The first area to look at is batch time. In modern plants, typical batch times are 16-19 hours for alkyds, 14-16 hours for saturated polyesters (with phthalic anhydride feed) and 18-25 hours for saturated polyesters (with isophthalic acid feed), respectively. Of course, batch times vary somewhat from one plant to another, due to different formulations and types of operations. Generally speaking, batch times are 20% to 50% longer in older plants. This leaves a lot of room for management to spend a few dollars and justify a return on investment.
Shorter batch times mean higher production rates using the same equipment. Consequently, one must look for the obvious bottlenecks in the process, such as those noted below.