CN215085995U

CN215085995U - VOCs exhaust-gas treatment system

Info

Publication number: CN215085995U
Application number: CN202120498180.6U
Authority: CN
Inventors: 李宇展; 赵旭; 王�华; 范江峰
Original assignee: Beijing Huatai Technology Co ltd
Current assignee: Beijing Huatai Technology Co ltd
Priority date: 2021-03-09
Filing date: 2021-03-09
Publication date: 2021-12-10
Anticipated expiration: 2031-03-09

Abstract

The utility model relates to the technical field of waste gas treatment, in particular to a VOCs waste gas treatment system, which comprises a gas generating device, a gas purifying device, a gas detecting device and a gas recovering device, wherein the gas generating device, the gas purifying device and the gas recovering device are sequentially connected along the direction of a wind channel; the gas detection device is respectively connected with the inlet and the outlet of the gas purification device. The VOCs waste gas treatment system has the characteristics of reliable performance evaluation, accurate data, no pollution, capability of evaluating various treatment technologies and the like.

Description

VOCs exhaust-gas treatment system

Technical Field

The utility model belongs to the technical field of the exhaust-gas treatment technique and specifically relates to a VOCs exhaust-gas treatment system.

Background

Volatile Organic Compounds (VOCs) as ozone and PM_2.5The important precursor is one of the main sources of the current air pollution in China. VOCs and formed secondary pollutants can have great negative effects on human health and living environment, and the VOCs are treated as the first major thing in the aspect of environmental protection by ecological environment departments of national governments and local governments at all levels. The VOCs are various in kind, and mainly include aliphatic and aromatic alkanes, alkenes, oxygen-containing hydrocarbons, halogenated hydrocarbons, and the like. Among them, n-hexane, heptane and octane affect the central nervous system of human, and polycyclic aromatic hydrocarbons and chlorinated organic compounds have carcinogenic, teratogenic and mutagenic properties. Benzene series pollutants have the characteristics of large discharge amount, wide pollution area, difficult degradation and the like, and cause serious harm to human health and environment, so that the treatment and the standard discharge of VOCs are imperative.

Compared with the common flue gas treatment, the types of pollutants discharged by the VOCs are multiple, the related discharge sources are multiple, the specific working conditions are complex and changeable, and the like, so that the characteristics of the types, the concentrations, the humidity, whether dust is contained, the oil is contained, whether intermittent discharge is generated and the like of the VOCs waste gas generated by different industries or different processes in the same industry have certain differences, and the treatment technology of the VOCs and the treatment mode of the VOCs with which configuration are adopted for carrying out waste gas treatment are of great importance. Each VOCs treatment technology has specific application boundary conditions, and how to utilize the VOCs treatment technology and compare the purification treatment efficiency of VOCs of different treatment technologies under specific conditions is necessary, so that the VOCs waste gas treatment system is established to evaluate VOCs waste gas under specific conditions, the purification treatment efficiency of different treatment technologies under the same conditions is investigated, and basic engineering data and theoretical support are provided for technical schemes and engineering design.

At present, the treatment technology aiming at industrial waste gas mainly comprises a physical method, a chemical method and a biological method, and comprises treatment means such as an adsorption technology, an absorption technology, a direct combustion technology, a catalytic combustion technology, a biological filter technology and the like. At the present stage, the treatment technology of VOCs waste gas mainly comprises the following steps: direct combustion technology, catalytic combustion technology, absorption technology, low-temperature plasma technology, photolysis technology, photocatalytic technology, activated carbon adsorption technology and the like.

