"The official order came through in July this year, but delivery and installation of the fans has now begun and will continue until March 2015," said Gavin Ratner, Director of MechCaL. The mines that will now benefit from MechCaL's technology include: Dishaba, Tumela, Bathopele, Khuseleka, Thembelani, Siphumelele and Twickenham.
MechCaL will be supplying close to 316 fans ranging from 22kW 762mm fans to the standard 762mm 45kW fans as well as a few of their 75kW 1016mm units for underground use.
MechCaL has become well known for its designs and unique use of technology to manufacture fans for the mining industry. Its patented design is coupled with the use of lightweight materials to create fans that boast increased efficiency, operational and energy savings, and lower mean time between failures.
Ratner explained that the type of existing fans being used underground at these mines are cambered plate fan designs that that are traditionally very inefficient. "At best they perform at 60% efficiency and have, in most cases, been refurbished numerous times resulting in a degradation of performance," he stated.
Unique technology
It was the unique technology that caught Anglo Platinum's attention, said Gerhard van den Berg, Group Energy Engineer of Anglo American Platinum. "We replaced 36 fans at our Union Mine with MechcaL fans as part of an Eskom Demand Side Management project. The success of the project prompted the company-wide roll-out of MechCaL fans," said Van den Berg.
He said that the fans installed at Union Mine were aerodynamically superior to the fans that were used before and were proven to save 19kW per fan when compared to the previous fans with the same service delivery. Van den Berg commented on MechCaL's ability to problem solve for its clients in the field saying: "Whilst the initial fans were made in composite materials, MechCaL then replicated them in steel, providing a much more robust solution while still maintaining significant power savings."
MechCaL's designs are said to have been proven to provide 80% or better efficiency in performance and deliver higher flow rates. This results in significant savings in power drawn from the electrical grid. Added to this MechCaL has developed advanced VSD systems, which incorporate intelligent control that will enable ventilation on demand for the secondary fans. These systems will actively control delivery to ensure optimal system savings through reducing - or at times increasing - fan delivery to ensure that the mines are properly ventilated at all times. According to Ratner, this will not only ensure that the correct flows, temperatures and gas concentrations are adhered to, but will optimise the efficiency of the entire system.
When discussing the specific fans set for installation Ratner described in detail their intentions for delivery on this project. "The majority of the fans will remain the 45kW units, along with about 70 75kW 1016mm fans. We have done numerous tests to prove that due to the traditional fans under delivery, the 22kW 762mm MechCaL fans could replace them resulting in huge electrical savings for the same air delivered. We have also looked at the possibility of changing the current duct sizes to reduce the airspeed in the ducts, and then also reducing the losses."
Significant savings
Ratner explained that when this change in duct sizes is coupled with an intelligent controller developed by MechCaL, significant savings are achieved. When working in underground space the constraint is the limitation to the duct size; however in most mechanised mines, the haulage sizes can accommodate the duct increase in areas required said Ratner.
All of the above technology, once implemented, will greatly benefit Anglo-Plat's mines, but Ratner believes that one of the biggest indirect benefits will be in the mines experiencing fewer production stoppages as a result of the fan's overall superior performance. "Yes, the MechCaL fan is very efficient, resulting in direct energy savings and, added to this, the long-term mean time between failure of the system results in maintenance savings, but what these also means for the mines is a reduction in production stoppages as work can continue even if the fan is not running."
Overall, Anglo Platinum is very enthusiastic about working with MechCaL said Van den Berg. "MechCaL has put optimised aerodynamic theory into practical use for the mining industry - almost like putting rocket science into practice; quite an achievement, in my opinion!"