CN100393842C - Metallurgical coke carbon plating enhancement device - Google Patents

Abstract

A metallurgical coke carbon coating enhancement device relates to the field of dry coke quenching, in particular to a metallurgical coke carbon coating enhancement device using methane-rich gas as a coke quenching medium. The device uses the sensible heat of red coke to decompose methane in the coke quenching medium into hydrogen and free carbon. The free carbon is adsorbed and filled on the coke surface and coke pores to form a dense film layer, covering the coke outer surface, and blocking the coke. internal pores. The device has an integral sealing cover, the front end of the sealing cover is connected with the red coke receiving hopper, the red coke receiving hopper is connected with the coke quenching carbon coating trolley through the piston feeder, and the bottom of the coke quenching carbon coating trolley is a gas collection box. The coke quenching medium enters the coke layer from the trolley grate on the upper part of the gas collection box. The coke quenching and carbon coating trolley is under the rear of the coke receiving hopper, and the coke receiving hopper is a water-sealed belt conveyor. The device can reduce coke reactivity and improve metallurgical coke strength after reaction.

Description

Metallurgical coke carbon plating enhancement device

technical field

The invention belongs to the field of dry coke quenching, in particular to a metallurgical coke carbon plating enhancement device using methane-rich gas as a coke quenching medium.

Background technique

Due to the large-scale blast furnace and the increase in the amount of coal injected into the blast furnace, the supporting skeleton of the coke required by the blast furnace is becoming more and more prominent, which requires coke ovens to smelt high-strength coke. However, coke oven smelting high-strength coke requires a large amount of main coking coal as raw material, and main coking coal is a kind of coking coal that is in short supply worldwide, which cannot meet the needs of steel production. Judging from the current status of coking coal resources and future development trends, it is required to further expand coking coal resources and use weak caking coal and steam coal for coking as much as possible. Develop new high-strength coke smelting technology and coke enhancement technology.

The patent 08/5486216 that Shigeno et al. applied for in the United States discloses a method of utilizing coke surface carburization to improve coke strength. Decomposition produces free carbon, which deposits on the surface of coke pores, reduces the specific surface area of coke, and thus achieves the purpose of increasing the strength of coke. This invention proposes the basic principle and method of carburizing coke, but does not explain how to achieve this in industry. method, and no corresponding process equipment has been proposed.

CDQ technology is a typical clean production technology in the iron and steel industry. It uses inert gas to pass through the red coke layer in the shaft furnace, recovers red coke sensible heat, and does not use water to quench coke, which reduces environmental pollution and water waste. , because the rate of red coke in the gas cooling process is much lower than that of water cooling, the coke cracks are reduced, and the cold strength index of coke can be improved to a certain extent. However, there are also some problems in the actual operation of CDQ, which mainly focus on the following aspects: (1) huge investment in infrastructure; (2) the effect of improving the thermal strength of coke is not significant; (3) coke is falling , Mechanical friction occurs between the wall, airflow and coke, forming a large amount of dust, resulting in a decrease in the total coke rate; (4) The high-temperature airflow after heat exchange entrains a large amount of dust, causing serious wear and tear on the rear equipment.

Contents of the invention

The technical problem to be solved by the present invention is to provide a metallurgical coke carbon plating enhancement device that can reduce the coke reactivity and improve the strength of the metallurgical coke after reaction.

In order to solve the above-mentioned technical problems, the metallurgical coke carbon plating strengthening device of the present invention includes an integral sealing cover, and there is a coke quenching carbon coating trolley in the sealing cover, and a gas outlet pipeline is arranged on the top of the cover; the front end of the sealing cover is connected with the red coke receiving hopper, and the red coke The upper part of the coke receiving hopper is connected to the environment, and the lower part is connected to the piston feeder. The piston feeder can do reciprocating mechanical movement in the pushing trough. The outlet of the pushing trough channel is equipped with a sealing baffle, and the lower part of the sealing baffle is an inclined chute. The inclined chute is located above the front end of the coke-quenching carbon-coating trolley. The trolley surface of the coke-quenching carbon-coating trolley is composed of grating bars, which have small holes for ventilation. The bottom is a gas collection box, which is evenly arranged The gas inlet pipe; the cold coke receiving hopper is located under the rear of the coke quenching and carbon coating trolley, and there is a water seal tank at the lower end of the outlet of the cold coke receiving hopper. The water seal tank is submerged in water and forms a water seal system with the hopper. The type conveyor is located under the cold coke receiving hopper.

