Abstract

At present, most of the desulfurization technology in the power industry adopts limestone wet desulfurization, and the cyclone is widely used in the wet desulfurization system because of its excellent performance as a high-efficiency classification equipment. At present, the cyclone is often used in the wet desulfurization system of limestone grinding classification system, gypsum dehydration system, wastewater pretreatment system. In addition, in the desulfurization methods such as the ammonia method, the magnesium method, and the carbide slag, it is necessary to perform the fractionation and concentration treatment of the desulfurization product using a cyclone.

Project Application

1. Limestone grinding and classification system

The cyclone and ball mill form a closed-circuit grinding system to classify the limestone slurry, overflow to make 20-30% limestone slurry, and then pump the limestone slurry to the absorption tower; the cyclone underflow returns to the mill for regrinding.

Design data: limestone cyclone has a regular feed concentration of 47%, an overflow concentration of 25-30%, and an overflow fineness of 325 mesh (44μm) of 90%.

2. The gypsum cyclone is used for the initial concentration of gypsum slurry in the absorption tower.

The gypsum slurry concentrated by the gypsum cyclone unit is fed to the vacuum belt dehydrator after being buffered by the gypsum slurry tank from the lower part of the cyclone. A part of the overflow slurry from the gypsum cyclone flows back to the absorption tower, and the other part is transported to the wastewater cyclone by the wastewater feed pump.

Design data: gypsum cyclone regular feed concentration 15% ~ 20%, underflow concentration 45 ~ 55%

3. The water in the slurry of the desulfurization device will enrich heavy metal elements and Cl-in the process of continuous circulation. On the one hand, it will accelerate the corrosion of the desulfurization equipment, on the other hand, it will affect the quality of gypsum. Therefore, the desulfurization device must discharge a certain amount of wastewater into the wastewater treatment system. The wastewater cyclone is used as the pretreatment of wastewater. The overflow of the cyclone enters the wastewater treatment system, and the underflow returns to the filtrate water tank or to the absorption tower.

Design data: wastewater cyclone regular feed concentration 3% ~ 7%, overflow concentration 1% ~ 3%