VOC Content in Industrial Coatings

[STRCIVIL]

I am currently studying the coating spec. for wastewater treatment plant. Rule 1113 set out by the AQMD in California, reduces the VOC content in coatings. VOC content limit is getting lower and lower. I am not a chemical engineer, so I might be asking some dumb questions here. I just wanted to know. Here are my questions:

1) What is the purpose of VOC in coatings? Is it just basic component required in every coating product?

2) How does it relate to solids in coatings? solids are voc's? or are they two separate things?

3) what are the effects of lowering VOC in coatings? Any performance decrease or installation difficulties? or any other effects?

Thank you in advance.

 

[aspearin1]

VOC = volatile organic carbons. Basically carbon containing solvents that evaporate. Common in coatings: Toluene, Xylene, Methylethyleetone (MEK), Acetone.... These solvents are great, help give a nice uniform dispersion of solids, go on smooth, cure quickly... but also cause have been known to cause cancer in the state of California. If they get in the water, then they become a real costly and near impossible remediation problem.

People are lazy but are also innovators. Because of the stricter policies engineers have been forces to reformulate coatings with a lower VOC content. Lots of industrial coatings have more recently become water borne, because of environmental, health and safety issues. But this would not have happened had states like CA not been strict with the policy.

ChemE, M.E. EIT
"The only constant in life is change." -Bruce Lee

 

[bimr]

The paint manufacturers have been transitioning from oil based paints to water based paints because of changes in air pollution regulations. Obviously, the oil based paints contain much higher VOC's because they contain organic solvents that evaporate.

The prevalent VOC control technique involves reducing the total amount of VOC likely to be evaporated and emitted. This is accomplished by use of low VOC content coatings and by improvements in transfer efficiency. New coatings with relatively low VOC levels can be used instead of the traditional high VOC content coatings. Examples of these new systems include waterborne coatings, powder coatings, and higher solids coatings. Improvements in coating transfer efficiency decrease the amount that must be used to achieve a given film thickness, thereby reducing emissions of VOC to the ambient air. By using a system with increased transfer efficiency (such as electrostatic spraying) and lower VOC content coatings, VOC emission reductions can approach those achieved with control devices

You should contact a paint manufacturer such as Tnemec for recommendations on the coatings that will meet your needs and meet the air pollution regulations.