The decanter centrifuge is suitable for solid-phase dewatering, liquid-phase clarification and separation, liquid-liquid-solid three phase separation and size-grading of various suspensions with solid-phase particle sizes of 0.005-15mm, consistency of 1-40% and temperature of ≤ 100°C, esp. for separatong the suspensions whose consistency and particle size vary greatly and for which recovery of filter cloth is difficult, such as treatment of PVC resins, ammonium sulfite, barrium carbonate, strontium sulphate, lithopone,starch, diatomite, plaster, bauxite, soybean protein, peanut protein, fruit juice, drinks, vegetable oil, citric acid, powder of blood, powder of titanium white, kaolin clay and drilling mud, etc., and dewatering of washed coal and fine coal, purification of waste oil, treatment of grain stillage liquid waste and municipal sewage and mineral classification. Besides, it is suitable for waste water treatment of electric power plant sludge, printing and dyeing sludge, paper manufacture sludge.