Tanks can generally be divided into two main categories according to function: storage- or process tanks. The capacity of storage tanks, mostly executed with insulated walls, varies between 100 till 150,000 litres. The tanks are fitted with various types of agitators. (propeller- or paddle agitators) In the process tanks, the product is heated or cooled. They have stainless steel shells, with or without insulation. The storage capacity of these tanks varies between 100 till 20,000 litres. These tanks are implemented with disc- or scraper agitators.