WO2019161697A1 - Liquid-state slag dry-type centrifugal granulation slag particles quality regulating method - Google Patents

Abstract

Disclosed is a liquid-state slag dry-type centrifugal granulation slag particle quality regulating method. The vitreous conversion rate of slag particles, the particle size and distribution of the slag particles, and the activity of the slag particles are regulated; moreover, a liquid-state slag dry-type centrifugal granulation system is provided. The system consists of a granulator, a granulator fixing device, a shaft cooling air duct, an annular air duct, a rotating shaft, a motor, a sealing cover, and a fan, wherein the granulator fixing device is provided with a dendritic air opening, so that effects of air crushing and air quenching can be realized, and regulation of the vitreous conversion rate, and the particle size and distribution of the slag particles is facilitated. By means of the liquid-state slag dry-type centrifugal granulation slag particle quality regulating method provided by the present invention, the vitreous conversion rate of the granulated slag particles can be improved, and the particle size of the slag particles can be controlled, and the activity of the granulated slag particles is improved, so that the resource utilization of the granulated slag particles is improved, and reference is provided for industrial application of dry-type centrifugal granulation technology.

Description

Liquid slag dry centrifugal granulation slag particle quality control method Technical field

The invention relates to the technical field of waste heat recovery of high-temperature liquid slag, in particular to a method for controlling quality of dry granulated granulated slag of liquid slag.

Background technique

China is currently the world's largest steel producer. In 2016, China's pig iron production was about 701 million tons, accounting for about 60% of the world's total production. In the process of smelting pig iron, blast furnace slag containing huge heat was also produced. The blast furnace slag is generally discharged at a temperature between 1400 and 1550 ° C. Each ton of slag contains (1260 to 1880) × 10 ³ kJ of sensible heat, equivalent to 60 kg of standard coal. Under the existing ironmaking technology in China, for every ton of pig iron produced by the production of 0.3 tons of blast furnace slag, the current calculation of pig iron production in China is 701 million tons, which can be converted into blast furnace slag of about 210 million tons. About 12.618 million tons of standard coal.

The dry slag pit cooling method and the water slag slag method are the most common blast furnace slag treatment methods in China. The dry slag pit cooling method directly discharges the high-temperature liquid slag into the dry slag pit to be air-cooled, and assists water cooling. The method generates a large amount of water vapor when cooling, and releases a large amount of H ₂ S and SO ₂ gas, corrodes buildings, damages equipment, and deteriorates the working environment. Generally, the method is used only in accident handling. 90% of blast furnace slag in China is treated by water slag. The water slag method refers to the use of low-temperature cooling water to directly mix with high-temperature liquid slag, so that the liquid slag temperature is rapidly lowered and the glass body slag particles are formed. The water slag method can be divided into Inba method, Tula method, bottom filtration method, Lhasa method and Mintek method according to different process flow. Although the water slag slag process is constantly evolving, the core of the technology is to spray water quenching of high temperature liquid slag to achieve the purpose of cooling and granulation, and then slag separation, the slag water is recirculated through precipitation filtration. use. Although the vitreous slag produced by this method can be used in the cement industry for resource utilization, the process wastes a lot of water resources, generates harmful gases such as SO ₂ and H ₂ S, and cannot effectively recover the high temperature liquid slag. Quality waste heat resources.

The commonly used dry slag cooling method and water slag method not only waste all the high-quality waste heat resources contained in the high-temperature liquid slag, but also consume a lot of water resources and cause serious pollution to the environment. These treatment methods can no longer adapt to the current situation. The urgent need for energy saving and emission reduction in the steel industry. The dry centrifugal granulation method is widely favored due to its low energy consumption, small and uniform particle size, and high added value of products.

In the dry centrifugal granulation process, the liquid slag drops onto the surface of the high-speed rotating granulator, and is scooped out under the action of centrifugal force and friction force to form small droplets under the action of surface tension. These tiny liquids The droplets and the heat transfer medium in the space are subjected to forced convection heat exchange, and radiative heat exchange with the surrounding environment causes the temperature of the small droplets to decrease, and then a phase change occurs to form a solidified layer. As the temperature is further reduced, the droplets gradually transform into solid small particles. However, the current dry granulation technology cannot effectively control the quality of granulated slag particles during the slag granulation process, which affects the subsequent application value:

(1) If the conversion rate of the granulated granules discharged from the system is lower than a certain value, it is not conducive to its efficient resource utilization;

(2) If the particle size of the granulated slag is too large, the cooling rate of the molten slag particles decreases during the heat exchange between the space and the heat transfer medium, and the crystal phase transformation is easy, resulting in a decrease in the glass transition rate. High-efficiency resource utilization of granulated slag particles; if the particle size of the granulated slag particles is too small, on the one hand, it is easy to impinge on the wall surface of the granulation chamber in a molten state or in a molten state in the outer coagulation to adhere thereto, thereby causing granulation Over-temperature, corrosion, etc. on the wall surface of the silo, the large blocks that are bonded after cooling are not easy to clean, which brings great workload to the overhaul work; on the other hand, the particle size is too small, and it is easy to be blown by the cooling wind, if the cooling is reduced The air volume is not conducive to cooling. Therefore, the particle size needs to be controlled within a certain range.

(3) The improvement of the activity of the granulated slag particles helps to improve its resource utilization.

Therefore, in order to ensure the ultimate goal of liquid slag dry centrifugal granulation and waste heat recovery and resource utilization technology, it is urgent to provide a liquid slag dry centrifugal granulation slag quality control method.

Summary of the invention

The object of the present invention is to provide a method for controlling the quality of dry granulated granulated slag particles of liquid slag, ensuring high conversion rate of granulated granules, small particle size and good distribution, and good activity of slag particles, thereby improving efficient resource utilization thereof. Use value to provide a reference for industrial applications.

