TW200503968A - Method for solidifying sludge containing heavy metals and treatment agent used by the method - Google Patents

Abstract

The present invention relates to a method for solidifying sludge containing heavy metals capable of reducing the amount of cement used and thus reducing the treatment cost thereof while effectively solidifying the sewage containing heavy metals and a treatment agent used by the method. The invented method comprises pulverizing sludge containing heavy metals (e.g. Cu, Zn, Ni, etc.); feeding the pulverized sludge in a blending device; adding inorganic heavy metal stabilizer, cement, water, and organic solidifying reinforcement agent in the blending device; and performing a blending process to form a harmless solid, the treatment agent contains cement, sodium silicate, sodium carbonate, potassium carbonate, calcium chloride, ammonium chloride, magnesium chloride, sodium fluoride, aluminum chloride, brown sugar, and water, in which the ratio of the amount of cement and the amount of sludge used is 0.1-0.7, the ratio of the amount of brown sugar used and the total amount of sludge and cement is 0.004-0.008, and the ratio of the amount of chemical agent used and the total amount of cement and sludge is 2%-8%. The addition of brown sugar can reinforce the solidification function of the sludge and reduce the amount of cement used, while meeting the requirements on the compressive strength as stipulated by the Environmental Protection Agency. Since the amount of cement used is reduced, the treatment cost of the sludge can be reliably reduced.