Flue gas treatment system for small experimental coke oven

Abstract

The utility model discloses a flue gas treatment system for a small experimental coke oven. Comprising a raw gas combustion device connected with the experimental small coke oven, a flue gas converging pipeline connected with the raw gas combustion device, a dust removal device connected with the flue gas converging pipeline and used for removing dust impurities in flue gas, and a machine front collecting pipe connected with the dust removal device, the centrifugal fan is connected with the machine front collecting pipe; and the coke oven flue gas desulfurization and denitrification device is connected with the centrifugal fan. The treatment system for the flue gas of the small experimental coke oven can reduce the harm of harmful gas generated in the experimental process to the internal and external environments and personnel of a laboratory, is low in cost and small in design investment, and can reduce the environmental protection risk and reduce the pollution to the environment.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of biochemical waste gas treatment, specifically, the utility model relates to a kind of experimental small coke oven flue gas processing system. BACKGROUND

[0002] Small coke oven experiment is mainly used for the coking process research of coal, and the purpose is to study the production characteristics of coal gasification and coking coke and its influence on the environment by simulating the heating process of coal in coke oven. In the experiment, coal is heated to high temperature, and a certain amount of raw coal gas is released. These gases are purified and called coke oven gas. Because it is a small-scale experiment, the collection of the above-mentioned coke oven gas generally does not reach the economic scale, and if it is directly dispersed or burned, the harmful components in these coal gas or flue gas still pose a threat to the laboratory and atmospheric environment and the health of workers, so effective coal gas or flue gas treatment measures are needed. At present, the general environmental protection requirements are increasingly strict, and the direct dispersion of coke oven gas generated by laboratory small coke oven experiment is no longer allowed, so in most cases, the coke oven gas is burned to produce small coke oven flue gas with lower atmospheric environmental pollution.

[0003] Although the experimental small coke oven gas can reduce pollutant emissions after combustion, the hazards brought by small coke oven experiment flue gas cannot be ignored, such as health hazards, environmental pollution, safety hazards, etc.

[0004] Health hazards: toxic gases contained in small coke oven experiment flue gas, such as carbon monoxide, sulfur dioxide, NO X , a small amount of carbon black particles, etc., pose a serious threat to the environment and the health of workers. High concentration of carbon monoxide can cause hypoxic poisoning, carbon black particles can also cause damage to the environment and the human body, sulfur dioxide is corrosive and toxic, and can be fatal in severe cases.

[0005] Environmental pollution: untreated small coke oven flue gas is directly discharged into the air, which will cause serious environmental pollution, especially the NO X , sulfur dioxide and carbon monoxide contained therein, which will have a lasting impact on the atmospheric environment and air quality.

[0006] Safety hazards: small amount of flammable gases such as carbon monoxide in flue gas may leak and accumulate to a certain concentration during the experiment, which may also cause the risk of fire or explosion.

[0007] The treatment method of small coke oven experiment flue gas is also flexible, economical and efficient due to the small amount of flue gas generated by the experiment. Common treatment methods include: ① ventilation and local exhaust: ensure good ventilation in the experimental area, use local exhaust hood or ventilation system to quickly exhaust flue gas, and prevent harmful gas accumulation. ②Adsorption method: use activated carbon to adsorb a small amount of carbon black particles, sulfur dioxide and NOX Etc, effectively reduce the pollution of the environment. ③ Water absorption method: using water washing to remove ammonia, sulfur dioxide and other soluble gases in the flue gas, to avoid its harm to the environment and human body.

[0008] At present, the main method of experimental small coke oven flue gas treatment in the coking industry is to wash the tail gas through the water tank set in the outdoor, and then directly discharge it into the atmosphere. If not cleaned, the SO2 content of the flue gas exceeds 100mg / m 3 , far exceeding the national standard; and using clean water for cleaning, the cleaning water needs to be constantly updated, and even so, the SO2 content of the flue gas after cleaning fluctuates greatly, at the edge of unqualified 30mg / m 3 , and if the water is cleaned with alkali (at pH = 12), the effect is not good, and the SO2 content of the flue gas after cleaning is mostly more than 35mg / m 3 , the above methods cannot achieve satisfactory results.

