and then the steel bar is pulled out.

[0049] In the above embodiments, during the insertion process of the steel drill, the insertion time can be prolonged to effectively improve the stability of the hole formed after the steel drill is inserted, thereby avoiding the collapse of the hole after the steel drill is pulled out when the hole is not finalized.

[0050] In some embodiments, the cross-section of the steel chisel is circular, and the diameter of the steel chisel is 4-6 cm.

[0051] In the above embodiments, the inner wall of the hole formed after the circular steel bar is inserted has the advantage of a smooth transition, which can avoid stress concentration on the inner wall surface of the hole, thereby improving the structural stability of the hole. During the insertion process, the steel bar needs to withstand the high temperature of the steel slag and overcome the resistance of the steel slag. Therefore, when the diameter of the steel bar is 4-6 cm, the insertion effect is relatively good, and the insertion process causes less damage to the steel bar. Secondly, affected by the particle size of the internal components of the steel slag, the 4-6 cm hole is easy to maintain structural stability.

[0052] In some embodiments, the volume of the autoclave is 10-15 m 3 When hot and stuffy treatment, the speed of adding water is 18-24m 3 / h.

[0053] The above embodiments are preferred implementations in which the autoclave adopts a columnar structure, and specifically, a prismatic structure or a cylindrical structure may be adopted.

[0054] One embodiment of the pressure-heating tank of the present invention has a structure as follows: Figure 1 As shown, it includes: a tank body 1, a cover plate 2, a steel drill 3 and a steel drill driving device 4. The top opening of the tank body 1 is set, and the cover plate 2 is movably installed at the top opening of the tank body 1. The cover plate 2 selectively seals the top opening of the tank body 1. The side wall of the tank body 1 is opened with a plurality of steel drill holes in the horizontal reverse direction. A steel drill 3 is embedded in each steel drill hole. The steel drill 3 is dynamically sealed with the inner wall of the steel drill hole. The steel drill driving device 4 is arranged on the outside of the tank body 1. The steel drill driving device 4 is used to drive the steel drill 3 to reciprocate along the opening direction of the steel drill hole. The surface of the cover plate 2 is opened with an air inlet 21, an air outlet 22 and a water inlet 23. The side of the tank body 1 is opened with a first water outlet 11, and the bottom of the tank body 1 is opened with a second water outlet 12.

[0055] In the above embodiments, the tank body 1 and the cover plate 2 are combined to form a closed cavity structure. After the steel slag is loaded into the tank body 1, water is added to the tank body 1 through the water inlet 23 on the cover plate 2, thereby achieving heat-stifling treatment of the steel slag. It should be understood that valves are provided at the openings of the first water outlet 11, the second water outlet 12, the air inlet 21, the air outlet 22 and the water inlet 23, and the valves are connected to necessary peripheral units through pipelines, thereby achieving gas supply, water supply, water collection or gas collection.

[0056] In the above embodiments, the steel drill driving device 4 is used to drive the steel drill 3 to perform reciprocating motion in the steel drill hole, so as to realize the jacking treatment of the steel slag. The steel drill driving device 4 can adopt an existing structure with reciprocating driving capability. As an exemplary example, the steel drill driving device 4 can be a driving cylinder. The steel drill driving device 4 is fixed relative to the tank body 1. As an exemplary example, the steel drill driving device 4 can be installed on the outer surface of the tank body 1, or be kept relatively fixed with the tank body 1 through at least one intermediate connecting member.

[0057] In the above embodiments, the steel drill 3 is slidably arranged in the steel drill hole, and at the same time, a dynamic seal is formed between the steel drill 3 and the steel drill hole. As a demonstration example, a high temperature and high pressure resistant sealing ring is embedded in the steel drill hole, and the steel drill 3 is embedded in the sealing ring, thereby realizing a dynamic sealing connection between the steel drill 3 and the steel drill hole.

[0058] In some embodiments, a plurality of nozzles are disposed on a side of the cover plate 2 close to the opening of the tank body 1 , and the nozzles are connected to the water inlet 23 .

[0059] In the above embodiments, a plurality of nozzles spray the water discharged from the water inlet 23 into the tank body 1, so that the contact between the water and the slag is more uniform, the risk of explosion is reduced, and the uniformity of pulverization is improved.

[0060] In some embodiments, the number of the second water outlets 12 is not less than two, and the plurality of second water outlets 12 are arranged in an array along the circumference of the tank body 1 at the bottom of the tank body 1 .

