A method for granulating dust-removing coke powder

Abstract

The present invention belongs to the technical field of processing and utilization of solid waste from iron and steel metallurgy, and in particular relates to a method for granulating dust-removed coke powder. It comprises a dust-removed coke powder silo, the discharge end of which is connected to a powerful mixing pelletizing and granulating machine via a screw feeder, the output end of which is connected to a rotary distributor via a belt conveyor, the discharge end of the rotary distributor is connected to a rotary drum dryer, the discharge end of the rotary drum dryer is connected to a multi-roller particle crusher via a chain transmission belt, and the feed end of the powerful mixing pelletizing and granulating machine is connected to an adhesive silo via a grouting pipe. The present invention changes the physical properties of the dust-removed coke powder by granulating, drying, finely crushing, and shaping the dust-removed coke powder, so that the dust-removed coke powder meets the requirements for reuse, thereby recovering the dust-removed coke powder. The process of the present invention is relatively simple, has little waste, high processing efficiency, and can achieve rapid batch processing.

Description

Technical Field

[0001] The invention belongs to the technical field of processing and utilizing solid waste from iron and steel metallurgy, and in particular relates to a method for granulating dust-removed coke powder. Background Art

[0002] The dry quenching process in coking plants of metallurgical enterprises produces a large amount of solid waste dust coke powder with a particle size of less than 3mm. The main ways to use the dusted coke powder are: first, it is mixed with coke or anthracite and used as fuel for sintering. A small amount of dusted coke powder is used for coking with return coal. Relevant research shows that the appropriate ratio of return coal for coking is about 1%. Coking cannot completely consume the coke powder it produces, and a large amount of dusted coke powder is still unused; second, it is used in the blast furnace ironmaking process, but because the coke powder particle size is too small, it will be blown away by the air flow in the furnace during the pig iron smelting process, and thus cannot play its due role as a skeleton, reduction and heat source, resulting in significant losses; third, it can be used in the steelmaking process, but there are currently few reports on the use of dusted coke powder in the steelmaking process. How to solve the problem of small powder particle size and low utilization rate of dusted coke powder is a problem that technicians in this field urgently need to solve.

[0003] Patent application number 201410295160.3 discloses a coke powder pelletizing device and a coke powder pelletizing process. The patent uses warm asphalt as a binder. After the coke powder and warm asphalt are mixed, they are heated through a heat-insulating homogenizer and then pressed into balls through a pelletizing machine. The patent has the following deficiencies: when using warm asphalt as a binder, it must be heated first and must be kept warm to prevent solidification, resulting in high energy consumption. Moreover, during the heating, heat-insulating, mixing and pelletizing processes, the coke powder, asphalt and equipment will stick together. After a period of use, the equipment needs to be cleaned or even disassembled for maintenance. The use of warm asphalt as a binder has a relatively single component, and the high asphalt content increases the viscosity of the final coke powder pellets, making them brittle and not conducive to pellet breaking. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for granulating dust-removed coke powder to solve the problems existing in the prior art.

[0005] The technical solution adopted by the present invention to solve its technical problem is: a dust-removing coke powder pelletizing processing device, including a dust-removing coke powder silo, the discharge end of the dust-removing coke powder silo is connected to a strong mixing ball-making and granulating integrated machine through a spiral feeder, the output end of the strong mixing ball-making and granulating integrated machine is connected to a rotary distributor through a belt conveyor, the discharge end of the rotary distributor is connected to a rotary drum dryer, the discharge end of the rotary drum dryer is connected to a multi-roller particle crusher through a chain transmission belt, and the feed end of the strong mixing ball-making and granulating integrated machine is connected to an adhesive through a grouting pipe. The grouting machine is installed on the grouting pipeline, the air inlet end of the rotary drum dryer is connected to the indirect gas hot air furnace, the air outlet end of the rotary drum dryer is connected to the cyclone separator through the air duct, the air outlet end of the cyclone separator is connected to the induced draft fan through the air duct, the dust removal coke powder silo, the spiral feeder, the strong mixing ball making and granulation machine, the belt conveyor, the rotary distributor, the rotary drum dryer, the chain drive belt, the multi-roller particle crusher, the adhesive silo, the grouting machine, the indirect gas hot air furnace, the cyclone separator, the induced draft fan and the control system are electrically connected.