[0009] The Chinese patent with application number 200920109908.0 discloses an experimental coke oven gas purification device, which relates to experimental coke oven gas purification equipment and gas combustion equipment. Its characteristics are that the gas generated in the experimental coke oven is cooled to remove water and tar, and then the generated gas is burned. The device is composed of a gas leading-out system, a gas condensing system, a gas combustion system, and a tar and water collector, and has the characteristics of being applicable to various experimental coke oven types, strong tar removal capacity, non-clogging of the gas pipeline, and solid and durable equipment. This method independently sets up an experimental coke oven gas treatment device, which requires a large one-time investment, and the flue gas after combustion has not been treated, which poses an environmental risk.

[0010] The Chinese patent with application number 201710196188.5 discloses a coking experimental coke oven and a coking experimental method. The coking experimental coke oven includes a coke oven support, an experimental coke oven, a pressurizing device, and a detection device. The experimental coke oven is composed of a furnace wall, a hearth, a furnace cover, a furnace bottom tray, and a heating element. The furnace bottom tray is connected to a vertical rod of the coke oven support through a rocker arm and a lifting device, and can rotate around the vertical rod under the drive of the rocker arm, and vertically lift and move under the drive of the lifting device. The pressurizing rod of the pressurizing device passes through the furnace cover to connect a pressurizing plate, which is pressed on the coal sample. The detection device includes a temperature sensor, a pressure sensor, and a displacement sensor. The top of the furnace cover of the experimental coke oven is provided with a waste gas chimney. The application of the coking experiment can perform conventional coking experiment and pressurized coking experiment, and can ensure the accuracy of the experimental coke oven in predicting the quality of coke, so that the reliability of the experimental coke oven in guiding the production coking process reaches a new height. This patent proposes a new experimental coke oven, but does not consider the environmental treatment of flue gas, and direct discharge will undoubtedly significantly increase the environmental risk and pollute the environment.

[0011] In view of the above, it is desirable to provide a treatment system for experimental small coke oven flue gas to ensure the normal development of the experiment of the experimental small coke oven, and the generated tail gas can be discharged up to the standard. Utility model content

[0012] The utility model discloses at least solve one of the technical problems existing in the prior art. To this end, the utility model provides a treatment system for experimental small coke oven flue gas, and the purpose is to reduce the cost and environmental protection risk.

[0013] In order to realize the above-mentioned purpose, the utility model adopts the technical scheme that the treatment system for experimental small coke oven flue gas includes the raw gas combustion device connected with the experimental small coke oven, the flue gas convergence pipeline connected with the raw gas combustion device, the dust removal device connected with the flue gas convergence pipeline and used for removing the dust impurity in the flue gas, the machine front manifold connected with the dust removal device, the centrifugal fan connected with the machine front manifold and the coke oven flue gas desulfurization and denitrification device connected with the centrifugal fan.

[0014] The dust removal device is provided with at least two, and all the dust removal devices are provided in parallel.

[0015] The dust removal device is provided with two.

[0016] The dust removal device is provided with a pressure transmitter in front of the dust removal device.

[0017] The machine front manifold is provided with a pressure sensor.

[0018] The dust removal device is provided with coke, and the particle size of the coke is 5-25mm.

[0019] The raw gas combustion device is provided with a pressure sensor.

[0020] The treatment system for experimental small coke oven flue gas can reduce the harm of harmful gas generated in the experiment process to the environment and personnel in and outside the laboratory, has low cost, less design investment, can reduce the environmental protection risk, and reduces the pollution to the environment. DRAWINGS

[0021] The present specification includes the following drawings, and the shown contents are as follows:

[0022] Figure 1 It is the structure schematic view of the treatment system for experimental small coke oven flue gas of the utility model;

[0023] Marked in the drawing as:

[0024] 1, experimental small coke oven;2, raw gas combustion device;3, flue gas convergence pipeline;4, dust removal device;5, machine front manifold;6, centrifugal fan;7, coke oven flue gas desulfurization and denitrification device. CONCRETE IMPLEMENTATION

[0025] The specific embodiments of the present application are further described in detail below with the description of the embodiments with reference to the accompanying drawings, the purpose of which is to help the skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical scheme of the present application, and to facilitate its implementation.