[0061] In the above embodiments, water is pulverized from the top of the slag through a series of reactions and penetrates into the bottom slag through the gaps generated by the pulverization, and is finally discharged from the second water outlet 12. Since the pressure in the autoclave is relatively high during the heat-stifling process, water and steam have a tendency to enter the second water outlet 12 and be discharged from the shortest path under the action of pressure. At this time, if the number of the second water outlet 12 is one, the discharge path of water and steam will cause the slag far away from the path to be unable to make good contact with the water and steam. In order to avoid this problem, a plurality of second water outlets 12 are provided and the plurality of second water outlets 12 are evenly distributed, so that the discharge paths of water and steam are evenly distributed, which is beneficial to improving the uniformity of the contact between the slag and water at each position.

[0062] In some embodiments, during the heat treatment in the pressurized hot stuffy tank, water can be added intermittently or continuously. If added continuously, the water in the pressurized hot stuffy tank will exceed its capacity limit, so the water in the pressurized hot stuffy tank needs to be discharged. Optionally, the first water outlet 11 and / or the second water outlet 12 can be opened to discharge the water in the pressurized hot stuffy tank.

[0063] In some embodiments, at least three layers of steel drill holes are formed on the side of the tank body 1 at equal intervals along the vertical direction.

[0064] In the above embodiments, the vertical direction can also be understood as the direction of gravity. The three layers of steel drill holes have different heights, and the vertical distance between the steel drill holes of two adjacent layers is the same. In other feasible embodiments, the distance may also be different. By setting multiple layers of steel drill holes, the steel drill 3 can be inserted at different heights under different temperature conditions.

[0065] In some embodiments, the number of steel drill holes in each layer is not less than two, and the multiple steel drill holes in each layer are arranged in an array with equal spacing along the circumference of the tank body.

[0066] In the above embodiments, multiple steel chisels 3 are arranged in the same horizontal plane for insertion processing, so that the steel slag can form more horizontal channels in the horizontal plane. When there are more channels, the contact efficiency of water and steam on the steel slag is higher, and the pulverization treatment effect is better.

[0067] In some embodiments, different sensors are provided inside or on the surface of the autoclave, including pressure sensors, temperature sensors, liquid level sensors, etc. The sensors are connected to the external control unit by signal, and the external control unit is connected to the different valve structure signals on the autoclave. Different valves are controlled in linkage through a control program preset in the external control unit.

[0068] The advantages of the method for slag heating and stuffing of the present invention are described in detail below with reference to specific embodiments:

[0069] Example 1

[0070] In a pressure-heated tank with a diameter of 4m and a height of 1m, steel slag with a height of 0.5m is placed. The steel slag is in liquid state and has a temperature of 1460°C. Four cylindrical steel chisels 3 are arranged at a level 10cm below the steel slag liquid surface, four cylindrical steel chisels 3 are arranged at a level 0.25m below the steel slag liquid surface, and four cylindrical steel chisels 3 are arranged at a level 40cm below the steel slag liquid surface. The diameters of the steel chisels used above are all 4cm. After the pressure-heated tank is sealed, water is sprayed into the pressure-heated tank through the water inlet 23. The water inlet flow rate is 18m 3 / h, maintain the pressure in the autoclave at 0.2MPa, when the pressure exceeds 0.2MPa, open the air outlet 22 to release the pressure, maintain the water level in the autoclave at 30cm above the slag, when it exceeds the liquid level, open the first water outlet 11 to drain the water, when the temperature in the autoclave drops to 1000℃, drive 4 steel chisels 3 set at a horizontal plane 10cm below the slag liquid surface to be inserted into the slag, the insertion depth is 1.5m, the insertion holding time is 1min, then pull out the 4 steel chisels 3, continue to add water and maintain the pressure for hot stuffiness treatment, when the temperature drops to 875℃, drive 4 steel chisels 3 set at a horizontal plane 0.25m below the slag liquid surface to be inserted into the slag, the insertion depth is 1 .5m, the insertion time is 1min, then the 4 steel bar 3 is pulled out, water is continued to be added and the pressure is maintained for hot stuffy treatment. When the temperature drops to 750℃, 4 steel bar 3 set at a horizontal plane 40cm below the slag liquid level are driven to be inserted into the slag, the insertion depth is 1.5m, the insertion time is 1min, then the 4 steel bar is pulled out, water is continued to be added and the pressure is maintained for hot stuffy treatment. The timing starts after the temperature in the pressurized hot stuffy tank drops to 65℃. After 2h, the water inlet and exhaust pressure relief are closed, and nitrogen is introduced into the pressurized hot stuffy tank at the same time. The air outlet is observed. When the difference between the pressure in the pressurized hot stuffy tank and the atmospheric pressure is 0MPa, and there is no water mist condensed from water vapor at the air outlet, the cover plate 2 is opened for slag removal treatment.

