Lyondell Polymers has designed a process to reuse its solvents used in reactor washing. Solvents used to clean process reactor internal components contain polyethylene or polypropylene solids and waxes. A series of bench and field tests determined that filtering the used solvent with a plate-and-frame filter press removed the solids and waxes eliminating the need to purchase new commercial product solvent.
Creativity is exhibited in the use of an existing technology, the plate-and-frame filter press, to eliminate the need to buy new commercial solvent after each equipment wash. Using this process to enhance our solvent washing process, Lyondell Polymers has achieved enhanced productivity, equipment efficiency and product quality while reducing raw material usage.
The environmental benefits of the solvent recycling program are many. Beginning with 1989, an average of 36,000lbs. per year of used solvent was sent for disposal. Since implementation in 1993, all used solvent has been recycled, thus virtually eliminating all off-site disposal. Solvent recycling has resulted in the elimination of the need for additional waste permitting, reduction of waste disposal costs, elimination of highway transport of waste, and reduction in the purchase of new solvent.
Details of Reductions
Additional Information :
The success of this project can be measured in three ways: the elimination of the spent solvent waste stream, the reduction in disposal costs, and reduction in commercial product solvent purchases.