Every now and then we will hear something like solvents are dead from someone discussing the use of traditional flammable or combustible solvents in manufacturing processes. Indeed, over the last three decades there has been a shift toward aqueous or alternative “green solvent” technologies in areas where formerly organic solvents may have been commonly used. If water-based or other green technologies can provide suitable performance for a given application, they are being incorporated in the manufacturing process – as well they should. So does green manufacturing mean that traditional solvents are dead? Far from it, and I’ll explain why.
Consumers have been conditioned to expect high resolution, crisp, photographic quality graphics and images on packaged products on store shelves. Bright, eye-catching packaging with print media that does not smudge, rub off or fade requires solvent based inks.
Likewise, solvent based paints and coatings provide long lasting color for commercial architectural and automotive finishes that stand up to sun exposure, resisting caulking and fade, and offer impact resistance to a degree not achievable with aqueous coatings.
Manufacturing process that use solvent based inks, paints, and coatings are most effectively and efficiently cleaned using similar chemistry to the carrier solvents used in the coating materials formulation. As long as the market demands the level of performance and appearance only available with solvent based chemistry, we will be dealing with solvents.
In fact, we believe we are seeing a shift back toward solvent-based inks, especially in the printing industry, because of not only the quality of the printed product, but because of the high efficiency and recyclability of traditional solvents. Many “green” plant-based solvents, while they may be better for the environment, do not distill in as efficient a manner as traditional solvents do. Plant-based solvents solidify in the distillation unit, and often require virgin solvent to be added into the pot in order to maintain a flowable solvent, which eats into the return on investment. All this, while at the same time green solvents cost twice or three times the cost of traditional solvents. Printers have approached us saying “yeah, we’re switching BACK to traditional solvents, after realizing the futility of their ‘green’ counterparts.”
We are also contacted on a regular basis by manufacturing process professionals who are considering incorporating solvents at their plants for the first time. They know they need solvents to produce their end product but they are unsure of how to navigate the various decisions needed to handle solvents in their plant. Since solvents are very much still in high demand and there are people sorting out implementation issues, we thought it might be timely to offer again a PRI White Paper entitled “Recycling Your Own Solvents”. This informative document was written a number of years ago, but the contents remain pertinent concerning the rationale and methodology needed to make a sound and safe decision on dealing with process waste solvent.
For those of you who already own a solvent recovery system and have for some years, the White Paper might be a good review on why the system was purchased and prompt you to reflect on the cash flow generator it is to your operation. Understanding what the solvent recovery system contributes to your process may be useful in justifying budgeting for preventive maintenance to keep this valuable asset running at peak efficiency.
The link below will take you to the “Recycling Your Own Solvents” paper. Please contact the PRI Solvent Management Systems Sales Department if you like for us to size and configure the proper system for your application so you can formulate your own return on investment estimate. For our existing clients who have lost track of what their distillation means to their operating cost, give us a call and we can help you with this information.