Mining (1)
     70% to 80% of kaolin produced in China is used in ceramics and refractory materials, most of which directly use raw ore and low-grade refractory materials. Suzhou Suzhou Kaolin Mine is a soft kaolin with high grade and can be directly used in industry. Its hand No. 1 mud is more than 10 times higher than the hand No. 4 mud . Therefore, it is required to protect high quality soil during mining and protect the purity of the original ore. In order to make it not to be crumb-like, in the past, many manual mining and mining were carried out on the mining face. Now the mining scale is large, but in order to connect with the hand-selected factory, it is still necessary to pay attention to the selection. Kaolin ore price difference is large, for example: Suzhou China kaolin ore price is 230 yuan / t, Fujian Longyan Kaolin ore price of 90 yuan / t, Wuxian Castle Nai ores price of 203 5 yuan / t, ore sale. The price affects the choice of mining methods and mining processes. Guangdong Maoming kaolin is a sandy kaolin, water and water transport, mainly produces paper-based coating grade kaolin, there is no problem of the sale of raw ore, and its low-grade products are used for ceramics and fillers. In recent years, calcined kaolin is very popular in domestic and foreign markets, general domestic coal-based hard rock kaolin (clay) obtained by deep processing, hard rock kaolin (clay) because it is common and associated coal which is mined by The mining situation of coal and its own occurrence are determined by the comprehensive utilization department of the Ministry of Coal. It has not been mined separately in China, and will not be mentioned below.  ( 1 ) Division of mining methods and mining scale      The mining methods of kaolin mines are open pit mining and underground mining. Weathered residual kaolin mines are open-pit mining, such as Maoming's sandy kaolin. Other hydrothermal alterations and sedimentary deposits are used for open pit mining and deep underground mining.      There are many mining sites using open pit mining, but most of them are small and medium-sized mines. The large ones include Fujian Longyan Kaolin Company, Guangdong Maoming Kaolin Company, and Guangdong Maoming Southern Kaolin Company. Open-pit mining has been used in the Yangxi mining area and the Yangdong mining area of ​​the former Suzhou China Kaolin Company. The scale of underground mining is: Jiangsu Yangxi shaft, Guanshan shaft, Baishanling mine in Yangdong and Qingshan white mud mine in Wuxian.      The division of mining scale uses two methods: one is based on the amount of ore; the other is based on the amount of concentrate, see table  ( two ) open Extension Transport lose      Haulage open-pit mining of kaolin ore is used more three kinds: one for narrow roads and rail iron forge, with 7t, or 10t, 14t or motor vehicle towing      The development of underground mining is divided according to the type of main roadway: First, the shaft is developed. For example, the Yangxi shaft of Suzhou China Kaolin Company is the lower shaft. The Guanshan mine under construction is the upper shaft; Wuxian Qingshanbai The deep mining of the mud mine is the use of the lower shaft. The second is the development of inclined wells. For example, the original Yangxi main inclined shaft project of Suzhou China Kaolin Company uses the inclined shaft of the chassis; the shallow mining of Qingshan Baimu Mine in Wu County also uses the inclined shaft of the chassis. The third is joint development. For example, the Yangshan Baishan Lingding, owned by Suzhou China Kaolin Company, is jointly developed by Pingyi - Blind Diagonal Well.      Underground mining main transportation roadway is usually set in the bottom plate, away from the ore body 20 ~  The kaolin mine in underground mining has great speciality. The ore solidity coefficient is f= 1 ～ 2 , soft and brittle, plasticity, plasticity index in natural state, water absorption and swelling after water contact. It also has water-tightness and is a typical plastic medium, which is a plastomer. Underground mining activities are basically carried out in the plastic zone and the plastic zone. The ground pressure characteristics of the roadway after excavation in the ore body.      1) The surrounding rock has a large amount of deformation and rheological properties. For example, the underground mine of Suzhou China Kaolin Company, the stope is supported by a partitioned wooden shed, the section      The inner roadway should be closed and supported. According to the elastoplastic theory, the pressure inside the plastic zone is equal to the top pressure. In this case, from the perspective of optimal force performance, circular support should be adopted. However, the actual measurement proves that the lateral pressure in the plastic medium is generally slightly less than the top pressure, and it is possible to design an elliptical or elliptical lane.      In the stratified roadway in the mining area, due to the particularly large pressure of the mining site, the application of a flexible circular stone support in the mine of Suzhou China Kaolin Company has been successful, and no mortar is needed for the stone support. 1 ~ Cistern Tank,Water Cistern,Water Reservoir Tank,Pvc Water Tank HEBEI DONGDING CHEMICAL TRADE CO.,LTD , https://www.hebeiopct.com
     2) In the deformation activity, it is accompanied by volume expansion due to the water absorption property of the kaolin. As its water content continues to increase, it also causes its physical state changes, from solid to semi-solid, and has been fragmented. Therefore, in addition to plasticity, it has the characteristics of "loose".
     3) Some kaolinite ore bodies contain montmorillonite, and montmorillonite is easy to swell after water absorption. In the deformation of kaolin, there is also the influence of smectite water swelling, and the content of montmorillonite should be emphasized.
     4) The influence of stope dynamic pressure on the lower mining lane can be ignored. The local action of dynamic pressure is often consumed by the deformation of kaolin without being transmitted.