In order to achieve the above object, the technical solution adopted by the present invention is:

The method for controlling the quality of dry granulated granulated slag particles of liquid slag includes: the quality of the slag particles includes the vitreous conversion rate of the slag particles, the particle size and distribution of the slag particles, and the slag particle activity;

The method for controlling the quality of the dry granulated granulated slag particles of the liquid slag comprises:

(1) regulation of vitreous conversion of slag particles;

The glass slag conversion rate is related to the cooling rate. By rapid cooling, the slag particles rapidly cross the crystal phase transition region to realize the slag particle amorphous phase transition;

(2) Controlling the particle size and particle size distribution of the slag particles;

(3) Granulation slag particle activity:

The fineness of the granulated slag particles is reduced by a mechanical grinding method to activate the activity of the slag particles; or an activator is added to increase the activity of the slag particles.

Further, (1) regulation of vitreous conversion of slag particles:

The conversion rate of slag glass vitreous is related to its cooling rate. By rapid cooling, the slag particles can be quickly crossed across the crystal phase transition region to realize its amorphous phase transition.

The high-temperature granulated slag particles are rapidly cooled in the granulating chamber. Set the edge cooling air of the granulator, combine the flight trajectory of the granulated slag particles, match the cooling air flow field and momentum; set the film cooling air on the granulated water wall or the granulated warehouse wall, combined with the flight trajectory of the granulated slag particles, Matching the volume of the granulating bin and the wall temperature of the granulated water wall or the temperature and wind speed of the film cooling air on the wall of the granulated bin; strengthening the high temperature by setting the edge of the granulator cooling wind, the granulated water wall or the film cooling wind The radiant heat exchange and convective heat transfer between the granulated slag particles and the surrounding environment enable rapid cooling of the high temperature granulated slag particles.

In the moving bed or fluidized bed, a cold wall is arranged on the moving bed or the wall of the fluidized bed, and the cold wall adopts a membrane wall or a non-membrane wall, and the cooling wall or the cooling water is passed through the cold wall to realize the adhering layer and the cold layer. Wall solid-solid heat transfer; a buried pipe is arranged in the moving bed or the fluidized bed space, and the cooling pipe or the cooling water is passed through the buried pipe, and the buried pipe adopts a round pipe or a wear-resistant shaped pipe, and passes through the moving bed or the fluidized bed inner layer Solid-solid heat transfer with the wall of the buried pipe, control the cooling rate of the molten layer and the semi-melted layer inside the moving bed or the fluidized bed slag, realize the vitreous transformation of the slag particles; pass the cooling wind in the moving bed or the fluidized bed The convective heat transfer between the material layer and the cooling air realizes the glass body transformation of the slag particles. At the same time, a heating surface of the buried pipe is arranged between the moving bed and the granulating bin, and the cooling fluid is passed through the buried pipe, and the buried pipe adopts a round pipe or a wear-resistant shaped pipe.

Further, (2) particle size and particle size distribution regulation of the slag particles:

a temperature control unit for controlling the high temperature slag in the liquid slag buffer device to maintain the set temperature range, and controlling the outflow slag temperature of the buffer device to maintain the set temperature range;

a flow control unit for controlling the flow rate of the high-temperature slag flowing out of the buffer device in a set range to ensure the smoothness of the flow;

a granulator control unit for controlling the centering of the granulator center and the center of the slag tube of the buffer device, and ensuring smooth operation of the granulator during high-speed rotation;

First, through the temperature control unit, flow control unit and granulator control unit, control the temperature and flow rate of the liquid slag falling into the granulator, and ensure that the granulator and the slag tube are centered and smooth without shaking; then enter the commissioning Through the process test, adjusting the granulator rotation speed, outflow flow rate, viscosity temperature characteristics, granulator structure, granulator size, granulator surface roughness, granulator edge wind speed and angle, to obtain granulated slag particles Particle size and granulator rotation speed, outflow flow rate, viscosity temperature characteristics, granulator structure, granulator size, granulator surface roughness, granulator edge wind speed and angle;

When the process test is used to obtain the granulated particle size and granulator rotation speed, the outflow flow rate, the viscosity temperature characteristic, the granulator structure, the granulator size, the granulator surface roughness, the granulator edge wind speed and the angle After the relationship, the normal granulation process begins;

If the particle size of the granulated slag obtained according to the above particle size relationship is larger than the set interval during the normal granulation process (the set value refers to a set value or slightly fluctuates in the vicinity), fine granulation is fine-tuned. The rotation speed of the device is returned to the set interval; if the particle size of the granulated slag is smaller than the set interval, the rotation speed of the small granulator is finely adjusted to return to the set interval.

In the granulation process, if the particle size of the granulated slag is within the set interval, but the proportion of the granulated product is high, the granulator rotation speed, the outflow flow rate, the viscosity temperature characteristic, and the granulation can be appropriately adjusted. Surface roughness, granulator edge air volume and angle, etc., to achieve the goal of small particle size of granulated slag and low proportion of filaments.

Further, in the method for controlling the vitreous conversion rate of the slag particles, if the moving bed structure is adopted, it is considered that a scraper is arranged in the vicinity of the surface of the moving bed layer to periodically push or rotate the push layer to uniformly material, and the scraper has a strand. Cool the wind.

Further, the temperature control means of the temperature control unit includes: the cache device has a temperature control program, the cache device adopts a heat supplement method, the cache device has a temperature control program, and a heat supplement method is added.

Further, if the known viscosity-temperature characteristic of the slag cannot satisfy the requirement of controlling the particle size of the granulated slag, the particle size can be controlled by adjusting the alkalinity of the slag to adjust the viscosity-temperature characteristic of the slag.

