The mining method is selected and divided into three steps: scheme primary selection, mining method technology comparison and mining method economic comparison according to the general method. 1. Before the preliminary selection of the scheme, the rock mass mechanics data collected from the geological report and the survey site should be used to estimate the stability of the rock, the allowable volume of the mining stope, and the maximum span of the exposed roof. The mining block ranges by selecting different mining methods or stope components, and then analyzing the veto conditions (ie, determining the idleness) and control conditions of the mining method selection, and several feasible solutions are preferred. The choice of this step is related to whether all good programs can be selected, so it must be done on a case-by-case basis. For the selection of representative programs, draw a standard map of the mining method plan and select relevant technical and economic indicators. 2. Mining method technology comparison The selection of the primary selection should not exceed 3~5, and 2~3 is better. Compare the following contents one by one for these programs; (1) production capacity of the ore block; (2) ore depletion rate; (3) Ore loss rate; (4) Thousand tons of ore mining ratio; (5) Labor productivity of the nuggets; (6) Consumption of main materials, especially wood, steel, and cement; (7) The complexity of the mining process and the difficulty of production management; (8) Safety of working place, good or bad ventilation conditions, etc. Technology is relatively similar conditions can refer to the actual index mines, fixed or expanding indicators (containing about 5 to 10% error), or the actual data analysis proposed techniques. In the analysis, it is inevitable that there will be advantages and disadvantages in the same scheme. In this case, it is necessary to distinguish the primary and secondary, and focus on the factors that play a leading role under specific conditions. For example, precious and rare metals ore loss and dilution rate deposit rate is the dominant factor; ore for low-cost, labor productivity and production capacity Nuggets became the dominant factor. In general, after a technical comparison, a reasonable mining method can be selected. The real strengths and weaknesses cannot be determined by a few. In this case, select 2 to 3 competitive methods with different types of mining methods to carry out the third step of technical and economic comprehensive comparison. 3. Mining method Economics The essence of comparative economic comparison is also a comprehensive analysis and comparison. It is based on comparative economic effects and involves the difference between each specific indicator after each program is realized. The economic comparison requires detailed technical and economic calculations, based on the calculation results, for the final analysis and assessment. The comprehensive analysis and comparison includes the following three aspects : (1) Indicators for characterizing economic effects: mining ore cost, final product cost, annual profit, total profit or its net present value; infrastructure annual investment, investment return rate, return period, etc.; (2) The quantity and quality of the annual production of useful ingredients in the scale of the ore, or the total number of years of service; (3) Main technical indicators : mining capacity, thousand tons of ore mining ratio, labor conditions and productivity, consumption of bulk materials such as cement and pit wood. For comprehensive analysis and comparison, when the mining capacity and depletion loss rate indicators of the various mining method schemes that are involved in the comparison are different (influencing the determined scale and the quantity and quality of the products per year), a comprehensive comprehensive comparison is required. In both cases, only a simplified comparison can be made. (1) When the mining method of the comparative mining method has a large difference in depletion and loss rate, and all the mining ore, quantity, and mining-related investment are not much different, and the scale is the same, only the two programs are compared. Profit, the difference in total profit' (2) When the mining method involved in the comparison is depleted, the loss rate, the production capacity of the ore, and the investment related to mining are basically equal, it is only necessary to compare the cost of mining ore. The following is a brief description of the calculation method for mining ore cost and product profitability indicators. (1) The cost of ore is mined. The cost of producing ore is a comprehensive economic indicator for mining plants in independent mines or mining joint ventures. Generally, it can be selected according to the actual cost index of the mining enterprise with similar conditions. When there is no actual cost indicator available for utilization, it can be calculated according to the designed technical and economic indicators and quota. In the design of mining enterprises, the ore cost is often calculated according to the cost and cost project. For the extra-large mines, the operating cost can also be calculated according to the production process. Cost-based items include: 1) Auxiliary material costs. Refers to the explosives, detonators, fuses, detonating wires, brazing steel, alloy bit, pit wood, tires, wind pipes and other materials consumed in the production process of the mine. Calculate by multiplying the local material price by the design consumption quota, or by the nationally prescribed price (considering the miscellaneous charges) multiplied by the design consumption quota. 