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Zhang Z.G.,Hebei Polytechnic University | Zhang Z.G.,Wuhan University | Zhang Z.G.,Key Laboratory Mineral Development and Security Technology of Hebei Province | Gao L.F.,Hebei Polytechnic University | And 9 more authors.
Advanced Materials Research | Year: 2011

Gas hydrate is a new energy in the 21st century with the characteristics of high energy density, huge amount of resources and cleaning. It has important significances for resources development, environmental protection and global climate changing. Due to the limitations of the occurrence mode and the technical level of marine gas hydrates, at present, the development and utilization of the resources are still tentative. This article analyzed and evaluated several key technologies to develop marine gas hydrates, that is depressurization, thermal methods, chemical injection method, CO2 replacement method, and fluorine gas+microwave method. However, these methods are difficult to control in the mining process. The research based on the properties of the occurrence of marine gas hydrate, used the principle of gas hydrate decomposition caused by vibration, by adjusting the excitation intensity, frequency, and amplitude. Different local oscillator strength applied on the Occurrence of gas hydrate layer. Gas hydrate stable state changed in mining region, prompting the gas hydrate conversing from solid to gas. Numerical simulations show: Low-frequency vibration should be used in the layers with higher hydrate saturation. The vibration frequency should be improved in the layers with lower hydrate saturation. The method has a good controllability for the region and the process of mining, avoiding geological disasters and environmental issues in the seabed caused by the mining process losing control. © (2011) Trans Tech Publications. Source


Gao L.F.,Hebei Polytechnic University | Gao L.F.,Key Laboratory Mineral Development and Security Technology of Hebei Province | Zhang Y.,Hebei Polytechnic University | Zhang Y.,Key Laboratory Mineral Development and Security Technology of Hebei Province | And 9 more authors.
Advanced Materials Research | Year: 2011

Pressure bump in coal mine production safety is a serious disaster. Geological conditions in Kailuan Mine are complex. Coal strata based on the Carboniferous - Permian coal. The roof and floor are made of sandstone and mudstone with poor rigidity. Fault development and mine have large amount of water inflow. Most of mine are already getting into the mining stage over one thousand meters deep. Increasing stress and high stress induced pressure bump as a key factor. In this paper, according to geological characteristics of Kailuan Coal, it analyzes the impact and the laws of pressure bump in the representation of deep mining phase, which have certain reference for coal mine safety production. © (2011) Trans Tech Publications. Source


Gao L.-F.,Hebei United University | Gao L.-F.,Taiyuan University of Technology | Gao L.-F.,Key Laboratory Mineral Development and Security Technology of Hebei Province | Zhang Y.,Hebei United University | And 6 more authors.
Procedia Environmental Sciences | Year: 2011

Coastal wetlands are important land resources in Tangshan, including natural wetlands and artificial wetlands. Spatial form of wetlands is zonal distribution, contours approximately paralleling with the coastlines. The formation is controlled by the favorable weather conditions and good hydrogeological conditions, such as the rapid subsidence of ground caused by Neotectonics, abundant precipitation system and dense surface water. The formation and development of coastal wetlands in Tangshan is the response record to research coupling relationship among neotectonic movement - climate evolution - environmental changes. © 2011 Published by Elsevier Ltd. Source


Zhang Y.,Hebei Polytechnic University | Zhang Y.,Key Laboratory Mineral Development and Security Technology of Hebei Province | Gao L.F.,Hebei Polytechnic University | Gao L.F.,Key Laboratory Mineral Development and Security Technology of Hebei Province | And 6 more authors.
Advanced Materials Research | Year: 2011

Pressure bump is a serious disaster to threat coal mine production safety. The roof and floor strata in Kailuan coal mine are made of sandstone and mudstone with relatively poor rigidity. Most of mines have been into the deep mining stage over one thousand meters. High-stress becomes the key factor induced pressure bump. In this paper, according to coal mining strata, fault development, mine inflow and other geological factors, based on fracturing parameters of mine rock and wall rock in the pilot mines (Qianjiaying Mine, Tangshan Coal Mine), boundary conditions of the occurrence of pressure bump is tested by numerical simulation using RFPA software. It discusses the mechanism and laws of pressure bump under high stress in the deep mining. Mining face and roadway are taken real-time monitoring, using micro seismic monitoring system (MMS). The location and level of micro seismic events within the coal formation caused by breakdown could achieve precise position. Spatial distribution and characteristics of coal and rock bursting could be identified. The stability of coal and rock could be monitored real-time and analyzed. Pressure bump could be predicted and prevented effectively. © (2011) Trans Tech Publications. Source


Zhang Z.,Wuhan University | Zhang Z.,Hebei United University | Zhang Z.,Key Laboratory Mineral Development and Security Technology of Hebei Province | Du Y.,Wuhan University | And 12 more authors.
Journal of Rare Earths | Year: 2012

Polymetallic nodules and crusts are two of the most important mineral deposits in the ocean. They are rich in rare earth elements (REEs), iron, manganese, copper, cobalt, nickel, and other useful metals. This paper discussed the analysis of 25 nodule and crust samples collected from the South China Sea, the Pacific, Atlantic, and Indian Oceans. The samples were analyzed for REE content by ICP-MS/AES. The average REE concentration was found to be 1096.96×10 -6 in the nodules and 1623.88×10 -6 in the crusts. Both of these values are much higher than those recorded in Earth's dry-land crust and sedimentary rocks. This REE enrichment is mainly controlled by the absorption of ferromanganese oxides and clay minerals in the nodules and crusts and the high levels of REEs in seawater and sediments. High cerium enrichment in the nodules and crusts may lead to more effective exploitation of REEs in the future. © 2012 The Chinese Society of Rare Earths. Source

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