Integrated device for continuously producing formed coke and production process

Abstract

The invention discloses an integrated device for continuously producing formed coke and a production process, relates to an integrated system and process for pulverized coal pyrolysis, semi-coke forming and high-temperature carbonization, and belongs to the technical field of coal chemical industry. The device comprises a feeding and pyrolysis unit, a semicoke treatment and forming unit, a carbonization unit and a gas treatment unit which are connected in sequence, wherein the carbonization unit adopts a first-section rotary kiln and a second-section rotary kiln which are connected in series; the method comprises the following steps: quickly pyrolyzing pulverized coal into semicoke through a downer; cooling and pressing to form coal; the briquette coal is firstly subjected to primary carbonization at 400-900 DEG C in the first-section rotary kiln, and then is subjected to secondary high-temperature carbonization at 950-1300 DEG C in the second-section rotary kiln. According to the invention, efficient conversion of non-coking coal is realized through integrated design, the ratio is increased to 50% or more, the total carbonization time is shortened to 3-6 hours, the obtained formed coke product has high strength and low reactivity, various products such as metallurgical coke and foundry coke can be flexibly produced, the production cost is effectively reduced, and green and clean production is realized.

Description

Technical Field

[0001] This invention belongs to the field of coal chemical and coking technology, and relates to an apparatus and method for pulverized coal pyrolysis and semi-coke carbonization, and in particular to an integrated apparatus for continuous production of pre-coke and a method for preparing pre-coke using the apparatus. Background Technology

[0002] The blast furnace-converter long-process steelmaking technology is the mainstream technology in my country's steel production, accounting for over 80% of the industry's total capacity. In this process, coke is an indispensable raw material, and its quality directly affects the stability and energy efficiency of blast furnace operation. High-quality coking coal (such as coking coal, fat coal, coking coal, and lean coal) is a key resource for producing high-performance metallurgical coke due to its excellent caking and coking properties. However, the price of this type of coal is significantly higher than that of ordinary coal, and its blending ratio has become a major factor restricting the production costs of coking enterprises. For a long time, under a relatively extensive resource consumption model, high-quality coking coal suitable for metallurgy has become increasingly scarce, and the overall resource quality has shown a downward trend. Simply relying on increasing the proportion of high-quality coking coal to maintain coke quality not only significantly increases production costs but also hinders the sustainable utilization of my country's strategic and scarce resources.

[0003] To reduce coal blending costs, the coking industry has actively expanded its coal blending resources in recent years. The coking coal blending structure has expanded from the traditional four categories of coal (gas, fat, coke, and lean) to almost all coal types, with the introduction of non-coking coal gradually becoming a trend. However, non-coking coal generally suffers from poor caking properties and weak coking characteristics; directly blending large quantities will significantly reduce the mechanical strength and thermal properties of coke. Furthermore, some low-rank non-coking coals have a high content of alkaline minerals, which catalyze the reaction between coke and CO2, further reducing coke strength. In traditional processes, the proportion of non-coking coal is usually less than 30%. Therefore, the proportion of non-coking coal in coal blending is currently strictly limited. At the process level, existing technologies typically involve simply mixing non-coking coal with other coking coals, lacking pretreatment and conversion processes designed specifically for the characteristics of non-coking coal, further limiting its large-scale and efficient utilization.

[0004] Currently, both top-charging and tamping coke ovens, which are widely used, are intermittent production processes with low levels of automation and long production cycles. Top-charging coke ovens are highly dependent on high-quality coking coal, have a limited proportion of weakly caking coal, and involve complex blending processes that require strict control of coal type ratios and particle sizes; otherwise, coke strength may decrease. While tamping coke ovens can increase the proportion of weakly caking coal by increasing the bulk density of the charged coal, they also introduce problems such as complex coal cake tamping operations, sensitivity to moisture and susceptibility to collapse, and poor production continuity. Furthermore, tamped coke, due to its high isotropy, has poor resistance to alkali erosion and is prone to performance degradation in blast furnaces with high alkali metal loads, affecting blast furnace operation. It is worth noting that the tamping process involves a relatively high proportion of low-rank non-coking coal, but its high alkaline content further exacerbates coke quality degradation. In summary, the current process of blending non-coking coal to produce coking briquettes not only has a low proportion of non-coking coal and poor briquette quality, but also a long production cycle, typically with a coking cycle of 22-35 hours.

