How to properly understand the specifications in mining

With the technical level and increasingly modern machinery and equipment, the mass acceptance in mining is increasingly meticulous and accurate. On the other hand, the methods of calculating mine volume are always approved by ministries and sectors according to carefully tested standards. However, at present, due to lack of access to all information, not everyone understands the technical parameters of mining correctly.

This is also understandable, because for each of the specifications in the standards are specified and it can also be classified into many parameters under different conditions. This alone, the "inside" technicians had to work hard to apply to direct and operate, and at the same time as a basis for reporting. Therefore, it is normal for "outside" people to not fully understand. For example, in TCVN 5326:2008 compiled by the Vietnam Coal-Mineral Industry Group, appraised and approved by the Ministry of Industry and Trade, the Ministry of Science and Technology publishes open-pit mining techniques, in Section 2.16 stipulates The stripping ratio has clearly defined the concept: “The stripping coefficient is the ratio between the volume of soil and rock to be removed and the corresponding amount of minerals that can be extracted. Peeling coefficient can be calculated in units, m3/ton, m3/m3 or ton/ton”.

From this concept, technicians deploy in production practice through many different calculation methods. For units of m3, the calculation is based on geodetic blocks, or m3 of loose expansion. Geodetic cubic meter, i.e. unexploded monolithic soil measured by geodetic method. The bulk meter is the cubic meter after blasting. The coefficient of loose expansion of soil and rock depends on the physical and mechanical properties of each type of rock under different conditions. According to TCVN5326:2008, soft rock soil has a coefficient of loose expansion from 1.02 to 1.15; medium solid rock with coefficient of bulk expansion from 1.15 to 1.45; and very solid rock has a coefficient of loose expansion from 1.45 to 1.60. That is, one cubic meter of geodesic soil can be equal to 1.6 cubic meters of loose rock. Thus, based on the fact, each mine can apply different coefficient of bulk expansion due to different physical and mechanical properties of soil and rock.

For the calculation in tons, one will have to base on the density of each different type of rock or coal. As for Coal, currently, the mines have applied large tonnage electronic scales to accurately calculate each weight. However, in addition to balancing the type of electronic balance, the calculation of the mass also requires more detailed calculations related to the moisture index of coal. The moisture content of coal is sampled and analyzed daily, especially before weighing. The greater the moisture content, the higher the coal weight. Therefore, the exact weight will be subtracted when the humidity is high…

In addition, the coefficient of rock removal is also classified according to each nature and condition to calculate the appropriate efficiency for each period, time or mining location. For example: phasic stripping ratio: is the ratio between the total volume of soil and rock to be removed and the amount of minerals extracted from the mine in each specific period; Break-even stripping ratio (also known as break-even stripping ratio): is the maximum amount of rock and soil that must be removed to extract a unit of mineral volume at a cost equal to the cost of mining. allow; Limitary stripping ratio: is the ratio between the increment in the mass of stripped rock and the increment in the volume of the corresponding mineral that can be extracted when the mine's boundary is extended over a certain distance; Timely stripping ratio: is the ratio between the increment in the mass of peeled soil and the increment in the corresponding mineral volume exploited when developing the working bank in a certain time or space; Production stripping ratio: is the ratio between the volume of soil and rock to be peeled and the amount of minerals exploited in a certain production period… The overall mining efficiency of the mine will be calculated by the system. average number of peels. Average stripping ratio: is the ratio between the volume of soil and rock to be removed and the amount of minerals extracted in the entire boundary of the mine.

For underground mining, today's modern machinery and equipment for geodesy and geology also allow to measure cubic meters of coal right at the underground seams. The calculation coefficients are similar and detailed according to approved standards such as: Coefficient of meters for the furnace to be prepared for production; basic construction furnace meter coefficient; consumption of materials, motivation, raw materials, fuel... for each ton of coal mined...

As you can see, mining, whether it's open-pit mining or underground mining, has complicated specifications because coal or rock is underground. The applied technical parameters are mainly synthesized from the practice of each region. The specifications of one region cannot be applied to another region or one country to another. Based on reality, every year, ministries and agencies have consensus and appropriate adjustments. Units in the Group also strictly follow decisions, circulars, directives... under the supervision of competent authorities to calculate and apply efficiency in production and business of each unit. . During the implementation process, all levels and sectors also regularly exchange information, organize seminars and discuss to come up with the most appropriate technical parameters according to each position and period...