[0026] As shown in Figure 1 The utility model provides a kind of experimental small coke oven flue gas processing system, including with experimental small coke oven 1 connection's raw gas combustion device 2, with raw gas combustion device 2 connection's raw smoke gas converging pipeline 3, with raw smoke gas converging pipeline 3 connection and for removing dust impurities in smoke dust removal device 4, with dust removal device 4 connection's machine front manifold 5, with machine front manifold 5 connection's centrifugal fan 6 and with centrifugal fan 6 connection's coke oven flue gas desulfurization and denitrification device 7.

[0027] Specifically, the present application relates to a kind of coke industry experimental small coke oven generated flue gas processing system.Flue gas is by the raw gas produced by experimental small coke oven, after being flue gas by reasonable pretreatment, is sent into desulfurization and denitrification device for depth processing, it is conducive to the sustained and stable operation of system, also guarantee the quality of flue gas of external discharge atmosphere, meet environmental protection requirement.The system design is less, environmental protection, and comprehensive use effect is good.

[0028] As shown in Figure 1 Raw gas generated by experimental small coke oven 1 is first introduced into raw gas combustion device 2, and raw gas combustion device 2 is provided with multiple raw gas combustion devices 2, and the gas inlet of each raw gas combustion device 2 is connected with an experimental small coke oven 1.The gas outlet of raw gas combustion device 2 is connected with raw smoke gas converging pipeline 3.In the start-up of coking experiment of experimental small coke oven 1, the raw gas generated by experimental small coke oven 1 is introduced into raw gas combustion device 2, and the raw gas is combusted in the device to generate flue gas, and the valve on the flue gas pipeline behind raw gas combustion device 2 is opened synchronously, and the flue gas discharged after combustion of small coke oven raw gas is collected through raw smoke gas converging pipeline 3.The gas outlet of raw smoke gas converging pipeline 3 is provided with a valve, and the opening degree of the valve can be adjusted.

[0029] The above experimental small coke oven 1 can be 40 Kg, 100 Kg or 300 Kg experimental small coke oven.

[0030] As shown in Figure 1 Dust removal device 4 is provided with at least two, and all dust removal devices 4 are connected in parallel, and the gas outlet of raw smoke gas converging pipeline 3 is connected with the gas inlet of all dust removal devices 4.A small amount of carbon black particles is contained in flue gas after combustion, and the dust in the flue gas needs to be collected by dust removal device 4, and the flue gas after raw smoke gas converging pipeline 3 enters dust removal device 4, and the dust removal device 4 can effectively remove the solid carbon black and other dust impurities in the flue gas to prevent them from entering the subsequent processing link.

[0031] Furthermore, coke with a particle size of 5–25 mm is placed inside the dust removal device 4. Using coke with a particle size of 5–25 mm removes impurities from the flue gas. This allows the coke, which has adsorbed carbon black particles and a small amount of incompletely burned VOCs, to be recycled or directly used in iron pretreatment processes in the steel industry, such as sintering, facilitating processing.

[0032] like Figure 1 As shown, the outlets of all dust removal devices 4 are connected to the inlets of the pre-machine manifold 5, and the outlets of the pre-machine manifold 5 are connected to the inlets of the centrifugal fan 6, which is a variable frequency fan. The centrifugal fan 6 is used to pressurize the flue gas. After dust removal, the flue gas passes through the pre-machine manifold 5 to detect the suction force in front of the fan, and then is pressurized to 20-25 kPa (gauge pressure) by the centrifugal fan 6. This provides the necessary pressure conditions for entering the subsequent coke oven flue gas desulfurization and denitrification treatment device, thereby improving the treatment efficiency of the desulfurization and denitrification device.

[0033] like Figure 1 As shown, the outlet of the centrifugal fan 6 is connected to the inlet of the coke oven flue gas desulfurization and denitrification device 7. After being pressurized, the flue gas is transported to the coke oven flue gas desulfurization and denitrification device 7. This device adopts advanced desulfurization and denitrification technology used in industry, which can effectively remove sulfur dioxide and nitrogen oxides (such as NOx) in the flue gas, convert them into harmless gases or solids, further purify the flue gas, and reduce the impact of emissions on the environment.

[0034] For the desulfurization and denitrification device 7 for coke oven flue gas, it is recommended to use an integrated desulfurization and denitrification device using activated coke. This device can further remove carbon black particles, a small amount of tar, and a small amount of VOCs from the flue gas of the experimental small coke oven.

