HUNTER VALLEY OPERATIONS NORTH PIT - COAL FINES SLUDGE DEWATERING
The Yancoal Australia Hunter Valley Operations (HVO) is a multi-pit open-cut mine producing more than 13 million tonnes of thermal coal and semi-soft coking coal using dragline truck and shovel methodology. The raw coal that is mined is called the run-of-mine (ROM) coal is delivered to the Coal Handling and Preparation Plant
(CHPP).
Typically 17-20% of the ROM coal delivered to the CHPP is considered waste. This facility washes the coal of soil and rock, crushes it into graded sized coal, stockpiles and prepares it for transport to market. The more of this waste material that can be removed from coal, the lower its total ash content, the greater its market value and the lower its transportation costs.
"... slurry can either be processed in a series of centrifuges and cyclones to remove water and separate the coal fractions however this is an expensive mechanical process. An alternative is to use dewatering technology using Geotube dewatering containers and Yancoal Australia decided this was the best option for the HVO north pit at Ravensworth."
The sludge was then pumped into eight Geotube dewatering containers supplied by Geofabrics Australasia. These tubes, contained in a large bunded area adjacent to the settling pond, had a circumference of 36.6 m and were 30.6 m in length with capacity to retain a dry volume of approximately 1,000 m3 of dry cake.