The treatment technology of VOCs waste gas and its advantages and disadvantages are as follows: 1) the direct combustion technology comprises the following steps: directly burning the organic waste gas by a high-temperature heating method to achieve the purpose of waste gas purification; the advantages are that: the purification efficiency is high and can reach more than 95 percent; the disadvantages are as follows: a large amount of energy is consumed, particularly in the case of low concentration of waste gas, i.e. low combustion heat value, a large amount of fuel needs to be supplemented, and NO is easily generated at high temperature_XAnd dioxin, etc., cause secondary pollution. 2) Catalytic combustion technology: the catalyst is utilized to change the reaction path and the reaction activation energy, reduce the combustion temperature, reduce the energy consumption and achieve the aim of purifying the waste gas; the disadvantages are as follows: the catalyst has harsh use conditions, easy catalyst poisoning and slightly high price; when in use, the pretreatment is very important. 3) Absorption technology: the absorption liquid is contacted with the waste gas, so that the harmful substances in the waste gas are dissolved in the absorption liquid, and the waste gas is purified. The absorption solution is treated separately. The advantages are that: the investment is small, the operation cost is low, and the operation is simple. The disadvantages are as follows: the treatment efficiency is low, the treatment is unstable, the purification efficiency is not high, about 50 percent, the relevant environmental protection requirements are difficult to meet, a large amount of waste water and waste liquid are generated and need to be treated, and secondary pollution and the like are easy to occur. 4) Low-temperature plasma technology: the plasma is a fourth state except for a solid state, a liquid state and a gaseous state in which the substance exists, and has electrical neutrality and high conductivity at a macroscopic level. The plasma contains a large number of active electrons, ions, excited particles, photons, and the like. The result of the collision of these active particles with gas molecules isGenerate a large amount of free radicals O, OH and HO with strong oxidizing property₂And highly oxidizing O₃(ii) a Organic molecules are impacted by high-energy electrons, excited and broken by atomic bonds to form small fragment groups or atoms; o, OH, HO₂、O₃Etc. react with excited atoms, organic molecules, radicals, free radicals, etc. to finally oxidize and degrade the organic molecules into CO and CO₂And H₂And O. The advantages are that: the method is wide in applicability, suitable for treating harmful gases with low concentration (1-100 ppm) and high toxicity and odor, fills the blank that other technologies cannot treat the harmful gases, and is simple to operate. The disadvantages are as follows: the independent low-temperature plasma technology is still a place with defects when harmful waste gas is treated, and if the harmful waste gas cannot be completely and thoroughly converted into harmless gas, a plurality of byproducts are generated; the low-temperature plasma generates a large amount of ozone, and the concentration of the ozone is improperly controlled, so that the health problem of people can be caused; the energy consumption is high; lower removal efficiency, etc. 5) The adsorption technology comprises the following steps: organic gas molecules are adsorbed and fixed in pores of the porous active carbon, zeolite, diatomite, anthracite and other molecular-level large-surface residual energy, so that the organic gas is purified. The advantages are that: high treatment efficiency, wide application, simple operation, low investment cost and relatively low operation cost. The disadvantages are as follows: the air pressure loss of the system is large, the saturation point of the adsorbent is difficult to master, and the capacity of the adsorbent is limited; the adsorption purification method based on an adsorbent such as activated carbon involves problems such as activation treatment after saturation of the adsorbent and the susceptibility to secondary pollution. 6) The photocatalysis technology comprises the following steps: irradiating photocatalyst with ultraviolet light, and oxidizing various VOCs and foreign odor into harmless CO by using strong oxidizing property of generated hydroxyl free radicals and oxygen anions₂And H₂And O, achieving the purpose of decomposing harmful organic matters. The advantages are that: the oxidation capability is strong, the method belongs to normal-temperature oxidation, no secondary pollution is caused, the use is safe, and the operation is simple and convenient; the disadvantages are as follows: the method can not treat the waste gas with high concentration, and has lower relative purification efficiency.

At present, the current situation of domestic VOCs treatment is relatively disordered, laboratories of scientific research institutions usually carry out in small reactors, the flow is controlled to be 0.1-1.0L/min, although gas generating devices are relatively accurate and are detectedThe measuring instrument is advanced, but the difference between the experimental specification and the actual working condition is large, so that the measuring instrument cannot be used for the guidance basis and the design data of engineering tests. Further scale-up tests are required if necessary to properly guide the actual engineering. Company level engineering experiments, even the experimental specification can reach 1000-3000m³However, the gas distribution system of the gas generating device is relatively simple, the concentration of the gas and the proportion of different gas concentrations are greatly influenced by the environment, the gas distribution system is unstable and fluctuates greatly, the temperature and the humidity are difficult to control accurately, and the stable state is difficult to maintain, so that relatively accurate test data are obtained. Meanwhile, the test instrument has great limitations, such as low accuracy, non-standard test method, and the like, and cannot accurately detect the concentration change of the inlet and the outlet and the purification efficiency of the purification equipment. In addition, in many cases, some small and medium-sized enterprises often adopt some low-efficiency treatment technologies, or the treatment technologies have no problems, but the use conditions exceed the boundary conditions and the use range of the treatment technologies, so that the advantages of the treatment technologies cannot be fully exerted. Various treatment technologies have certain advantages and disadvantages, so an evaluation system of VOCs gas needs to be established to check and evaluate the advancement and reliability of the treatment technologies and equipment.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to solve the not enough of prior art, provide a VOCs exhaust-gas treatment system. The VOCs treatment system has the characteristics of reliable performance evaluation, accurate data, no pollution, capability of evaluating various treatment technologies and the like.

