How to improve the exhaust gas collection rate of VOCs?

Jiangsu Zhongming Environmental Protection Technology Co., Ltd. is an environmental engineering company engaged in industrial waste gas on-site research, technology research and development, process customization, equipment manufacturing, project site construction and installation, operation and maintenance. At present, the company has 8 branches in the country, including four standard production plants, which are located in Suzhou, Langfang, Hebei and Shenyang, with a total production area of more than 42,000 square meters. The company has more than 10 years of experience in environmental protection equipment manufacturing, and now has a scientific quality management system and passed the ISO9001-2008-14001-18040 quality management system and the EU CE certification.

The core products are catalytic combustion equipment, photo-oxygen catalytic equipment, RTO, RCO, activated carbon adsorption equipment, condensation and low-temperature plasma equipment, and the successful implementation of waste gas treatment projects of hundreds of factories has left a good reputation in the field of VOCs waste gas treatment

Following the principle of "collecting all receivables and collecting them by quality", the waste gas collection system is scientifically designed to transform unorganized emissions into organized emissions for control.

If a fully enclosed air collection hood or confined space is adopted, unless there are special requirements of the industry, a slight negative pressure state should be maintained, and the ventilation volume should be reasonably set according to the relevant specifications.

If a local gas collection hood is used, the VOCs fugitive emission position farthest away from the opening surface of the gas collection hood shall be controlled at a speed not lower than that, and the relevant provisions shall be implemented if there are industry requirements.

VOC exhaust gas treatment usually requires the use of some equipment dedicated to dry front doors, the following are the common ones:

Combustion furnace: The burner is the core equipment for the incineration method to treat VOC exhaust gas, which can directly burn the VOC in the exhaust gas into CO2 and H2O, and produce high-temperature flue gas. The combustion furnace usually needs to be equipped with equipment such as an oxygen system, a combustion control system, and an exhaust system.

Adsorption tower: The adsorption tower is the core equipment for the treatment of VOC waste gas by adsorption, which usually uses adsorbents such as activated carbon or molecular sieve to adsorb VOCs. The adsorption tower needs to be combined with a heating and desorption system to reuse the adsorption collapse agent.

Condenser: The condenser is the core equipment for the condensation treatment of VOC exhaust gas, which can cool the VOC in the VOC exhaust gas to low temperature to make it liquid state, and then reduce the concentration of VOC by separating and **. The condenser usually needs to be matched with cooling systems, separation systems and other equipment.

Bioreactor: The bioreactor is the core equipment for the biological treatment of VOC waste gas, which can use microorganisms to convert VOC into carbon dioxide and water. Bioreactors usually need to be equipped with equipment such as oxygen supply systems, temperature control systems, and pH control systems.

Other equipment: In addition to the above-mentioned core equipment, the treatment of VOC exhaust gas also requires supporting ventilation system, exhaust gas collection system, exhaust gas analysis system, exhaust gas emission control system and other equipment.

VOCs (volatile organic compounds) is the main component of industrial waste buried sail gas, which has a greater impact on the atmospheric environment and the human body, and the composition is more complex and difficult to treat, so the attention of environmental protection related departments and enterprises to VOCs waste gas treatment is increasing. In order to improve the effect of VOCs waste gas treatment, it is necessary to identify the source of waste gas, fully understand the hazards of waste gas, and then carry out targeted treatment work to ensure that VOCs waste gas treatment is carried out efficiently. In order to create a good air environment, we all need to understand VOCs exhaust gas treatment technology.

What kind of technology is it?

1.Regenerative incineration technology.

Regenerative liquid bi incinerator (RTO) is the most mature, stable and effective organic waste gas treatment equipment, which can treat volatile organic gases (VOCs) and odors emitted in industrial production processes. The RTO system uses high-temperature oxidation to remove the exhaust gas, converts the exhaust gas into carbon dioxide and water vapor by controlling the temperature, residence time, turbulence coefficient and oxygen amount, and improves the heat released when the exhaust gas is decomposed, so as to achieve the dual purpose of environmental protection and energy saving.

Features: The operating cost is very low when dealing with large flow and low concentration organic waste gas; The system is self-adaptive, stable and safe; The equipment is assembled in the factory, and the system installation time is short; It can treat a variety of components, almost all organic waste gases, organic waste gases containing S, N and halogen elements; It is suitable for chemical, petrochemical, pharmaceutical, painting, printing and other processes using organic solvents.

VOCs (volatile organic compounds) exhaust gases can be collected in several ways:

Adsorption collection method: the adsorbent is used to adsorb the VOCs in the exhaust gas, and then the VOCs are desorbed from the differential adsorbent by pyrolysis or condensation. Commonly used adsorbents include activated carbon, molecular sieves, etc.

Condensation collection method: The VOCs are condensed into a liquid state at low temperature, and then the mu group is separated and treated. This method is suitable for situations where the concentration of VOCs is relatively high.

Activated carbon adsorption-desorption method: the exhaust gas is passed through the activated carbon bed, and the VOCs are adsorbed on the surface of the activated carbon, and then the VOCs are desorbed from the activated carbon by thermal desorption.

