Technical Guidelines for VOCs Emission Control in Plastic Packaging and Printing

my country is a big manufacturing country, and the sources of VOCs pollution are small and scattered. They involve many industries and are large in volume and wide in scope.Industrial sources are the main source of man-made VOCs emissions, involving many industries, including key industries such as petrochemicals, chemicals, industrial painting, packaging and printing, oil storage, transportation and marketing, and hundreds of sub-industries.
Plastic packaging printing
The production process and VOCs emission links in the packaging and printing industry are shown in Figure 1-22.

source reduction
(1) Raw and auxiliary materials containing VOCs
●The VOCs content in the inks used by plastic packaging and printing companies from April 1, 2021 should comply with the requirements of the table below. The VOCs content of the adhesives, cleaning agents and coatings used from December 1, 2020 should comply with Table 1- 11 requirements.

●In the same process, if the raw and auxiliary materials such as inks, cleaning agents, adhesives, and coatings used meet the low VOCs content limit requirements in Table 1-12, and the emission concentration is stable and up to standard, the corresponding production process does not require the construction of terminal treatment facilities. , the requirement that the processing efficiency of terminal treatment facilities should not be less than 80% may not be implemented.In the same process, if the VOCs content of raw and auxiliary materials used is less than 10%, the corresponding production process does not require unorganized waste gas collection.

