VOCs waste gas treatment system for coking industry

Abstract

The utility model relates to the technical field of coking industry waste gas treatment, in particular to a coking industry VOCs waste gas treatment system. Comprising a waste gas buffer tank, a filter, a front induced draft fan, a pretreatment pickling tower, a pretreatment alkaline washing tower, a first gas-liquid separator, a second gas-liquid separator, a main fan, a rotary high-temperature heat storage oxidation incinerator, a quench tower, a rear induced draft fan and a chimney which are sequentially connected through pipelines. The device further comprises an activated carbon adsorption tank and a low-pressure steam desorption device, the filter, the second gas-liquid separator and the rear induced draft fan are respectively connected with the activated carbon adsorption tank through pipelines, and the activated carbon adsorption tank is connected with the low-pressure steam desorption device through a pipeline. The device is simple in structure, high in treatment efficiency, capable of effectively removing organic pollutants in waste gas and meeting the requirement for standard emission of VOCs waste gas in a chemical production area of a coking plant, and low in operation energy consumption.

Description

Technical Field

[0001] The utility model relates to the technical field of waste gas treatment in the coking industry, in particular to a VOCs waste gas treatment system in the coking industry. Background Art

[0002] In coking production, volatile organic compounds (VOCs) are generated in multiple links such as coking, quenching, and gas purification. These VOCs not only cause serious pollution to the atmospheric environment, but also endanger human health. With the increasingly stringent environmental protection requirements and people's attention to environmental quality, the demand for VOCs waste gas treatment in the coking industry has become more urgent.

[0003] However, the existing VOCs waste gas treatment technology in the coking industry has certain limitations. The treatment efficiency is low, and it cannot effectively remove organic pollutants in the waste gas. It cannot meet the demand for VOCs waste gas emissions in the coking plant production area to meet the emission standards, and the operating energy consumption is high. Utility Model Content

[0004] In order to overcome the shortcomings of the prior art, the utility model provides a coking industry VOCs waste gas treatment system. The treatment efficiency is high, and the organic pollutants in the waste gas can be effectively removed, meeting the requirements of VOCs waste gas emission standards in the coking plant production area, and the operation energy consumption is low.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A coking industry VOCs waste gas treatment system comprises a waste gas buffer tank, a filter, a front induced draft fan, a pre-treatment acid washing tower, a pre-treatment alkali washing tower, a first gas-liquid separator, a second gas-liquid separator, a main fan, a rotary high-temperature thermal storage oxidation incinerator, a quenching tower, a rear induced draft fan and a chimney which are sequentially connected through pipelines; it also comprises an activated carbon adsorption tank and a low-pressure steam desorption device, the filter, the second gas-liquid separator, and the rear induced draft fan are respectively connected to the activated carbon adsorption tank pipeline, and the activated carbon adsorption tank is connected to the low-pressure steam desorption device pipeline.

[0007] Furthermore, the pre-treatment pickling tower is a spray-type pickling tower, and the absorption liquid used is a sulfuric acid solution with a mass percentage concentration of 0.5% to 5%.

[0008] Furthermore, the pre-treatment alkali washing tower is a spray-type alkali washing tower, and the absorption liquid used is a sodium hydroxide solution with a mass percentage concentration of 30% to 40%.

[0009] Furthermore, the first gas-liquid separator and the second gas-liquid separator are both wire mesh gas-liquid separators, and a matching water storage tank is provided at the bottom.

[0010] Furthermore, at least one set of cooling spray pipes is provided in the quenching tower.

[0011] Furthermore, the activated carbon adsorption tank is provided with three inlets, which are respectively connected to the outlet of the filter, the outlet of the second gas-liquid separator, and the outlet pipe of the low-pressure steam desorption device; one outlet of the activated carbon adsorption tank is connected to the inlet pipe of the rear induced draft fan, and the other outlet of the activated carbon adsorption tank is connected to the inlet pipe of the low-pressure steam desorption device.

[0012] Furthermore, the low-pressure steam desorption device comprises a vacuum pump, a condenser, a separation cylinder and a hot air blower, and the vacuum pump and the hot air blower are connected to the activated carbon adsorption tank pipeline.

[0013] Compared with the prior art, the utility model has at least the following technical effects or advantages:

[0014] In order to improve the treatment efficiency, improve the treatment effect and reduce the operating energy consumption, the utility model adopts a combination of multiple technologies: VOCs waste gas first enters the waste gas buffer tank, and after buffering, the waste gas flow is ensured to be stable. Subsequently, the waste gas passes through the filter to remove solid particle impurities therein, and the waste gas passes through the pre-treatment acid washing tower and the pre-treatment alkali washing tower in turn, and the acidic or alkaline substances in the waste gas are removed by acid-base neutralization reaction respectively. The pre-treated waste gas enters the gas-liquid separator, and the water vapor and droplets entrained in the waste gas are removed by physical methods to ensure the high efficiency of subsequent treatment. The separated waste gas completely oxidizes and decomposes the organic matter in the waste gas at high temperature and converts it into harmless carbon dioxide and water vapor. The high-temperature gas after incineration is quickly cooled by the quenching tower to prevent the generation of secondary pollutants. Finally, the waste gas after cooling treatment is sent to the chimney by the rear induced draft fan and safely discharged into the atmosphere. When the waste gas concentration in the system is low, the waste gas discharged from the filter or the gas-liquid separator is sent to the activated carbon adsorption tank, and then sent to the chimney for discharge through the rear induced draft fan.