[0006] A method for granulating dust-removed coke powder comprises the following steps:

[0007] (1) Preparation of composite adhesive: Mix the adhesive raw materials evenly to form a mixture, add industrial water to the adhesive bin and start the mixing of the adhesive bin and slowly add the mixture. The principle of adding the mixture is to add it as needed and avoid forming lumps during the addition process. After the mixture is added, stir it for more than 5 minutes to obtain the composite adhesive;

[0008] (2) Mixing and granulating: the dusted coke powder in the dusted coke powder silo and the composite adhesive in the adhesive silo are added to the powerful mixing and pelletizing integrated machine, and the mixing and pelletizing are carried out for more than 20 minutes. The shape of the pellets is controlled by adjusting the rotating mixing drum and rotor speed of the powerful mixing and pelletizing integrated machine to obtain coke powder ellipsoids;

[0009] (3) Drying: The coke powder ellipsoids are fed into a rotary distributor via a belt conveyor, and the rotary distributor evenly feeds the coke powder ellipsoids into a rotary drum dryer. The temperature in the rotary drum dryer is controlled by an indirect gas hot air furnace, a cyclone separator, and an induced draft fan, so that the coke powder ellipsoids tumble and exchange heat in the rotary drum dryer. Drying is continued for 1.5-2 hours to obtain dry coke balls and a gas-solid mixture.

[0010] (4) Coke recovery: Control the induced draft fan flow rate at 30,000 m 3 / h, the induced draft fan generates negative pressure, guiding the gas-solid mixture into the cyclone separator. The gas-solid mixture is caused to rotate by the airflow guidance. The solid particles are separated from the gas by the large inertial centrifugal force. The solid particles are collected by the bag in the cyclone separator and returned to the silo for reuse as raw materials for dust removal coke powder pelletizing.

[0011] (5) Fine crushing and shaping: The dried coke balls are sent to a multi-roller particle crusher through a chain transmission belt for fine crushing and shaping to obtain coke powder pellets.

[0012] Furthermore, in step (1), the binder raw materials are carbon material binder, bentonite, and dry powder binder, and the mixed mass parts of the mixture are 6 parts of carbon material binder, 3 parts of bentonite, and 1 part of dry powder binder.

[0013] Furthermore, in step (1), the mass proportions of the mixed material and industrial water added are 10 parts of the mixed material and 8 parts of industrial water.

[0014] Furthermore, in step (2), the weight proportions of the dust-removed coke powder and the composite adhesive added are 86-88 parts of the dust-removed coke powder and 12-14 parts of the composite adhesive.

[0015] Furthermore, in step (2), the ventilation pressure of the intensive mixing, pelletizing and granulating integrated machine during mixing and granulating is 0.4 MPa and the temperature is less than 55°C.

[0016] Furthermore, the index of the coke powder ellipsoid in step (2) is: particle size is φ10-20mm.

[0017] Furthermore, in step (3), the temperature of the rotary drum dryer is controlled at 240-310° C. when drying the coke powder ellipsoids, and the control index of the drying coke balls is that the moisture content is less than 1%.

[0018] Furthermore, the indexes of the coke powder pellets in step (5) are: particle size φ1-3mm, bulk density 0.05-0.08g / cm 3 , the particle crushing strength coefficient is greater than 45%.

[0019] Furthermore, in step (5), the multi-roller particle crusher adopts an upper and lower set of rollers in a vertically arranged structure. The upper set of rollers adopts φ450×550mm grooved rollers, and the lower set of rollers adopts φ380×450mm toothed rollers, forming two independent upper and lower crushing groups. The dust-removed coke powder ellipsoid passes through the upper set of grooved rollers, is roughly crushed, and then falls into the lower set of toothed rollers for crushing and reshaping.

[0020] The present invention has the following beneficial effects:

[0021] 1. The composite adhesive can bind fine dust removal coke powder for easy processing and utilization, and the prepared coke powder pellets have little effect on the fixed carbon, volatile matter and ash content of the dust removal coke powder.

[0022] 2. The process is relatively simple, with less waste, high processing efficiency, and rapid batch processing.

[0023] 3. The size of the processed coke powder pellets is uniform in the range of φ1-3mm, the particle crushing strength coefficient is greater than 45%, the compressive strength is high, and the bulk density is 0.05-0.08g / cm 3 , which can fully meet the needs of production.

[0024] 4. Coke powder pellets can be widely used in the coking, sintering, ironmaking and steelmaking processes of steel metallurgy, which improves the physical properties of raw materials and increases the utilization efficiency of coke powder.

