Sulzer’s Flow division reflects on how pumping efficiency can meet the Australian mining industry’s evolving energy needs.
In the minerals and metals processing industry, ideal application conditions where a pump is operating at its best efficiency point (BEP) and the system is stable very seldom occur.
Wear and corrosion can quickly lead to a shortened life of the pump in demanding applications.
A deep understanding of the application, corrosive and abrasive characteristics of the fluid, flow demands and the process itself are key to meeting the customer’s requirements.
Corrosion and wear rates are not summable, and that is why pumps should be tailor-made for difficult liquids that are corrosive, or corrosive and abrasive at the same time. Innovations are needed for the development of efficient pumps with low operation and maintenance costs.
The worldwide industrial energy consumption is expected to increase by 42 per cent from 2007 to 2035, or at an average of 1.3 per cent per year.
Pumping systems account for more than 20 per cent of the world’s electrical energy demand and, in certain industrial plant operations, they can be responsible for 25–90 per cent of the energy usage.
Consequently, the minerals and metals processing industry continues to make large-scale investments that contribute to energy efficiency.
The task is rewarding, because with only a small reduction in energy consumption, significant financial savings can be achieved.
The investment also has a low risk, because cost savings will occur whenever the plant is running.
The Sulzer Ahlstar WPP wear-resistant pump design is not a heavy-duty slurry design. Its process pump hydraulics allows high-level efficiencies.
The difference to a standard process pump is that the flow patterns of wear-resistant pumps are specially designed to prevent abrasion in the hydraulic parts.
When targeting an energy-efficient pump solution, size, speed, type of drive, pumping system lay-out, seal and auxiliary equipment, and the optimal pump type must be considered for a comprehensive solution.
The best efficiency and further energy savings can be achieved by driving the wear-resistant pump with a variable speed drive (VSD) and a maximum diameter impeller.
This allows the rotational speed of the pump to be adjusted to achieve the desired head and flow for the process application. The efficiency improvement compared to a constant speed driven pump can be up to 10 per cent.
A VSD can also be added to existing pumps. Once installed, it can accommodate changing system demands, including potential future expansion plans without changing the pump. In addition to energy savings, this method also results in improved process control, better system reliability, lower maintenance costs due to reduced wear, and soft starter capability.
It is for this reason that VSD-driven pumps are becoming more and more common in the minerals and metals processing industry.
