Descaling/Chemical cleaning is more effective as the removal of inorganic and organic foulants from process lines, equipments, surface etc. Cleaning should be combination of three elements i.e. Solvents (acid, alkali, surfactant), Fluid velocity (stirring, spraying, agitation, air rumbling and steam addition etc) Heat (hot water or hot surface). Cleaning is divided into two categories : pre operational cleaning and routine maintenance cleaning.