I was so delighted with yesterday's satisfactory confirmation of shale oil distillation in Linn Park that I went out this morning for a walk along the riverbank for a bit of “shale spotting”. Even after last night's deluge there is lots of the stuff visible above the water level of the fast flowing White Cart.
The civil engineers at docplus.co.uk's “Linn Park, et al” site,
http://www.linnpark.org.uk/ have requested to share pictures with my White Cart Walkway web page
http://www.scotcities.com/cathcart/whitecartwalk.htm, to share any interesting finds in the park.
Hopefully we can now get back to the subject matter of the thread.
It is amazing that this mineral resource can still be found freely lying around 150 years after the peak production of shale derivatives. It is ridiculous to believe that it would not be exploited at the very time when scientific advancements were finding lots of new uses for the stuff!
Coal was easily worked in what is now the park The mills were mainly water powered but needed oil for lighting, lubrication and cleaning. Using this coal, the locally sourced shale and limestone could be processed for industrial uses, avoiding the heavy cost of transportation to this relative backwater.
The “Linn Park, et al” site,
http://www.linnpark.org.uk/ site has an extensive section about the geology and minerals of Linn Park extracted from ‘Coal from Clarkston to Cathcart’ (1999) by Stuart Nisbet. This has much more detailed information than my amateur efforts.
“There are five main coal seams below the Index Limestone, their local names being the Sclutty, Smithy, Main, Jewel and Geordies coals: the ‘Cathcart Coals’. These local coals were exploited from an early date from outcrops in the river valley. Unlike areas of deep mining, Linn Park still has evidence of exposures and old workings. This is why the area remains so interesting today. The thickness of the Cathcart Coals varies considerably, but the variety of seams meant that there were usually several of workable thickness at any location.”
Coal was distilled in an industrial scale in Glasgow for gas making at very high temperatures to create permanent gas and as little liquid as possible.
Shale on the other hand was distilled at a low temperature to obtain liquid and solid products and a little quantity of gas. This could be achieved with small scale plant such as a Kirk's Vertical Retort.
The steam injection pipe at the base of the Vertical Retort (which would serve no purpose in a pipe bridge!) allowed for the diffusion of heat and the more efficient recovery of the vapours at a more even temperature.
The oil vapours were collected and cooled to condense in the vessel connected to the iron column and provide the raw material for fractional distillation of other products.
In the mid-1800's, aniline dyes were first created by destructive distillation and treatment of the residues with various chemicals.
At first they were very expensive but industrial processes soon made them economic to use.