Abstract: In order to reduce the impurity content in iron concentrate and improve the grade of iron concentrate in Dahongshan No.2 concentrator，CH-SWCXJ2200L automatic elutriation magnetic separator was introduced to carry out engineering technical transformation. The industrial test and production prac‐ tice show that the elutriation machine is used to replace the original three-stage wet drum magnetic separa‐ tor for quality improvement and impurity reduction. The tailings of the elutriation machine are recovered by the salvage machine. Under the condition that the feeding grade of 62.97%，the concentrate grade of the el‐ utriation machine reaches 67.30%，which is 0.99 percentage points higher than that of the original three�stage magnetic concentrate. The SiO2 content is reduced to 4.26%，and the operation recovery rate is 96.47%. At the same time，the content of harmful elements such as potassium and sodium is significantly reduced. It not only improves the product quality，but also brings significant economic benefits to the enter‐ prise. The annual direct economic benefit is 6.366 8 million yuan，which has good promotion value.

Key words: elutriation machine, quality improvement and silicon reduction, magnetic agglomeration