[0015] The utility model can meet the VOCs waste gas emission standards in the coking plant production area through multi-stage waste gas treatment, and has the advantages of high safety, stable compliance and low operating energy consumption, thus realizing green production. It can effectively remove organic pollutants in waste gas, reduce environmental pollution and ensure ecological safety. In addition, the system can also be modularly designed according to actual needs, which is easy to install and maintain, and improves the efficiency and effect of waste gas treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure and process flow chart of the utility model.

[0017] In the figure: 1-waste gas buffer tank 2-filter 3-pre-induced draft fan 4-pre-treatment acid washing tower 5-pre-treatment alkali washing tower 6-first gas-liquid separator 7-second gas-liquid separator 8-main fan 9-rotary high-temperature thermal storage oxidation incinerator (RTO) 10-quenching tower 11-rear induced draft fan 12-chimney 13-activated carbon adsorption tank 14-low-pressure steam desorption device DETAILED DESCRIPTION

[0018] The embodiments of the present invention are described in detail below. In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described in combination with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] In the description of the utility model, it should be noted that the terms used herein are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the utility model. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0022] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, the numerical expressions and numerical values ​​do not limit the scope of the utility model. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0023] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the utility model.

[0024] [Example]

[0025] like Figure 1 As shown, a coking industry VOCs waste gas treatment system includes a waste gas buffer tank 1, a filter 2, a pre-induced draft fan 3, a pre-treatment acid washing tower 4, a pre-treatment alkali washing tower 5, a first gas-liquid separator 6, a second gas-liquid separator 7, a main fan 8, a rotary high-temperature thermal storage oxidation incinerator (RTO) 9, a quenching tower 10, a post-induced draft fan 11, a chimney 12, an activated carbon adsorption tank 13 and a low-pressure steam desorption device 14.

[0026] The waste gas buffer tank 1, the filter 2, the front induced draft fan 3, the pre-treatment acid washing tower 4, the pre-treatment alkali washing tower 5, the first gas-liquid separator 6, the second gas-liquid separator 7, the main fan 8, the rotary high-temperature thermal storage oxidation incinerator (RTO) 9, the quenching tower 10, the rear induced draft fan 11 and the chimney 12 are connected in sequence by pipelines.

[0027] The outlet of the filter 2 is connected to the inlet pipe of the activated carbon adsorption tank 13, the outlet of the second gas-liquid separator 7 is connected to the inlet pipe of the activated carbon adsorption tank 13, and the outlet of the low-pressure steam desorption device 14 is connected to the inlet pipe of the activated carbon adsorption tank 13. One outlet of the activated carbon adsorption tank 13 is connected to the inlet pipe of the post-induced draft fan 11, and the other outlet of the activated adsorption tank 13 is connected to the inlet pipe of the low-pressure steam desorption device 14.

[0028] The pre-treatment pickling tower 4 is a spray-type pickling tower, and the absorption liquid used is a sulfuric acid solution with a mass percentage concentration of 0.5% to 5%.

[0029] The pre-treatment alkali washing tower 5 is a spray-type alkali washing tower, and the absorption liquid used is a sodium hydroxide solution with a mass percentage concentration of 30% to 40%.

[0030] The first gas-liquid separator 6 and the second gas-liquid separator 7 are both wire mesh type gas-liquid separators, and a matching water storage tank is provided at the bottom.

[0031] The quenching tower 10 is provided with at least one set of cooling spray pipes.

[0032] The low-pressure steam desorption device 14 includes a vacuum pump, a condenser, a separation cylinder, and a hot air blower. The vacuum pump and the hot air blower are connected to the activated carbon adsorption tank 13 through a pipeline.

[0033] The process principle and working process of the utility model are as follows:

[0034] 1) Waste gas collection: The VOCs waste gas generated by the coking industry first enters the waste gas buffer tank 1, and after buffering, the waste gas flow is ensured to be stable.

[0035] 2) Pretreatment: Subsequently, the waste gas passes through the filter 2 to remove solid particle impurities therein, and then enters the pre-induced draft fan 3. The waste gas is sent to the pre-treatment acid washing tower 4 to remove alkaline gases such as NH3, and to the pre-treatment alkali washing tower 5 to remove acidic gases such as H3S and HCN, and the acidic or alkaline substances in the waste gas are removed by acid-base neutralization reaction.

