Samples of the different distillates and products that are produced during the processing of Scottish oil-shale. Samples on the left contain distillates that are intermediary stages in the process such as the crude oil, crude distillate (green oil), blue oil. Samples on the right are the final products that are marketed for a range of uses e.g. motor spirit, lighthouse oil, cleaning spirit.
Top row, left to right: Crude Shale Oil, Crude Distillate, Blue Oil, Heavy Oil and Paraffin, Crude Naptha, Crude Burning Oil.
Bottom row, left to right: Crude Scrubber Naptha, Sulphate of Ammonia, Ammoniacal Liquor, Motor Spirit, Lighthouse Oil, Power Oil, Cleaning Spirit.
Diagram illustrating processes of manufacture in the Scottish oil-shale industry.
The diagram shows the complete process from the original shale through the various treatments and distillations and showing the end products. The process can be conveniently considered in two stages. The raw oil-shale is distilled/heated in retorts in the absence of air and in the presence of steam. This allows the shale to undergo decomposition and distillation into crude oil and ammonia. The second stage is refining the crude oil. The object is to obtain from the crude oil various types of refined oil and wax as required by the prevailing markets at the lowest possible working cost and with the smallest amount of capital spent on refining plant.
Other samples from the Scottish Shale oil industry
Bob McIntosh
From oil-shale to candle, from the raw material, intermediate distillates to final product. Examples from the early Scottish oil-shale industry.
The shale oil industry started in Scotland in the 1850s reaching a peak in 1912 when 12,000 people worked in the industry. With the onset of the First World War and the importation of cheap oil from British interests in the Persian Gulf the industry saw rapid decline.
The image shows the steps from raw oil-shale fresh from the mine to a finished product - a packet of candles made from paraffin wax. The samples were sourced from the Pumpherston Oil Company Limited at Mid-Calder, a leading manufacturer in the Scottish shale oil industry.
Raw, black oil-shale (top left) was crushed and heated in a retort with injected steam to produce crude oil, this undergoes the first distillation to produce crude distillate (green oil). Top right, the spent oil shale. A second distillation of the green oil produced heavy oil containing paraffin. This was then separated into blue oil and crude solid paraffin. The latter paraffin wax in its unfinished state was refined and then manufactured into candles.
A full set of samples from each step in the process and the final products are held in the BGS collections in Edinburgh.
Bob McIntosh
D'Arcy, 4.0 km. south-east of Dalkeith and 1.6 km. south-south-west of the mining village of Chesterhill, Midlothian. Site of borehole, 1919-1922.
The boring commenced on the Carboniferous Lower Limestone Group which rises as a clearly defined anticline and which was believed to be favourable to oil accumulation. The boring is situated on the crest of this anticline. The boring produced gas at 724 feet (mainly a mixture of methane and ethane). This was sealed off. At 1810 feet some good quality oil was struck in a sandstone; the bore was stopped at 1820 feet. General view of oil well drilling rig, showing derrick and pile or casing against wall in foreground. A length of casing is suspended in the derrick by the travelling block. Photographer: D. Tait. BGS old photograph number: C02882.
For a short account of other notable and interesting boreholes in the UK visit the Geoscience Data Blog.
Bob McIntosh
