Allan Jansen or Mark Baird
Tel: 011 673 9946
Fax: 011 258-8511
Postal address: PO Box 1701
Gallo Manor, 2052
Physical address: Building 2
Country Club Estate
Woodlands Drive
Woodmead

By Robyn Joubert

Head in the clouds

First sale comes quickly for Moyomnandi, ECOSERV’s own stack sampler

ECOSERV’s stack sampler has made short work of converting a test drive into a sale. The locally manufactured prototype was set up for testing at Xstrata’s Wonderkop plant and didn’t take long to convince the company to purchase a unit of its own.

Tommie Hurter, Xstrata Risk Management Superintendent, says the ferro-alloy producer was impressed with the durability and mobility of the unit, which means they can move it to test different stacks. Xstrata’s Wonderkop plant has six open furnaces with positive pressure baghouses and ECOSERV has long been involved in analyzing their emissions.

The stack sampler, called Moyomnandi (meaning ‘clean air’), was developed and built over the course of two years by Mark Baird and Allan Jansen. Mark, with an MSc in Chemical Engineering, concentrated on the software and Allan, with a BSc Eng (Elec), built the hardware.

ECOSERV believes the fully-automatic stack sampler is the only locally manufactured unit of its kind. It costs in the region of R200,000 to R250,000, slightly less in price terms than imported versions but with significant advantages.

The unit runs the software off Excel, which simplifies data collection and does away with the need to record data on site and capture this at the office. It is built so you can expand on it to take other inputs and provide additional information which typical stack samplers can’t do. The unit is also an improvement on samplers that are not fully automatic as it continually takes measurements of the gas stream and makes adjustments to the sampling rate.

“With a non-automatic sampler, even if the sampling traverse points and velocities are correctly determined, variations in the process are not apparent until the next readings are taken, with the resultant increase in the absolute isokinetic variation,” says Allan.

But perhaps the strongest selling point is the technical support that comes with the unit. “Most overseas companies develop proprietary electronic components so spares and service is a huge problem if you buy imported samplers,” says Allan. “We have gone for more generic components that are readily available off the shelf. This means maintenance costs are reduced and parts are far more readily available. If there is a fault, you don’t have to wait six to eight weeks to ship the machinery to the USA for repair.”

The stack sampler was named Moyomnandi, meaning ‘clean air’, the fruit of a competition amongst ECOSERV staff.

“Thandi Mjoli, who presently heads AER, came up with the name,” says Allan. “Stack sampling assistant Bethuel Komape suggested we use a giraffe as the logo as the whole contraption operates in much the same way as a giraffe.”

The sampling probe/nozzle/filter/condenser assembly is typically located way up in the air and is connected to the heavy sampling pump, control cabinet and laptop computer at ground level by way of an ‘umbilical’ arrangement of an air hose and cables.

Now that Moyomnandi has been christened, it can get on with the task of carving out a good name for itself.