There is a baffle plate above the surface of the above-mentioned coke-quenching carbon-coating trolley, which can prevent coke from scattering; the inside of the sealing cover is cast refractory material, and the outside is covered with welded steel plates; the piston feeder is made of refractory material and heat-resistant cast steel. The belt conveyor includes a scraper conveyor with an inclination angle and a chain conveyor; the inner surface of the gas outlet pipe is covered with a certain thickness of refractory castable material.

The device with such a structure can reduce the reactivity of coke and improve the strength of metallurgical coke after reaction, which mainly has the following advantages:

(1) It can prevent the leakage of the coke quenching medium. Since the whole system operates in a sealed cover, a baffle is used to seal the red coke entrance, which ensures the sealing effect of the coke quenching medium in one operating cycle of the piston push rod. The coke outlet adopts water seal, which also solves the leakage problem of coke quenching medium;

(2) It can prevent the entry of outside air. Only the red coke inlet and the cold coke outlet of the whole system may bring in air. Since the cold coke outlet at the rear is sealed with water, air is prevented from entering the system. Although the red coke entrance is connected to the environment, However, under the action of carbonaceous combustion in red coke, the oxides are completely burned, so the entire system can prevent the entry of air;

(3) Using methane-rich coke oven gas or natural gas as the coke quenching medium, the free carbon from the pyrolysis of methane is adsorbed and filled on the inner and outer surfaces of the coke, which has the effect of significantly increasing the coke strength;

(4) Utilize the coking production process of the iron and steel industry to by-produce hydrogen from coke oven gas or methane gas, which has the function of clean energy conversion in the metallurgical industry;

(5) A new type of horizontal CDQ device system is adopted. During the process of coke quenching and carbon plating, there is no relative movement between coke particles, which greatly reduces the amount of coke dust generated in the traditional CDQ process, reduces environmental pollution, and increases metallurgical focal rate.

Description of drawings

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

Fig. 1 is a structural diagram of a metallurgical coke carbon plating enhancement device of the present invention.

In the figure: 1. Red coke receiving hopper, 2. Piston feeder, 3. Pushing trough, 4. Sealing baffle, 5. Inclined chute, 6. Coke quenching carbon coating trolley, 7. Material blocking plate, 8 .Gas collection box, 9. Gas inlet pipe, 10. Cold coke receiving hopper, 11. Water seal tank, 12. Belt conveyor, 13. Sealing cover, 14. Gas outlet pipe.

Detailed ways

In Fig. 1, the device includes an integral sealing cover 13, a coke quenching carbon coating trolley 6 inside the sealing cover 13, a gas outlet pipeline 14 is arranged on the top of the cover; the front end of the sealing cover 13 is connected with the red coke receiving hopper 1, and the red coke The upper part of the receiving hopper 1 communicates with the environment, which is the entrance of red coke, and the lower part is open, connected to the piston feeder 2, and the piston feeder 2 can perform reciprocating mechanical movement in the pushing tank 3. The channel of the pushing tank 3 is rectangular, and the channel The outlet of the outlet is provided with a sealing baffle 4, the lower part of the sealing baffle 4 is an inclined chute 5, the inclined chute 5 is located above the front end of the coke quenching carbon coating trolley 6, and the trolley surface of the coke quenching carbon coating trolley 6 is composed of grating bars, The grate bar is provided with ventilating holes, and the bottom is a gas collecting box 8, and the gas inlet pipe 9 is evenly arranged in the gas collecting box 8; There is a water seal tank 11 at the lower end of the discharge port of the hopper 10. The water seal tank 11 is submerged in water and forms a water seal system with the hopper. The belt conveyor 12 is located below the cold coke receiving hopper 10. The coke quenching carbon coating trolley 6 There is a baffle plate 7 above the trolley surface, which can prevent coke from scattering; the inside of the sealing cover 13 is cast refractory material, and the outside is covered with welded steel plates; the piston feeder 2 uses refractory material and heat-resistant cast steel as the push head; the belt type The conveyor 12 adopts a scraper conveyor and a chain conveyor with an inclination; the inner surface of the gas outlet pipe 14 is covered with a certain thickness of refractory castable material, and the exterior of the refractory material is a seamless pipe.

