Brief introduction to the System

The underground dense-medium shallow trough refuse discard system, developed and installed by Kedi, has made a breakthrough to the traditional process of lifting all mined materials aboveground and separating the raw coal and discarding the reject aboveground, realizing the underground separation of run-of-mine coal and underground discarding of the refuse as well as refuse backfilling. This solves the problems of effectless transportation of the refuse as well as the spontaneous combustion and environmental impact of refuse stockpile on the ground. It fills in the gap of underground dense medium separation technology in domestic coal mines, and is the first of its kind in China. With its patented core technology, the system is leading the domestic market and reaches international advanced level. It is a revolutionary innovation of the traditional production process in the coal mining industry.

System characteristics

Underground refuse discard comprises four stages: 

The first stage is run-of-mine coal classification. After the run-of-mine coal is screened, the extra large pieces are rejected, the medium size material is to be processed, and the fine coal is the product.

The second stage is material separation. The material enters into the shallow trough, refuse sinks at the bottom of the trough and is discharged by the scraper; The clean coal floats up and is transported out by scraper conveyor to be rinsed.

The third stage is medium recovery. The qualified medium from the rinsing screen goes to the medium sump for reuse. The dilute medium is sent to the magnetic separator, and the concentrate is sent to the medium sump, and the tailings enter the tailing sump.

The fourth stage is slime water treatment. The slime water, after thickened, is pumped into the press filter for dewatering, and the filter cake goes to the cleaned coal, and the thickener overflow and the filtrate go into the circulation water sump.