[0025] 5. The dust-removed coke powder is recycled and made into coke powder pellets for use in steel production, which reduces the emission of solid waste, reduces environmental pollution, and reduces the cost of steel production.

[0026] 6. Compared with other granulators, the powerful mixing and pelletizing integrated machine has the advantages of uniform mixing, high granulation strength, high efficiency, uniform particle size of coke powder ellipsoids and less dust. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the dust removal coke powder pelletizing processing device of the present invention.

[0028] Figure 2 It is a schematic diagram of dust removal of coke powder in the present invention.

[0029] Figure 3 It is a schematic diagram of the coke powder ellipsoid of the present invention.

[0030] Figure 4 It is a schematic diagram of coke powder pelletizing according to the present invention.

[0031] Among them: 1. Dust removal coke powder silo; 2. Screw feeder; 3. Adhesive silo; 4. Grouting machine; 5. High-pressure mixing ball-making and granulation machine; 6. Belt conveyor; 7. Rotary distributor; 8. Rotary drum dryer; 9. Cyclone separator; 10. Induced draft fan; 11. Chain drive belt; 12. Multi-roller particle crusher; 13. Indirect gas hot air furnace; 14. Grouting pipeline; 15. Air duct. DETAILED DESCRIPTION

[0032] The present invention will now be described in further detail with reference to the accompanying drawings. Example 1

[0033] like Figure 1As shown, a dust removal coke powder granulation processing device includes a dust removal coke powder material bin 1, the discharge end of the dust removal coke powder material bin 1 is connected to a strong mixing ball making and granulation integrated machine 5 through a screw feeder 2, the output end of the strong mixing ball making and granulation integrated machine 5 is connected to a rotary distributor 7 through a belt conveyor 6, the discharge end of the rotary distributor 7 is connected to a rotary drum dryer 8, the discharge end of the rotary drum dryer 8 is connected to a multi-roller particle crusher 12 through a chain transmission belt 11, the feed end of the strong mixing ball making and granulation integrated machine 5 is connected to an adhesive bin 3 through a grouting pipe 14, and the grouting pipe 14 is connected to the adhesive bin 3. A grouting machine 4 is installed, the air inlet end of the rotary drum dryer 8 is connected to an indirect gas hot air furnace 13, the air outlet end of the rotary drum dryer 8 is connected to a cyclone separator 9, the air outlet end of the cyclone separator 9 is connected to an induced draft fan 10, the dust removal coke powder silo 1, the spiral feeder 2, the strong mixing ball making and granulation integrated machine 5, the belt conveyor 6, the rotary distributor 7, the rotary drum dryer 8, the chain drive belt 11, the multi-roller particle crusher 12, the adhesive silo 3, the grouting machine 4, the indirect gas hot air furnace 13, the cyclone separator 9, the induced draft fan 10 are electrically connected to the control system.

[0034] A method for granulating dust-removed coke powder, characterized by comprising the following steps:

[0035] (1) Preparation of composite adhesive: 600 kg of carbon adhesive, 300 kg of bentonite and 100 kg of dry powder adhesive are put into adhesive bin 3 and mixed evenly to form 1 t of mixture. 800 kg of industrial water is added to adhesive bin 3 and the stirring of adhesive bin 3 is turned on and the mixture is slowly added. The principle of adding the mixture is to add it as needed and avoid forming lumps during the addition process. After the mixture is added, stir it for more than 5 minutes to obtain 1 t of composite adhesive. 1 t of composite adhesive can be used in about 8 batches.

[0036] (2) Mixing and granulation: The dust-removed coke powder is pushed from the dust-removed coke powder silo 1 into the powerful mixing and pelletizing integrated machine 5 at a constant speed and quantity through the screw feeder 2. The screw feeder 2 is provided with a weighing module. The variable control of the screw feeder 2 is adjusted by the control system to achieve stable constant number and constant weight feeding control. The constant is level 2, 1200 rpm. The flow rate and flow velocity of the grouting machine 4 are controlled by the control system, and synchronous feeding is achieved in conjunction with the feeding speed of the screw feeder 2. The dust-removed coke powder addition amount is 880 kg, and the composite adhesive addition amount is 140 kg. The temperature in the powerful mixing and pelletizing integrated machine 5 is adjusted to less than 55°C through the control system, and the ventilation pressure is controlled at 0.4 MPa. The mixing and granulation is carried out for more than 20 minutes. The shape of the granulation is controlled by adjusting the rotating mixing drum and rotor speed of the powerful mixing and pelletizing integrated machine 5 to obtain coke powder ellipsoids with a particle size of φ10-20 mm.