The utility model discloses a concrete technical scheme as follows:

the utility model provides a VOCs waste gas treatment system, which comprises a gas generating device, a gas purifying device, a gas detecting device and a gas recovering device, wherein the gas generating device, the gas purifying device and the gas recovering device are sequentially connected along the direction of a wind channel; the gas detection device is respectively connected with the inlet and the outlet of the gas purification device.

Preferably, the exhaust gas treatment system further comprises a gas mixing device, a gas inlet of the gas mixing device is connected with a gas outlet of the gas generating device, and a gas outlet of the gas mixing device is connected with a gas inlet of the gas purifying device.

Preferably, the exhaust gas treatment system further comprises a monitoring control device, and the monitoring control device is respectively arranged at the inlet end and the exhaust gas outlet end of the gas purification device.

Preferably, the waste gas treatment system further comprises a fan, and the fan is connected with the gas outlet of the gas recovery device.

Preferably, the gas purification device comprises a single purification device and/or a composite purification device,

the single purification device comprises one or more than two of a catalytic combustion device, a plasma purification device, an activated carbon adsorption device, a microwave resonance device and a biological purification device;

the composite purification device comprises one or more than two of photolysis + photocatalysis combination, zeolite rotating wheel + TO combination, zeolite rotating wheel + CO combination, zeolite rotating wheel + condensation recovery combination, fixed bed adsorption + CO combination, fluidized bed adsorption + CO combination and adsorption + condensation combination.

Preferably, the gas recovery device is a fluidized bed type activated carbon adsorption device or a fixed type activated carbon adsorption device.

The device in the utility model belongs to prior art, does not relate to the improvement of method.

Compared with the prior art, the utility model beneficial effect be:

1) all the purification equipment devices, including the purification equipment device of single technology and the purification equipment device of composite technology, operate and detect under the same condition, and objective, accurate and scientific detection data can be obtained;

2) most data are sampled and analyzed in a fixed mode, so that the influence of differential operation and on-site complex conditions of sampling workers on the analysis result is avoided, and larger fluctuation and deviation always exist;

3) the detection instrument is fixed, and can be selected to have higher precision and more reliability, such as GCMS; for some substances which are not suitable for GCMS test, the national specified test standard is adopted, and the test equipment and means are relatively accurate;

4) the purification efficiency of all purification equipment under limited conditions can be calculated, and the problem of fish and dragon mixing in the prior art and equipment is solved;

5) mastering the use conditions and engineering data of all the purifying devices, establishing an engineering application design database and providing theoretical support for the design of specific working conditions.

6) The gas distribution device is accurate and can quantitatively generate one or more than two gas mixtures;

7) the modular design, the equipment combination mode has diversity, and the device is suitable for evaluation of various purification equipment;

8) the gas recovery device is arranged in the system, so that incompletely purified gas can be adsorbed and recovered, and the environment can not be polluted.

Drawings

FIG. 1 is a schematic view of the VOCs waste gas treatment system of the present invention;

FIG. 2 is a schematic view of the process flow of the gas generator of the present invention;

Detailed Description

The invention will be further described with reference to the following specific embodiments and the accompanying drawings.

The utility model discloses VOCs exhaust-gas treatment system includes gas generator, gaseous purifier, gaseous detection device and gas recovery device etc. and its process flow schematic diagram is shown in FIG. 1. As can be seen from fig. 1: the process flow diagram shows the components of the treatment system, including a gas generation device, a gas purification device, a gas detection device, a gas recovery device, etc. The process flow covers the whole flow from gas generation to gas recovery relatively comprehensively. Even in the experimental process, the purification equipment has low treatment efficiency on the conditions of set gas concentration, gas composition, temperature and humidity and the like, and can not release unpurified gas and possible intermediate products into indoor air or outdoor atmosphere, so that no pollutant is discharged in the whole experimental process, and the indoor environment and the surrounding environment can be kept to meet the requirements of life and work.

