Pasminco Smelter Tour: Port Pirie in the Mid North region of South Australia

The aerial view of Port Pirie, on the eastern side of Spencer Gulf clearly shows the two main industries that have sustained the town.

A cluster of massive silos emphasise Pirie's prominence as a vital port for exporting millions of tonnes of grain grown annually on the surrounding wheat and barley fields.

But the Pasminco Smelter, with its 205-metre stack dominates both the skyline and the local economy. Without it much of the sprawl of Port Pirie's outer suburbs would not exist. The Smelter is by far the largest employer in town.

Perched just opposite the mangroves on the Port Pirie River, the plant has for most of its life been closed to the public. But not any more - we joined a tour of the plant with guide Dirk Richards:

“This is what the blokes in the Pasminco Smelter wear to work everyday. I'm wearing this gear because we're going to go inside the plant and have a look around this amazing facility. But don't worry - if you want to come and do a tour of this plant you can jump on an air conditioned bus and tour the facility.”

The coach tour takes you around the plant and the wharves, which are lined with stacks of lead and zinc bound for markets interstate and overseas.

But to really understand this place you need to experience the heat of the blast furnace because everything that's shipped to this smelting operation will find it's way in here. There's something almost biblical about the inferno - a metallurgical purgatory where impurities are skimmed off as slag and the rest progressively refined at staggering temperatures.

Each metal will eventually solidify or "freeze" as the metallurgists put it, at different temperatures. Dirk Richards:

“Something like lead will freeze at a quite low temperature - something about three twenty eight is actually the melting point. But something like copper will have s slightly higher melting point and zinc will be even higher at nine hundred. We use that different temperature gradient to leave one metal as a liquid and take one off as a solid.

That’s how we can separate them. What we're doing here in the zinc rich slag, which sits on molten lead and as it comes out the mixture of the liquid the two separate based on the density. The lead goes off to this side and it contains copper silver and gold and the zinc goes to the other side to the zinc separation circuit.”

The lead's used in car batteries, the zinc for making galvanised iron; the silver's used in the processing of photographs and the copper for electrical supplies.

The blokes who work here - shoveling away accumulated buildup of various materials to prevent the furnace becoming blocked - can only do so for short periods because of the intense heat. Eventually they go into an air-conditioned room for a breather where they monitor the plant's operations by computer and keep watch on the closed circuit television screens, which capture all the drama in the world's biggest lead smelter.

It's also one of the most complex smelting operations in the world. Most smelting plants refine only one or two products. Pasminco Port Pirie gleans five metals, various alloys and other essential by products like sulphuric acid from the ore that arrives from the mines at Broken Hill. Dirk Richards:

“This is the nearest port to the Broken Hill mines. The original smelting operation was done at Broken Hill but then it was found, for export reasons that they needed a port and so the smelter was established at Port Pirie. So it's about one hundred fourteen years old.”

Those who work here probably have a better handle on the spot price of various metals than most South Australians. After all, the future of the plant and therefore their jobs depend on it - and has done so for a very long time. Dirk Richards:

“It's not unusual for us to have four generations of families working… having worked at the smelter.”

Tours of the Pasminco Smelter operate every Wednesday. To book contact the Port Pirie Regional Tourism and Arts Centre on 1800 000 424. If you have any further questions please email info@postcards-sa.com.au