[0005] Therefore, developing a new coking technology that can significantly increase the proportion of non-coking coal or weakly caking coal, shorten the coking cycle, achieve continuous production, and take into account coke quality is of great significance for alleviating the shortage of high-quality coking coal resources, reducing production costs, and promoting the green and low-carbon transformation of the coking industry. Summary of the Invention

[0006] To address a series of technical bottlenecks in existing coking processes, such as high dependence on high-quality coking coal, limited proportion of non-coking coal, long production cycle (approximately 22-35 hours), inflexible coke quality control, and low automation, this invention discloses an integrated device for continuous coke production and a method for preparing coke using this device. This significantly increases the proportion of non-coking coal added, achieves continuous and efficient production, controls the production cycle within 3-6 hours, and ensures precise and controllable coke product quality to meet diverse application requirements. Simultaneously, it achieves closed-loop, automated, and clean production throughout the entire process, solving the problem of waste gas pollution.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] On the one hand, the present invention provides an integrated device for continuous production of shaped coke. This device achieves efficient conversion of non-coking coal by cleverly connecting pulverized coal pyrolysis, semi-coke cooling and forming, shaped coke carbonization, and gas purification treatment.

[0009] The device mainly includes a feeding and pyrolysis unit, a semi-coke processing and forming unit, a carbonization unit, and a gas processing unit connected in sequence.

[0010] The feeding and pyrolysis unit includes a feeding system (101) and a descending bed reactor (102). The feeding system (101) preferably uses an automatic screw feeder with a feeding capacity of 0-10 kg / h and a control accuracy of ≤±1%. The screw speed is adjusted via a frequency converter to achieve stable coal conveying. The screw feeder consists of a coal silo (volume ≥60L, equipped with a stirring system to prevent bridging), a drive unit, a screw (including a head section, middle section, and tail section), and bearings, ensuring uniform material settling at the feed inlet section and preventing agglomeration and material shoveling. The descending bed reactor (102) is the core component of the pyrolysis unit. Its reaction tube is made of 310S stainless steel, withstanding temperatures above 900℃, and internal components are installed to optimize heat and mass transfer. The reactor is equipped with an external modular open-type electric heater with a maximum heating temperature of 1100℃. It features rapid heating, good thermal stability, and low heat loss. Multi-segment temperature control is used, preferably at least 5 segments, with a temperature control accuracy of ±1℃. The descending bed height is designed to be over 4 meters to ensure that pulverized coal is fully pyrolyzed within a residence time of ≥12 seconds. The reactor operates at atmospheric pressure or slightly positive pressure (0.5-1 kPa). A nitrogen pipeline is installed at the upper end of the reaction tube; an expansion joint is installed at the lower end of the reaction tube to effectively compensate for thermal expansion stress.

[0011] The semi-coke processing and forming unit serves as a bridge between pyrolysis and carbonization. It includes a semi-coke storage tank (103), a semi-coke cooling tank (104), and a briquette forming machine (108). The semi-coke storage tank (103) is connected to the bottom of the descending bed reactor (102), and a solid-phase discharge valve is used to intercept and controllably discharge the semi-coke and pyrolysis gas. The tank is externally equipped with an electric heating jacket to maintain a tank temperature >500℃, preventing tar condensation and blockage; an internal filter is installed to perform preliminary dust removal on the generated pyrolysis gas. The semi-coke cooling tank (104) receives hot semi-coke from the storage tank, and its internal coil cooling system rapidly cools the semi-coke while simultaneously introducing nitrogen for protection to prevent oxidation; the cooling tank volume is not less than 50L. The briquette forming machine (108) receives the cooled semi-coke, mixes it with coking coal, and presses it into shape. The forming capacity is 10-100kg / batch, which can produce ellipsoidal coal balls with a diameter of φ20-40mm; the extrusion pressure of the forming wheel can reach 400kg / cm3, and the drive adopts a cycloidal pinwheel reducer to ensure forming strength.