Biological treatment method: the use of microorganisms to biodegrade VOCs. This method is suitable for low VOCs concentrations in the exhaust gas.

The above collection methods have their own advantages and disadvantages, and the appropriate collection method should be selected according to the industry of exhaust gas generation, process characteristics, VOCs composition and concentration, and other factors.

Exhaust gas catalytic combustion equipment is a kind of machinery and equipment used to treat exhaust gas, and it is also called RCO catalytic combustion device. The key of the machine and equipment is composed of five processes: heat exchanger, engine combustion chamber, catalytic reaction speed, residual reed chain heat system software, and flue gas emission. According to the process of igniting the industrial waste gas at a lower ambient temperature of the metal catalyst as the substance, it is also called flameless ignition.

VOCs (volatile organic compounds) are a common class of exhaust pollutants that may have adverse effects on human health and the environment. In order to reduce the emission concentration of VOCs, pretreatment is generally required, and the following measures can usually be taken:

Adsorbent adsorption: By adding specific adsorbents to the exhaust gas, such as activated carbon, molecular sieve, etc., volatile organic compounds can be effectively adsorbed and removed from the exhaust gas.

Activated oxidation: The use of UV light or ozone and other methods to introduce reactive oxidants into the exhaust gas to decompose volatile organic compounds into harmless substances.

Thermal oxidation: Through high-temperature oxidation, VOCs are decomposed into harmless substances such as water vapor and carbon dioxide at high temperatures, and the emission concentration of exhaust gas can be effectively reduced.

Condensation**: Cooling the exhaust gas to a low enough temperature to condense the volatile organic compounds in it into a liquid state**, this method is suitable for situations where the concentration of a large number of organic compounds in the exhaust gas is high.

Biological treatment: By using microorganisms to degrade VOCs in the exhaust gas, such as bioreactors, biological filters, etc., high concentrations of VOCs in the exhaust gas can be removed.

It should be noted that different pretreatment methods are suitable for different types and concentrations of VOCs exhaust gases, and the specific selection of which dust method needs to consider factors such as cost and technical feasibility. In general, the combination of multiple pretreatment methods will be more effective in reducing the emission concentration of VOCs, and at the same time, it can also improve the stability and operational efficiency of the exhaust gas treatment system.

VOCs waste gas treatment system is a system used to treat volatile organic compounds waste gas, which is generally composed of purification equipment, pipelines, fans, etc. In order to ensure the normal operation of the system and effectively treat the exhaust gas, regular maintenance and maintenance are required.

The following are the maintenance precautions for VOCs exhaust gas treatment system:

1.Replace the filter and adsorbent regularly: The filter and adsorbent in the exhaust gas purification equipment need to be replaced regularly to ensure its purification efficiency and ventilation.

2.Regular cleaning of the outer surface of the pipeline and equipment: After a long period of use, there will be adsorption dirt on the inner wall of the pipeline and the surface of the equipment, which will affect the effect of waste gas treatment, so it is necessary to clean it regularly.

3.Regular inspection of fans, exhaust pipes, and barometers: Equipment such as fans, exhaust pipes, and barometers need to be checked regularly to ensure proper operation.

4.Regular maintenance of electrical components: Electrical components such as sensors and inverters in exhaust gas purification equipment need regular maintenance to ensure their sensitivity and normal operation.

5.Lubricate regularly: Lubricate the equipment regularly to reduce friction and motion noise.

The above are some precautions for maintaining the VOCs exhaust gas treatment system, I hope it will help you.

Filtration + activated carbon adsorption equipment.

Waste gas treatment equipment should be turned on before the production equipment, and then shut down before the production equipment.

Spray + activated carbon adsorption spray washing.

Waste gas treatment equipment should be turned on before the production equipment, and then shut down before the production equipment.

Activated carbon adsorption + combustion (CO).

This process has high efficiency in treating waste gas, and is suitable for industrial coating enterprises with a large amount of VOCs raw and auxiliary materials.

Waste gas treatment equipment shall be opened before the production equipment, and then shut down the production equipment.

When the combustion method is used to treat the waste gas, it should generally be adsorbed (concentrated) by activated carbon before combustion.

Activated carbon should be checked regularly and replaced in time if it has failed.

Regenerative combustion. Waste gas treatment equipment should be turned on before the production equipment, and then shut down before the production equipment.

Strictly abide by the operating procedures and strictly prevent safety accidents;

When the halogen-containing waste gas is incinerated, it is easy to cause secondary pollution.

Spray towers. Regularly dredge the pipes, clean the surface dirt, and ensure the smooth flow of water;

Regularly salvage paint residue to prevent blockage of facilities;

Replace or replenish the water for the spray tower regularly.

Excessive air volume can easily lead to damage to the filter device and reduce the service life of the facility;

It is easy to be clogged by paint residue and should be replaced in time (1-2 weeks);

After blocking, the air cannot be exhausted normally, the filtration efficiency is reduced, and electricity is consumed.

