Acid mine drainage and acid rock drainage is a rampant problem in the world today. The above photo depicts acid drainage at an abandoned mine in the Yukon Territory of northwest Canada. This mine shares a similar history to thousands of other mines throughout the world. It was in operation for six short years in the 1950s, producing gold ore. Its profitability eventually failed and it was abandoned. In the years following, the mine changed ownership several times, making it very difficult for the government to enforce treatment for the acid rock drainage that the mine created.
Clarifiers are expensive, to buy or repair, and their downtime can be costly in fines imposed by regulatory agencies and in community ill will. Regular maintenance, an annual inspection of the mechanism and an occasional touchup of the paint or coating system are simple and inexpensive proactive steps that will usually prevent most problems. Three components of all clarifiers require maintenance: the effluent system, the sludge removal system and the drive. The effluent and sludge removal systems require maintenance only occasionally, whereas the drive requires regular maintenance.
Category: Clarifier Maintenance
Mine backfill is defined as the material used to fill the cavities (i.e., stopes) created by underground mining. Backfilling can be a means to dispose of sludge and/ or tailings which may contain hazardous materials and to reduce surface environmental impacts by storing tailings underground.
Category: Mine Backfill
The minerals industry has faced increasing pressures in recent years in the management of tailings streams. Environmental, economic and other factors have led many minerals producers to explore the technology of making and using “paste.” With the increasing number of installations worldwide, this technology has proved to not only be industry accepted, but economically advantageous. The ability of paste thickeners to produce a higher concentration underflow leads to significant water recovery and savings and also reduces the cost of containment structures.
Category: Paste Thickening
Numerous studies and papers have been devoted to the subject of thickener design and operation to achieve specified throughput and discharge densities. Mathematical models have been developed that present methods for sizing thickeners and predicting performance under varying process conditions. The compression effect of deeper beds on dewatering performance is a recognized phenomenon. This is one variable of many that are inter-related and influence thickener performance. For example in the steady-state, continuous operation of a thickener, if the solids feed rate increases and the bed level remains the same, the underflow discharge rate must increase with the result of solids concentration being lower. The interactions of these parameters are at the heart of thickener models. Knowing the bed depth is critical to maintaining stable thickener operation.