[0012] The carbonization unit is the core of this invention. It adopts a two-stage rotary kiln design to achieve precise control of the coke carbonization process. It includes a first-stage rotary kiln (109) and a second-stage rotary kiln (110) connected in series.

[0013] The first stage rotary kiln (109) primarily functions to soften and melt briquettes at a relatively low temperature, generating a large amount of plastic material to provide sufficient binder phase for the final coke. The carbonization operating temperature is controlled between 400-900℃. The kiln rotation speed is adjustable from 0-20 r / min, and the tilt angle is adjustable from 0-15°. By adjusting the kiln rotation speed and tilt angle, the residence time of the briquettes in the kiln is controlled (≥30 minutes), with a processing capacity of 10-30 kg / h. The kiln length is ≥2m, with at least 3 temperature measuring points along the axial direction to ensure uniform temperature and sufficient carbonization. The operating pressure can be atmospheric or pressurized. This stage is equipped with nitrogen pipelines to create an inert atmosphere.

[0014] The second-stage rotary kiln (110) has its inlet directly connected to the outlet of the first-stage rotary kiln (preferably with a flexible connection) and receives the briquettes processed in the first stage. Its main function is to solidify the briquettes at high temperatures, altering the internal structure of the coke to ensure high strength and stability. The carbonization operating temperature is controlled between 950-1300℃. Parameters such as rotation speed, tilt angle, processing capacity, kiln length, and residence time requirements are referenced from the first stage to ensure stable continuous operation. The reactor material must be heat-resistant steel. This stage is equipped with nitrogen atmosphere piping to create an inert atmosphere.

[0015] The gas processing unit is responsible for recovering and purifying the volatile products generated by the entire system, achieving green production. This unit includes:

[0016] The system for processing the pyrolysis gas from the downflow bed consists of a filter, a tubular condenser (106), a gas-liquid separator (105), and a liquid collector, after the pyrolysis gas is discharged from the semi-coke storage tank (103). This process achieves the separation and quantitative collection of tar and coal gas. The separated coal gas is metered and then enters the incinerator (107) for combustion. Finally, it is condensed and filtered by activated carbon before being discharged in compliance with emission standards.

[0017] The system for treating carbonized coal gas consists of raw coal gas produced by the first and second stage rotary kilns, which are processed through their respective tar condensation and collection systems and coal gas metering and sampling systems before finally entering the incinerator after being treated by the purification system.

[0018] In addition, all process pipelines connecting heat source equipment (such as the moving bed to the semi-coke storage tank) are insulated with heating tape, which can reach temperatures of over 500°C to prevent tar condensation.

[0019] Centralized Control System: The device is equipped with a centralized control system (such as a PLC or DCS), electrically connected to the temperature, pressure, and flow sensors and actuators of each unit. This system provides a human-machine interface through configuration software, enabling: a) programmed temperature control and continuous adjustment of all heating zones; b) precise control of the gas mass flow meter via computer; c) real-time data (measured values, set values) acquisition, display, storage, and export; d) process monitoring (such as bed temperature and system pressure); e) safety interlock protection (two-level alarms for temperature and pressure, automatic shutdown of heating or feeding if limits are exceeded). The control interface integrates functions such as control flowcharts, parameter setting tables, programmed temperature rise curves, alarm windows, and historical data curves.

