METHOD AND DEVICE FOR DRYING WATER-CONTAINING SLUDGE

• Main Authors: NAKAJIMA HAJIME, IGARASHI MISAO, NAGAYOSHI GIICHI
• Format: Patent
• Language: English
• Published: 26.01.1993
• Subjects: BLASTING; CHEMISTRY; CRUSHING, PULVERISING, OR DISINTEGRATING; CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; DRYING; DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM; HEATING; LIGHTING; MECHANICAL ENGINEERING; METALLURGY; MILLING GRAIN; PERFORMING OPERATIONS; PREPARATORY TREATMENT OF GRAIN FOR MILLING; TRANSPORTING; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE; WEAPONS

PURPOSE:To dry and pulverize water-contg. sludge without using the conventional crusher by drawing off a material to be treated, which has been partially lumped and settled at the lower part of a fluidized bed, to the outside of the system, coarsely crushing the material which is returned to the fluidized bed and separating the material having a specified particle diameter by a dry dust separator. CONSTITUTION:The grains of quartz sand or the like having a specified range of diameters are used as the fluidized-bed medium of a fluidized-bed dryer 1. The fluidizing air F is blown into the fluidized bed 2 at the lower part of the dryer 1 to violently fluidize the quartz sand as the medium and the supplied sludge, hence the sludge is crushed, and the water contained in the sludge A is vaporized by the heat produced by a hollow sheet-type heating element 12 inserted into the fluidized bed 2. The lump material is drawn out of the lower part of the fluidized bed along with the fluidizing medium and classified by a classifier 13, the coarse grain left on the screen is crushed by a roller mill 4, and the crushed material, subsieve quartz sand and fine sludge are sent to a mixer 5. The grains are collected by a cyclone 6 to obtain a product dry sludge C.