Further, in the method for controlling the vitreous conversion rate of the slag particles, if it is ensured that each parameter (such as the granulated air volume, the moving bed cooling air volume, the moving bed layer height, etc.) is within a set value range, During the process of detecting, the vitreous conversion rate of the slag particles is detected. If the conversion rate is less than the set value, the process proceeds to step (a); if the conversion rate is greater than the set value, the process ends; and the vitreous conversion rate of the slag particles is continuously monitored;

(a) Confirm whether the liquid slag particle size is within the set interval. If it exceeds the set interval, adjust the slag particle size to the set range and transfer to step (b); if it does not exceed the set interval, directly turn Into step (b);

(b) Gradually increase the annular air volume at the edge of the granulator until the vitreous conversion rate of the granulated slag particles reaches the set value, and ends; if the annular air volume at the edge of the granulator increases to the maximum, the vitreous conversion rate of the granulated slag particles is still less than Set the value and go to step (c);

(c) If there is a film cooling wind on the wall of the granulated silo, gradually increase the amount of film cooling air on the wall of the granulated silo until the vitreous conversion rate of the granulated slag reaches the set value; The film cooling air volume is increased to the maximum on the wall of the chemical silo, and the glass body conversion rate of the granulated slag particles is still less than the set value, and is transferred to step (d); if there is no air film cooling wind on the granulated silo wall, Transfer to step (d);

(d) If a scraper cooling wind is provided near the surface of the moving bed layer, the amount of the scraper surface of the moving bed layer is increased until the vitreous conversion rate of the granulated slag particles reaches a set value, and ends; if the surface of the bed layer is moved The scraper cooling air volume set nearby is added to the maximum, and the vitreous conversion rate of the granulated slag particles is still less than the set value, and the process proceeds to step (e); if no scraper cooling wind is disposed near the surface of the moving bed layer, the transfer step is performed. (e);

(e) increasing the cooling air volume of the moving bed until the vitreous conversion rate of the granulated slag particles reaches the set value, and ends; if the moving bed cooling air volume is maximized, the vitreous conversion rate of the granulated slag particles is still less than the set value, and is transferred. Step (f);

(f) Adjust the operation according to the relationship between particle size and granulator rotation speed, outflow flow rate, viscosity-temperature characteristics, granulator structure, granulator size, granulator surface roughness, granulator edge wind volume and angle Parameters and slag physical properties to reduce the particle size of the slag until the vitreous conversion rate of the granulated slag particles reaches a set value; if the particle size of the slag particles is reduced to a limit value, the vitreous conversion rate of the granulated slag particles is still less than Set the value and go to step (g);

(g) Increasing the moving bed level until the vitreous conversion of the granulated granules reaches a set value.

Further, the liquid slag dry centrifugal granulation slag particle quality control method is applicable to a plurality of liquid slag dry centrifugal granulation and waste heat recovery systems, and a liquid slag dry centrifugal granulation system is proposed here;

A liquid slag dry centrifugal granulation system comprising: a granulator, a granulator fixing device and a granulator driving device; a granulator fixed on the granulator fixing device; and an air flow passage inside the granulator fixing device The granulator fixing device is arranged to contact the bottom of the granulator to provide an extended heating surface; the top of the granulator fixing device is provided with a plurality of first tuyères, and the outlet angle of the top first tuyere intersects with the dip angle of the edge of the granulator for The liquid film or liquid filament formed during the granulation process is externally broken; the granulator fixing device is provided with a plurality of second tuyères on the side, and the second tuyere is parallel or intersected with the inclination angle of the edge of the granulator for the granulation process. The droplets formed by the liquid filament breakage are cooled; the first tuyere and the second tuyere are in communication with the airflow passage; the granulator drive is used to drive the granulator to rotate.

Further, the invention further comprises a granulator driving device and a shaft cooling air duct; the granulator driving device comprises a motor and a rotating shaft; the output shaft of the motor is fixedly connected with the lower end of the rotating shaft; and the upper end of the rotating shaft is fixedly connected with the bottom of the granulator fixing device; a plurality of temperature-resistant blades are arranged on the rotating shaft; the shaft cooling air duct comprises a motor sealing cover, an inner sleeve of the air duct, a shaft sleeve and a rotating shaft; the sealing cover surrounds the outer circumference of the motor, and the sleeve and the shaft sleeve of the air duct are sleeved on the rotating shaft The outer circumference; the inner ring of the temperature-resistant thrust bearing and the temperature-resistant locating bearing are fixed on the rotating shaft, and the outer ring is fixed on the inner wall of the inner sleeve of the air duct; the outer sleeve of the shaft sleeve is fixed on the outer ring of the temperature-resistant bearing at the top thereof and the temperature-resistant bearing of the lower part thereof The temperature-resistant blades are surrounded by the outer ring; the temperature-resistant thrust bearing and the temperature-resistant locating bearing are provided with air flow passages; the sealing cover is fixedly connected with the inner sleeve of the air duct, and is connected through the vent; the inner sleeve of the air duct An outer sleeve of the air duct is arranged around the outer circumference of the cylinder, and an annular cooling air duct is formed between the inner sleeve of the air duct and the outer sleeve of the air duct, and a plurality of wind hoods are arranged annularly at the top of the annular cooling air duct; Cool the air duct inlet.

Further, the shaft cooling air enters from the air vent of the sealing cover, and after cooling the rotating shaft through the inside of the shaft sleeve, most of the air flow passages entering the granulator fixing device are uniformly distributed from the top of the granulator fixing device and the side walls. The first tuyere and the second tuyere enter the granulation chamber, and a small portion enters the granulation chamber from a narrow gap between the granulator fixture and the inner sleeve of the duct.

Further, the air outlet of the hood is lower than the air outlet of the first air outlet and the second air outlet.

Further, there are three ways to generate shaft cooling air:

In the first mode, the cooling air is generated by the fan, and enters from the air outlet of the sealing cover, most of which flows out through the air flow passage of the granulator fixing device, and a small portion flows out from the narrow gap between the fixing device and the inner sleeve of the air duct;

In the second mode, the temperature-resistant blades on the rotating shaft generate cooling air with the high-speed rotation of the rotating shaft, and most of the airflow passages passing through the granulator fixing device flow out, and a small portion flows out from a narrow gap between the fixing device and the inner sleeve of the air duct;

In the third mode, the fan air outlet and the high temperature rotating blade of the temperature resistant blade cooperate as the shaft cooling wind to cool the shaft cooling air duct and the rotating shaft.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The method for controlling the quality of dry granulated granulated slag particles of liquid slag provided by the invention can improve the glass body conversion rate of the granulated slag particles, effectively control the particle size of the slag particles, and improve the activity of the granulated slag particles, thereby improving The resource utilization of granulated slag particles provides a certain reference for industrial applications.