[0036] 3) Gas-liquid separation: The pre-treated waste gas enters the first gas-liquid separator 6 and the second gas-liquid separator 7, and the water vapor and liquid droplets entrained in the waste gas are removed by physical methods to ensure the high efficiency of subsequent treatment.

[0037] 4) High-temperature incineration: When the exhaust gas concentration in the system is higher than the set value, the separated exhaust gas is sent to the rotary high-temperature thermal storage oxidation incinerator (RTO) 9 through the main fan for exhaust gas purification. The exhaust gas enters the rotary high-temperature thermal storage oxidation incinerator (RTO) 9, and the organic matter in the exhaust gas is completely oxidized and decomposed at high temperature, and converted into harmless carbon dioxide and water vapor.

[0038] 5) Cooling and emission: The high-temperature gas after incineration is rapidly cooled by the quench tower 10 to prevent the generation of secondary pollutants. Finally, the waste gas after cooling is sent to the chimney 12 by the rear induced draft fan 11 and safely discharged into the atmosphere.

[0039] 6) When the exhaust gas concentration in the system is lower than the set value, the exhaust gas discharged from the filter 2 or the second gas-liquid separator 7 is sent to the activated carbon adsorption tank 13 to remove organic pollutants in the exhaust gas through the adsorption effect of the activated carbon; and then sent to the chimney 12 for discharge through the post-induced draft fan 11.

[0040] When the activated carbon is saturated with adsorption, the low-pressure steam desorption device 14 is used for desorption regeneration to restore the adsorption capacity of the activated carbon. Low-pressure steam is introduced into the activated carbon adsorption tank 13 through a vacuum pump, and the low-pressure steam desorption device 14 desorbs the saturated activated carbon under high-temperature vacuum. After desorption is completed, hot air is sent into the activated carbon adsorption tank 13 through a hot air blower to dry the desorbed activated carbon.

[0041] The utility model can meet the VOCs waste gas emission standards in the coking plant production area through multi-stage waste gas treatment, and has the advantages of high safety, stable compliance and low operating energy consumption, thus realizing green production. It can effectively remove organic pollutants in waste gas, reduce environmental pollution and ensure ecological safety. In addition, the system can also be modularly designed according to actual needs, which is easy to install and maintain, and improves the efficiency and effect of waste gas treatment.

[0042] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A coking industry VOCs waste gas treatment system, characterized by: It includes an exhaust gas buffer tank, a filter, a front induced draft fan, a pre-treatment acid washing tower, a pre-treatment alkali washing tower, a first gas-liquid separator, a second gas-liquid separator, a main fan, a rotary high-temperature thermal storage oxidation incinerator, a quenching tower, a rear induced draft fan and a chimney which are sequentially connected through pipelines; It also includes an activated carbon adsorption tank and a low-pressure steam desorption device. The filter, the second gas-liquid separator, and the post-induced draft fan are respectively connected to the activated carbon adsorption tank pipeline, and the activated carbon adsorption tank is connected to the low-pressure steam desorption device pipeline.

2. A coking industry VOCs waste gas treatment system according to claim 1, characterized in that: The pre-treatment pickling tower is a spray-type pickling tower, and the absorption liquid used is a sulfuric acid solution with a mass percentage concentration of 0.5% to 5%.

3. A coking industry VOCs waste gas treatment system according to claim 1, characterized in that: The pre-treatment alkali washing tower is a spray-type alkali washing tower, and the absorption liquid used is a sodium hydroxide solution with a mass percentage concentration of 30% to 40%.

4. A coking industry VOCs waste gas treatment system according to claim 1, characterized in that: The first gas-liquid separator and the second gas-liquid separator are both wire mesh gas-liquid separators, and a matching water storage tank is provided at the bottom.

5. A coking industry VOCs waste gas treatment system according to claim 1, characterized in that: At least one set of cooling spray pipes is arranged in the quenching tower.

6. A coking industry VOCs waste gas treatment system according to claim 1, characterized in that: The activated carbon adsorption tank is provided with three inlets, which are respectively connected to the outlet of the filter, the outlet of the second gas-liquid separator, and the outlet pipe of the low-pressure steam desorption device; one outlet of the activated carbon adsorption tank is connected to the inlet pipe of the rear induced draft fan, and the other outlet of the activated carbon adsorption tank is connected to the inlet pipe of the low-pressure steam desorption device.

7. A coking industry VOCs waste gas treatment system according to claim 1, characterized in that: The low-pressure steam desorption device comprises a vacuum pump, a condenser, a separation cylinder and a hot air blower, and the vacuum pump and the hot air blower are connected to the pipeline of the activated carbon adsorption tank.

Images