Industrial indicators of salt mines
(1) According to the “Specifications for Geological Exploration of Salt Lake Mineral Deposits†(Trial), the general industrial indicators of the Shiyan Salt Lake deposits provided in 1993 are shown in Table 1. Examples of mineral industry indicators: Jilantai Lake Salt Mine, Inner Mongolia 1) Solid phase rock salt: cut-off grade NaCl > 35%, industrial grade NaCl > 65%; CaSO 4 is not controlled by indicators, but the content is 5% alone; The thickness is not less than 0.5 m (from the stripping of the halogen cover). According to the "Mineral Industry Requirements Reference Manual" edited by the National Mineral Reserves Committee, the general industrial indicators for rock salt deposits in 1987 are: boundary grade NaCl ≥ 10% ~ 15%; industrial grade NaCl ≥ 20% ~ 30%; ore grade NaCl: Grade I products are ≥86%, Grade II products are 61% to 85%, Grade III products are 30% to 60%, and pit mining methods are available for thicknesses of 0.3 m. Reflex sights, also known as red dot sights, are a type of non-magnifying gun sight used on firearms to improve target acquisition and accuracy. They work by projecting an illuminated aiming point, such as a red dot or a green dot, onto a lens that the shooter looks through. This dot is aligned with the firearm's barrel, allowing the shooter to quickly and accurately aim at the target. Red Dot Sights,Tactical Shooting Accessories Guangzhou Miaozhun Jie Trade Co.,Ltd. , http://www.focuhunter.shop
See Table 2 for the technical and feasible comprehensive evaluation indicators of the companion (co-) component of the salt lake minerals.
2) Intercrystalline brine and confined brine: The exploration engineering control boundary is the ore range, and the concentration is above 20°Be/15°C (relative density is 1.161), which is converted into off-balance sheet reserves.
3) Glauber's salt (below the solid phase salt layer): the content of Na 2 SO 4 content greater than 30% is the off-balance sheet reserve.
(2) According to the National Mineral Reserves Administration “Guidelines for Geological Exploration of Salt Deposits†(Draft for Comment), the industrial indicators of rock salt and underground brine deposits (Table 3) provided in 1988 are as follows:
Example of mineral industry index: Hubei Yunying Salt Mine The mine is produced by water-soluble method. The industrial indicators are:
(1) Rock salt quality requirements The thickness of the salt layer unit layer is ≥0.1 m, the boundary grade is NaCl≥35%; the salt group (mineral body) cumulative pure salt thickness is ≥1.5 m; the salt group ore concentration is ≥40%;
Harmful impurity content (water soluble): Pb < 0.0001%, Ba < 0.002%, Mg < 0.5%, and As, F and Zn are <0.0005%.
(2) Mining technical conditions Mining height: no more than 25 m; maximum stone thickness: hard rock ≤ 1.5 m; mudstone or calcium thenardite ≤ 2 m; minimum mining depth: 200 ~ 270 m.
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