(2) The invention proposes a structure for ensuring the air outlet at the edge of the granulator, wherein a plurality of tuyères are opened at the top of the granulator fixing device, and the outlet angle intersects with the dip angle of the edge of the granulator, which can be used for the granulation process. The liquid film or liquid filament formed in the middle is crushed by external force to enhance the granulation effect, which is favorable for controlling the particle size of the granulated slag. The granulator fixing device is provided with a plurality of tuyères on the side thereof, and the tuyere is parallel or intersected with the inclination angle of the edge of the granulator, which can cool the droplets formed by the liquid filament breakage during the granulation process, thereby improving the vitreous conversion rate, which is beneficial to The slag glass vitreous conversion rate is controlled. At the same time, an annular wind channel is opened on the outer side, and an annular air outlet is arranged on the top, which can cool the slag particles formed by granulation, increase the conversion rate of the glass body, and control the conversion rate of the slag glass.

(3) The present invention proposes a liquid slag dry centrifugal granulation system in which small-temperature-resistant blades of one, two or more stages are arranged on the rotating shaft. During the granulation process, the rotating shaft drives the temperature-resistant blade to rotate at a high speed. On the one hand, the flow power of the air duct is generated, the crushing effect of the granulated edge wind is enhanced, and the cooling of the shaft cooling device to the shaft and the granulator fixing device is accelerated. On the other hand, the temperature-resistant blade can also be used as a rib structure to enhance the overall heat dissipation of the rotating shaft.

(4) The present invention proposes that in the method for controlling the vitreous conversion rate of the slag particles, it is conceivable to provide a squeegee near the surface of the moving bed layer to periodically push or rotate the push layer to uniformly material, and the squeegee has a cooling wind. It is used to cool the slag particles falling from the granulation bin into the surface of the moving bed layer, preventing the bonding, increasing the cooling rate and accelerating the glass transition.

DRAWINGS

The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

Figure 1 is a logic diagram for adjusting the glass transition rate of liquid slag dry centrifugal granulated slag particles;

2 is a logic diagram of particle size control of liquid slag dry centrifugal granulated slag particles;

Figure 3 is a schematic diagram of a liquid slag dry centrifugal granulation system;

Figure 4 is a schematic view of a granulator fixture.

209-motor; 210-sealing cover; 211-coupling; 216-outer sleeve; 217-duct in duct; 219-granulator; 220-hood; 222-shaft sleeve; 223-shaft; 224-temperature resistant blade; 225-annular air vent; 226-vent; 227-sealed hood tuyere; 232-granulator fixture; 233-airflow runner; 234-expanded heating surface; 235-second tuyer; - The first air outlet.

Detailed ways

Referring to Figures 1 to 4, the method for controlling the quality of the dry granulated granulated slag of the liquid slag according to the present invention comprises the glass transition rate of the slag particles, the particle size and distribution of the slag particles, and the slag particle activity;

(1) Method for controlling vitreous conversion rate of slag particles:

The conversion rate of slag glass vitreous is related to its cooling rate. By rapid cooling, the slag particles can be quickly crossed across the crystal phase transition region to realize its amorphous phase transition.

Rapid cooling of high-temperature granulated slag particles should be achieved in the granulation tank. Set the edge cooling air of the granulator, combine the flight trajectory of the granulated slag particles, match the cooling air flow field and momentum; set the film cooling air on the granulated water wall or the granulated warehouse wall, combined with the flight trajectory of the granulated slag particles, Matching the volume of the granulating bin and the wall temperature of the granulated water wall or the temperature and wind speed of the film cooling air on the wall of the granulated bin; strengthening the high temperature by setting the edge of the granulator cooling wind, the granulated water wall or the film cooling wind The radiant heat exchange and convective heat transfer between the granulated slag particles and the surrounding environment enable rapid cooling of the high temperature granulated slag particles.

In the moving bed or fluidized bed, a cold wall is arranged on the moving bed or the wall of the fluidized bed, and the cold wall adopts a membrane wall or a non-membrane wall, and the cooling wall or the cooling water is passed through the cold wall to realize the adhering layer and the cold layer. Wall solid-solid heat transfer; a buried pipe is arranged in the moving bed or the fluidized bed space, and the cooling pipe or the cooling water is passed through the buried pipe, and the buried pipe adopts a round pipe or a wear-resistant shaped pipe, and passes through the moving bed or the fluidized bed inner layer Solid-solid heat transfer with the wall of the buried pipe, control the cooling rate of the molten layer and the semi-melted layer inside the moving bed or the fluidized bed slag, realize the vitreous transformation of the slag particles; pass the cooling wind in the moving bed or the fluidized bed The convective heat transfer between the material layer and the cooling air realizes the glass body transformation of the slag particles. At the same time, a heating surface of the buried pipe is arranged between the moving bed and the granulating chamber, and the cooling pipe or the cooling water is passed through the buried pipe, and the buried pipe adopts a round pipe or a wear-resistant shaped pipe. If the moving bed structure is adopted, it is also conceivable to set a scraper plate near the surface of the moving bed layer to periodically push or rotate the push layer to evenly material, and the scraper plate has a cooling wind for cooling from the granulating bin to move. The slag particles on the surface of the bed layer prevent the bonding while increasing the cooling rate and accelerating the glass transition.

