Experimental research on the classification performance of the hydrocyclone with conical feed part

The overflow granularity often became coarse when fine particles were classified in a hydrocyclone.In order to solve this problem,a new type of hydrocyclone with conical feed part was put forward and an experimental study on its separating performance for fly ash grading was carried out.Different structural and operating parameters including the apex diameter,the inlet pressure and the feed concentration have been used in the experiments.The experimental results show that,as the apex diameter increases,the underflow concentration decreases but the productive rate increases,and the comprehensive classification efficiency is improved obviously.When the inlet pressure increases,the overflow concentration decreases while the underflow concentration and the classification efficiency increases at the same time.However,compared with the increasing overflow and underflow concentration,both the underflow production rate and the classification efficiency gradually decrease with the increase of feed concentration.In conclusion,the grading granularity d₅₀ is 54μm,and the classification efficiency reaches 88.66% by quantity and 49.50% by quality when the apex diameter is 18mm,the inlet pressure is 0.06MPa and the feed concentration is 16%.Moreover,the －45μm particle content is above 88%,which meets the requirement of the first grade fly ash standard well.