The utility model discloses a gas distribution system's gas generator as follows: a quantitative pump with variable frequency and speed regulation is adopted to generate a certain amount of solvent, then the solvent is gasified through a heating system, atomized into gas with a certain concentration through a nozzle, and enters a mixing chamber to be subjected to gas purification and evaluation. The gas generating device of the gas distribution system can be one gas or a mixed gas of a plurality of gases. The solvent is stored in a storage tank, continuously sprayed out by a quantitative pump, then heated and finally atomized into gas by a nozzle. In order to make the gas mixing more uniform, the atomized gas enters the mixing box to be further uniformly mixed. The volume of the main quantitative pump for controlling the gas concentration is controlled, and the liquid usually selected has the characteristics of higher vapor pressure, easiness in gasification and the like. The gas entering the mixing chamber can be heated and gasified by the water vapor besides the gas to be detected, and then enters the mixing chamber, so that the single gas or the mixed gas has certain humidity; meanwhile, the mixed gas can be diluted to reach the standard of a certain concentration, as shown in fig. 2.

The gas purification device can be a single treatment technology or a composite treatment technology. The single treatment device comprises a catalytic combustion device, a plasma purification device, an activated carbon adsorption device, a microwave resonance device or a biological purification device and the like; the composite treatment device can be a photolysis photocatalysis device, a zeolite rotating wheel + TO, a zeolite rotating wheel + CO, a zeolite rotating wheel and other treatment technologies. And selecting a proper treatment technology for evaluation according to the type of the gas to be treated, wherein the evaluation range comprises the concentration of an inlet and an outlet, the purification efficiency, possible secondary pollutants and the like. Simulating the same working condition to be treated, treating by adopting a single treatment technology or a composite treatment technology, comparing the treatment efficiency of different treatment technologies, and giving the quality of the treatment technology under a specific condition. The equipment for the laboratory treatment technology is not too large, and the treatment air quantity is controlled to be 1000-3000m³Is between/h. The utility model discloses a combination form of administering technique more than one kind or two kinds carries out the performance evaluation to the single gas or the gaseous mist of multiple that gas generator produced to exit to the clarification plant who administers technique and carries out gas collection and detect, calculates clarification plant's net at lastThe efficiency is improved.

VOCs administers and belongs to the environmental protection field, when VOCs technique detects and handles, when VOCs administers the technique and can not satisfy the specific condition that needs were administered sometimes, will have partial volatile organic compounds to discharge, so when establishing VOCs processing system, volatile organic compounds recovery system has been designed, adsorb the incomplete gas of single administration technique or compound administration technique purification, avoid gas to discharge to cause the pollution and the healthy harm of experiment operating personnel to the atmosphere to the surrounding environment. The gas recovery device can adopt a fluidized bed type active carbon adsorption device or a fixed type active carbon adsorption device. For a fixed activated carbon adsorption device, the design is carried out according to multiple layers of activated carbon, the resistance of waste gas passing through the activated carbon is reduced, and the wind speed is controlled to be 0.3-0.4 m/s. The activated carbon box can preferably select high-quality activated carbon, ensures that the activated carbon has high specific surface area, has good proportion distribution of micropores, small pores and mesopores in the activated carbon, has large adsorption capacity and has broad-spectrum applicability to volatile organic compounds.

The VOCs gas detection system mainly adopts GC-MS for analysis and evaluation. However, if some volatile organic compounds need to be detected by a physical or chemical method, detection methods required by national standards can be adopted to ensure the correctness and reliability of the detection method, so that the purpose is to perform detection according to the national standards, the industrial standards or the detection standards of certain substances to meet the detection accuracy and the anti-interference performance.