[0071] Example 2

[0072] In a pressure-heated tank with a diameter of 4m and a height of 1m, steel slag with a height of 0.6m is placed. The steel slag is in liquid state and has a temperature of 1460°C. Four cylindrical steel chisels 3 are arranged at a level 20cm below the steel slag liquid surface, four cylindrical steel chisels 3 are arranged at a level 0.3m below the steel slag liquid surface, and four cylindrical steel chisels 3 are arranged at a level 40cm below the steel slag liquid surface. The diameters of the steel chisels used above are all 6cm. After the pressure-heated tank is sealed, water is sprayed into the pressure-heated tank through the water inlet 23. The water inlet flow rate is 24m 3 / h, maintain the pressure in the autoclave at 0.25MPa, when the pressure exceeds 0.25MPa, open the air outlet 22 to release the pressure, maintain the water level in the autoclave at 30cm above the slag, when it exceeds the liquid level, open the first water outlet 11 to drain the water, when the temperature in the autoclave drops to 1000℃, drive 4 steel chisels 3 set at a horizontal plane 20cm below the slag liquid surface to be inserted into the slag, the insertion depth is 1.5m, the insertion time is 1min, then pull out the 4 steel chisels 3, continue to add water and maintain the pressure for hot stuffiness treatment, when the temperature drops to 875℃, drive 4 steel chisels 3 set at a horizontal plane 0.3m below the slag liquid surface to be inserted into the slag, the insertion depth is 1. 5m, the insertion time is 1min, then pull out the 4 steel bar 3, continue to add water and maintain the pressure for hot stuffing treatment, when the temperature drops to 750℃, drive the 4 steel bar 3 set at the horizontal plane 40cm below the slag liquid surface to insert into the slag, the insertion depth is 1.5m, the insertion time is 1min, then pull out the 4 steel bar, continue to add water and maintain the pressure for hot stuffing treatment, and start timing after the temperature in the pressurized hot stuffy tank drops to 65℃. After 2.5h, close the water inlet and exhaust pressure relief, and at the same time, introduce nitrogen into the pressurized hot stuffy tank, observe the outlet, and when the difference between the pressure in the pressurized hot stuffy tank and the atmospheric pressure is 0MPa, and there is no water mist condensed by water vapor at the outlet, open the cover plate 2 and carry out slag treatment.

[0073] Comparative Example

[0074] In a 4m diameter and 1m high autoclave, 0.5m high steel slag is placed. The steel slag is liquid and has a temperature of 1460°C. After the autoclave is sealed, water is sprayed into the autoclave through the water inlet 23. The water flow rate is 18m 3 / h, maintain the pressure in the pressure tank at 0.2MPa. When the pressure exceeds 0.2MPa, open the air outlet 22 for pressure relief, maintain the water level in the pressure tank at 30cm above the slag. When it exceeds the liquid level, open the first water outlet 11 to drain water, maintain the pressure for hot stuffy treatment, and start timing after the temperature in the pressure tank drops to 65℃. After 2h, close the water inlet and exhaust to relieve the pressure, and at the same time, introduce nitrogen into the pressure tank, observe the air outlet, and when the difference between the pressure in the pressure tank and the atmospheric pressure is 0MPa, and there is no water mist condensed by water vapor at the air outlet, open the cover plate 2 and carry out slag treatment.

[0075] The particle size distribution and screening statistics of the slags of the above-mentioned Example 1, Example 2 and the comparative example were respectively carried out, and the obtained grading results are shown in the following table:

[0076]

[0077] The slag particles obtained by the steel slag hot stuffing method of the present invention have a more concentrated particle size distribution, a smaller proportion of large particles with poor crushing effect, and a higher proportion of particles with a reasonable size of 10-1 mm.

