Device for treating waste gas generated by MVR (Mechanical Vapor Recompression) system in coal tar production

Abstract

The utility model belongs to the technical field of chemical production equipment, and discloses a device for treating waste gas generated by an MVR (Mechanical Vapor Recompression) system in coal tar production, which comprises an MVR evaporation system, an oil separation tank, an oil removal tank and a negative pressure film evaporator which are sequentially communicated through pipelines and pumps, tail gas outlets of the MVR evaporation system and the negative pressure film evaporator are sequentially communicated with an absorption tower, a filter and an activated carbon adsorption box through pipelines; a tail gas outlet of the activated carbon adsorption box is respectively communicated with the combustor and the induced draft fan through pipelines, and a gas outlet of the combustor is respectively communicated with the desorption fan and the induced draft fan through pipelines; a gas outlet of the induced draft fan is communicated with a tail gas treatment system through a pipeline. The tail gas generated by the MVR evaporation system and the tail gas generated in the mother liquor treatment process can be effectively treated at the same time, the structure is simple, the treatment effect is good, and the environmental safety is ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical production equipment, and in particular relates to a waste gas treatment device generated by an MVR system in coal tar production. Background Art

[0002] Coal tar is an organic mixture mainly composed of aromatic hydrocarbons. The wastewater discharged during the deep processing of coal tar has a high concentration of pollutants and a relatively complex composition. In addition to petroleum, volatile phenols, and ammonia nitrogen, it also contains monocyclic or polycyclic aromatic compounds such as indole and quinoline, as well as heterocyclic organic pollutants containing nitrogen, sulfur, and oxygen. It is one of the more difficult wastewaters to treat; the current treatment method generally uses a water storage tank for temporary storage, followed by oil removal, MVR evaporation, iron-carbon micro-electrolysis, Fenton oxidation, and biochemical treatment; when the material is treated in the MVR evaporation system, crystalline salt, mother liquor, and process tail gas containing volatile organic compounds will be produced, of which the crystalline salt is collected and sold out to increase efficiency, and the mother liquor is discharged after treatment, but the corresponding process tail gas containing volatile organic compounds will also be produced during the treatment process. The tail gas produced in the above two places needs to be treated before it can be discharged, but no corresponding treatment device has been found in the prior art, so the above problems need to be solved urgently. Summary of the invention

[0003] The technical problem to be solved by the utility model is to provide a waste gas treatment device generated by an MVR system in coal tar production, which overcomes the defects of the prior art and can effectively treat the tail gas generated by the MVR evaporation system and the tail gas generated in the mother liquor treatment process at the same time, has a simple structure, good treatment effect, and ensures environmental safety.

[0004] In order to solve the above technical problems, the technical solution of the utility model is:

[0005] A waste gas treatment device generated by an MVR system in coal tar production comprises an MVR evaporation system, an oil separator, an oil removal tank and a negative pressure film evaporator which are sequentially connected through pipelines and pumps. The MVR evaporation system and the negative pressure film evaporator are both provided with tail gas outlets, and the tail gas outlets of the MVR evaporation system and the negative pressure film evaporator are sequentially connected to an absorption tower, a filter and an activated carbon adsorption box through pipelines; the tail gas outlet of the activated carbon adsorption box is respectively connected to a burner and an induced draft fan through pipelines, and the gas outlet of the burner is respectively connected to a desorption fan and an induced draft fan through pipelines; and the gas outlet of the induced draft fan is connected to the tail gas treatment system through a pipeline.

[0006] Preferably, the mother liquor in the grease trap is transported to the oil removal tank by a pump, and the salt particles settled in the grease trap are regularly cleaned to a salt collection tank to wait for processing.

[0007] Preferably, the oil removal tank is connected to the floating oil storage tank, and the floating oil storage tank is connected to the workshop oil device through a pipeline and a pump, so as to realize the reuse of floating oil and save energy and reduce consumption.

[0008] Preferably, the model of the negative pressure thin film evaporator is XYMNPD-200, and the manufacturer is Weifang Xinyu Environmental Engineering Co., Ltd.

