How to deal with the wastewater produced by water-based ink in the printing process

How to deal with the wastewater produced by water-based ink in the printing process

How to deal with the wastewater produced by water-based ink in the printing process
Lead edge feeder colors Flexo printer slotter rotary die cutter machine  Now the scope of application is more and more, especially some articles in contact with human skin, such as books, magazines, corrugated paper and other prints, in the packaging and printing of wine, tobacco, medicine, cosmetics, children's toys, as well as milk and drinks such food grade packaging brush is also widely used. Waterborne ink in production and printing, due to equipment cleaning and other reasons, it is also inevitable to produce some wastewater. These wastewater due to contain a small amount of chemical additives, if directly discharged, will pollute the environment, how to make the use of water-based ink more environmentally friendly, you need to do some treatment of these wastewater.



How to treat, let's first look at the characteristics of water-based ink wastewater?

Although water-based ink itself and printed products are safe and environmentally friendly, many additives are needed to assist printing in the process of printing, such as organic pigments, azo pigments, phthalocyanine pigments, nitro pigments, lake pigments, reducible pigments, nitroso pigments, heterocyclic pigments and other types. In addition, it also contains stabilizers, defoaming agents, blockers, surfactants, preservatives and more than ten kinds of additives. The wastewater produced by water-based ink is weak alkaline, contains some organic matter, high chroma, low RATIO of BOD/COD, need to be treated to reach the comprehensive sewage discharge standard (GB8978-1996)



Here is the specific implementation method:

1. Adjust the pH, the workshop ink wastewater concentrated in the underground collecting tank, after a lift to the acid extraction tank, add sulfuric acid in the acid extraction tank, adjust the pH value to 2.0~3.0,

2. The filter: The dissolved acrylic resin in the wastewater into solid, precipitation from the wastewater, through the sand filter drying tank filtration, filtering liquid, and the solid material removal, precipitation of propylene acid, water filtration CODcr can be reduced to about 1500mg/ L, after acidification slag removal of wastewater into the middle pool, due to the pH value of the wastewater has been reduced to 2.0~3.0, The subsequent treatment is more clear. This hydrolytic acidification process is mainly used for wastewater with high concentration of organic matter and solid suspended matter, which is an important step in the whole process.

3. Degradation: If the solid suspended solids in the water are high, hydrolytic bacteria will capture them through the extracellular mucosa and hydrolyze them into molecular fragments with extracellular enzymes, and then enter the cell for metabolism. Incomplete metabolism will degrade the solid suspended solids into soluble organic matter, and the water will become clear. Hydrolytic bacteria hydrolyze organic matter, break the covalent bond of organic matter, release the bond energy, so as to use this bond energy to complete life activities.

4: neutralization precipitation: waste water again after ascending to counteract settling basin, adjusting the pH to 8.0 ~ 9.0, while adding PAC (polyaluminium chloride) and PAM (polyacrylamide), under the action of PAC and PAM, waste water coagulation reaction, forming a large number of alum trivia, after precipitation separation alum flowers, supernatant fluid into the aerobic pond, biochemical treatment. The treated waste water is settled by a secondary sedimentation tank.



Such a set of processes go down, the basic production process can produce wastewater, discharge standards. Leave a clean sky for future generations. Star color technology Co., Ltd. has been committed to improving environmental protection, the production of water-based ink to reach the international advanced water products.

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