[0078] Example 3

[0079] In a pressure-heated tank with a diameter of 4m and a height of 1m, steel slag with a height of 0.5m is placed. The steel slag is in liquid state and has a temperature of 1460°C. Four cylindrical steel chisels 3 are arranged at a level 10cm below the steel slag liquid surface, four cylindrical steel chisels 3 are arranged at a level 0.25m below the steel slag liquid surface, and four cylindrical steel chisels 3 are arranged at a level 40cm below the steel slag liquid surface. The diameters of the steel chisels used above are all 2cm. After the pressure-heated tank is sealed, water is sprayed into the pressure-heated tank through the water inlet 23. The water inlet flow rate is 18m 3 / h, maintain the pressure in the autoclave at 0.2MPa, when the pressure exceeds 0.2MPa, open the air outlet 22 to release the pressure, maintain the water level in the autoclave at 30cm above the slag, when it exceeds the liquid level, open the first water outlet 11 to drain the water, when the temperature in the autoclave drops to 1000℃, drive 4 steel chisels 3 set at a horizontal plane 10cm below the slag liquid surface to be inserted into the slag, the insertion depth is 1.5m, the insertion holding time is 1min, then pull out the 4 steel chisels 3, continue to add water and maintain the pressure for hot stuffiness treatment, when the temperature drops to 875℃, drive 4 steel chisels 3 set at a horizontal plane 0.25m below the slag liquid surface to be inserted into the slag, the insertion depth is 1 .5m, the insertion time is 1min, then the 4 steel bar 3 is pulled out, water is continued to be added and the pressure is maintained for hot stuffy treatment. When the temperature drops to 750℃, 4 steel bar 3 set at a horizontal plane 40cm below the slag liquid level are driven to be inserted into the slag, the insertion depth is 1.5m, the insertion time is 1min, then the 4 steel bar is pulled out, water is continued to be added and the pressure is maintained for hot stuffy treatment. The timing starts after the temperature in the pressurized hot stuffy tank drops to 65℃. After 2h, the water inlet and exhaust pressure relief are closed, and nitrogen is introduced into the pressurized hot stuffy tank at the same time. The air outlet is observed. When the difference between the pressure in the pressurized hot stuffy tank and the atmospheric pressure is 0MPa, and there is no water mist condensed from water vapor at the air outlet, the cover plate 2 is opened for slag removal treatment.

[0080] Example 4

[0081] In a pressure-heated tank with a diameter of 4m and a height of 1m, steel slag with a height of 0.5m is placed. The steel slag is in liquid state and has a temperature of 1460°C. Four quadrangular steel chisels 3 are arranged at a level 10cm below the steel slag liquid surface, four quadrangular steel chisels 3 are arranged at a level 0.25m below the steel slag liquid surface, and four quadrangular steel chisels 3 are arranged at a level 40cm below the steel slag liquid surface. The length and width of the cross-section of the steel chisels used above are both 4cm. After the pressure-heated tank is sealed, water is sprayed into the pressure-heated tank through the water inlet 23. The water inlet flow rate is 18m 3 / h, maintain the pressure in the autoclave at 0.2MPa, when the pressure exceeds 0.2MPa, open the air outlet 22 to release the pressure, maintain the water level in the autoclave at 30cm above the slag, when it exceeds the liquid level, open the first water outlet 11 to drain the water, when the temperature in the autoclave drops to 1000℃, drive 4 steel chisels 3 set at a horizontal plane 10cm below the slag liquid surface to be inserted into the slag, the insertion depth is 1.5m, the insertion holding time is 1min, then pull out the 4 steel chisels 3, continue to add water and maintain the pressure for hot stuffiness treatment, when the temperature drops to 875℃, drive 4 steel chisels 3 set at a horizontal plane 0.25m below the slag liquid surface to be inserted into the slag, the insertion depth is 1 .5m, the insertion time is 1min, then the 4 steel bar 3 is pulled out, water is continued to be added and the pressure is maintained for hot stuffy treatment. When the temperature drops to 750℃, 4 steel bar 3 set at a horizontal plane 40cm below the slag liquid level are driven to be inserted into the slag, the insertion depth is 1.5m, the insertion time is 1min, then the 4 steel bar is pulled out, water is continued to be added and the pressure is maintained for hot stuffy treatment. The timing starts after the temperature in the pressurized hot stuffy tank drops to 65℃. After 2h, the water inlet and exhaust pressure relief are closed, and nitrogen is introduced into the pressurized hot stuffy tank at the same time. The air outlet is observed. When the difference between the pressure in the pressurized hot stuffy tank and the atmospheric pressure is 0MPa, and there is no water mist condensed from water vapor at the air outlet, the cover plate 2 is opened for slag removal treatment.

