This is the ninth of ten stories about how coal was mined in North Lanarkshire.
Coal is usually found deep in the ground and for centuries people have gone to great lengths to get it, using ingenuity and taking enormous risks.
Coal fuelled the industrial revolution. It was burned to heat homes, to power steam engines, to make iron. It could also be heated to extract gas and oil. In fact, coal gas used in most homes until North Sea gas was discovered. Scottish coal production grew from 2 million tonnes in 1800 to a peak of 42½ million in 1913.
Lanarkshire was home to Scotland’s biggest coalfield and at its peak in 1910 the county was home to about 200 coal mines.
Sorting, Washing & Waste
When the coal is brought out of the ground it comes mixed with stones, soil and other things that are not wanted. It also comes in different sized lumps which are needed for different purposes and need to be separated.
Coal picking was one of the most important, not to mention most tedious jobs in a coal mine. After the coal had been brought to the surface it was sifted and then put onto a conveyor belt for men and women to pick out the stones as it went past. Women tended to do this job as they were forbidden to work underground while men who had been injured underground might be put to work coal picking if they were unable to work below ground.
The waste from mines could sometimes be used to pack empty underground workings but most was dumped on the surface in huge heaps called ‘bings’. These cone-shaped hills were once common all over Lanarkshire and central Scotland – you can still find some today. You can also trace many of the overground railway branches, often known as waggonways or tramways over the Lanarkshire countryside.
After the coal and rock waste had been separated the coal was then washed to remove fine dirt.
There were two main ways of washing coal: ‘froth flotation’, where the coal floated to the surface of a tank of water with a layer of oil on top, and ‘settling’. In the latter, because particles made of different materials had different densities, when put into water they would sink to different depths, separating out. Both methods of washing were in common use in Scottish collieries.
One product of the washing was a goo containing coal called ‘wet gum’. When part-dried this could be burned in the pit boilers.
By the time deep coal mining ended in Scotland most coal was sent to power stations which could burn dirty coal. This meant that the coal did not need to cleaned very much.