[0037] (3) Drying: The coke powder ellipsoids are fed into the rotary distributor 7 via the belt conveyor 6. The rotary distributor 7 evenly feeds the coke powder ellipsoids into the rotary drum dryer 8. The temperature in the rotary drum dryer 8 is controlled at 240-310°C via the indirect gas hot air furnace 13, the cyclone separator 9, and the induced draft fan 10. The coke powder ellipsoids are subjected to tumbling motion and heat exchange in the rotary drum dryer 8. Drying is stopped when the moisture content of the coke powder ellipsoids is less than 1%. The drying time is 1.5-2 hours to obtain a gas-solid mixture and dried coke balls.

[0038] (4) Recover coke powder: Control the flow rate of induced draft fan 10 at 30000m 3 / h, the induced draft fan 10 generates negative pressure, guiding the gas-solid mixture into the cyclone separator 9. The gas-solid mixture is caused to rotate by the airflow guidance. The solid particles are separated from the gas by the large inertial centrifugal force. The solid particles are collected by the bags in the cyclone separator 9. When the bags are full or the filtering effect is poor, new bags are immediately replaced and the collected solid particles are returned to the silo for reuse as raw materials for dust-removed coke powder pelletizing.

[0039] (5) Fine crushing and shaping: The dried coke balls are sent to the multi-roller particle crusher 12 through the chain transmission belt 11. The multi-roller particle crusher 12 adopts an upper and lower set of rollers with a vertically arranged structure. The upper set of rollers adopts φ450×550mm grooved rollers, and the lower set of rollers adopts φ380×450mm toothed rollers, forming two independent upper and lower crushing groups. The dust-removed coke powder ellipsoids pass through the upper set of grooved rollers, are roughly crushed, and then fall into the lower set of toothed rollers for crushing and shaping again to obtain coke powder pellets. The indicators of coke powder pellets are: particle size of φ1-3mm, bulk density of 0.05-0.08g / cm 3 , the particle crushing strength coefficient is greater than 45%.

[0040] like Figure 2 As shown in the figure, the dust-removed coke powder is in powder form before pelletizing. If it is directly added into the furnace, it will be blown away by the airflow in the furnace, and thus cannot play the role of skeleton, reduction and heat source, resulting in a large loss.

[0041] like Figure 3 As shown in the figure, after mixing, granulation and drying, the dry coke ball has an elliptical cake shape with a larger volume, a greatly improved strength, and the moisture content is reduced to below 1%, but further fine crushing and shaping are still needed;

[0042] like Figure 4 As shown in the figure, after fine crushing and shaping, the final coke powder pellets are in the shape of granules. After testing, the particle size is in the range of φ1-3m, and the bulk density is 0.05-0.08g / cm 3 , the particle crushing strength coefficient is greater than 45%, which fully meets the production and use requirements.

[0043] Example 2: This example provides a method for pelletizing dust-removed coke powder. The processing device and processing method are basically the same as those in Example 1, except that the amount of dust-removed coke powder input in step (2) is 860 kg and the amount of composite adhesive input is 120 kg.

[0044] Example 3: This example provides a method for pelletizing dust-removed coke powder. The processing device and method are basically the same as those in Example 1, except that the amount of dust-removed coke powder input in step (2) is 850 kg and the amount of composite adhesive input is 130 kg.

[0045] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the concept and scope of the present invention. Various modifications and improvements made to the technical solution of the present invention by ordinary persons in the art without departing from the design concept of the present invention should all fall within the scope of protection of the present invention.

[0046] The technology, shape, and structure not described in detail in the present invention are all well-known technologies.