[0035] Preferably, a pressure transmitter is installed before the dust removal device 4 to detect the pressure of the flue gas entering the dust removal device 4, and a pressure sensor is installed on the pre-machine manifold 5 to detect the pressure of the flue gas entering the pre-machine manifold 5. The raw coal gas combustion device 2 is equipped with a pressure sensor to detect the flue gas pressure after the raw coal gas combustion device.

[0036] The flue gas treatment system of this invention can significantly reduce the concentration of harmful components in flue gas, meet environmental protection requirements, and improve the overall efficiency of flue gas treatment.

[0037] Example

[0038] like Figure 1 As shown, in this embodiment, four small coke ovens were used for coal coking experiments. Each small coke oven produced 519 m³ of flue gas during the experiment. 3 / h, the total exhaust volume of the four small coke ovens is 2076m³ / h. 3 / h. The flue gas contained 150 mg / m³ of SO2 before treatment. 3 , containing NOx 108 mg / m 3 To ensure that the flue gas emissions meet environmental standards, the laboratory designed and implemented the following flue gas treatment system.

[0039] 1. Flue gas emission and collection

[0040] At the beginning of the experiment, the flue gas pipes of the four small coke ovens were opened synchronously, and the flue gas was collected uniformly through the flue gas collection pipe. This flue gas collection system can effectively guide the flue gas to the subsequent treatment equipment.

[0041] 2. Dust collection

[0042] In this embodiment, two dust removal devices are provided. The two dust removal devices can be designed as one open and one standby for easy replacement, and a pressure transmitter is provided before each dust removal device for online detection of pressure, monitoring of pressure difference changes, and timely replacement of saturated coke after dust removal.

[0043] The flue gas first enters the dust collection device, i.e., the dust removal device, and 5-10 mm particle size coke is used in the device to adsorb solid impurities and a small amount of VOCs in the flue gas. The device uses one open and one standby for regular coke replacement, and the monitoring system monitors the pressure difference in real time to indicate when the coke needs to be replaced. In this way, the dust in the flue gas is effectively removed, providing clean flue gas for subsequent treatment.

[0044] 3. Pressurization treatment

[0045] The dust-removed flue gas is pressurized to 20 kPa by a centrifugal fan. The centrifugal fan can automatically adjust the speed according to the changes in flue gas flow and pressure to ensure stable pressure conditions for the subsequent desulfurization and denitrification device. This pressurization treatment system can adapt to the fluctuations in flue gas flow and ensure efficient operation of the system.

[0046] 4. Desulfurization and denitrification treatment

[0047] The pressurized flue gas is transported to the coke oven flue gas desulfurization and denitrification device, which uses industrial desulfurization and denitrification technology (such as chemical absorption or catalyst adsorption) to effectively remove sulfur dioxide (SO2) and nitrogen oxides (NO x ) in the flue gas. The treated flue gas meets the environmental emission standards and is discharged into the atmosphere, causing no pollution to the surrounding environment.

[0048] 5. Summary

[0049] Through this flue gas treatment system, the total exhaust gas of 2076 m 3 / h of flue gas generated by the four small coke ovens is subjected to multiple treatments such as dust collection, pressurization, desulfurization, and denitrification, and the treated SO2 is 15 mg / m 3 , and the NO x content is 50 mg / m3 The whole system is efficient and safe, can ensure that the harmful gas generated in the experiment is effectively treated, meets the environmental protection requirements, and reduces the influence on the laboratory and the surrounding environment.

[0050] The above flue gas treatment system has the following advantages:

[0051] 1. The coke is used to remove solid impurities (such as carbon black, a small amount of tar and VOCs, etc.) in flue gas, and the reuse of coke is considered. By using coke to adsorb impurities in flue gas, not only dust can be effectively removed, but also secondary pollution can be reduced. In the design, the dust removal device adopts one open and one standby, which is convenient for periodic replacement of coke. At the same time, by setting a pressure transmitter, the function of monitoring the change of pressure difference is utilized, so that the running state of the device can be monitored in real time, and the timing of replacing the coke can be prompted in time, so as to ensure the dust removal effect and system efficiency.