Whole device has only a coke inlet and a coke outlet, a gas pipeline inlet and a gas pipeline outlet, and all equipments are all in the sealing cover 13. In this way, the quenching medium is isolated from the environment. When the red coke in the coking production process is sent to the red coke receiving hopper 1, due to the high temperature of the red coke, the air brought into the receiving hopper will be completely combusted, and when the piston push rod pushes the red coke into the coke quenching carbon coating trolley 6 At that time, there is no combustion-supporting oxidizing substance on the surface of red coke. The red coke enters the coke-quenching and carbon-coating trolley 6 along the inclined chute 5. During the forward running process of the coke and carbon-coating trolley 6, the red coke forms a certain accumulation height on the surface of the trolley. The coke quenching medium enters the bellows through the pipe, and escapes from the small hole of the grate bar at a certain flow rate, and enters the red coke layer accumulated on the surface of the trolley. Red coke has a developed pore structure and strong adsorption capacity. The coke quenching medium enters the interior of the red coke from the surface of the coke through flow and diffusion. Under suitable temperature conditions, concentration conditions and pressure conditions, part of the methane in the coke quenching medium begins to decompose, forming free graphitic carbon and hydrogen, wherein the free graphitic carbon begins to deposit in the pore structure of red coke, and forms a dense film layer covering the And block the outer surface of the coke and the pores of the coke to significantly reduce the reactivity of the coke and increase the strength of the metallurgical coke after the reaction. The hydrogen produced by the pyrolysis of the coke quenching medium is discharged from the gas outlet pipe 14 along with the unreacted gas. As the red coke continues to move forward with the coke carbon coating trolley 6, the cold coke quenching medium also continuously enters the bellows from the gas pipeline, and passes through the grate holes of the trolley to exchange heat with the red coke, finally reducing the temperature of the red coke. Cool down and become cold coke. The cold coke enters the receiving hopper at the rear of the trolley, passes through the water seal, and is sent out of the system by the belt conveyor 12.

The coke quenching carbon coating trolley 6 is in the sealing cover 13 as a whole, therefore, the head and tail star wheels of the driving device of the trolley are in the sealing cover 13, and the speed change mechanism is outside the sealing cover 13, and the trolley can be moved by means of pneumatic sealing. The drive shaft is completely sealed. When the coke quenching medium enters the sealing cover 13 of the trolley, the entire sealing system adopts a slight positive pressure operation, so that the phenomenon of entraining a large amount of dust in the high-temperature airflow after heat exchange is prevented.

The coke quenching medium is coke oven gas produced by a coking plant, of which the hydrogen content is 55-60%, the methane content is 22-27%, the carbon monoxide content is 7-12%, and the rest is carbon dioxide, heavy hydrocarbons, nitrogen and oxygen. The red coke coming out of the coke oven carbonization chamber at about 1000°C is sent to the red coke receiving hopper 1 through the existing conveying equipment of the coking plant. The size of the upper opening of the red coke receiving hopper 1 matches the conveying equipment, and the size of the lower opening matches the piston push rod mechanism Matching, the height of the receiving hopper is determined by the amount of pre-stored red coke. The red coke receiving hopper 1 can pre-store a part of the material to ensure the continuity of the system operation. At the same time, under the action of the high temperature of the red coke, a small amount of air brought in by the red coke burn out. The red coke falls into the piston pushing groove 3 from the lower opening of the receiving hopper under the action of gravity. The pushing groove is rectangular, and the width of the piston push rod is slightly smaller than the width of the coke quenching carbon-coating trolley 6. The height of the push rod depends on one push focus to determine. The piston push rod adopts periodic reciprocating mechanical movement, and the red coke enters the sealing system along the push groove 3 under the action of the push rod. The outlet at the end of the piston pushing groove 3 is provided with a rotary sealing baffle 4 . When the piston advances, the sealing baffle 4 is opened under the action of the thrust, and the material enters the inclined chute 5 below the pushing chute 3. At this time, the piston and red coke block the upper feeding port to prevent the coke quenching medium from escaping; when the piston retracts, The sealing baffle 4 is automatically closed due to gravity, preventing outside air from entering the coke quenching carbon plating reaction system. The outlet of the piston pushing chute 3 is connected with an inclined chute 5, the top of the inclined chute 5 is connected to the lower edge of the outlet of the pushing chute 3, and the bottom is welded on the side of the trolley retaining plate 7, 30 to 50 cm away from the trolley surface. The coke with a temperature of about 1000°C falls from the inclined chute onto the quenching carbon plating trolley 6, and a coke layer with a stacking height of 60-80 cm is formed between the baffle plates 7 of the coke quenching carbon plating trolley, and is deposited on the coke quenching carbon plating trolley. The carbon trolley 6 moves horizontally as a whole, and the coke quenching and carbon coating trolley 6 moves horizontally at a speed of 0.2m to 0.4m/min. Under this moving speed condition, there is no relative movement between coke particles, which effectively prevents the generation of coke powder. The coke oven gas enters the gas bellows through the gas inlet pipe 9, and the upper part of the gas bellows is the grate of the coke quenching and carbon-coating trolley 6. There are small holes of 1 to 3 mm on the grate of the trolley, and the small holes are along the length of the trolley. Evenly distributed in the lateral direction, one every 2 to 3 cm. The cold coke oven gas enters the coke layer along the small holes on the grate, and convective heat exchange occurs between the hot coke, and at the same time, a large amount of coke oven gas is adsorbed in the pores of the coke. In the red coke area, the methane gas in the coke oven gas decomposes under high temperature to generate free graphitic carbon and hydrogen, and the free graphitic carbon deposits in the coke pores and forms a dense carbon film. Under the action of flow, diffusion and mass transfer, hydrogen enters the gas from inside the coke, and flows out along the gas outlet pipe 14 together with the gas. Since the gas outlet pipe 14 is at the front end of the sealing cover, it is affected by the heat radiation of red coke, and the gas The temperature of the outlet pipe 14 is between 650°C and 700°C. As the coke carburizing trolley 6 continues to move forward carrying the coke, convective heat exchange occurs between the cold gas and the coke, and the temperature of the coke gradually decreases. When the temperature of the coke is lower than 750°C, the decomposition rate of methane in the coke oven gas Decrease, the interaction between coke oven gas and coke is only convective heat transfer, the coke temperature continues to decrease, and reaches the temperature required by the process at the rear of the trolley. At this time, the coke enters the cold coke receiving hopper 10, the upper part of the cold coke receiving hopper 10 is connected to the tail of the coke carbon coating trolley 6, and the lower part is immersed in water and connected to the scraper machine in the water. The cold coke is sealed by water and cooled by water. The coke temperature is further reduced, and at the same time, a large amount of water is filled in the pores of the coke to replace the coke oven gas in the pores, and the water-sealed coke is sent out of the system by a scraper machine.