Taking the granulated silo and moving bed structure as an example, a method for controlling the vitreous conversion rate of slag particles is proposed:

If it is ensured that various parameters (such as granulated air volume, moving bed cooling air volume, moving bed layer height, etc.) are within the set value range, the glass transition rate of the slag particles is detected during the granulation process, if converted If the rate is less than the set value, proceed to step (a); if the conversion rate is greater than the set value, the end; continue to monitor the vitreous conversion rate of the slag particles;

(a) Confirm whether the liquid slag particle size is within the set interval. If it exceeds the set interval, adjust the slag particle size to the set range and transfer to step (b); if it does not exceed the set interval, directly turn Into step (b);

(b) Gradually increase the annular air volume at the edge of the granulator until the vitreous conversion rate of the granulated slag particles reaches the set value, and ends; if the annular air volume at the edge of the granulator increases to the maximum, the vitreous conversion rate of the granulated slag particles is still less than Set the value and go to step (c);

(c) If there is a film cooling wind on the wall of the granulated silo, gradually increase the amount of film cooling air on the wall of the granulated silo until the vitreous conversion rate of the granulated slag reaches the set value; The film cooling air volume is increased to the maximum on the wall of the chemical silo, and the glass body conversion rate of the granulated slag particles is still less than the set value, and is transferred to step (d); if there is no air film cooling wind on the granulated silo wall, Transfer to step (d);

(d) If a scraper cooling wind is provided near the surface of the moving bed layer, the amount of the scraper surface of the moving bed layer is increased until the vitreous conversion rate of the granulated slag particles reaches a set value, and ends; if the surface of the bed layer is moved The scraper cooling air volume set nearby is added to the maximum, and the vitreous conversion rate of the granulated slag particles is still less than the set value, and the process proceeds to step (e); if no scraper cooling wind is disposed near the surface of the moving bed layer, the transfer step is performed. (e);

(e) increasing the cooling air volume of the moving bed until the vitreous conversion rate of the granulated slag particles reaches the set value, and ends; if the moving bed cooling air volume is maximized, the vitreous conversion rate of the granulated slag particles is still less than the set value, and is transferred. Step (f);

(f) Adjust the operation according to the relationship between particle size and granulator rotation speed, outflow flow rate, viscosity-temperature characteristics, granulator structure, granulator size, granulator surface roughness, granulator edge wind volume and angle Parameters and slag physical properties to reduce the particle size of the slag until the vitreous conversion rate of the granulated slag particles reaches a set value; if the particle size of the slag particles is reduced to a limit value, the vitreous conversion rate of the granulated slag particles is still less than Set the value and go to step (g);

(g) Increasing the moving bed level until the vitreous conversion of the granulated granules reaches a set value.

(2) Regulation of particle size and particle size distribution of slag particles:

The temperature control unit is configured to control the high temperature slag in the liquid slag buffer device to maintain the set temperature range, and control the outflow slag temperature of the buffer device to maintain the set temperature range; the temperature control unit of the temperature control unit includes: a cache The device has its own temperature control program, the buffer device adopts the heat supplement method, the cache device has its own temperature control program and adds heat supplement means;

a flow control unit for controlling the flow rate of the high-temperature slag flowing out of the buffer device in a set range to ensure the smoothness of the flow;

a granulator control unit for controlling the centering of the granulator center and the center of the slag tube of the buffer device, and ensuring smooth operation of the granulator during high-speed rotation;

First, through the temperature control unit, flow control unit and granulator control unit, control the temperature and flow rate of the liquid slag falling into the granulator, and ensure that the granulator and the slag tube are centered and smooth without shaking; then enter the commissioning Through the process test, adjusting the granulator rotation speed, outflow flow rate, viscosity temperature characteristics, granulator structure, granulator size, granulator surface roughness, granulator edge wind speed and angle, to obtain granulated slag particles Particle size and granulator rotation speed, outflow flow rate, viscosity temperature characteristics, granulator structure, granulator size, granulator surface roughness, granulator edge wind speed and angle;

When the process test is used to obtain the granulated particle size and granulator rotation speed, the outflow flow rate, the viscosity temperature characteristic, the granulator structure, the granulator size, the granulator surface roughness, the granulator edge wind speed and the angle After the relationship, the normal granulation process begins;

If the particle size of the granulated slag obtained according to the above particle size relationship is larger than the set interval during the normal granulation process, the granule speed of the granulator is finely adjusted to return to the set interval; if the particle size of the granulated slag is smaller than the set The interval is adjusted to the set interval by fine-tuning the small granulator speed.

In the granulation process, if the particle size of the granulated slag is within the set interval, but the proportion of the granulated product is high, the granulator rotation speed, the outflow flow rate, the viscosity temperature characteristic, and the granulation can be appropriately adjusted. The surface roughness of the device, the air volume and angle of the edge of the granulator, etc., achieve the goal of small particle size of the granulated slag and low proportion of filaments.

If the known viscosity-temperature characteristics of the slag cannot meet the requirements for controlling the particle size of the granulated slag, the particle size can be controlled by adjusting the alkalinity of the slag to adjust the viscosity-temperature characteristics of the slag.

(3) Granulation slag particle activity:

The slag particles with small particle size and high glass content after granulation are used to increase the activity of the slag particles by the following methods: reducing the fineness of the granulated slag particles by mechanical grinding method, and exciting the activity of the slag particles; adding an appropriate amount of activator to increase The activity of the slag particles.

The liquid slag dry centrifugal granulation slag grain quality control method is applicable to a plurality of liquid slag dry centrifugal granulation and waste heat recovery systems, and a liquid slag dry centrifugal granulation system is proposed here:

The liquid slag dry centrifugal granulation system comprises: a granulator 219, a granulator fixing device 232 and a granulator driving device; the granulator 219 has a disk shape or a cup shape, and the edge inclination angle is 30° to 60°, the center A flow guiding cone is provided; the granulator 219 is fixed on the granulator fixing device 232; the granulator fixing device 232 is internally provided with an air flow passage 233; and the granulator fixing device 232 is connected to the bottom of the granulator 219 to provide extended heat. The surface 234, such as an annular rib, can better cool the granulator fixture; the granulator fixture 232 has a plurality of first tuyères 236 at the top, and the outlet angle of the first tuyere and the edge of the granulator When intersected, the liquid film or liquid filament formed during the granulation process can be externally broken to enhance the granulation effect; the granulator fixing device 232 is provided with a plurality of second tuyères 235 on the side, and the second tuyere and the edge of the granulator are inclined Parallel or cross, the droplets formed by the liquid filament breakage during granulation can be cooled to increase the glass transition rate. The first tuyere 236 and the second tuyere 235 are in communication with the air flow passage 233.