[0052] 2. The frequency conversion centrifugal fan is used to pressurize the flue gas to 20-25kPa (gauge pressure). Compared with the traditional fixed pressure pressurization mode, the frequency conversion centrifugal fan can automatically adjust the pressurization strength according to the change of flue gas pressure, and provide stable and adjustable pressure conditions. This design effectively stabilizes the pressure before the fan, and does not interfere with the treatment efficiency of the original desulfurization and denitrification device, ensures the full reaction and treatment of flue gas in the desulfurization and denitrification stage, reduces energy waste, and can adapt to the fluctuation of flue gas flow in the experiment.

[0053] 3. The system adopts integrated design, which ensures that each link (such as dust removal, pressurization, desulfurization and denitrification) of flue gas treatment can run coordinately, and avoids the redundancy and mismatching problem between traditional single devices. The modular design of each link (such as coke dust removal device, frequency conversion centrifugal fan, desulfurization and denitrification device, etc.) makes the system have high flexibility and expandability.

[0054] 4. The coke is replaced by monitoring the change of pressure difference in the dust removal device, which effectively ensures the long-term stable operation of the system.

[0055] 5. It is ensured that nitrogen oxides and sulfur dioxide in the flue gas of the small coke oven are removed, which overcomes the disadvantage that water washing cannot remove nitrogen oxides, and at the same time, the sulfur dioxide can be stably controlled within the standard range.

[0056] 6. Only one pipeline and fan are needed to ensure that the flue gas meets the environmental protection standard, which reduces the flue gas of the experimental small coke oven to meet the requirements under the increasingly strict environmental protection requirements, and does not need water washing, does not produce waste water and waste residue, and the less carbon particles adsorbed by coke can be directly reused. The standard of clean production is reached.

[0057] 7、The raw coal gas combustion device is provided with a pressure sensor and is adjusted by a valve, so that the raw coal gas combustion after each experimental small coke oven is in the best state, and the smoke flow and components are stable.

[0058] 8、The utility model only adopts the coke dust collector and centrifugal variable frequency fan which are common in the coking industry as the pretreatment device, directly sends the smoke to the existing coke oven flue gas desulfurization and denitrification device through a pipeline for treatment, and all expenses will not exceed 200,000 yuan; because the experimental small coke oven generates less smoke, only 500m 3 / h or so for each, compared with the coke oven flue gas desulfurization and denitrification device with the design air volume of 400000-600000m 3 / h, the smoke amount and the treatment of sulfur dioxide and NO x and other pollutants in the smoke can be almost ignored, and if the flue gas desulfurization and denitrification device for the experimental small coke oven is constructed separately, the expense needs at least 1,000,000 yuan or more for each.

[0059] The utility model is described above in combination with the drawings. Apparently, the specific implementation of the utility model is not limited by the above mode. As long as various non-essential improvements are made by adopting the method concept and technical scheme of the utility model, or the above concept and technical scheme of the utility model is directly applied to other occasions without improvement, all are within the protection scope of the utility model.

Claims

1. A system for treating experimental small-scale coke oven flue gas, characterized by: The device comprises a raw coal gas combustion device connected with an experimental small coke oven, a flue gas merging pipeline connected with the raw coal gas combustion device, a dust removal device connected with the flue gas merging pipeline and used for removing dust impurities in the flue gas, a front-end collecting pipe connected with the dust removal device, a centrifugal fan connected with the front-end collecting pipe, and a coke oven flue gas desulfurization and denitrification device connected with the centrifugal fan.

2. The system for treatment of experimental small-scale coke oven flue gas according to claim 1, characterized in that: The dust removal device is provided with at least two, and all the dust removal devices are provided in parallel.

3. The system for treatment of experimental small-scale coke oven flue gas according to claim 2, characterized in that: The dust removal device is provided with two.

4. The system for treating experimental small-scale coke oven flue gas according to any one of claims 1 to 3, characterized in that: A pressure transmitter is arranged in front of the dust removal device.

5. The system for treating experimental small-scale coke oven flue gas according to any one of claims 1 to 3, characterized in that: A pressure sensor is arranged on the front-end collecting pipe.

6. The system for treatment of experimental small-scale coke oven flue gas according to any one of claims 1 to 3, characterized in that: Coke with a particle size of 5-25 mm is arranged in the dust removal device.

7. The system for treatment of experimental small-scale coke oven flue gas according to any one of claims 1 to 3, characterized in that: The raw coal gas combustion device is provided with a pressure sensor.

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