[0020] On the other hand, the present invention provides a method for producing briquettes from pulverized coal using the above-mentioned apparatus. This method embodies the synergy between process parameters and apparatus characteristics, and specifically includes the following steps:

[0021] (a) Pulverized coal pyrolysis: Pulverized coal (especially non-coking coals such as long-flame coal, non-caking coal, weakly caking coal, and medium-caking coal) with the required particle size is dried and then stably fed into the downward bed reactor (102) by the feeding system (101). Rapid pyrolysis is carried out at a temperature of 300-900℃ under a nitrogen atmosphere, with a residence time ≥12s, generating pyrolysis gas and semi-coke with a rich pore structure. Preferably, the pyrolysis temperature is 400-900℃, more preferably, the pyrolysis temperature is 450-700℃.

[0022] (b) Semi-coke Cooling and Forming: After being temporarily stored in the semi-coke storage tank (103), the hot semi-coke enters the semi-coke cooling tank (104) and is rapidly cooled to room temperature under nitrogen protection. The cooled semi-coke is then fed into a coal briquetting machine (108), where it is mixed with coking coal under high pressure (~400 kg / cm3) and pressed into briquettes (ellipsoidal, φ).

[0023] (20-40mm), wherein the coking coal is one or more of coking coal, gas coal, fat coal, and lean coal.

[0024] (c) First-stage carbonization (formation of semi-coke from plastic mass): The briquettes are fed into the first-stage rotary kiln (109) and carbonized in a nitrogen atmosphere at 400-900℃ for a residence time of not less than 30 minutes. The key to this stage is to precisely control the temperature within the range where a large amount of plastic mass is formed, so that the briquettes are fully softened and melted. Preferably, the first-stage carbonization temperature is 400-900℃, and more preferably, the first-stage carbonization temperature is 450-800℃.

[0025] (d) Second-stage carbonization (coking and solidification): The briquettes after the first-stage carbonization are directly fed into the second-stage rotary kiln (110) for second-stage carbonization at 950-1300℃ under an inert atmosphere, with a residence time of no less than 30 minutes. Preferably, the second-stage carbonization temperature is 1100-1250℃, and more preferably, it is 1150-1250℃. This stage aims to achieve full shrinkage, solidification, and graphitization of the briquettes to obtain the final high-strength coke. The total time of the entire carbonization process is shortened to less than 3 hours. (e) Gas treatment: All pyrolysis gas and carbonization gas generated in steps (a), (c), and (d) are introduced into the gas treatment unit for thorough purification to remove harmful substances and recover energy, ultimately achieving emission standards.

[0026] By flexibly adjusting the pyrolysis conditions in step (a), the carbonization temperature, atmosphere, and total time in steps (c) and (d), coke products that meet the requirements of different applications such as metallurgy, casting, or calcium carbide production can be produced.

[0027] Beneficial effects

[0028] Compared with the prior art, the present invention has the following significant advantages and beneficial effects:

[0029] (1) It has pioneered a new path for the high-value utilization of non-coking coal: by “rapid pyrolysis of the downflow bed”, non-coking coal is converted into low-volatile semi-coke, which fundamentally changes its physicochemical properties as the main body of the molding process, enabling it to effectively bond the plastic body in the subsequent carbonization. At the same time, the plastic body generated at a lower temperature in the first stage rotary kiln provides bonding, while the high temperature in the second stage rotary kiln achieves coking and solidification to ensure strength. This solves the core problem of low non-coking coal ratio (≤30%), and its ratio can exceed 50%. Compared with the traditional coking process that mainly relies on coking coal, it significantly reduces the cost of raw materials.

[0030] (2) A revolution in continuous and efficient coking technology has been achieved: the traditional intermittent coke oven has been upgraded to a continuous integrated device of "pyrolysis-forming-carbonization", which can shorten the total carbonization time from 22-35 hours to 3-6 hours, greatly improving production efficiency and reducing energy consumption and operating costs.

[0031] (3) Ensures the high quality and stability of coke products: The "two-stage rotary kiln" carbonization process scientifically simulates and optimizes the coke formation process. The low-temperature stage focuses on the formation of gelatinous bodies, while the high-temperature stage focuses on coking and solidification. This synergistic effect ensures that the shaped coke has high mechanical strength, low reactivity, and excellent block size uniformity, and the product quality is superior to that of traditional processes.

