In response to the ongoing power crisis in South Africa and the global need to reduce carbon emissions by improving energy efficiency, Integrated Pump Technology’s key accounts manager, Justin Bawden, talks to MechChem Africa about some easily implementable dewatering solutions that mine and process plant operators can adopt.
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Integrated Pump Technology offers a wide range of pumping solutions for dewatering, sludge, slurry, wastewater, dredging and water transport/circulation and recycling applications on mines and minerals processing plants. “We specialise in Grindex submersible pumps that can operate from a pond floor or suspended above the floor using one of many pump flotation devices.
“We can also offer pump cages as a means of additional protection for pumps that operate in rugged environments and, apart from standard cast iron and aluminium pump units, we also offer stainless steel solutions for use with corrosive media,” begins Justin Bawden of Integrated Pump Technology.
In addition to its electrically driven range, the company offers a range of diesel driven units and pumps mounted on skids or on trailers, for ease of mobility to site. “We can supply fixed and mobile installations and our diverse range enables us to customise a solution to match the needs of mine and plant operators,” he tells MechChem Africa.
The pumps themselves are mostly Grindex submersible slurry pumps from Sweden, which can be configured differently depending on the pumping media and the specific plant needs. “We also have Faggiolati pumps, which are an Italian brand that is better suited to raw water applications. They feature cutter impellers that can chop up solid or fibrous materials to enable them to be passed through the pump without clogging,” Bawden explains.
Turning attention to the energy crisis in South Africa, he says many of our mines are now starting to produce their own energy in order to supply emergency demand during loadshedding. “Where energy capacity is a problem, we provide added assistance by supplying mobile diesel driven pumps. Some locations on mining sites don’t have an easy connection to power, so diesel driven pump units are the only option. In areas of the mine where there is a lack of power, the need for diesel driven pumps is critical, particularly when required for emergency use to prevent flooding or ground contamination
“While energy saving is a priority, mine dewatering or plant water transport requirements place limits on how much can be done without sacrificing production targets or onsite safety. In most cases, pumping must carry on, regardless of the energy required. While meeting plant needs, though, it is still possible to adopt more energy efficient technologies and power management options,” he continues.
Grindex pump units are designed to meet their duty requirements using the minimum amount of energy necessary. “These fully insulated, protected and submersible pumps raise the bar in terms of energy efficiency. Many competitor pumps require far more power to achieve the same duty as the Grindex pumps, which also offer better reliability,” says Bawden.
The operational expense of running pumps is mostly related to the cost of the energy being used. This far outweighs the capital costs of buying the pump. “We did a case study for a mine in Rustenburg where we compared the total costs of buying and running one of our Grindex units to a couple of the units they were using on site. The difference was astonishing. The operator was shocked to see exactly how much the old pumps had been costing them to run.
“Buying a more expensive but more efficient Grindex pump can save an operation a massive amount of energy and money over time – and the energy and cost savings start to accumulate from Day 1 of switching,” he says, adding that payback periods on the capital expense of an efficient pump can be as little one year. “In the long run, though, a high efficiency pump solution that is well matched to specific pumping requirements, can save a company an exorbitant amount of money.”
The Grindex submersible range is also renowned for its plug-and-pump capabilities through its SMART electrical surveillance system, which means there is no need for an external electrical start-up box for pumps units of 18 kW and below. The SMART system’s phase-failure guard protects against phase loss, a temperature guard stops the pump if overheating is detected, and the unit automatically restarts pumping when a detected fault is cleared. Phase control also ensures that the impeller turns in the right direction.
Integrated accessories such as the SMART surveillance unit, along with add-ons such as water level regulators, not only better protect the pump, but they are automatic, so they manage power use better, giving pump users peace of mind with respect to protection and energy use. “The SMART surveillance unit embedded in Grindex pumps is also 100% compatible with generators. This ensures that, even during extended periods without mains, the pumps can continue to operate reliably and efficiently, preventing downtime or production loss,” Bawden adds.
Describing the energy saving role of a pump level sensor, he says dewatering pumps can automatically be switched off when the water in a pond or sump reaches a safe level and, as soon as the level rises, the pumps will automatically switch on again. This improves reliability and minimises unnecessary energy use.
Pumps that cannot access features such this will continue to pump regardless of the water level. Eventually, no water will be pumped, but the pump will continue to operate on the far left of its curve. Not only is this a waste of energy, but it will also cause the pump to overheat, potentially causing damage,” Bawden points out.
Most important is that the pumps being used are well matched to the duty required by the application: primarily in terms of flow rates and pressure heads, but also in terms of the specific media being pumped and the surrounding environment. “We like to visit a site and analyse the pumping requirement before coming up with a solution.
This allows us to make the best recommendation possible for matching specific onsite needs and the duty, configuration, performance and efficiency required of the Grindex pumps. Our approach is to carefully consider the pump application and all the factors involved to see how they may affect the whole pumping system. “In many of the surveys we have conducted, there is large 45 kW pump, for example, operating in an application where 18 kW would be sufficient. The extra pumping power is just wasting energy and, over time, costing a fortune. In terms of safety factors, it is more efficient, more reliable and less expensive to buy a second standby pump than to install a pump that is twice the necessary size.
“The most energy efficient solution will always be the one where the pump units meet the application duty at minimum consumption – and right-sized Grindex pumps can almost always outperform competitors,” Bawden notes, adding that right sizing pumps to operate at their best efficiency also maximises pump reliability and extends service intervals.
Pumps do wear, however, so a planned maintenance programme is necessary to maintain pump efficiency. “If mostly pumping clean water, then service intervals can be longer, but abrasive slurries with stones and grit will cause impeller wear. Then a timely service programme is advisable to find out how much the pump duty and efficiency has been compromised and to restore it to its best possible condition.
“It is always good to check that a pump is still running as expected. At Integrated Pump Technology we have a fully operational service facility with testing equipment and a test bay where we can run a pump to make sure it is operating on its pump curve at best efficiency. If not, we offer a full range of repair services, from installing a basic repair kit to doing a full pump refurbishment to OEM specifications.
“It is never worth taking shortcuts. A refurbished pump from Integrated Pump Technology looks and performs as if it were brand new,” concludes Justin Bawden.