Claims

1. A method for granulating dust-removed coke powder, characterized in that: The following steps are involved: (1) Preparation of composite adhesive: Mix the adhesive raw materials evenly to form a mixture, add industrial water to the adhesive bin and start the mixing of the adhesive bin and slowly add the mixture. The principle of adding the mixture is to add it as needed and avoid forming lumps during the addition process. After the mixture is added, stir it for more than 5 minutes to obtain the composite adhesive; (2) Mixing and granulating: the dusted coke powder in the dusted coke powder silo and the composite adhesive in the adhesive silo are added to the powerful mixing and pelletizing integrated machine, and the mixing and pelletizing are carried out for more than 20 minutes. The shape of the pellets is controlled by adjusting the rotating mixing drum and rotor speed of the powerful mixing and pelletizing integrated machine to obtain coke powder ellipsoids; (3) Drying: The coke powder ellipsoids are fed into a rotary distributor via a belt conveyor, and the rotary distributor evenly feeds the coke powder ellipsoids into a rotary drum dryer. The temperature in the rotary drum dryer is controlled by an indirect gas hot air furnace, a cyclone separator, and an induced draft fan, so that the coke powder ellipsoids tumble and exchange heat in the rotary drum dryer. Drying is continued for 1.5-2 hours to obtain dry coke balls and a gas-solid mixture. (4) Coke recovery: Control the induced draft fan flow rate at 30,000 m 3 / h, the induced draft fan generates negative pressure, guiding the gas-solid mixture into the cyclone separator. The gas-solid mixture is caused to rotate by the airflow guidance. The solid particles are separated from the gas by the large inertial centrifugal force. The solid particles are collected by the bag in the cyclone separator and returned to the silo for reuse as raw materials for dust removal coke powder pelletizing. (5) Fine crushing and shaping: The dried coke balls are sent to a multi-roller pellet crusher through a chain transmission belt for fine crushing and shaping to obtain coke powder pellets; In step (1), the binder raw materials are carbon material binder, bentonite, and dry powder binder, and the mixed mass parts of the mixture are 6 parts of carbon material binder, 3 parts of bentonite, and 1 part of dry powder binder; The discharge end of the dust removal coke powder bin is connected to a strong mixing ball making and granulating integrated machine through a screw feeder, the output end of the strong mixing ball making and granulating integrated machine is connected to a rotary distributor through a belt conveyor, the discharge end of the rotary distributor is connected to a rotary drum dryer, the discharge end of the rotary drum dryer is connected to a multi-roller particle crusher through a chain transmission belt, the feed end of the strong mixing ball making and granulating integrated machine is connected to an adhesive bin through a grouting pipe, a grouting machine is installed on the grouting pipe, and the rotary drum dryer is connected to a plurality of roller particle crushers. The air inlet end of the machine is connected to an indirect gas hot air furnace, the air outlet end of the rotary drum dryer is connected to a cyclone separator through an air duct, the air outlet end of the cyclone separator is connected to an induced draft fan through an air duct, the dust removal coke powder silo, spiral feeder, strong mixing ball making and granulation machine, belt conveyor, rotary distributor, rotary drum dryer, chain drive belt, multi-roller particle crusher, adhesive silo, grouting machine, indirect gas hot air furnace, cyclone separator, induced draft fan and control system are electrically connected.

2. The dust removal coke powder pelletizing method according to claim 1, characterized in that: The weight proportions of the mixed material and industrial water added in step (1) are 10 parts of the mixed material and 8 parts of industrial water.

3. The dust removal coke powder pelletizing method according to claim 1, characterized in that: In the step (2), the weight proportions of the dust-removed coke powder and the composite adhesive added are 86-88 parts of the dust-removed coke powder and 12-14 parts of the composite adhesive.

4. The dust removal coke powder pelletizing method according to claim 1, characterized in that: In the step (2), the ventilation pressure of the powerful mixing, pelletizing and granulating integrated machine during mixing and granulating is 0.4 MPa and the temperature is less than 55°C.

5. The dust removal coke powder pelletizing method according to claim 1, characterized in that: The index of the coke powder ellipsoid in step (2) is: particle size is φ10-20mm.

6. The method for granulating dust-removed coke powder according to claim 1, characterized in that: In step (3), the temperature of the rotary drum dryer is controlled at 240-310° C. when drying the coke powder ellipsoids, and the control index of the drying coke balls is that the moisture content is less than 1%.

7. The method for granulating dust-removed coke powder according to claim 1, characterized in that: The indicators of the coke powder pelletizing in step (5) are: particle size of φ1-3mm, bulk density of 0.05-0.08g / cm 3 , the particle crushing strength coefficient is greater than 45%.

8. The dust removal coke powder pelletizing method according to claim 1, characterized in that: In step (5), the multi-roller particle crusher adopts an upper and lower set of rollers in a vertically arranged structure. The upper set of rollers adopts φ450×550mm grooved rollers, and the lower set of rollers adopts φ380×450mm toothed rollers, forming two independent upper and lower crushing groups. The dust-removed coke powder ellipsoid passes through the upper set of grooved rollers, is roughly crushed, and then falls into the lower set of toothed rollers for crushing and reshaping.

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