Physical Properties and Uses of Marble
Marble occurs in large deposits that can be hundreds of feet thick and geographically extensive. This allows it to be economically mined on a large scale, with some mines and quarries producing millions of tons per year.
The use of explosives in the quarrying of marble is limited because of the danger of shattering the rock. Instead, channeling machines that utilize chisel-edged steel bars make cuts about 5 cm (2 inches) wide and a few metres deep. Wherever possible, advantage is taken of natural joints already present in the rock, and cuts are made in the direction of easiest splitting, which is a consequence of the parallel elongation of platy or fibrous minerals. The marble blocks outlined by joints and cuts are separated by driving wedges into drill holes. Mill sawing into slabs is done with sets of parallel iron blades that move back and forth and are fed by sand and water. The marble may be machined with lathes and carborundum wheels and is then polished with increasingly finer grades of abrasive.
Total world quarrying production in 2019 was approximately 316 million tonnes; however, quarrying waste accounted for 53% of this total production. In the process of marble mining and processing, there will be a large amount of non-degradable waste, which will cause serious damage to the environment and threaten the life of animals and plants For example, the poor management of mining activities has resulted in a large amount of waste rocks, and the waste is thrown by the river, polluting the surrounding water sources, causing groundwater pollution, and endangering human health. According to the research of water samples around the marble mine, it was found that the number of cations and anions in the water increased.
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