The granulator driving device includes a motor 209, a sealing cover 210, a rotating shaft 223, a shaft sleeve 222, an inner tube sleeve 217, an outer tube sleeve 216, a hood 220, and the like. The motor 209 and the rotating shaft 223 are coupled by a coupling 211; the rotating shaft is provided with a plurality of temperature-resistant blades 224; the bottom of the rotating shaft 223 is provided with a temperature-resistant thrust bearing 212, and one or more temperature-resistant positioning bearings 221 are provided at the middle and the upper portion of the rotating shaft. The uppermost positioning bearing should be as close as possible to the bottom of the granulator fixing device 232. On the one hand, the rotating shaft of the high-speed rotating shaft can be improved due to the inaccurate mechanical structure, thereby affecting the granulation effect, and on the other hand, the life of the device can be prolonged.

The shaft cooling air duct includes a motor seal cover 210, an air duct inner sleeve 217, a shaft sleeve 222, and a rotating shaft 223. The sealing cover 210 surrounds the outer circumference of the motor 209, and the inner sleeve 217 and the shaft sleeve 222 are sleeved on the outer circumference of the rotating shaft 223; the inner rings of the temperature-resistant thrust bearing 212 and the temperature-resistant positioning bearing 221 are fixed on the rotating shaft 223, and the outer ring Fixed to the inner wall of the inner sleeve 217 of the air duct; the shaft sleeve 222 is fixed between the outer ring of the upper temperature-resistant bearing and the outer ring of the lower temperature-resistant bearing thereof, and the temperature-resistant blade 224 is surrounded therein; the temperature-resistant thrust bearing 212 and The air temperature locating bearing 221 is provided with a supply air flow path 218. A granulator fixing device 232 is fixed to the top of the rotating shaft 223.

The sealing cover 210 is fixedly connected to the inner tube sleeve 217, communicates through the vent 226, and the shaft cooling air enters from the sealing cover tuyere 227. After cooling the rotating shaft 223 through the inside of the shaft sleeve 222, most of it enters the granulator fixing device 232. The air flow passage 233 enters the granulation chamber from the plurality of first tuyere 236 and the second tuyere 235 which are annularly distributed from the top and the side wall of the granulator fixing device 232, and a small portion from the granulator fixing device 232 and the inner tube sleeve 217 A narrow gap enters the granulation bin. An outer tube sleeve 216 is disposed on the outer circumference of the inner tube sleeve 217, and an annular cooling air passage is formed between the inner tube sleeve 217 and the outer tube sleeve 216. The top of the annular cooling air channel is annularly arranged with a plurality of hoods 220, and the hood 220 The air outlet is lower than the air outlets of the first tuyere 236 and the second tuyere 235. An annular cooling air duct air inlet 225 is opened at the bottom of the outer tube sleeve 216.

In the present invention, the granulator fixing device 232 is composed of two parts, left and right, and is fixed by a pin and a hoop. When the granulator 219 is damaged, the pin is removed, the granulator 219 and the granulator fixing device 232 can be removed, the pin and the hoop can be removed, and the left and right parts of the granulator fixing device 232 can be disassembled and removed. The granulator 219 can be removed after the annular clamp. When the granulator 219 is cracked, the cracked granulator 219 is not smashed due to the presence of the granulator base and the fixture, and the liquid slag does not drip directly onto the transmission and the motor 209. Ensure system safety before downtime. At the same time, it is only necessary to replace the granulator 219, which reduces the cost of replacing the entire granulator by the general granulator 219 due to damage. The granulator fixing device 232 is internally provided with a streamlined flow passage 233; at the same time, the gap between the bottom side of the granulator base and the inner sleeve 217 of the air duct is small, so that most of the wind sent from the lower portion of the granulator base can enter. To the streamlined flow passage 233, the granulator fixture 232 is cooled while facilitating the blowing of wind from the granulator base to the edge of the granulator 219 to enhance granulation.

In the present invention, the rotating shaft 223 and the granulator fixing device 232 are connected by a hollow flange, and the hollow flange has a section of air heat insulating layer between the granulator base and the rotating shaft 223 to block the granulator 219 and the rotating shaft 223. The heat transfer between the granulator base is not transmitted to the rotating shaft 223, so that the granulator 219 can be safely and stably operated, and the granulation effect can be better realized.

There are three ways to generate the shaft cooling air: mode one, the cooling air is generated by the fan, entering from the sealing hood tuyere 227, most of the annular air duct passing through the granulator fixing device enters the granulation chamber, and a small part is from the fixing device and the air duct inner sleeve. The narrow gap between the cylinders 217 enters the granulation chamber; in the second embodiment, the first and second or multi-stage small temperature-resistant blades 224 are arranged on the rotating shaft 223, and the cooling wind is generated by the high-speed rotation of the rotating shaft, and most of them are fixed by the granulator. The annular duct of unit 232 enters the granulation chamber and a small portion enters the granulation chamber from a narrow gap between the fixture and the inner sleeve 217 of the duct. The rotating shaft 223 is provided with one-stage, two-stage or multi-stage small temperature-resistant blades 224. When the rotating shaft 223 rotates at a high speed, on the one hand, the flow power of the shaft cooling air passage is generated, and the acceleration shaft cooling air shaft and the granulator fixing device are generated. Cooling, on the other hand, the temperature-resistant blade 224 can also be used as a rib structure to enhance the overall heat dissipation of the rotating shaft 223; in the third mode, the wind blower and the small temperature-resistant blade are combined with the high-speed rotating wind as the shaft cooling wind, and the shaft cooling wind Cooling of components such as the track and the shaft.