[0009] Preferably, the crystallized salt outlet of the negative pressure thin film evaporator is connected to a bagging system, so that the crystallized salt can be packed into bags and then sold out, thus increasing the efficiency.

[0010] Preferably, the pipelines are all provided with steam heating and heat preservation devices, and are provided with steam purge ports, to prevent the mother liquor from cooling and crystallizing during transportation and clogging the pipelines.

[0011] Preferably, the absorption tower is an alkaline absorption tower, which can absorb acidic substances in the tail gas; the absorption tower is also connected to a temporary storage tank, which is connected to the MVR evaporation system; the filter is a dry filter,

[0012] Preferably, two activated carbon adsorption boxes are arranged in parallel; when one is shut down to desorb the activated carbon, the other can be used to ensure the continuity of production.

[0013] Preferably, a heat exchanger is provided on the pipeline between the activated carbon adsorption box and the burner to preheat the exhaust gas and then burn it.

[0014] Preferably, the exhaust gas treatment system includes a pressure regulating box, an induced draft fan, an oxidation tower, an absorption tower, a chimney and other devices which are sequentially connected through pipelines and valves.

[0015] Due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0016] The utility model first transports the mother liquor generated by the MVR evaporation system to the existing oil separator, and then transports it to the oil removal tank; realizes oil and water stratification in the oil removal tank, and the upper floating oil is regularly discharged to the floating oil storage tank, and the lower mother liquor is sent to the negative pressure film evaporator for full drying treatment; the water vapor and odor gas generated in the treatment process of the negative pressure film evaporator and the waste gas generated by the salt outlet system in the MVR evaporation system are transported to the absorption tower, the filter, and the activated carbon adsorption box for treatment, the treated gas is burned by the combustion furnace, and enters the desorption fan to desorb the activated carbon again, or enters the induced draft fan after being burned by the combustion furnace, and the gas treated by the activated carbon adsorption box can also directly enter the induced draft fan, and the induced draft fan introduces the gas into the exhaust gas treatment system for treatment, and the treated gas that meets the standards is discharged.

[0017] In conclusion, the utility model can effectively treat the tail gas generated by the MVR evaporation system and the tail gas generated in the mother liquor treatment process at the same time, has a simple structure, good treatment effect, and ensures environmental safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the process of the utility model;

[0019] In the figure, 1. MVR evaporation system; 2. Grease trap; 3. Oil removal tank; 4. Negative pressure thin film evaporator; 5. Absorption tower; 6. Filter; 7. Activated carbon adsorption box; 8. Burner; 9. Draft fan; 10. Desorption fan; 11. Exhaust gas treatment system; 12. Floating oil storage tank; 13. Bag system; 14. Temporary storage tank. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0021] Embodiment 1:

[0022] like Figure 1 As shown, a waste gas treatment device generated by an MVR system in coal tar production comprises an MVR evaporation system 1, an oil separator 2, an oil removal tank 3 and a negative pressure film evaporator 4 which are sequentially connected through pipelines and pumps, the MVR evaporation system 1 and the negative pressure film evaporator 4 are both provided with tail gas outlets, the tail gas outlets of the MVR evaporation system 1 and the negative pressure film evaporator 4 are sequentially connected to an absorption tower 5, a filter 6 and an activated carbon adsorption box 7 through pipelines; the tail gas outlet of the activated carbon adsorption box 7 is respectively connected to a burner 8 and an induced draft fan 9 through pipelines, the gas outlet of the burner 8 is respectively connected to a desorption fan 10 and an induced draft fan 9 through pipelines; the gas outlet of the induced draft fan 9 is connected to a tail gas treatment system 11 through a pipeline; the tail gas treatment system 11 comprises a pressure regulating box, an induced draft fan, an oxidation tower, an absorption tower and a chimney which are sequentially connected through pipelines and valves.

[0023] The oil removal tank 3 is connected to the floating oil storage tank 12 ; the negative pressure thin film evaporator 4 is connected to the bagging system 13 ; the absorption tower 5 is also connected to the temporary storage tank 14 , and the temporary storage tank 14 is connected to the MVR evaporation system 1 .