[0082] The slags of the above-mentioned embodiment 3 and embodiment 4 were respectively subjected to particle distribution screening statistics, and the obtained grading results are shown in the following table:

[0083]

[0084] It can be seen that although the same insertion process is used, when the size or shape of the steel chisel used for the insertion changes, it will still have a great impact on the particle distribution of the final slag. When a cylindrical steel chisel with a diameter of 4-6 cm is used, the heat-stifling effect is better.

[0085] Example 5

[0086] In a pressure-heated tank with a diameter of 4m and a height of 1m, steel slag with a height of 0.5m is placed. The steel slag is in liquid state and has a temperature of 1460°C. Four cylindrical steel chisels 3 are arranged at a level 10cm below the steel slag liquid surface, four cylindrical steel chisels 3 are arranged at a level 0.25m below the steel slag liquid surface, and four cylindrical steel chisels 3 are arranged at a level 40cm below the steel slag liquid surface. The diameters of the steel chisels used above are all 4cm. After the pressure-heated tank is sealed, water is sprayed into the pressure-heated tank through the water inlet 23. The water inlet flow rate is 18m 3 / h, maintain the pressure in the autoclave at 0.2MPa, when the pressure exceeds 0.2MPa, open the air outlet 22 to release the pressure, maintain the water level in the autoclave at 30cm above the slag, when it exceeds the liquid level, open the first water outlet 11 to drain the water, when the temperature in the autoclave drops to 750℃, drive 4 steel chisels 3 set at a horizontal plane 10cm below the slag liquid surface to be inserted into the slag, the insertion depth is 1.5m, the insertion time is 1min, then pull out the 4 steel chisels 3, continue to add water and maintain the pressure for hot stuffiness treatment, when the temperature drops to 625℃, drive 4 steel chisels 3 set at a horizontal plane 0.25m below the slag liquid surface to be inserted into the slag, the insertion depth is 1. 5m, the insertion time is 1min, then pull out the 4 steel bar 3, continue to add water and maintain the pressure for hot stuffing treatment, when the temperature drops to 500℃, drive the 4 steel bar 3 set at the horizontal plane 40cm below the slag liquid surface to insert into the slag, the insertion depth is 1.5m, the insertion time is 1min, then pull out the 4 steel bar, continue to add water and maintain the pressure for hot stuffing treatment, and start timing after the temperature in the pressurized hot stuffing tank drops to 65℃. After 2h, close the water inlet and exhaust pressure relief, and at the same time, introduce nitrogen into the pressurized hot stuffing tank, observe the outlet, and when the difference between the pressure in the pressurized hot stuffing tank and the atmospheric pressure is 0MPa, and there is no water mist condensed by water vapor at the outlet, open the cover plate 2 and carry out slag treatment.

[0087] Example 6

[0088] In a pressure-heated tank with a diameter of 4m and a height of 1m, steel slag with a height of 0.5m is placed. The steel slag is in liquid state and has a temperature of 1460°C. Four cylindrical steel chisels 3 are arranged at a level 10cm below the steel slag liquid surface, four cylindrical steel chisels 3 are arranged at a level 0.25m below the steel slag liquid surface, and four cylindrical steel chisels 3 are arranged at a level 40cm below the steel slag liquid surface. The diameters of the steel chisels used above are all 4cm. After the pressure-heated tank is sealed, water is sprayed into the pressure-heated tank through the water inlet 23. The water inlet flow rate is 18m 3 / h, maintain the pressure in the autoclave at 0.2MPa, when the pressure exceeds 0.2MPa, open the air outlet 22 to release the pressure, maintain the water level in the autoclave at 30cm above the slag, when it exceeds the liquid level, open the first water outlet 11 to drain the water, when the temperature in the autoclave drops to 1200℃, drive 4 steel chisels 3 set at a horizontal plane 10cm below the slag liquid surface to be inserted into the slag, the insertion depth is 1.5m, the insertion holding time is 1min, then pull out the 4 steel chisels 3, continue to add water and maintain the pressure for hot stuffiness treatment, when the temperature drops to 1100℃, drive 4 steel chisels 3 set at a horizontal plane 0.25m below the slag liquid surface to be inserted into the slag, the insertion depth is 1 .5m, the insertion time is 1min, then the 4 steel bar 3 is pulled out, water is continued to be added and the pressure is maintained for hot stuffy treatment. When the temperature drops to 1000℃, 4 steel bar 3 set at the horizontal plane 40cm below the slag liquid level are driven to be inserted into the slag, the insertion depth is 1.5m, the insertion time is 1min, then the 4 steel bar is pulled out, water is continued to be added and the pressure is maintained for hot stuffy treatment. The timing starts after the temperature in the pressurized hot stuffy tank drops to 65℃. After 2h, the water inlet and exhaust pressure relief are closed, and nitrogen is introduced into the pressurized hot stuffy tank at the same time. The outlet is observed until the difference between the pressure in the pressurized hot stuffy tank and the atmospheric pressure is 0MPa, and there is no water mist condensed from water vapor at the outlet, then the cover plate 2 is opened for slag removal treatment.