It should be noted that the above embodiments are merely illustrative of the present invention and are not intended to limit the technical solutions described in the present invention; therefore, although the present specification has been described in detail with reference to the various embodiments described above, It will be understood by those skilled in the art that the present invention may be modified or equivalently substituted without departing from the spirit and scope of the invention.

Claims (10)

The method for controlling the quality of dry granulated granulated slag particles of liquid slag is characterized in that the slag grain quality includes the glass body conversion rate of the slag particles, the particle size and distribution of the slag particles, and the slag particle activity; the liquid slag dry granules The slag particle quality control methods include: (1) regulation of vitreous conversion of slag particles; The glass slag conversion rate is related to the cooling rate. By rapid cooling, the slag particles rapidly cross the crystal phase transition region to realize the slag particle amorphous phase transition; (2) Controlling the particle size and particle size distribution of the slag particles; (3) Granulation slag particle activity: The fineness of the granulated slag particles is reduced by a mechanical grinding method to activate the activity of the slag particles; or an activator is added to increase the activity of the slag particles. The method according to claim 1, wherein the step (1) specifically comprises: Rapid cooling of high-temperature granulated slag particles in the granulating bin: set the granulator edge cooling wind, combined with the trajectory of the granulated slag particles, matching the cooling air flow field and momentum; setting the granulated water wall or the granulated silo wall Membrane cooling wind, combined with the flight path of the granulated slag particles, matching the volume of the granulation bin and the wall temperature of the granulated water wall or the temperature and wind speed of the film cooling wind on the wall of the granulated bin; the granulator edge is used to cool the wind, Granular water wall or film cooling wind, strengthen the radiant heat transfer and convective heat transfer of high temperature granulated slag particles and the surrounding environment, and achieve rapid cooling of high temperature granulated slag particles; In the moving bed or fluidized bed, a cold wall is arranged on the moving bed or the wall of the fluidized bed, and the cold wall adopts a membrane wall or a non-membrane wall, and the cooling wall or the cooling water is passed through the cold wall to realize the adhering layer and the cold layer. Wall solid-solid heat transfer; a buried pipe is arranged in the moving bed or the fluidized bed space, and the cooling pipe or the cooling water is passed through the buried pipe, and the buried pipe adopts a round pipe or a wear-resistant shaped pipe, and passes through the moving bed or the fluidized bed inner layer Solid-solid heat transfer with the wall of the buried pipe, control the cooling rate of the molten layer and the semi-melted layer inside the moving bed or the fluidized bed slag, realize the vitreous transformation of the slag particles; pass the cooling wind in the moving bed or the fluidized bed The convective heat transfer between the material layer and the cooling air realizes the glass body transformation of the slag particles; at the same time, the heating surface of the buried pipe is arranged between the moving bed and the granulation bin, the cooling fluid is passed through the buried pipe, and the buried pipe adopts a round pipe or a wear-resistant shaped pipe. . The method for controlling the quality of a liquid slag dry centrifugal granulated slag according to claim 1, wherein the particle size and particle size distribution of the slag particles are controlled based on a liquid slag dry centrifugal granulation system; The slag dry centrifugal granulation system includes: a temperature control unit for controlling the high temperature slag in the liquid slag buffer device to maintain the set temperature range, and controlling the outflow slag temperature of the buffer device to maintain the set temperature range; a flow control unit for controlling the flow rate of the high-temperature slag flowing out of the buffer device in a set range to ensure the smoothness of the flow; a granulator control unit for controlling the centering of the granulator center and the center of the slag tube of the buffer device, and ensuring smooth operation of the granulator during high-speed rotation; Step (2) specifically includes the following steps: First, through the temperature control unit, flow control unit and granulator control unit, control the temperature and flow rate of the liquid slag falling into the granulator, and ensure that the granulator and the slag tube are centered and smooth without shaking; then enter the commissioning Through the process test, adjusting the granulator rotation speed, outflow flow rate, viscosity temperature characteristics, granulator structure, granulator size, granulator surface roughness, granulator edge wind speed and angle, to obtain granulated slag particles Particle size and granulator rotation speed, outflow flow rate, viscosity temperature characteristics, granulator structure, granulator size, granulator surface roughness, granulator edge wind speed and angle; When the process test is used to obtain the granulated particle size and granulator rotation speed, the outflow flow rate, the viscosity temperature characteristic, the granulator structure, the granulator size, the granulator surface roughness, the granulator edge wind speed and the angle After the relationship, the normal granulation process begins; If the particle size of the granulated slag obtained according to the above particle size relationship is larger than the set interval during the normal granulation process, the granule speed of the granulator is finely adjusted to return to the set interval; if the particle size of the granulated slag is smaller than the set The interval is adjusted to the set interval by fine-tuning the small granulator speed. The method for controlling the quality of a liquid slag dry centrifugal granulated slag according to claim 1, wherein in the regulation of the glass transition rate of the slag particles, a moving bed structure is adopted, and the surface of the moving bed layer is disposed near the surface of the moving bed layer. The squeegee periodically pushes or rotates the pusher layer to evenly material, and the squeegee has cooling air. The method for controlling the quality of a liquid slag dry centrifugal granulated slag according to claim 3, wherein in the method for controlling the vitreous conversion rate of the slag particles, if it is ensured that each parameter is within a set value range Under the premise, the vitreous conversion rate of the slag particles is detected during the granulation process, and if the conversion rate is less than the set value, the process proceeds to step (a); if the conversion rate is greater than the set value, the process ends; and the vitreous conversion rate of the slag particles is continuously monitored; (a) Confirm whether the liquid slag particle size is within the set interval. If it exceeds the set interval, adjust the slag particle size to the set interval and go to step (b); if it does not exceed the set interval, directly turn Into step (b); (b) Gradually increase the annular air volume at the edge of the granulator until the