With the rapid expansion of mining sites in remote locations, development companies are faced with the challenge of reducing the impact of big run-off streams and metal-laden wastewater on the local environment. There are many hurdles to cross with water management for this sector. Several mines need large quantum of water, and mining waste is a potential pollutant.
Wastewater from extractive operations (coal, bauxite, copper, silver, gold, diamonds, precious metals, iron, lead, magnetite, limestone, nickel, oil shale, phosphate, rock salt, uranium, tin, molybdenum) need to be managed properly to prevent any soil or liquid pollution emerging from alkaline or acid leaching with regard to heavy metals.
When the right system is put in place, mining water treatment services are easily managed. But the energy and water challenges for the industry will need innovative solutions for the protection of water resources and reduced emissions of carbon dioxide.
Water is crucial for all mining operations. In case of some locations, substantial rainfall can cause acid run-off from surface mines, tailing piles and mine drainage, thus polluting rivers and streams. In dry locations, the processing and mining of ores take up a huge quantum of scarce supplies of water and can cause pollution of groundwater using toxic chemicals.
Water treatment scenarios in the mining sector involve the following:
1) Treatment of domestic wastewater for permanent or temporary mining camps.
2) Treatment of run-off of surface water.
3) Treatment of toxic wastewater that has been generated during mining operations.
4) Treatment of wastewater for reutilization in dust control in roads or for landscaping.
5) Treatment of wastewater for releasing in surface water or injection into groundwater.
6) Mitigation and remediation of wastewater during the closure of mines.
Reuse of Wastewater
Several mines worldwide are located in regions with stressed supplies of water, and also, such operations have degraded whatever little water resources that are accessible. To prevent additional contamination of the environment, such companies can offer advanced mining water treatment services, which produce water that can be reused.
With modern technology, mining companies can do protection of local sources of freshwater by treatment and reuse of mining wastewater for drinking water, dust control, irrigation and landscaping. This helps protect local water sources, adheres to stricter environmental regulations and reduces the cost of disposal of wastewater.
Decentralized Treatment of Wastewater
Building up a water-delivery infrastructure from remote mining areas to feed a central plant for water treatment would be time-consuming, costly and need navigation of tough issues of right-of-way. Hence, extractive operations usually need some mode of decentralization of wastewater processing.
Advantages of decentralization are:
1) Reduced capital costs.
2) Low emissions of carbon dioxide.
3) Low energy costs and energy needs.
4) Quicker start using containerized treatment.
5) Reduced maintenance needs.
Energy Efficient Water Treatment
Treatment systems for wastewater from mining operations may run on electrical energy. Traditional treatment of activated sludge needs high power for operation of aeration pumps. Modern technology which lowers this need can make mining more environmentally sustainable.
These are all some aspects of treatment wastewater generated by mining.