Lime burning from earliest times: Great Rocks Dale
Romans and medieval castle and church builders used lime for mortar and plaster in building. Fitzherbert of Tissington (1525) was probably the first Englishman to write about the use of lime in agriculture. This area has been probably Britain's most important lime producing area since at least 1650, when a survey referred to fourteen kilns.
The process of heating limestone, producing lime and carbon dioxide, has remained unchanged, but methods now are completely different. Originally, when temporary timber-fired, earth-covered ‘kilns' had burnt through, the structure would be taken apart and the lime removed. These were replaced by stone kilns, which, unlike the older ‘intermittent' kilns, could be operated continuously.
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From 1700, local coal and limestone were fed into the top of the kiln and lime extracted from the bottom. Lime (with salt) became a vital raw material for the Cheshire chemical and Lancashire textile industries. The Peak Forest Canal (opened 1797), made Dove Holes the most accessible source. By 1900, metal kilns, lined with refractory bricks, were taking over. Modern gas-fired kilns operate at about 900ºC. Lime from quarries such as Tunstead in Great Rocks Dale (along with salt from beneath the Cheshire Plain) is still used in the manufacture of ‘soda ash' (sodium carbonate). This ‘heavy' chemical is produced at Northwich in Cheshire and is a vital ingredient in everyday products such as glass, soap and detergents. Lime from the Buxton area accounts for about half the national output and is also used for many other purposes including steel manufacture, water purification and sewage treatment. |
