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Volatile organic compounds (VOCs), as one of the major precursors of air pollution, pose a serious threat to the environment and human health. Industries such as petrochemicals, chemicals, industrial coating, and packaging printing are major sources of VOC emissions. The VOCs emitted by these industries not only lead to the formation of secondary pollutants in the atmosphere, such as ozone and fine particulate matter (PM2.5), thereby exacerbating air pollution, but they can also cause damage to the human respiratory system and nervous system. Therefore, strengthening the control of VOCs in these industries is of great significance for improving air quality and protecting public health. Today, we will explore the technical approaches for controlling VOCs in industries such as petrochemicals, chemicals, industrial coating, and packaging printing. By analyzing actual cases, we will examine the suitability and effectiveness of different control methods, with the aim of providing guidance for relevant enterprises and facilitating the further advancement of VOCs control efforts. I. Technical approaches and cases for VOCs control in the petrochemical industry 1. Technical approaches (1) Source control: Optimize the process flow and use raw materials and products with low VOC content. For example, use clean pyrolysis feedstocks to reduce the generation of VOCs during the pyrolysis process. Strengthen equipment management, improve the sealing performance of equipment, and reduce material leakage. If advanced sealing technologies and equipment are used, the devices should be inspected and maintained regularly. (2) Process management: Implement Leak Detection and Repair (LDAR) techniques, conduct regular inspections of equipment components, and promptly identify and repair leakage points. Closed-process production methods and equipment, such as closed conveying pipelines and reaction vessels, are used to reduce the uncontrolled emissions of VOCs. (3) End-of-pipe treatment: Adsorption technology: VOCs are adsorbed using adsorbents such as activated carbon and zeolites, and then desorbed and regenerated once saturation is reached. Suitable for the treatment of VOCs exhaust gas with low concentrations and high flow rates. Catalytic combustion technology: With the help of a catalyst, VOCs undergo oxidation at lower temperatures, resulting in the formation of carbon dioxide and water. Suitable for the treatment of VOCs exhaust gases at medium to high concentrations. Regenerative Thermal Oxidation (RTO) technology: VOCs exhaust gases are heated to over 760°C to cause their oxidative decomposition, while a regenerator is used to recover heat and reduce energy consumption. Suitable for the treatment of VOCs exhaust gases with high concentrations and large flow rates. 2. Case Company Overview: This company primarily produces petrochemical products such as ethylene and propylene, and generates large amounts of VOCs waste gases during the production process. Governance measures: The enterprise has adopted a comprehensive governance approach that combines \"source control + process management + end-stage treatment\". In terms of source control, the pyrolysis feedstock was optimized to reduce VOC emissions ； In process management, LDAR technology was implemented to inspect and repair over 2,000 equipment components ； In terms of end-of-pipe treatment, multiple RTO units have been installed to handle high-concentration VOCs exhaust gases. Governance effectiveness: As a result of these measures, the enterprise’s VOCs emission levels have been significantly reduced, meeting both the national and local emission standards; at the same time, environmental pollution and resource waste have been decreased. II. Technical Approaches and Cases for VOCs Control in the Chemical Industry 1. Technical Approaches (1) Substitution at the source: Promote the use of coatings and adhesives with low VOC content, such as water-based coatings and powder coatings, to replace traditional solvent-based coatings and adhesives. Advanced production processes and equipment are employed to reduce the use of organic solvents. (2) Process control: Improve ventilation in the production workshops, install local exhaust systems, and promptly collect and treat the VOCs waste gases generated. Strict management is applied to aspects such as material storage, transportation, and use during the production process, in order to reduce VOC emissions and volatilization. (3) End-of-pipe treatment: Adsorption concentration-catalytic combustion technology: First, adsorbents are used to adsorb and concentrate low-concentration VOCs exhaust gases, and then the concentrated exhaust gases are sent to a catalytic combustion unit for treatment. Biological treatment technology: Utilizes the metabolic activities of microorganisms to break down VOCs into harmless substances. Suitable for the treatment of low-concentration, biodegradable VOC waste gases. 2. Case Company Overview: This company primarily produces chemical products such as pesticides and dyes, and during its production process it generates VOCs emissions containing harmful substances such as benzene, toluene, and xylene. Governance measures: The company first carried out substitution at the source, replacing some solvent-based coatings with water-based coatings ； In terms of process control, ventilation in the production workshops has been improved, and multiple local exhaust systems have been installed ； For end-of-pipe treatment, the adsorption concentration-catalytic combustion technology is employed to treat VOCs exhaust gas. Governance results: Following the implementation of governance measures, the concentration of VOCs emitted by the enterprise has significantly decreased. The air quality in the workshops has improved, and the health of employees has been better protected. III. Technical Approaches and Cases for VOCs Control in the Industrial Coating Industry 1. Technical Approaches (1) Source control: Promote the use of coatings with low VOC