Cobalt Boats had a goal to manufacture high-quality, highly functional boats for outdoor enjoyment. Therefore, it is only natural that they have a concern about the environment and are taking measures to prevent pollution. As part of this effort, Cobalt has an environmental manager at their Neodesha, KS location, who had attended the Kansas Pollution Prevention conferences and seminars. Management had some ideas they thought would help improve the efficiency of operations and reduce Cobalt’s environmental impact.
Previously, Cobalt had tried recycling acetone by hiring a contractor to do the job. This was not successful, however. The contractor was not able to control the distillation process as tightly as needed and styrene, dissolved in the acetone from the resin used to make the boats, was distilled along with the acetone. This meant that workers using the acetone had skin reactions from the styrene.
The answer to the problem was found in a solvent recovery system engineered and built by Progressive Recovery, Inc. (PRI). To demonstrate the viability of the PRI technology, a field visit was made to a plant that supplies OEM automotive finishes that had a PRI system of nearly identical design to the one proposed for the Sherwin Williams plant and had been in service for several years. The unit was designed to operate unattended and process a high variable blend of solvents, producing 5000+ gallons of clean solvent per day.
During the ongoing discussion of the plant’s needs and wants, it was determined that the facility did not want one large distillation unit but two smaller ones with the total capacity to meet their needs. Having two systems gave them redundancy and prevented major problems if one unit was down for maintenance. This and other details relating to the equipment and operation were agreed upon and authorization was given to start the project.
When Cobalt wanted to reinstate the acetone recycling program, it had to overcome the negative perception from the previous attempt. Cobalt’s environmental manager thoroughly researched recycling equipment on the market and found a very good unit that controls the distillation temperature so accurately that only acetone and not styrene is recycled. Now the workers cannot tell the difference between virgin and recycled acetone.
In addition to the recycling acetone, Cobalt gets a final use from its used acetone before it goes into the still. Some clamps get caked with resin and are very difficult to clean. These are placed in a basket in a drum. All of the used acetone gets its final use by being poured over these clamps. By gravity separation, the solids go to the bottom of the drum, and the liquids are taken off and put into the acetone distillation units.
Cobalt was able to pay for its distillation unit in less than eight months. This payback was calculated on the basis of reduced acetone purchased and savings on acetone waste disposal. The distillation unit can cover 10 gallons per hour. Cobalt currently uses about 2,000 gallons of acetone per month. The recovery rate for the still is about 80 percent.
Cobalt is an example of how a successful project can open the door to more waste-saving projects.