[0024] In actual production, the mother liquor produced by the MVR evaporation system 1 is first transported to the oil separator 2 for temporary storage. After the salt particles in the mother liquor are settled (regularly cleaned to the salt collection tank for processing), the mother liquor is pumped together with the floating oil to the oil removal tank 3; the oil and water are separated in the oil removal tank 3, the upper floating oil is regularly discharged to the floating oil storage tank 12 (then the floating oil is recycled to the corresponding equipment in the workshop), and the lower mother liquor is transported to the negative pressure thin film evaporator 4 for full drying treatment. The odorous gas containing a large amount of water vapor generated during the drying process, together with the The exhaust gas generated by the MVR evaporation system 1 is transported to the (alkali solution) absorption tower 5, and the exhaust gas is pre-treated while being cooled. The pre-treated exhaust gas is then transported to the (dry) filter 6, so that the exhaust gas must be pre-treated before entering the activated carbon adsorption box 7, and the dust particles therein are filtered out, and the droplets carried in the exhaust gas are removed, so as to improve the adsorption efficiency and extend the service life of the activated carbon; the exhaust gas after the activated carbon adsorption is transported to the exhaust gas treatment system 11 through the induced draft fan for treatment, and the treated exhaust gas meets the emission standards and is discharged;

[0025] The activated carbon in the activated carbon adsorption box 7 needs to be desorbed after being treated for a period of time to regenerate the activated carbon. At this time, the running activated carbon adsorption box 7 is turned off, and the standby activated carbon adsorption box 7 is started. At the same time, the waste gas treated by the activated carbon adsorption box 7 is burned by the burner 8 and then transported to the desorption fan 10. After adding the desorbent, the activated carbon in the activated carbon adsorption box 7 is desorbed, and the generated waste gas is burned by the burner 8 and then enters the induced draft fan 9, and then enters the exhaust gas treatment system 11 for treatment, and finally discharged.

[0026] Through the above process, the waste gas generated by the MVR evaporation system 1 is effectively treated; the treated waste gas meets the emission standards, effectively ensuring environmental safety.

[0027] It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A waste gas treatment device generated by an MVR system in coal tar production, characterized by: It comprises an MVR evaporation system, an oil separator, an oil removal tank and a negative pressure film evaporator which are sequentially connected through pipelines and pumps. The MVR evaporation system and the negative pressure film evaporator are both provided with tail gas outlets, and the tail gas outlets of the MVR evaporation system and the negative pressure film evaporator are sequentially connected to an absorption tower, a filter and an activated carbon adsorption box through pipelines; the tail gas outlet of the activated carbon adsorption box is respectively connected to a burner and an induced draft fan through pipelines, and the gas outlet of the burner is respectively connected to a desorption fan and an induced draft fan through pipelines; the gas outlet of the induced draft fan is connected to the tail gas treatment system through a pipeline.

2. The waste gas treatment device generated by the MVR system in coal tar production according to claim 1, characterized in that: The mother liquid in the grease trap is transported to the oil removal tank by a pump.

3. The waste gas treatment device generated by the MVR system in coal tar production according to claim 1, characterized in that: The oil removal tank is connected to the floating oil storage tank, and the floating oil storage tank is connected to the workshop oil device through a pipeline and a pump.

4. The waste gas treatment device generated by the MVR system in coal tar production according to claim 1, characterized in that: The crystallized salt outlet of the negative pressure thin film evaporator is connected to the bagging system.

5. The waste gas treatment device generated by the MVR system in coal tar production according to claim 1, characterized in that: The absorption tower is an alkali solution absorption tower.

6. The waste gas treatment device generated by the MVR system in coal tar production according to claim 1, characterized in that: The filter is a dry filter.

7. The waste gas treatment device generated by the MVR system in coal tar production according to claim 1, characterized in that: Two activated carbon adsorption boxes are arranged in parallel.

8. The waste gas treatment device generated by the MVR system in coal tar production according to claim 1, characterized in that: A heat exchanger is arranged on the pipeline between the activated carbon adsorption box and the burner.

9. The waste gas treatment device generated by the MVR system in coal tar production according to claim 1, characterized in that: The tail gas treatment system comprises a pressure regulating box, an induced draft fan, an oxidation tower, an absorption tower and a chimney which are sequentially connected through pipelines and valves.

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