content, such as high-solid-content coatings and water-based coatings, to reduce the amount of organic solvents used in coatings. Optimize the coating process by using efficient coating techniques such as electrostatic spraying and air-assisted airless spraying to improve the utilization rate of coatings. (2) Process management: Strengthen environmental management in the painting workshop by establishing enclosed painting areas to reduce uncontrolled emissions of VOCs. Regularly maintain and service the coating equipment to ensure its proper operation and to reduce paint leakage and splashing. (3) End-of-pipe treatment: Activated carbon adsorption technology: This method uses activated carbon to absorb VOCs, and is suitable for the treatment of VOCs exhaust gas with low concentrations and intermittent emissions. Low-temperature plasma technology: Low-temperature plasma is generated through high-voltage discharge, causing VOC molecules to undergo decomposition and oxidation reactions. Suitable for the treatment of VOCs exhaust gas with low concentrations and low flow rates. 2. Case Company Overview: This company is mainly engaged in automobile manufacturing and painting, and a large amount of VOCs emissions are generated during the painting process. Governance measures: The enterprise has adopted a comprehensive governance approach that combines \"source control + process management + end-stage treatment\". In terms of source control, the use of high-solid-content coatings and water-based coatings has been promoted ； In terms of process management, environmental control in the painting workshop has been strengthened, with enclosed areas designated for painting operations ； For end-of-pipe treatment, a combination of activated carbon adsorption technology and low-temperature plasma technology is employed to treat VOCs exhaust gases. Governance effectiveness: As a result of these measures, the company’s VOC emissions have been reduced to levels that meet both national and local emission standards, while the quality of coating applications and production efficiency have also improved. IV. Technical Approaches and Cases for VOCs Control in the Packaging and Printing Industry 1. Technical Approaches (1) Substitution at the source: Promote the use of inks with low VOC content, such as water-based inks and soy inks, to replace traditional solvent-based inks. Environmentally friendly printing processes such as flexography and offset printing are employed to reduce ink consumption and VOC emissions. (2) Process control: Improve ventilation in the printing workshop, install local exhaust systems, and promptly collect and treat the VOCs emissions generated. Regularly clean and maintain the ink rollers, printing plates, and other components of printing equipment to reduce ink residue and evaporation. (3) End-of-pipe treatment: Regenerative catalytic oxidation technology (RCO): Under the action of a catalyst, VOCs exhaust gases are heated to a lower temperature, causing them to undergo an oxidation reaction that produces carbon dioxide and water. Suitable for the treatment of VOCs exhaust gases at medium to low concentrations. Photocatalytic oxidation technology: Ultraviolet light is used to irradiate the catalyst, generating highly oxidizing free radicals that break down VOCs into harmless substances. Suitable for the treatment of VOCs exhaust gas with low concentrations and low flow rates. 2. Case Study: Company Overview: This company is mainly engaged in the printing of products such as food packaging and pharmaceutical packaging; during the printing process, VOCs emissions containing harmful substances such as benzene, toluene, and xylene are generated. Governance measures: The company implemented substitution at the source, replacing some solvent-based inks with water-based inks ； In terms of process control, ventilation in the printing workshop has been improved, with multiple local exhaust systems installed ； For end-of-pipe treatment, RCO technology is employed to treat VOCs exhaust gases. Governance effectiveness: As a result of these measures, the enterprise’s VOCs emission levels have been significantly reduced, improving the working conditions in the workshops and ensuring compliance with environmental regulations. In summary, through the analysis of the technical approaches and case studies for VOCs control in industries such as petrochemicals, chemicals, industrial coating, and packaging printing, the following conclusions can be drawn: 1. Source control is key: Using raw materials and products with low VOC content, as well as optimizing production processes and equipment, are the most effective ways to reduce VOC emissions. 2. Process management cannot be ignored: Strengthening environmental management in production workshops and implementing strict controls over aspects such as the storage, transportation, and use of materials during the production process can help reduce uncontrolled emissions of VOCs. There are various end-of-pipe treatment technologies: Depending on the characteristics of different industries and the patterns of VOC emissions, appropriate end-of-pipe treatment technologies such as adsorption technology, catalytic combustion technology, and regenerative thermal oxidation technology can be selected to further reduce VOC emission levels. 3. The comprehensive treatment plan yields significant results: By adopting a comprehensive approach that combines \"source control + process management + end-stage treatment\", it is possible to more effectively reduce VOCs emission levels, meeting both national and local emission standards. In the future, as environmental regulations become stricter and technology continues to advance, the management of VOCs will face more challenges as well as opportunities. Relevant enterprises should actively adopt advanced governance technologies and equipment to strengthen environmental management, promote the thorough implementation of VOCs control measures, and make greater contributions to improving air quality and protecting public health.