A secondary process is something that supports the primary process. Generating electricity is the primary process of a power plant.
A secondary process would be keeping the boiler supplied with steam. The primary process of an ice cream dispenser at Dairy Queen is to squeeze out ice cream.
A secondary process would be keeping the ice cream cold. Making red bricks is the primary process of a brick kiln.
Secondary processes would be firing the burners, and conveying the bricks through the kiln. If this helped, be sure to "Recommend" Kevlarster