Recovery of clean coal from the contaminated waste of Quang Ninh province - Viet Nam

The contaminated waste is a by-product generated during coalmining process. This type of products may contain more or less 20% of cleancoal, thus their ash content may vary in a wide range of 60 to 80%. Thiswaste normally is stockpiled separately at “temporary disposal dumps” asthey would not be regarded as waste in the full meaning, however, it is verysensitive for the miners who attempt to process such a waste. Based on theresults of the coal characteristics survey at some surface coal mines ofVietnam, the studying authors have collected a large quantity ofrepresentative samples, such as Ha Tu, Nui Beo, Tay Khe Sim, Ha Rangmines and have carried out a number of experiments using low cost andhighly efficient separating equipments. These are semi-industrial movablescreen jig, fluidization separator, some samples of -0.5 mm size usingflotation method. Products of processing include clean coal, which has ashcontent obtain quality standard of Viet Nam (clean coal is consumed easily)and tailings have ash content over 80%, which can waste. The study resultsshowed that the application of the new machines could allow significantrecovery of clean coal from the contaminated waste. This may significantlycontributes in reduction of environmental pollution while ensuring theproduction viability and economic efficiency for the miners.