[0032] (4) Extremely high flexibility in production control: By independently controlling key parameters such as temperature, atmosphere, and residence time of the downward bed and each section of the rotary kiln, a single unit can flexibly switch to produce a variety of high value-added products such as metallurgical coke, foundry coke, and calcium carbide coke, which greatly enhances market adaptability and economic benefits.

[0033] (5) Achieved green and clean production throughout the entire process: The entire system operates in a closed manner, and all waste gas is treated by a highly efficient and unified purification system before being discharged, which completely solves the problem of serious environmental pollution in traditional coking and meets the requirements of strict environmental protection regulations.

[0034] (6) High degree of automation and safety and reliability: The integrated advanced centralized control system realizes precise automatic control and safety interlock protection of the entire process, reduces the intensity and risk of manual operation, and ensures the stability and safety of the production process.

[0035] This invention provides a complete set of technical equipment and process solutions for the efficient, clean, and high-value conversion of low-rank coal and non-coking coal, which has profound significance for promoting technological progress and sustainable development in the coking industry. Attached Figure Description

[0036] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0037] Figure 1 This is a process flow diagram of the integrated device for continuous coke production according to the present invention.

[0038] The numbers in the diagram are: 101, Feeding system; 102, Downward-flowing bed reactor; 103, Semi-coke storage tank; 104, Semi-coke cooling and collection tank; 105, Gas-liquid separator; 106, Condenser; 107, Incinerator; 108, Coal briquette forming machine; 109, First stage rotary kiln; 110, Second stage rotary kiln. Detailed Implementation

[0039] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings and examples. These examples are for further illustration and explanation only, and are not intended to limit the scope of protection of the present invention. Those skilled in the art, after understanding the technical solutions and spirit of the present invention, can make various equivalent modifications or substitutions, all of which will fall within the scope defined by the claims of the present invention.

[0040] In the embodiments of this invention, experimental methods without specific conditions are generally performed according to conventional methods in the art or conditions recommended by equipment manufacturers. Unless otherwise specified, the raw materials and equipment used are all commercially available conventional products.

[0041] Example 1:

[0042] This embodiment uses the apparatus and method described in this invention to produce metallurgical coke from long-flame coal in a certain area.

[0043] 1. Raw material preparation:

[0044] The pulverized coal used is long-flame coal, and the coking coal is a blend of coking coal, fat coal, and lean coal in a ratio of 25:20:5. The long-flame coal is crushed and ground into pulverized coal with a particle size of less than 1 mm, and then dried until the moisture content is below 2% for later use.

[0045] 2. Pyrolysis process:

[0046] The dried pulverized coal is fed into the hopper (60L) of the feeding system (101), and the agitator is started to prevent bridging. The system is first purged with nitrogen to replace the air. Then, the automatic screw feeder is started to feed the pulverized coal into the descending bed reactor (102) at a rate of 8 kg / h. Nitrogen is used as the carrier gas. The descending bed reactor adopts a five-stage programmed temperature control, with the temperature of each zone set at 600℃, 700℃, 750℃, 700℃, and 650℃, respectively. The residence time of the pulverized coal in the reactor is approximately 15 seconds. The pyrolysis gas and semi-coke produced by the reaction enter the semi-coke storage tank (103).

[0047] 3. Semi-coke processing and shaping:

[0048] The temperature of the external electric heating jacket of the semi-coke storage tank (103) is maintained at 550℃. The hot semi-coke is temporarily stored in the storage tank and undergoes preliminary dust removal via an internal filter before entering the semi-coke cooling tank (104) through the discharge valve. Cooling water is continuously circulated through the coils in the cooling tank, and nitrogen gas is continuously supplied for protection, cooling the semi-coke to below 50℃. The cooled semi-coke is then fed into the briquette forming machine (108) at 400 kg / cm³. 3 Under pressure, it is pressed into ellipsoidal coal with a diameter of about 30mm by a 1:1 ratio with coking coal, fat coal and lean coal.