(2) Printing process
●Plastic packaging and printing companies should adopt solvent-free lamination technology and co-extrusion lamination technology instead of dry lamination technology.
●The design of plastic packaging and printing products should be optimized to minimize the coverage ratio of graphic and text parts, the number of printing colors, the thickness of the ink layer and the number of composite layers while meeting the product functions.
●For new construction, reconstruction, and expansion projects, priority should be given to printing processes with lower levels of pollutants such as flexographic printing, water-based gravure printing, and UV gravure printing.
process control
(1)Storage
●VOCs materials such as inks, thinners, adhesives, etc. should be stored in sealed containers or bags.
●Containers or packaging bags containing VOCs materials should be stored indoors or in a dedicated area equipped with canopy, sunshade and anti-seepage facilities.Containers or bags containing VOCs materials should be capped, sealed, and kept airtight when not in use.
●Hazardous wastes containing VOCs such as waste ink, waste cleaning agents, waste activated carbon, and waste cleaning cloths should be classified and placed in labeled containers or bags, covered and sealed, kept airtight, and transported and disposed of in a timely manner. Reduce storage time in the workshop or hazardous waste warehouse.
(2) Deployment
●The preparation process of VOCs materials such as inks and adhesives should use closed equipment or operate in a closed space, and the waste gas should be discharged to the VOCs waste gas collection and treatment system; if it cannot be sealed, local gas collection measures should be taken, and the waste gas should be discharged to the VOCs waste gas collection and treatment system system.
(3) Conveying
●Liquid VOCs materials should be transported in closed pipelines.When using non-pipeline transportation methods to transfer liquid VOCs materials, closed containers should be used.
●When adding ink or diluent to the ink tank, you should use connecting tools such as funnels or hoses to reduce the escape of VOCs during the ink supply process.
(4) Printing
●The printing process should be operated in a closed space, and the waste gas should be discharged to the VOCs waste gas collection and treatment system; if it cannot be sealed, local gas collection measures should be taken, and the waste gas should be discharged to the VOCs waste gas collection and treatment system.
●Gravure and letterpress printing processes that use solvent-based inks should use a printing press equipped with a closed scraper, or take measures such as installing an ink tank cover or changing the shape of the ink tank opening to reduce the open liquid surface area of ​​the ink supply system.
●The air supply or suction outlet should avoid facing the ink tray to prevent accelerated evaporation of solvent.
(5) Composite/laminated/coated/glazed
●The laminating, laminating, coating and glazing processes should be operated in closed equipment or confined spaces, and the waste gas should be discharged to the VOCs waste gas collection and treatment system; if it cannot be sealed, local gas collection measures should be taken, and the waste gas should be discharged to the VOCs waste gas collection system processing system.
●In the laminating or laminating process using solvent-based adhesives, measures such as installing glue tank covers or partially enclosing the laminating/laminating machine should be taken to reduce the emission of VOCs.
(6) Drying
●The airtightness of the oven should be improved to reduce the unorganized emission of VOCs caused by air leakage in the oven
●The air supply and exhaust volume of the oven should be controlled to maintain a slight negative pressure inside the oven.
(7) Cleaning
●Centralized cleaning should be performed in closed equipment or a confined space, and the waste gas should be discharged to the VOCs waste gas collection and treatment system; if it cannot be sealed, local gas collection measures should be taken, and the waste gas should be discharged to the VOCs waste gas collection and treatment system.
●The amount of ink cleaning agent used should be reasonably controlled according to production needs and work procedures.
End-of-pipe management
(1) Gravure printing
●After the solvent-based gravure printing unorganized waste gas is collected, it should be treated by the treatment process of 'adsorption + condensation', 'adsorption + combustion' or 'combustion'.At present, the more mature treatment technology routes are 'activated carbon adsorption + hot nitrogen regeneration + condensation recovery', 'activated carbon adsorption/rotary molecular sieve adsorption concentration + RTO/CO', or combined with drying organized waste gas and passed through 'Burning' process.
●Solvent-based gravure printing drying exhaust gas should be treated using the treatment process of 'adsorption + condensation' or 'combustion'.At present, the more mature technical routes are 'activated carbon adsorption + hot nitrogen regeneration + condensation recovery' and 'wind reduction and concentration + RTO/CO'.
●Water-based gravure printing and drying waste gas should be treated by 'adsorption + combustion' or other equivalent methods.
(2) Flexographic printing
●Solvent-based flexographic printing and drying waste gas should be treated using the 'adsorption + combustion' treatment process.At present, the more mature technical routes are 'rotating molecular sieve adsorption and concentration + RTO' and 'activated carbon adsorption/rotating molecular sieve adsorption and concentration + CO'.
(3) Compound
●After the dry composite unorganized waste gas is collected, it should be treated by the treatment process of 'adsorption + condensation', 'adsorption + combustion' or 'combustion'.At present, the more mature technical routes are 'activated carbon adsorption + hot nitrogen regeneration + condensation recovery', 'activated carbon adsorption/rotary molecular sieve adsorption concentration + RTO/CO', or combined with drying organized waste gas and then passed through Combustion'process treatment.
●Dry composite drying waste gas should be treated using the treatment process of 'adsorption + condensation' or 'combustion'.At present, the more mature technical routes are 'activated carbon adsorption + hot nitrogen regeneration + condensation recovery' and 'air reduction and concentration + RTO/CO'.
(4) Coating
●After the coating unorganized waste gas is collected, it should be treated using the treatment process of 'adsorption + combustion' or 'combustion'.The more mature technical route at present is 'activated carbon adsorption/rotating molecular sieve adsorption and concentration + RTO/CO', or combined with drying organized waste gas and then processed through the 'combustion' process.
●The coating and drying exhaust gas should be treated through the 'combustion' treatment process.The typical treatment technology route is 'wind reduction and concentration increase + RTO/TO'.
(5) Laminating/glazing
●Solvent-based coating, solvent-based glazing and drying waste gas should be treated by 'adsorption + combustion' or other equivalent methods.
(6) Others
●The unorganized waste gas generated from blending, cleaning and other processes should be treated by 'adsorption + combustion' or other equivalent methods after collection, or combined with waste gas from printing, laminating, coating, etc.
●Intermittent and small air volume waste gas can be treated by treatment processes such as activated carbon adsorption, and the activated carbon should be regenerated or replaced regularly according to the VOCs processing volume, activated carbon processing capacity, etc.
(7) Abnormal working conditions
●When VOCs control facilities malfunction, or when the waste gas generated due to abnormal working conditions exceeds the processing capacity of the control facilities, the corresponding production equipment or process operations should be stopped immediately, and measures should be taken to seal open ink tanks, glue tanks, etc. , wait until the treatment facilities or production facilities return to normal before starting production.
●Make records related to abnormal working conditions.
Emission limits
●The VOCs exhaust gas emitted from the exhaust pipe of the workshop or production facility, as well as the VOCs unorganized exhaust gas at the factory boundary and factory area should comply with the 'Comprehensive Emission Standard of Air Pollutants' (GB 16297-1996) and 'Unorganized Emission Control Standard of Volatile Organic Compounds' ( GB 37822-2019) limit requirements; if there are stricter local standards, the local standards shall be implemented.
Monitoring Monitoring
●Strictly implement the self-monitoring and management requirements stipulated in the 'Technical Specifications for Application and Issuance of Pollution Emission Licenses for the Printing Industry' (HJ 1066-2019).
●If included in the list of key sewage discharge units, automatic monitoring facilities shall be installed at the main sewage discharge outlets specified in the sewage discharge license.
Ledger management
(1) Production facility operation management information
●Product output information: main product output (statistics are calculated separately for different process types).Records are made according to orders or shifts, and each order or shift is recorded once.
●Information on raw and auxiliary materials: the name, VOCs content, purchase amount, usage amount, inventory amount, solvent recycling method and Recycling volume, etc. (calculated separately for different process types).Recorded by purchase or recycling batch, once per batch.
(2) Operation and management information of pollution control facilities
●Organized exhaust gas treatment facilities: Records are made according to the production shift system, and records are recorded once per shift.For details, please refer to '3. Ledger Records of Governance Facilities' in Part 3.
●Unorganized exhaust gas emission control: unorganized emission sources and control measures operation, maintenance, management and other information, the recording frequency is in principle no less than once/day.
●Abnormal working conditions: Facility name and number, start and end time, pollutant emission concentration, abnormal reasons, countermeasures, whether to report, etc. The recording frequency is once/abnormal situation period.

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