According to the change of coke temperature system, the whole process can be divided into carburizing zone and dry quenching zone in the length of the trolley, and the distribution ratio of the two zones is 1:3. The gas supply system of coke oven gas can also be divided into two areas, carbon coating area and dry quenching area. Coal gas and circulating coke oven gas account for 20% and 80% of the total gas volume respectively. These two parts of gas are discharged from a gas outlet pipe 14, one part is sent to the user after cooling and dedusting, and the other part is sent back to the system by cooling and dedusting after circulation.

Claims (6)

1. a coke metallurgical carbon-coating reinforcer is characterized in that: comprise integrative sealing cover (13), quenching plating carbon chassis (6) is arranged in the seal closure (13), cover the top and be provided with gas exit pipeline (14); The front end of seal closure (13) links to each other with red burnt hopper (1), red burnt hopper (1) top and environmental communication, take over a job and fill in feeding machine (2) in the bottom, piston feeding machine (2) can be done the reciprocating machine motion in pusher groove (3), the outlet of pusher groove (3) passage is provided with sealing baffle (4), sealing baffle (4) bottom is slant chute (5), slant chute (5) is positioned at the front end top of quenching plating carbon chassis (6), the chassis face of quenching plating carbon chassis (6) is made of the castor bar, grid section has ventilative aperture, the bottom is coal gas plenum chamber (8), evenly arranges gas entry pipeline (9) in the coal gas plenum chamber (8); The tailstock below of quenching plating carbon chassis (6) is a cold burnt hopper (10), there is water sealed tank (11) cold burnt hopper (10) discharge port lower end, water sealed tank (11) is immersed under water, and constitutes seal water system with hopper, and endless belt conveyor (12) is positioned at the below of cold burnt hopper (10).

2. according to the described coke metallurgical carbon-coating reinforcer of claim 1, it is characterized in that: quenching plating carbon chassis (6) chassis face top is provided with blocking material plate (7), prevents that coke is scattered.

3. according to the described coke metallurgical carbon-coating reinforcer of claim 1, it is characterized in that: seal closure (13) is inner for pouring fireproof material, outward covered with the welding steel plate.

4. according to the described coke metallurgical carbon-coating reinforcer of claim 1, it is characterized in that: piston feeding machine (2) adopts refractory materials and Heat resisting cast steel to do and cuts somebody's hair.

5. according to the described coke metallurgical carbon-coating reinforcer of claim 1, it is characterized in that: described endless belt conveyor (12) comprises scraper conveyor with angle and drag conveyer.

6. according to the described coke metallurgical carbon-coating reinforcer of claim 1, it is characterized in that: gas exit pipeline (14) internal surface is covered with certain thickness refractory casting material.

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