In Kaiyang Phosphorus Mine, serious environmental and safety problems are caused by large scale mining activities in the past 40 years. These problems include mining subsidence, low recovery ratio, too much dead ore i...In Kaiyang Phosphorus Mine, serious environmental and safety problems are caused by large scale mining activities in the past 40 years. These problems include mining subsidence, low recovery ratio, too much dead ore in pillars, and pollution of phosphorus gypsum. Mining subsidence falls into four categories: curved ground and mesa, ground cracks and collapse hole, spalling and eboulement, slope slide and creeping. Measures to treat the mining subsidence were put forward: finding out and managing abandoned stopes, optimizing mining method (cut and fill mining method), selecting proper backfilling materials (phosphogypsum mixtures), avoiding disorder mining operation, and treating highway slopes. These investigations and engineering treatment methods are believed to be able to contribute to the safety extraction of ore and sustainable development in Kaiyang Phosphorus Mine.展开更多
From Nov 15 to 17,the 4th Nishan Forum on World Civilization(Nishan Forum)was held in Qufu city(the birth place of Confucius),Shandong Province.Xu Jialu,Vice-Chairman of the 9th and 10th NPC Standing Committee deliver...From Nov 15 to 17,the 4th Nishan Forum on World Civilization(Nishan Forum)was held in Qufu city(the birth place of Confucius),Shandong Province.Xu Jialu,Vice-Chairman of the 9th and 10th NPC Standing Committee delivered a speech at the opening ceremony.More than 200representatives(including about 40 foreigners)including politicians,experts and members展开更多
Ground crack and subsidence were investigated in Kaiyang Phosphorus Mine as an example. Contribution factors to cause ground crack and mining subsidence were studied, including mining method, mining depth and ore thic...Ground crack and subsidence were investigated in Kaiyang Phosphorus Mine as an example. Contribution factors to cause ground crack and mining subsidence were studied, including mining method, mining depth and ore thickness and stope size, dip angle of orebody, geological structure, nature of overburden and water contents, and roof supports, etc. Countermeasures against cracks and subsidence were put forward. The uniaxial compressive strength of compounded phosphorus gypsum after 28 d of curing period was tested to be more than 1 MPa. Phosphorus gypsum can be used as materials for the backfill of stope. By comparison and numerical simulation, cut and fill mining method with middle-deep drilling holes and ore transportation by blasting force was selected as the optimum mining method in Kaiyang Phosphorus Mine.展开更多
Selenium is one of the life-related elements. Survey reveals that selenium enrichment in the studied strata from Kaiyang County is considered to be closely related to the following factors: regional black shale series...Selenium is one of the life-related elements. Survey reveals that selenium enrichment in the studied strata from Kaiyang County is considered to be closely related to the following factors: regional black shale series in Niutitang Formation of Early Cambrian, strong adsorption of organic matter(OM), magmatic hydrothermal migrate along the deep fault, mixing and migration of hydrothermal brine, regional uranium mineralization and presence of a great deal sulfides. For selenium enrichment in its weathered soil and crops, the reason responsible is selenium-enriched bedrock, which provides material sources for weathering profile and is considered as the main controlling factor of selenium content in the soil profile. After leaching and migrates downwards, organic carbon(OC) adsorption, iron-manganese layer adsorption, geochemical barrier role, selenium content in different profiles, there are mainly three types of distribution features: bottom enrichment type, top enrichment type and no significant enrichment type. Comprehensive analyses find that selenium enrichment area is mainly distributed in the Machang, Gaoyun-Fengsan-Guanpo, Baimadong, Chuandong-Hefeng-Shaoshang and Longgang-Gaozhai region, etc. Besides, around the east part of the county, in Huali and Yongxing selenium are relatively scarce.展开更多
基金Projects(50404010 50574098) supported by the National Natural Science Foundation of ChinaProjects (05JJ10010) supported by the Hunan Provincial Natural Science Foundation of Distinguished Young Scholars
文摘In Kaiyang Phosphorus Mine, serious environmental and safety problems are caused by large scale mining activities in the past 40 years. These problems include mining subsidence, low recovery ratio, too much dead ore in pillars, and pollution of phosphorus gypsum. Mining subsidence falls into four categories: curved ground and mesa, ground cracks and collapse hole, spalling and eboulement, slope slide and creeping. Measures to treat the mining subsidence were put forward: finding out and managing abandoned stopes, optimizing mining method (cut and fill mining method), selecting proper backfilling materials (phosphogypsum mixtures), avoiding disorder mining operation, and treating highway slopes. These investigations and engineering treatment methods are believed to be able to contribute to the safety extraction of ore and sustainable development in Kaiyang Phosphorus Mine.
文摘From Nov 15 to 17,the 4th Nishan Forum on World Civilization(Nishan Forum)was held in Qufu city(the birth place of Confucius),Shandong Province.Xu Jialu,Vice-Chairman of the 9th and 10th NPC Standing Committee delivered a speech at the opening ceremony.More than 200representatives(including about 40 foreigners)including politicians,experts and members
基金Projects(50574098, 50404010) supported by the National Natural Science Foundation of China project(05jj10010) supported by the Hunan Provincial Natural Science Foundation of Distinguished Young Scholars
文摘Ground crack and subsidence were investigated in Kaiyang Phosphorus Mine as an example. Contribution factors to cause ground crack and mining subsidence were studied, including mining method, mining depth and ore thickness and stope size, dip angle of orebody, geological structure, nature of overburden and water contents, and roof supports, etc. Countermeasures against cracks and subsidence were put forward. The uniaxial compressive strength of compounded phosphorus gypsum after 28 d of curing period was tested to be more than 1 MPa. Phosphorus gypsum can be used as materials for the backfill of stope. By comparison and numerical simulation, cut and fill mining method with middle-deep drilling holes and ore transportation by blasting force was selected as the optimum mining method in Kaiyang Phosphorus Mine.
基金financially supported by the 211 National Key Program of Discipline Construction,Guizhou University,China(No.KST-200903)
文摘Selenium is one of the life-related elements. Survey reveals that selenium enrichment in the studied strata from Kaiyang County is considered to be closely related to the following factors: regional black shale series in Niutitang Formation of Early Cambrian, strong adsorption of organic matter(OM), magmatic hydrothermal migrate along the deep fault, mixing and migration of hydrothermal brine, regional uranium mineralization and presence of a great deal sulfides. For selenium enrichment in its weathered soil and crops, the reason responsible is selenium-enriched bedrock, which provides material sources for weathering profile and is considered as the main controlling factor of selenium content in the soil profile. After leaching and migrates downwards, organic carbon(OC) adsorption, iron-manganese layer adsorption, geochemical barrier role, selenium content in different profiles, there are mainly three types of distribution features: bottom enrichment type, top enrichment type and no significant enrichment type. Comprehensive analyses find that selenium enrichment area is mainly distributed in the Machang, Gaoyun-Fengsan-Guanpo, Baimadong, Chuandong-Hefeng-Shaoshang and Longgang-Gaozhai region, etc. Besides, around the east part of the county, in Huali and Yongxing selenium are relatively scarce.