[0049] 4. Carbonization process:

[0050] The formed briquettes are conveyed in a sealed manner to the hopper of the first-stage rotary kiln (109). After the system is purged with nitrogen, the rotary kiln is started. The first-stage rotary kiln (109) is set to a temperature of 750°C, a kiln speed of 5 r / min, and an inclination angle of 5°, and nitrogen is introduced as a protective atmosphere. The briquettes remain in this stage for approximately 1.5 hours to allow them to soften fully and produce a gel-like substance.

[0051] Subsequently, the briquettes are directly fed into the second-stage rotary kiln (110) via a flexible connection. The second-stage rotary kiln (110) is set at a temperature of 1150℃, with the same rotation speed and tilt angle as the first stage, and is purged with nitrogen. The briquettes remain in this high-temperature section for approximately 1.5 hours to allow for thorough coking and solidification. The total carbonization time is approximately 3 hours.

[0052] 5. Gas processing:

[0053] The pyrolysis gas generated by the downward bed pyrolysis is discharged from the semi-coke storage tank (103), first passing through a cyclone dust collector to remove particles, and then entering a shell-and-tube condenser (106) (coolant temperature set at 5℃) to condense and separate tar and water. The condensate enters a gas-liquid separator (105) for collection. The separated non-condensable gas is metered by a flow meter and then sent to the incinerator (107) (temperature 850℃) along with the carbonized coal gas generated by the two rotary kilns for combustion. Finally, it is discharged after passing through a secondary condenser and an activated carbon adsorption tank to meet emission standards. The raw coal gas generated by the two rotary kilns first recovers tar in their respective independent shell-and-tube condensers before being merged into the main pipeline to the incineration system.

[0054] 6. Results and Product Analysis:

[0055] The final coke product exhibits uniform particle size and high mechanical strength. Testing revealed that its shatter resistance (M...)... 40 The wear resistance is 92%, and the abrasion resistance (M) is 92%. 10 The proportion of long-flame coal is 5.5%, and the post-reaction strength (CSR) is as high as 68%. Throughout the process, the proportion of long-flame coal is as high as 50%, significantly reducing raw material costs. The entire production cycle takes only about 3 hours, far exceeding the production efficiency of traditional processes. Gas emissions meet environmental standards.

[0056] Example 2: Flexible Production of Foundry Coke

[0057] This embodiment demonstrates the flexibility of producing foundry coke by adjusting process parameters using the same set of equipment.

[0058] The implementation method is basically the same as that of Example 1, with the only difference being the following key parameters:

[0059] Pyrolysis temperature: The controlled temperature of the downward bed reactor (102) is increased to make the temperature of the reaction zone about 850℃.

[0060] Carbonization regime: The temperature of the first stage rotary kiln (109) is increased to 900℃, the temperature of the second stage rotary kiln (110) is increased to 1250℃, and the total carbonization time is extended to about 6 hours.

[0061] Results: The obtained coke product has a dense structure and large block size. Its microstructure is more in line with the requirements of high-quality casting coke and can be used in the precision casting industry.

[0062] Example 3

[0063] The implementation method is basically the same as that of Example 1, with the only difference being the following key parameters:

[0064] The pulverized coal used is non-caking coal, and the coking coal is prepared by blending coking coal, gas coal, fat coal, and lean coal in a ratio of 15:10:20:5. In the briquette forming machine (108), pulverized coal accounts for 30% of the total coal quantity.

[0065] Pyrolysis temperature: The control temperature of the downward bed reactor (102) is increased to make the temperature of the reaction zone about 300℃.

[0066] Carbonization regime: The temperature of the first stage rotary kiln (109) is increased to 400℃, the temperature of the second stage rotary kiln (110) is increased to 1050℃, and the total carbonization time is extended to about 5 hours.

