The harsh environment and the demanding industry requirements of gold mining pushes pumps to their limit, and selecting the best package sometimes means making hard choices between multiple suitable solutions.
Kelair was approached by a consulting engineering company that was making enquiries about a pump package for a gold mine.
The Kelair team looked at the situation and came up with two options that would meet the client’s requirements.
The mining company wanted to upgrade a hydrochloric acid (HCl) dosing pump package for use in a gold mine.
The pump was required to handle a 32 per cent HCl solution in an ambient temperature of up to 45˚C. The specific gravity required was 1.15, a flow of 0.8m³/hr, and a total dynamic head of 33.2m.
The mining company had originally used an air-operated diaphragm pump, but problems with noise, reliability and dosing accuracy led the company to request an electric drive option.
Kelair looked at the situation and assessed the various options. A helical rotor pump wouldn’t be acceptable due to the exotic materials that would be needed to handle the hydrochloric acid solution and the pump required a mechanical seal, which Kelair wanted to avoid.
Eventually, two solutions were offered to the client. The first, an OBL simplex diaphragm metering pump with non-metallic head and valves. The pump had a stroke actuator, which allowed for flow to be adjusted with a 4-20mA signal.
The second option was an Albin hose pump, which could adjust flow by using a variable frequency drive (VFD) to control the speed.
Kelair Regional Sales Manager for WA, Michael Charnley, said the diaphragm head metering pump was certainly better in terms of accuracy, but had several drawbacks.
“The stroke control requires a 240v single phase supply but the motor is 415v three phase, so when it comes down to it, the pump needs two power sources.
“Also, because you have a stroke controller on the pump, you have electronic controls situated outdoors in a bunded area of a mine, which is a really tough environment.”
Mr Charnley said that as the Albin hose pump delivered liquid in a fixed volume each rotation and there was no slip in a hose pumps, it was excellent for applications in which perfect accuracy was not a priority.
The Albin pump has a ductile iron construction that contains hardly any moving parts, and has no seal, diaphragms or valve balls.
Mr Charnley said, “With the Albin, the acid gets squeezed through a hose, and the only parts that the liquid touches are the ethylene propylene diene monomer (EPDM) rubber hose and the polypropylene inserts.”
The Albin pump is also capable of dry running and self-priming, though these functions were not strictly required for the application.
The Albin hose pump’s initial cost was lower than the OBL diaphragm head metering pump.
Kelair’s client eventually went with an Albin 25mm ALH25 pump running at 48rpm. The pump is able to continuously maintain the required flow and is expected to have a long hose life.
A SEW reduction box and a TECO 0.75kW mining spec motor were also fitted onto the Albin pump frame.
Mr Charnley said the Albin was an excellent choice both in terms of performance and price.
“Where the hose pump really shows its superiority is in its durability and its simplicity. With less auxiliary equipment and fewer parts to wear out, the pump is easier to maintain and will last much longer.”
Mr Charnley said the pump setup had shown to be robust and reliable since its installation and has not required any spare parts or maintenance.
“The client has been extremely happy with the results of the pump package and Kelair’s expertise and support.
“Kelair has a commitment to work with their customers to produce a quality package designed for the individual application.
“We really weighed up the specifics of the situation came up with two really good options. In the end, we really delivered and the client got the best solution,” Mr Charnley said.