vitreous conversion rate of the granulated slag particles reaches the set value, and ends; if the annular air volume at the edge of the granulator increases to the maximum, the vitreous conversion rate of the granulated slag particles is still less than Set the value and go to step (c); (c) If there is a film cooling wind on the wall of the granulated silo, gradually increase the amount of film cooling air on the wall of the granulated silo until the vitreous conversion rate of the granulated slag reaches the set value; The film cooling air volume is increased to the maximum on the wall of the chemical silo, and the glass body conversion rate of the granulated slag particles is still less than the set value, and is transferred to step (d); if there is no air film cooling wind on the granulated silo wall, Transfer to step (d); (d) If a scraper cooling wind is provided near the surface of the moving bed layer, the amount of the scraper surface of the moving bed layer is increased until the vitreous conversion rate of the granulated slag particles reaches a set value, and ends; if the surface of the bed layer is moved The scraper cooling air volume set nearby is added to the maximum, and the vitreous conversion rate of the granulated slag particles is still less than the set value, and the process proceeds to step (e); if no scraper cooling wind is disposed near the surface of the moving bed layer, the transfer step is performed. (e); (e) increasing the cooling air volume of the moving bed until the vitreous conversion rate of the granulated slag particles reaches the set value, and ends; if the moving bed cooling air volume is maximized, the vitreous conversion rate of the granulated slag particles is still less than the set value, and is transferred. Step (f); (f) Adjust the operation according to the relationship between particle size and granulator rotation speed, outflow flow rate, viscosity-temperature characteristics, granulator structure, granulator size, granulator surface roughness, granulator edge wind volume and angle Parameters and slag properties to reduce the particle size of the slag until the vitreous conversion of the granulated granules reaches a set value; if the particle size of the slag is reduced to the limit, the vitreous conversion of the granulated granules is still less than Set the value and go to step (g); (g) Increasing the moving bed level until the vitreous conversion of the granulated granules reaches a set value. The method according to claim 3, wherein the liquid slag dry centrifugal granulation system comprises: a granulator (219) and a granulator fixing device ( 232) and a granulator driving device; the granulator is fixed on the granulator fixing device (232); the granulator fixing device is internally provided with an air flow passage (233), and the granulator fixing device contacts the bottom of the granulator Expanding the heated surface (234); the top of the granulator fixture is provided with a plurality of first tuyères (236), and the outlet angle of the top first tuyere intersects the dip angle of the edge of the granulator for the liquid formed during the granulation process The membrane or liquid filament is subjected to external force crushing; a plurality of second tuyères (235) are arranged on the side of the granulator fixing device (232), and the second tuyere is parallel or intersected with the inclination angle of the edge of the granulator for the liquid during the granulation process. The droplets formed by the filament breakage are cooled; the first tuyere and the second tuyere are in communication with the gas flow passage (233); the granulator drive is used to drive the granulator to rotate. The liquid slag dry centrifugal granulated slag grain quality control method according to claim 6, further comprising a granulator driving device and a shaft cooling air passage; The granulator driving device comprises a motor (209) and a rotating shaft (223); the output shaft of the motor (209) is fixedly connected with the lower end of the rotating shaft (223); the upper end of the rotating shaft is fixedly connected with the bottom of the granulator fixing device (232); a plurality of temperature resistant blades (224) are disposed on the rotating shaft; The shaft cooling air duct includes a motor sealing cover (210), an inner tube sleeve (217), a shaft sleeve (222) and a rotating shaft (223); the sealing cover (210) surrounds the outer circumference of the motor (209), and the inner tube of the air duct ( 217) and the shaft sleeve (222) is sleeved on the outer circumference of the rotating shaft (223); the inner ring of the temperature resistant thrust bearing (212) and the temperature resistant positioning bearing (221) are fixed on the rotating shaft (223), and the outer ring is fixed at The inner wall of the inner sleeve (217); the shaft sleeve (222) is fixed between the outer ring of the temperature-resistant bearing at the top thereof and the outer ring of the temperature-resistant bearing at the lower portion thereof, and the temperature-resistant blade (224) is surrounded therein; Both the temperature thrust bearing (212) and the temperature resistant positioning bearing (221) are provided with an air flow passage (218); The sealing cover (210) is fixedly connected with the inner tube sleeve (217) and communicated through the vent (226); An outer sleeve (216) is arranged on the outer circumference of the inner sleeve (217) of the air duct, and an annular cooling air duct is formed between the inner sleeve (217) of the air duct and the outer sleeve (216) of the air duct, and the annular cooling duct is arranged at the top of the annular shape. There are a number of hoods (220); the bottom of the outer sleeve of the duct is provided with an annular cooling duct air inlet (225). The method for regulating the quality of a liquid slag dry centrifugal granulated slag according to claim 6, wherein the shaft cooling air enters from the sealing hood tuyere, and after cooling through the shaft sleeve to the rotating shaft, most of the granulator enters the granulator. The air flow passage of the fixing device enters the granulation chamber from a plurality of first air outlets and second air outlets uniformly distributed on the top and side walls of the granulator fixing device, and a small portion is narrow between the granulator fixing device and the inner sleeve of the air duct The gap enters the granulation bin. The method for regulating the quality of a liquid slag dry centrifugal granulated slag according to claim 6, wherein the air outlet of the hood is lower than the air outlets of the first tuyere and the second tuyere. The method according to claim 6, wherein the shaft cooling air has three production modes: In the first mode, the cooling air is generated by the fan, entering from the sealing hood tuyere (227), and most of the airflow passage (233) passing through the granulator fixing device flows out, and a small portion is between the fixing device and the inner tube sleeve (217). a small gap flows out; In the second mode, the temperature-resistant blade (224) on the rotating shaft (223) generates cooling air according to the high-speed rotation of the rotating shaft, and most of the airflow passage (233) flows out through the granulator fixing device (232), and a small portion is fixed from the fixing device. a narrow gap between the inner sleeve (217) of the air duct; In the third mode, the fan air outlet and the high temperature rotating blade of the temperature resistant blade cooperate as the shaft cooling wind to cool the shaft cooling air duct and the rotating shaft.

Images