Solvent Reporting in Towels can Improve your VOC Management

Jodi Drew ITU AbsorbTech Environmental Engineer

The new Biden administration has stated that environmental protection and climate control is a focus.

Recent years have seen increases in potential fines related to Clean Air, Clean Water, RCRA, and all EPA program violations, including non-compliance with the EPA Wipes Rule. Likewise, the fine amounts are tied to the inflation index and continue to rise each year.

Many fines are based on air and water emissions that could impact atmospheric elements that impact climate control. These emissions include the volatile organic compounds (VOCs) found in solvents and inks used in everyday graphics operations.

To ensure you do not exceed the allowable limits set by EPA and found in your permits, VOCs used should be inventoried and accounted for at every downstream process. Emissions to the air, water, and waste streams are sources for potential exceedances, violations, and fines.

The Importance of Solvent Tracking

Tracking where the solvents in your facility are actually going isn’t always an easy process. Printers often must rely on assumptions or estimates. For example, according to the EPA reporting measure in Pennsylvania, 50% is the allowed estimate for how much solvent goes into the towels or wipes used to clean printing presses and wipe down screens and beds. But in my experience, there can be a huge variance with printers ranging anywhere from 20% to 70% of solvent actually going into the towels. The variance is dependent on how the solvent is applied and managed by end-users.

The key to solvent management and accountability is to more accurately identify where the inks and solvents are going.

What is a Towel Solvent Report

A towel solvent report is a proprietary report generated by ITU AbsorbTech that lists how many solvents were recovered from your printer towels.  The report is generated monthly and shows the solvent recovery in ML.

How do I use my Towel Solvent Report?

While the EPA allows you to estimate how much solvent goes into towels, the towel report depicts the actual amount of solvent that went into your towels.  This, in turn, helps you determine if you are over or under the allowed estimate.  Armed with this valuable information, you can more easily identify where to focus your solvent reduction strategies.

For example, if the solvent recovered from your towels is less than 50% of total usage, this could mean a portion of the process is over permit limits. Conversely, if the solvent recovered is higher than 50%, you may have room in your permit caps for growth by using the additional volume subtracted from emissions calculations. You should also look at process material handling methods to reduce the amount of solvent used.

Solvent Reduction Strategies

A good solvent plan will include methods to minimize and reuse solvent.

Careful planning and education can reap huge benefits. Here are some solvent reduction tips:

• Use job scheduling to reduce press clean-up.
• Dedicate presses to specific colors or special inks.
• Remove excess ink with a scraper before using a wipe.
• Use pumps or squeeze bottles to dampen towels.
• Use precise measuring and pour in a funnel to reduce splashing or spraying.
• Gravity drain or mechanically wring saturated shop towels to remove excess solvent for recovery.
• Reuse spent solvent for other cleanings, such as mopping. Start with the cleanest need and work your way to the dirtiest need.
• If you must pour solvent over a roller, use a drip pan.
• Use recirculating solvent sinks for parts cleaning.
• Partner with a towel cleaning service to clean and recycle the solvent from your solvent-contaminated wipes.
• Employ life cycle thinking to gain a holistic perspective of your operation’s environmental footprint

In summary, it’s important to develop and maintain good solvent management practices that will benefit your business and the environment.