[0067] Example 4

[0068] The implementation method is basically the same as that of Example 1, with the only difference being the following key parameters:

[0069] The pulverized coal is weakly caking coal, and the coking coal is prepared by blending coking coal, gas coal and fat coal in a ratio of 15:20:5. In the coal briquetting machine (108), pulverized coal accounts for 40% of the total coal.

[0070] Pyrolysis temperature: The controlled temperature of the downward bed reactor (102) is increased to make the temperature of the reaction zone about 900℃.

[0071] Carbonization regime: The temperature of the first stage rotary kiln (109) is increased to 1000℃, the temperature of the second stage rotary kiln (110) is increased to 1300℃, and the total carbonization time is extended to about 6 hours.

[0072] Example 5

[0073] The implementation method is basically the same as that of Example 1, with the only difference being the following key parameters:

[0074] The pulverized coal is weakly caking coal, and the coking coal is prepared by blending coking coal and fat coal in a ratio of 15:20. In the coal briquetting machine (108), pulverized coal accounts for 45% of the total coal quantity.

[0075] Pyrolysis temperature: The controlled temperature of the downward bed reactor (102) is increased to make the temperature of the reaction zone about 700℃.

[0076] Carbonization regime: The temperature of the first stage rotary kiln (109) is increased to 900℃, and the temperature of the second stage rotary kiln (110) is increased to 1200℃, with the total carbonization time extended to about 4 hours.

[0077] Example 6

[0078] The implementation method is basically the same as that of Example 1, with the only difference being the following key parameters:

[0079] The pulverized coal is weakly caking coal, and the coking coal is coking coal. Pulverized coal accounts for 48% of the total coal in the coal briquetting machine (108).

[0080] Pyrolysis temperature: The controlled temperature of the downward bed reactor (102) is increased to make the temperature of the reaction zone about 600℃.

[0081] Carbonization regime: The temperature of the first stage rotary kiln (109) is increased to 800℃, and the temperature of the second stage rotary kiln (110) is increased to 1250℃, with the total carbonization time extended to about 3 hours.

[0082] Example 7

[0083] The implementation method is basically the same as that of Example 1, with the only difference being the following key parameters:

[0084] Pyrolysis temperature: The control temperature of the downward bed reactor (102) is increased to make the temperature of the reaction zone about 450℃.

[0085] Carbonization regime: The temperature of the first stage rotary kiln (109) is increased to 450°C, and the temperature of the second stage rotary kiln (110) is increased to 1100°C, with the total carbonization time extended to about 4 hours.

[0086] Comparative Example 1: Traditional Coal Blending Process

[0087] The same long-flame coal and coking coal as in Example 1 were used, and coking was carried out using a traditional top-charging coking process. The coking cycle was 28 hours.

[0088] Result: The M of the obtained coke 40 It is 88%, M 10 The content is 7.0%, and the CSR is 62%. Moreover, due to the inclusion of 80% high-priced, high-quality coking coal, the raw material cost is much higher than that of Example 1 of this invention.

[0089] Comparative Example 2: Rotary Kiln with Only One Section

[0090] This embodiment demonstrates the flexibility of producing foundry coke by adjusting process parameters using the same set of equipment.

[0091] The implementation method is basically the same as that in Example 2, except for the following key parameters: only one section of rotary kiln was used for carbonization at 1150°C. The results showed that the coke had many cracks and poor strength, and the coking cycle was 6 hours.

[0092]

[0093] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings and examples. These examples are for further illustration and explanation only, and are not intended to limit the scope of protection of the present invention. Those skilled in the art, after understanding the technical solutions and spirit of the present invention, can make various equivalent modifications or substitutions, all of which will fall within the scope defined by the claims of the present invention.

[0094] In the embodiments of this invention, experimental methods without specific conditions are generally performed according to conventional methods in the art or conditions recommended by equipment manufacturers. Unless otherwise specified, the raw materials and equipment used are all commercially available conventional products.

