Sichuan Well Salt is an ancient and unique salt industry. The Qing government changed the official control mode of Sichuan well salt industry in past dynasties, and "let the people freely dig", which enabled well salt production to develop and sell in the vast areas of southwest China to a certain extent. The unprecedented development of Sichuan well salt industry in Qing Dynasty largely depended on the continuous progress of salt-making technology. As for drilling tools, five kinds of drilling tools have been created: fishtail file, silver ingot file, God of Wealth file, single horseshoe file and double horseshoe file.
The sinking process has been finalized into six processes: opening the wellhead, lowering the stone circle, drilling a big hole, lowering the wood and bamboo (casing for protecting the shaft wall), drilling a small hole and fanning mud (removing the cuttings and mud in the document). In the early Qing Dynasty, small wells were dug and shallow brine was mined. During the Ganjia period, with the improvement of salt-making technology, the well depth of Furong Salt Field was generally up to 120 feet, and yellow brine in Jurassic strata was mined. During Daoxian period, many wells in Furong salt area were thousands of meters deep, close to Triassic horizon, and black brine and rock salt were mined.
The importance of salt
Salt can be used in agriculture. For example, adding salt to soil can improve the yield and quality of agricultural products. In addition, salt can also be used in animal food to promote growth and prevent diseases. Salt is widely used in curing, smoking, curing and other food processing, which can prolong the shelf life of food and improve the taste of food.
Salt is also widely used in industry, such as paper making, glass, detergents and chemicals. In addition, salt is also used to purify metals and make plastics. The importance of salt to human beings cannot be ignored. It plays a vital role in many fields, but it is also necessary to control the salt intake reasonably. Therefore, the World Health Organization recommends that adults should not consume more than 5 grams of sodium per day.
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