Water Management is that to win the same amount of material that was previ-ously extracted requires more mining, which produces more tailings. The mining industry must figure out where to dis-pose of them. Many mining companies are forced to enlarge their tailings storage facilities. In addition, there must be an environmentally sound plan for replacing the water that is extracted. freshwater costs as the recovered water can be reused. It’s difficult to acquire permits for mining, and even when the permits are secured, that doesn’t mean that land is avail-able. The term NIMBY has become common in the mining industry. It means “not in my back yard” and reflects the resistance from the public in general to mining operations near residential areas. With the shortage of space, miners are competing with communities, agriculture and industry for space. And government is less likely to make more land available for mining. One solution to the shortage of space is to remove more of the water using separation processes. That way, more of the desired materials can be produced, which saves a large per-centage of the space required. 3. Compared with a filter press, a decanter requires a third of the footprint. Sometimes it’s even smaller. The space required is not much more than two pick-up trucks. (e.g. 7 x Z92 Decanters -> Area required = 30 meters x 50 meters (1,500 m²). 4. Filter presses require a permanent, concrete base and enclosed structure. Decanters require no cover or per-manent structure. Electronics are protected within a shipping container next to the unit that is dust proof, wind proof, and temperature controlled. The system sits on a highly portable metal skid and can be moved easily. It’s possible to install centrifuges without covers because they are durable and resistant to extreme temperatures. 2. There is also a high percentage of high-water recovery. Turbidity of reclaimed water may be between 30-50 NTU (Nephelometric Turbity Units). Stricter Regulations Government regulations for mining have become stricter through the years. In many European countries, the sand and gravel pits are restricted to pulling up only a certain amount of water and none of it can be put back into the groundwa-ter for fear of contamination. Mining companies around the world have built large dams that are becoming overloaded. 5. Decanters are cost efficient. Because they are fully automated and can run continuously 24/7, decanters require one-tenth the number of operators that a filter press needs. With the increase in stricter regulations, some governments are also sensitive to the “social license” to operate – com-pliance is required without specific regulations, based on the safety and environmental concerns of the community. A big part of the social license to operate involves water conservation. 6. Decanters have sophisticated plug and play solutions in a standardized system. There are also optional features such as placing a centrifuge on a platform or adding a conveyor to remove solids. 7. Decanters are easy to transport. The low profile, rel -atively small size is designed to fit standard road trucking, making them easily transported to another mines. 8. Decanters have reliable and proven technology with high availability. Improvement of Operational Efficiency There are limited options available for mining operators to improve profits. Miners are only paid for the minerals pro-duced, but now more effort is required to get them. Efficiency and productivity become directly connected to profits, cre-ating a continually rising focus on improving operational efficiency to help reduce costs. Improve Water Recovery 9. Decanters are easy to maintain. They are resistant against wear and corrosion, making them more effi-cient to operate and reducing maintenance costs. Some companies, like Flottweg, offer full aftermarket services that make maintenance and operation simple and wor-ry-free for the operators. 10. Filter presses use +20% less electricity, but because of the robust mining design, decanter centrifuges are still more cost efficient to operate and have higher productivity. 11. Another specific advantage a decanter centrifuge has over a filter press is that there is no filter cloth which can become blinded with fine particles. This means that the flow rate through a centrifuge remains constant. Decanter centrifuge technology has become a choice for recovering water in the processing of ore and minerals. There are several advantages to using decanter centrifuge technol-ogy for mining operations: 28 • ROCKproducts • July 2022 1. Typically, when materials are spent through a decanter, 70% to 75% of the water will be removed without too much effort. That process significantly reduces www.rockproducts.com
Rock Products July 2022: Page 28