Claims

1. An integrated device and production process for continuous production of coke, characterized in that, comprises, in sequence: a feed and pyrolysis unit comprising a feed system (101) for feeding pulverized coal and a down-flow bed reactor (102) for rapid pyrolysis of the pulverized coal; a semi-coke processing and briquetting unit comprising a semi-coke storage tank (103) in communication with the outlet of the down-flow bed reactor (102), a semi-coke cooling tank (104) for cooling the semi-coke, and a briquette forming machine (108) for mixing and pressing the cooled semi-coke with coking coal to form briquettes; a carbonization unit comprising at least one stage of rotary kiln furnaces for staged carbonization of the briquettes; and a gas processing unit for separating, purifying and processing the gases produced during the pyrolysis and carbonization processes. The carbonization unit comprises a first stage of rotary kiln furnaces (109) and a second stage of rotary kiln furnaces (110) connected in series, the first stage of rotary kiln furnaces (109) being used to operate at a temperature of 400-900℃ to promote the production of plastids from the briquettes, and the second stage of rotary kiln furnaces (110) being used to operate at a temperature of 950-1300℃ to coke and solidify the briquettes.

2. The apparatus of claim 1, wherein, The down-flow bed reactor (102) operates at a temperature of 300-900℃, and the residence time of the coal powder is ≥12s.

3. The apparatus of claim 1, wherein, The semi-coke storage tank (103) is provided with an electric heating device outside to maintain the tank temperature >500℃, and is provided with a filter inside; the semi-coke cooling tank (104) is provided with a coil cooling system inside and is protected by nitrogen.

4. The apparatus of claim 1, wherein, The gas processing unit comprises: a gas-liquid separator (105), a condenser (106) and a collector for collecting liquid in communication with the semi-coke storage tank (103); a tar condensation and collection system and a coal gas purification system in communication with the outlet of the carbonization unit; and a incinerator (107) for processing the tail gas after purification.

5. The apparatus of claim 1, wherein, The first stage of rotary kiln furnaces (109) and the second stage of rotary kiln furnaces (110) are each provided with a pipeline for nitrogen.

6. A method for producing a type coke by pyrolysis of pulverized coal using the apparatus according to any one of claims 1 to 5, characterized by, comprises the following steps: (a) feeding pulverized coal into the down-flow bed reactor (102) for rapid pyrolysis to obtain pyrolysis gas and semi-coke; (b) cooling the semi-coke obtained in step (a) and feeding it into the briquette forming machine (108) to mix and press it with coking coal to form briquettes; (c) feeding the briquettes obtained in step (b) into the first stage of rotary kiln furnaces (109) for first stage carbonization at a temperature of 400-900℃ in an inert atmosphere; (d) feeding the briquettes after first stage carbonization into the second stage of rotary kiln furnaces (110) for second stage carbonization at a temperature of 950-1300℃ in an inert atmosphere to coke and solidify the briquettes to obtain briquetted coke products; wherein the pyrolysis gas produced in step (a) and the carbonization gas produced in steps (c) and (d) enter the gas processing unit for recovery and purification treatment.

7. The method of claim 6, wherein, In step (a), the pulverized coal is one or more of long flame coal, non-caking coal, weakly caking coal and medium caking coal, and the ratio of the total coal is 30-50%; the pyrolysis atmosphere is a nitrogen atmosphere; the pyrolysis temperature is 300-900℃; and the coking coal is one or more of coking coal, gas coal, fat coal and lean coal.

8. The method of claim 7, wherein, In step (a), the pyrolysis temperature is 450-700℃.

9. The method of claim 8, wherein, In step (c), the temperature of the first carbonization is controlled at 400-900℃, and the residence time is not less than 30 minutes; in step (d), the temperature of the second carbonization is controlled at 950-1300℃, and the residence time is not less than 30 minutes; the total carbonization time is 3-6 hours.

10. The method of claim 9, wherein, In step (a), the pyrolysis temperature is 500-600℃; in step (c), the temperature of the first carbonization is controlled at 450-800℃; in step (d), the temperature of the second carbonization is controlled at 1150-1250℃.

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