Producing Slurry

We're progressing in leaps and bounds with ore commissioning. The last 5 days we have been running ore in one of our two HPGR's, through the ball mill, onto our Concentrate Thickener. It's early days yet, however it's good to be operating the plant and making slurry.

This photo shows a magnetic separator in operation. These rotating drums have internal magnets installed in their lower third, which "shuffle" iron particles in the direction of rotation, while non-magnetic particles flow in the other direction. Here you can see magnetite dropping into the concentrate launder.


In addition to ore trials, we have also been performing pre-commissioning work on the Geho slurry pump. It's a monster 3 piston / diaphragm positive displacement pump powered by a 1.1 Mega Watt motor. There's a cool animation of the pump here.

Ore Trials

We are now crushing ore with the HPGR's, and trialling our screens and magnetic separators. It's not long now before we commence grinding with the Ball Mill.

We have had a few teething problems - but that's all part of commissioning. The Electrical and Instrument side of things has gone really well so far, with only a few calibration issues with a tramp metal detector. Tramp metal detectors are designed to pick up over-size iron objects, like bolts, on conveyors, thereby protecting the equipment downstream of the conveyor. Calibrating these detectors to pick up iron objects in a stream of iron ore has got it's challenges, as you may expect.

Here are some awesome photos taken of the site at dawn, by Dave Barringhus. Enjoy!!!

The Worlds Biggest Chocolate Wheel...

Things are starting to happen at work. We have now bumped all our High Voltage motors, and expect to run our first water circuit this weekend.

In tandem to this, we also hope to spin the Ball Mill very soon. The mill is the beige coloured drum in the centre of the photo. After we have proven the lubrication systems for it's trunnion bearings and ring gear, it will be charged (or loaded) with a few hundred tonnes of steel balls, each about the size of an apple, in preparation for grinding.

Grinding medium is produced by mixing the crushed ore from the HPGR's with water, then passing the mixture through a series of screens and magnetic separators, to leave sand sized magnetite particles. The mill will then grind these sand sized particles down to a slurry with the consistency of a thick-shake.

But anyway, back to the Worlds Biggest Chocolate Wheel. There are exactly 100 bolts joining each of the three cylindrical sections of the mill together. We have numbered the bolts near the ring gear, and put a marker on the ring gear casing. Numbers were sold at $10 each. When the mill stops after it's first spin, the number closest to the marker will be the winner, and the lucky person will take $500 (with the other $500 going to charity).

Fingers crossed for number 99!!!

A Trip to Melbourne

We spent last weekend celebrating the Winter solstice in Melbourne. The shortest day of the year is not something I'd normally give any thought, but it was reason enough to head over to Melbourne for an old friend's dinner party.

Dinner was at Fifteen Melbourne, the latest Jamie Oliver restaurant. We had the 6 course Vegetarian degustation menu, and accompanying wines package. I must admit I was pleasantly surprised with the excellent food and wine. The cooking shows and Fifteen series on TV had never really got my attention.

Managed to get down to the Burnley bouldering walls on the Friday afternoon, and ran a few laps on the 45 Degree white traverse. My stamina levels were surprisingly good, considering the last time I climbed routes was back in March. Also spent a few hours on Saturday thrashing myself silly on the easier problems at The Lactic Factory - it's such an awesome indoor bouldering venue.