The scalloped medium-length hole blasting mining method used in Dahongshan Copper Mine accounted for more than 61%of the total amount of mining,but the large boulder yield restricted the intensity of ore supply for mi...The scalloped medium-length hole blasting mining method used in Dahongshan Copper Mine accounted for more than 61%of the total amount of mining,but the large boulder yield restricted the intensity of ore supply for mines,and the average boulder yield was as high as 22.7%.In order to develop the mine production efficiency,the circular medium-length hole blasting technology was proposed and field tests were carried out.The test results showed that circular medium-length hole blasting mining can reduce the average boulder yield to 10.3%.Compared with the traditional scalloped medium-length hole blasting mining,the average boulder yield was decreased by 12.4%.The daily yield of ore for the panel on duty was increased by 152.29 t,and the growth rate was 51.1%.The new technology can reduce the time for the handling of boulder and the consumption of explosives and detonators for recrushing,and increase the efficiency of mining while reduce the mining cost,which has received good blasting effects.展开更多
Xinji No. 2 underground coal mine extracts the coal seams #4 and #5. These two seams are highly gassy and gas drainage is required to control mine gas emission and reduce outburst risk. Because the seam permeability c...Xinji No. 2 underground coal mine extracts the coal seams #4 and #5. These two seams are highly gassy and gas drainage is required to control mine gas emission and reduce outburst risk. Because the seam permeability coefficient is very low and around 0.1 m^2/(MPa^2·d), a number of technologies have been trialled to enhance the seam permeability prior to gas drainage. Of these technologies trialled, the deep borehole presplitting blasting technology has been proven to be quite effective in increasing permeability. In Xinji No. 2 mine it doubled or sometimes tripled gas drainage volume. This paper describes the technology, its application in the enhancement of seam permeability in Xinji No. 2 coal mine, and its effect on gas drainage performance.展开更多
For transportation of solid backfill material such as waste and fly ash from the surface to the bottom of the shaft in a fully mechanized backfilling coal backfilling coal mining technology, we developed a new vertica...For transportation of solid backfill material such as waste and fly ash from the surface to the bottom of the shaft in a fully mechanized backfilling coal backfilling coal mining technology, we developed a new vertical transportation system to transport this type of solid backfill material. Given the demands imposed on safely in feeding this material, we also investigated the structure and basic parameter of this system. For a mine in the Xingtai mining area the results show that: (1) a vertical transportation system should include three main parts, i.e., a feeding borehole, a maintenance chamber and a storage silo; (2) we determined that 486 mm is a suitable diameter for bore holes, the diameter of the storage silo is 6 m and its height 30 m in this vertical transportation system; (3) a conical buffer was developed to absorb the impact during the feeding process. To ensure normal implementation of fully mechanized backfilling coal mining technology and the safety of underground personnel, we propose a series of security technologies for anti-blockage, storage silo cleaning, high pressure air release and aspiration. This vertical transporting system has been applied in one this particular mine, which has fed about 4 million tons solid material with a feeding depth of 350 m and safely exploited 3 million tons of coal.展开更多
基金National Natural Science Foundation of China （No. 51304087） Foundation Projects of Yun- nan Province （No. KKSY201404056, No. KKSA201121083）
文摘The scalloped medium-length hole blasting mining method used in Dahongshan Copper Mine accounted for more than 61%of the total amount of mining,but the large boulder yield restricted the intensity of ore supply for mines,and the average boulder yield was as high as 22.7%.In order to develop the mine production efficiency,the circular medium-length hole blasting technology was proposed and field tests were carried out.The test results showed that circular medium-length hole blasting mining can reduce the average boulder yield to 10.3%.Compared with the traditional scalloped medium-length hole blasting mining,the average boulder yield was decreased by 12.4%.The daily yield of ore for the panel on duty was increased by 152.29 t,and the growth rate was 51.1%.The new technology can reduce the time for the handling of boulder and the consumption of explosives and detonators for recrushing,and increase the efficiency of mining while reduce the mining cost,which has received good blasting effects.
文摘Xinji No. 2 underground coal mine extracts the coal seams #4 and #5. These two seams are highly gassy and gas drainage is required to control mine gas emission and reduce outburst risk. Because the seam permeability coefficient is very low and around 0.1 m^2/(MPa^2·d), a number of technologies have been trialled to enhance the seam permeability prior to gas drainage. Of these technologies trialled, the deep borehole presplitting blasting technology has been proven to be quite effective in increasing permeability. In Xinji No. 2 mine it doubled or sometimes tripled gas drainage volume. This paper describes the technology, its application in the enhancement of seam permeability in Xinji No. 2 coal mine, and its effect on gas drainage performance.
基金support for this work provided by the National Natural Science Foundation of China (No. 51074165)the major program of the National Natural Science Foundation of China (No. 50834004)the Innovation Project of Graduate Students of Jiangsu Province (No. CXZZ11-0308)
文摘For transportation of solid backfill material such as waste and fly ash from the surface to the bottom of the shaft in a fully mechanized backfilling coal backfilling coal mining technology, we developed a new vertical transportation system to transport this type of solid backfill material. Given the demands imposed on safely in feeding this material, we also investigated the structure and basic parameter of this system. For a mine in the Xingtai mining area the results show that: (1) a vertical transportation system should include three main parts, i.e., a feeding borehole, a maintenance chamber and a storage silo; (2) we determined that 486 mm is a suitable diameter for bore holes, the diameter of the storage silo is 6 m and its height 30 m in this vertical transportation system; (3) a conical buffer was developed to absorb the impact during the feeding process. To ensure normal implementation of fully mechanized backfilling coal mining technology and the safety of underground personnel, we propose a series of security technologies for anti-blockage, storage silo cleaning, high pressure air release and aspiration. This vertical transporting system has been applied in one this particular mine, which has fed about 4 million tons solid material with a feeding depth of 350 m and safely exploited 3 million tons of coal.