1. Active adsorption method:In the organic waste gas treatment group, adsorption is one of the methods with good treatment effect and wide use, and the adsorbents are activated carbon, diatomaceous earth, zeolite, etc., among which activated carbon adsorption is the most widely used. Through the adsorption system, not only can the VOC concentration be greatly reduced and the exhaust gas emission standard can be realized, but also the collected matter can be reused for production through air stripping desorption after adsorption.

2. Combustion treatment method:VOC is an organic volatile substance, flammable, can be treated by room temperature or catalytic oxidation combustion, and the gas is burned into the boiler or incinerator by the induced air pipeline, but the high-temperature organic gas must also go through safety demonstration. This method is relatively complete, and can basically convert VOC into CO2 and H2O.

3. Condensation collection method:The high-temperature organic gas of the reactor can be collected by condensation, first with direct condensation and then spiral condensation, the degassing effect of this method is obvious, easy to operate, low operating cost, but the effect of low boiling point gas is not good.

Precautions for VOC exhaust gas adsorption treatment.

1. The ionizer is composed of ionic tubes, which are fragile objects and need to be handled with care. The direction of gas flow corresponds to the angle of the ion tube.

2. The ionizer should not be in direct contact with gases containing flammable and explosive, and if it contains explosive gases, it is necessary to change the installation method.

3. VOC waste gas treatment process methods include spray + plasma, spray + UV photolysis, spray + photolysis plasma, microbial method, RCO combustion method, and concentration method. In practical engineering application, microbial method can be considered for places with small gas volume and low concentration. For waste gas with flammable properties, it is generally recommended to use spray pretreatment and then other virtual early treatment processes.

The above content refers to Encyclopedia-VOC

Encyclopedia - Exhaust gas treatment.

VOC (volatile organic compounds) exhaust gas treatment needs to pay attention to the following points:

Monitoring and control VOC emissions: To ensure that VOC emissions meet the standards of local regulations, you need to monitor and control them.

Select the appropriate treatment technology: Select the appropriate treatment technology according to factors such as VOC type and emissions, such as adsorption, oxidation, low-temperature plasma treatment, etc.

Ensure that the treatment system is in good working order: Maintain and maintain the treatment system regularly to ensure that it is operating stably and effectively treating VOC exhaust gases.

Post-treatment products: VOC treatment may collide to produce solid waste, liquid waste and exhaust gas. These post-treatment treatments need to be handled properly and in compliance with local environmental regulations.

Consideration and reuse: In the process of treating VOC exhaust gases, VOCs can be considered and reused, thereby reducing resource waste and environmental impact.

Imitation In some places, when analyzing the problem of air pollution, there is always too much emphasis on objective conditions and unfavorable factors. Comparing the topography, wind direction, location, etc. with other cities, it is believed that the environmental quality is not improved mainly due to external factors, and some like to talk about imported pollution, but are not good at analyzing the internal causes, and do not strengthen their own construction, which is very unfavorable to environmental pollution control.

Volatile organic compounds, or VOCs for short, refer to organic compounds with a boiling point of **260 at atmospheric pressure or a saturated vapor pressure greater than 71 pA at room temperature. There are many types of VOCs, among which the most common ones are aromatic hydrocarbons, alcohols, cools, and aldehydes used in industrial solvents. Most of the VOCs are toxic, foul-smelling, and even carcinogenic, causing great harm to the human body and the environment, and they have continuously limited VOC emissions through legislation.

There are two main types of VOCs: stationary sources and mobile sources. The main sources of mobile use are emissions from vehicles fueled by petroleum products, such as automobiles, ships and airplanes; There are many types of stationary sources, mainly for the effluents of petrochemical processes and storage equipment, as well as various occasions where organic solvents are used, such as painting, printing, metal degreasing and degreasing, adhesives, pharmaceuticals, plastics and rubber processing, etc. In addition to these large pollution sources, there are also small pollution sources that can be seen everywhere in daily life, such as paints, coatings, floor wax, etc.

At the current state of the art, the emission of these gas-phase pollutants cannot be avoided, so there is an urgent need for technologies to effectively control these gas-phase pollutants.

VOC exhaust gas treatment.

At present, there are non-destructive methods, destructive methods, and a combination of the two. The non-destructive method is the best method, which mainly includes carbon adsorption, pressure swing adsorption, absorption, condensation and membrane separation technology, which is generally through physical methods, changing temperature, pressure or using selective adsorbents and selective permeable membranes to enrich and separate VOCs; Destructive methods include direct combustion, thermal oxidation, catalytic combustion, biological oxidation, plasma method, ultraviolet photocatalytic oxidation and their integrated technologies: mainly through chemical or biochemical reactions, using heat, light, catalysts and microorganisms to convert VOCs into CO:

and non-toxic inorganic small molecule compounds such as water. Traditionally, VOC waste gas treatment often adopts adsorption or absorption removal, combustion removal and other methods, but in recent years, biological oxidation, plasma, and semiconductor photocatalyst technologies have been greatly developed.