How to Improve the Efficiency of Spiral Classifier

Date:05/12/2015 02:03:13

Materials after entering into the spiral classifier from the inlet and being scattered on the spreading plate, fall into the selecting airflow. The rotation velocity of the screw not only affects the overflow particle size, but also affects the transmission ability of grit. The fine powder is expelled from the central pipe, and collected by dust collector. The faster the speed, the higher the yield of sand return meter. But because the stirring effect on the ore pulp increases, the amount of coarse particles mixed in the overflow grows. The separating airflow mainly comes from dusty gas, tangent to the primary and secondary airflow inlet and the fixed guide vane, and then enters into the powder selecting area.

Therefore, when choosing screw rotational velocity, it is necessary to know the requirements on overflow fineness and sand return yield rate. The secondary ore grinding or fine grinding process requires finer overflow products, so the rotational velocity of the screw should slow down a bit. The cage rotor composed of coarse and vertical blades and horizontal blades, maintains a certain pressure difference inside and outside in the height of powder selecting area through rotating.

Materials from the top to the bottom, the coarse powder is separated by the primary and secondary airflow, offering a chance for each particles to be selected repeatedly. Then materials will be separated by the third airflow on the bottom, and discharged from the bottom of the machine.

Spiral classifier is an important adjusting factor in the operation of ore pulp density, which is used to control the classifying overflow fineness. Generally speaking, the lower the pulp density is, the finer the overflow particle will become; Otherwise the overflow particle will get coarser. Because in thick pulp, the high viscosity of the pulp will hinder particles from settling, leading to the sedimentation velocity slowed down, which makes the overflow granularity of the spiral classifier coarsens.