Reducing emissions with efficient pump technology.
One growing focus on CO2 emissions has pump users demanding optimal efficiencies from their pumping equipment. RMI Pressure Systems uses various technologies to achieve this with its high-pressure reciprocating pumps. The company’s S-range of plunger pumps are known in the mining sector and include the Trimax range of three-plunger pumps and the Quinmax range of five-plunger pumps. They feature solid ceramic or tungsten carbide-coated plungers, combined with Kevlar fibre seals to provide durable, high-pressure sealing.
The efficiency of the mechanical system is enhanced by RMI’s Active Performance Management software, which uses informed, data-driven responses to changes in load and system performance.
The S-range pumps reduce costs by using variable frequency drives (VSDs); these use demand-based operation, so they only consume the energy required based on the current system demand. This results in reduced energy costs and reduced CO2 emissions without compromising performance.
VSD operation allows for more controlled pump ramp-up and ramp-down, resulting in a smoother system operation and controlled top-up of accumulators. This reduces pressure spikes and wear on key components, as well as increasing system reliability and longevity. In contrast, fixed speed drives have a coarse response to demand, which leads to inefficient energy use; they also deliver high shock loads, which reduces system life.
The VSDs and PLC controllers can be tailored to specific site requirements, and this is coupled with RMI’s integral valve lifter technology – which yields huge potential energy savings particularly when unloading from system demand. Valve lifters stop the pump from moving the fluid, which reduces energy consumption even further. When added with the VSD, it allows the pumps to be ramped down to a very low speed. It also allows the pump to be ramped up to higher speeds without loading the system – thereby lowering the operating cost.
Industry demand
“Users of high-pressure pumps are increasingly focused on energy efficiency and sustainability,” says Kathryn Poke, RMI Pressure Systems’ general manager for Europe, the Middle East and Africa (EMEA).
Extensive testing on the pumps is conducted before delivery to customers, using dedicated test cells in the company’s Manchester production facility. The plant, which is powered by solar energy, results in reduced carbon emission when using these test rigs. During this testing programme, the company performs oil temperature and pressure checks, vibration monitoring, as well as the normal pump performance criteria. RMI’s pumps are also under a continuous development programme to meet the most demanding operating conditions.
The range of technical tests means that equipment and components can be put through as much as two million pump cycles – over periods of up to 160 hours – to prove their integrity. This is vital, as the pumps are used in robust and continuous applications such as steel making, where customers rely on them to deliver optimal uptime and safety. In these demanding and often hazardous environments, pump pressures can reach 350 to 400 bar – making any leaks or defects potentially disastrous.
SCADA technology also constantly monitors the pump and system health, allowing an early response to any operational deviation. The SCADA system will show any alarm activation from the pump station, which keeps downtime to a minimum as fault finding is simplified. The SCADA system will also capture data on the operating conditions of the pump station, and log this data for later review. Any anomalies in pressures or temperatures can be identified and attended to in a scheduled review – preventing any failures and loss of production.
Aussie rules
A key mining market for RMI’s solutions is Australia. Here, the company has successfully been building and installing its salvage – or rental – pump units to facilitate the moving of longwalls.
The significant capital costs of longwall mining equipment make its production uptime – and hence its efficient recovery and relocation – vital to mine productivity.
According to RMI’s director for sales and service in Australia, Huw Dodds, customers usually hire the reliable and versatile RMI units in pairs – one to power down the roof supports shields at the old coalface, and the other to power up the shields at the new face.
“However, over the past four to five months, we are seeing a growing trend in Australia towards hiring a third salvage unit to be located in an underground workshop,” says Dodds. “This allows repair and maintenance work to be carried out on the shields without having to take them above ground, which shortens the out-of-service mining time and saves both money and resources at the mine.”
A standard RMI salvage unit is fitted with the company’s S300 Trimax pump, driven by an on-board 110kW electric motor. This delivers a duty of 202 l/min at 208 bar, although these basic specifications can be adapted to suit specific customer requirements. The salvage units are used mainly for the shields, but can also provide hydraulic power to any other longwall items as required during the relocation.
“To assist our customers with the scheduling of their longwall moves, we work closely with them to ensure that our units and service personnel are available when they need us,” he says. “Flexibility and forward planning also help us in adapting the equipment to specific customer requirements.”
RMI’s service engineers are qualified to provide training for customers’ staff, and this is regularly done on-site for new and existing operators. The company also provides comprehensive documentation – including operation manuals in both soft and hard copies – for every rental period.