[0089] The slags of the above-mentioned embodiment 5 and embodiment 6 were respectively subjected to particle distribution screening statistics, and the obtained grading results are shown in the following table:

[0090]

[0091] It can be seen that although the same plug-in process is used, when the program temperature of the plug-in is too high, the large particles and powder in the slag increase significantly. At the same time, during the hot stuffing process, a bursting sound can be clearly heard in the pressure hot stuffing tank. When the temperature of the plug-in is low, it has little effect on the pulverization effect of the slag, and there is no obvious effect of enhancing pulverization and improving differentiation uniformity.

[0092] 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 in the protection scope of the present invention.

Claims

1. A method for smoldering steel slag, characterized in that: The method comprises the following steps: Step 1: put the steel slag into a pressure-heating tank, seal the pressure-heating tank, and add water into the pressure-heating tank for heat-stifling treatment; Step 2, when the pressure in the autoclave reaches the target pressure value and the temperature is within the target temperature range: when the temperature in the autoclave reaches the upper limit of the target temperature range, insert at least one steel bar into at least one side of the steel slag in the horizontal direction 100-200mm below the top of the steel slag; when the temperature in the autoclave reaches the median value of the target temperature range, insert at least one steel bar into at least one side of the steel slag in the horizontal direction at the middle position of the steel slag in the vertical direction; when the temperature in the autoclave reaches the lower limit of the target temperature range, insert at least one steel bar into at least one side of the steel slag in the horizontal direction 100-200mm above the bottom of the steel slag, keep the steel bar in the steel slag for 1-3 minutes, and then pull out the steel bar; Step 3: within the target pressure range, heat and stuff until the temperature of the steel slag in the pressurized hot stuffing tank does not exceed 65°C, and the time of not exceeding 65°C reaches 2-2.5h, the heat and stuffing is completed, and the water addition and exhaust pressure relief are stopped, and nitrogen is filled into the pressurized hot stuffing tank at the same time; Step 4: When the difference between the pressure in the pressurized hot tank and the atmospheric pressure is 0 MPa and there is no water mist in the exhaust gas, open the tank and discharge the slag; The target pressure value is 0.2-0.25 MPa, and the target temperature range is 750-1000°C.

2. The method for smoldering steel slag according to claim 1, characterized in that: The cross section of the steel chisel is circular, and the diameter of the steel chisel is 4-6 cm.

3. The method for smoldering steel slag according to claim 1, characterized in that: The volume of the autoclave is 10-15m 3 When hot and stuffy treatment, the water adding speed is 18-24m 3 / h.

4. The method for hot stuffing of steel slag as claimed in any one of claims 1 to 3 uses a pressure hot stuffing pot, characterized in that: It includes a tank body, a cover plate, a steel drill and a steel drill driving device. The top of the tank body is open, the cover plate is movably installed at the top opening of the tank body, the cover plate selectively seals the top opening of the tank body, a plurality of steel drill holes are opened in the horizontal direction on the side wall of the tank body, a steel drill is embedded in each steel drill hole, the steel drill is dynamically sealed with the inner wall of the steel drill hole, the steel drill driving device is arranged on the outside of the tank body, the steel drill driving device drives the steel drill to reciprocate along the opening direction of the steel drill hole, an air inlet, an air outlet and a water inlet are opened on the surface of the cover plate, a first water outlet is opened on the side of the tank body, and a second water outlet is opened on the bottom of the tank body.

5. The pressurized hot pot as claimed in claim 4, characterized in that: The number of the second water outlets is not less than two, and the plurality of second water outlets are arranged in an array along the circumference of the tank body at the bottom of the tank body.

6. The pressurized hot pot as claimed in claim 4, characterized in that: At least three layers of steel drill holes are opened at equal intervals on the side of the tank body in the vertical direction, and the number of steel drill holes in each layer is not less than one.

7. The pressurized hot pot according to claim 6, characterized in that: The number of steel drill holes in each layer is not less than two, and the multiple steel drill holes in each layer are arranged in an array with equal intervals along the circumference of the tank body.

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