Sulphur dioxide stinks. I should know – I come from Wollongong – the home of the Port Kembla steelworks. We always knew when the winds blowing from the south because you could smell the steelworks. That is, you could smell the sulphur dioxide.
It’s an awful, musty, industrial type smell, and it’s no wonder the residents of Cockburn are unhappy with Cockburn cement. They have every right to be. The issue is not toxicity, its quality of lifestyle, and the legitimate desire to walk outside and not feel as though you are in the middle of a manufacturing plant.
The reason that sulphur dioxide creates this feeling, is that it is a very common industrial gas. There are essentially two sources of it. The first is from the combustion of coal, which contains a fair bit of sulphur, and the second one is from the smelting of sulphide ores, a common thing in Western Australia.
This was a huge problem at the Kalgoorlie nickel smelter, and it created such angst in the town that they had to do something about it. They chose a wet sulphuric acid process, whereby the sulphur dioxide is converted into sulphuric acid, which they can then sell, so they killed two birds with one stone.
Sulphur dioxide is still a problem at the Gidgee roaster, about 80 km to the north-east of Kalgoorlie. I have actually been inside their main control room, where they have a very sophisticated weather monitoring system. The centrepiece of the display is the wind data, and there is a no-go zone in terms of wind strength and direction, at which point they must shut the roaster down, as the fumes will be blowing over Kalgoorlie.
But back to Cockburn cement. Their sulphur dioxide come from the massive amounts of coal that the have to burn to beat their kilns hot enough to convert the limestone to lime (about 800°C).
But of all people they have the least excuse in terms of dealing with the problem, as one of the simplest methods to overcome it is a wet scrubbing method involving lime, which of course they have plenty of.