2) The process consumes fuel and power. It refers to the cost of gasoline, diesel, coal , electricity and wind power consumed in the production of mines (excluding the consumption of repair facilities). The fuel cost is multiplied by the unit price of the design, and the electricity fee in the power fee is charged according to the current two national electricity prices. 3) Production workers' wages and surcharges. The wages of production workers refer to the sum of the basic and auxiliary wages of direct production workers and auxiliary production workers (excluding mechanics, maintenance and non-production personnel) engaged in mine production. Auxiliary wages refer to floating wages and various wage allowances, which can be obtained by taking the auxiliary wage factor by the basic salary. The average salary level of underground mine workers is 4~5, and the auxiliary wage coefficient is 0.25~0.30. The wage surcharge refers to labor insurance , medical expenses and welfare fees , which are contributed by 11% of the total wages of the production workers. 4) Depreciation. Investment in well engineering, construction (construction), mining engineering equipment, etc. is a fixed asset investment. Basic depreciation refers to the basic depreciation charge drawn from the fixed asset investment, based on the basic depreciation rate determined by the service (use) years. 5 ) Overhaul and maintenance costs. The overhaul fee is planned to repair the project, and the maintenance fee refers to the small repair cost of the fixed assets. Overhaul fees are drawn from fixed asset investments at major repair rates. The overhaul rates for black underground mines and colored underground mines are both 1 to 1.5), while the overhaul rates for non-ferrous mining equipment are 2.0). The maintenance fee is based on the maintenance rate, and the maintenance rate for underground mine equipment and buildings is 12). 6) Workshop expenses and business management fees. Workshop expenses and enterprise management fees refer to various management fees and business expenses paid within the scope of the workshop and enterprise. It includes a wide range of cost items and complex calculations. Generally, newly designed mines are often selected according to similar mines, and the mines are expanded and expanded according to actual indicators. The operating cost is calculated according to the production process, and the cost items include: mining, mining, lifting, transportation, ventilation, drainage, crushing, maintenance or depreciation, and enterprise management fees. The cost of ore is recovered from the total cost of each operation. According to this calculation method, the economic effects of each production link can be analyzed. (2) Product profit indicators. Product profitability refers to the difference between the national price and product cost of the product. It is a comprehensive economic indicator that comprehensively measures the quality of work in all aspects of the enterprise, and is also an important value indicator for evaluating the design technical plan. There are three ways to express profit indicators: 1) Profit per unit of product. When only one product, such as ore, concentrate or metal, is extracted from the ore, the unit product profit is calculated as the difference between the unit product price and its cost. 2) One ton of mined ore is profitable. When extracting several products from the ore, because the quantity and profit of each product are different, it is necessary to calculate the industrial value of one ton of ore and the recovery of one ton of ore. The difference between transportation and processing costs is one ton. The industrial utilization profit of mining ore, ie 3) Profit from mining. When comparing the number of products produced by the two design schemes, considering the recovery index of the entire deposit in the mining and processing process, it is necessary to use the mining profit index to compare the profit of the scheme. The profit index of mining exploitation can be calculated by the following formula: D—profit of unit product, yuan/t; also differentiated by different products; G—The quantity of products obtained by mining (the amount of ore produced, the amount of concentrate, the amount of metal), t. The annual profit of the comparative design is derived from the difference between the annual gross output value of the enterprise and the total annual cost of the enterprise, or from the profit per unit of product multiplied by the annual production. Chaff Cutter,Chaff Cutter Machine,Electric Chaff Cutter Machine,Electric Chaff Cutter Shuangfeng Nongjiabao Machinery Technology Co., Ltd , https://www.starchmachine.nl
In the formula D - the profit of mining mining, yuan; depending on the output of the product, the ore, concentrate or metal can be mined;