The system configuration of the treatment method of the VOCs gas treatment technology comprises a necessary monitoring control system besides a gas generating device, a gas purifying device, a gas recovering device and a gas detecting system, wherein PLC control of temperature, humidity, particulate matters, VOCs and the like is arranged at the gas inlet end; and the necessary temperature, humidity, VOCs concentration, ozone concentration on-line monitoring and the like can also be arranged at the outlet end of the waste gas. In addition, a pressure sensor can be arranged on a passage of the whole system to monitor the pressure drop of the whole system under different governing technologies under different wind speeds, and data storage work is well done for the type selection of the equipment fan. In addition, the change rule of some parameters in the purification process can be mastered through some necessary sensors, such as an anemometer and the like, and necessary supporting conditions are provided for the technical scheme, the process kit and the purification equipment design of the actual engineering so as to improve the purification efficiency of the treatment technology and the treatment equipment.

The utility model discloses a VOCs exhaust-gas treatment system's establishment in, be applicable to VOCs engineering laboratory evaluation and administer the validity of technique and administer the purifying power of technique under the specific condition, avoid the bulk utilization of inefficient VOCs administration technique or VOCs administration technique to obtain high-efficient application. Through performance testing or characterization of the VOCs treatment system, extensive use of inefficient technologies is greatly reduced or the inefficient technologies are gradually improved, which is beneficial to gradual specification development of VOCs markets.

Of course, the establishment of the system for treating waste gas containing VOCs can not only evaluate the purification capability of a single VOCs gas or a composite VOCs gas by treatment technology, but also treat the purification capability of other gases by using the purification equipment or not limited to the above-mentioned purification equipment, or treat new materials used in some purification equipment. The establishment of the waste gas treatment system can be actually connected with engineering tests, is closer to the actual working condition, and is more beneficial to the design of engineering schemes and the design and processing of purifying equipment.

Example 1

The method adopts a photolysis photocatalysis treatment technology to purify simulated gas, and comprises the following specific operation steps:

1) assembling a testing device: the testing device mainly comprises a gas generating device, a gas mixing device, a photolysis photocatalysis device, a gas recovery device and a gas detection device.

2) After the purification device is assembled, starting the equipment, collecting gas after the equipment is started for 30min, then testing and analyzing, and calculating the purification efficiency.

Example 2

1) assembling a testing device: the testing device mainly comprises a gas generating device, a gas mixing device, a photolysis photocatalysis device, a gas recovery device and a gas detection device. The difference from example 1 is that: an ozone decomposition device is arranged after photolysis photocatalysis.

Example 3

The method adopts a photolysis photocatalysis treatment technology to treat simulated waste gas, and comprises the following specific operation steps:

Example 4

1) assembling a testing device: the testing device mainly comprises a gas generating device, a gas mixing device, a photolysis photocatalysis device, a gas recovery device and a gas detection device, and the whole process flow is shown in figure 2.

Example 5

TABLE 1 purification efficiency of five experiments

Serial number	Purification efficiency/%)
		1	75.5
2	80.3
		3	95.4
4	79.4
		5	85.8

Conventional technical knowledge in the field can be adopted in the content which is not described in detail in the present invention.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art will understand that modifications and equivalent substitutions can be made to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention, and all of them shall fall within the scope of the claims of the present invention.

Claims

1. A VOCs waste gas treatment system comprises a gas generation device, a gas purification device, a gas detection device and a gas recovery device, and is characterized in that the gas generation device, the gas purification device and the gas recovery device are sequentially connected along the direction of an air duct; the gas detection device is respectively connected with a gas inlet and a gas outlet of the gas purification device; the gas recovery device adopts a fluidized bed type active carbon adsorption device or a fixed type active carbon adsorption device.

2. A VOCs waste gas treatment system as claimed in claim 1, further comprising a gas mixing device, wherein the gas inlet of the gas mixing device is connected to the gas outlet of the gas generating device, and the gas outlet of the gas mixing device is connected to the gas inlet of the gas purifying device.

3. A VOCs exhaust treatment system as claimed in claim 1, further comprising a monitoring and control device, wherein the monitoring and control device is provided at an inlet end of the gas purification device and an outlet end of the exhaust gas, respectively.

4. A VOCs exhaust treatment system as claimed in claim 1, wherein the exhaust treatment device further comprises a blower connected to the gas outlet of the gas recovery device.

5. A VOCs waste gas treatment system according to claim 1, wherein the gas purification unit comprises a single purification unit and/or a multiple purification unit,