Castle Cement’s Ketton Works replaced coal for firing of its rotary kilns, with Profuel, an alternative fuel comprised of cardboard, paper, plastics, textiles and carpet and other green fuel waste materials.

In 2002 the company built a UK£4m (US$7.56m), three-stage Profuel preparation plant that required conveying and weighing of the Profuel material as well as pulverised fuel ash (PFA) that is heated along with calcium oxide, silica, aluminium and iron in horizontal rotary kilns at 1600°C (2940° F).

The company chooses to convey and weigh the Profuel materials differently than it did the PFA.