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China is a big country of coal production, in the coal mining process, the great massive mine drainage has caused not only the waste of groundwater resource, but also environmental pollution. On the other hand, mining production and life supply water is very scarce. According to the mine water features, the majority of mine drainage water belonging to the mine water containing suspended, the mine water needs to do the necessary purification then can be used. What the purification mainly eliminates is the suspended. In this paper, the method of purification and the technological process about mine water are discussed. The main methods of handling are coagulation, sedimentation, filtration and disinfection. According to different characteristics of water quality, different ways of handling and technological processes have to be chosen. Finally, the purification and utilization of mine water are shown through practical examples, Pingdingshan Coal Group Company, Wannian Coal Mine of Fengfeng Group Limited Company and Tangshan Coal Mine of Kailuan Group Company, to have obvious social, economic and environmental benefits.

Based on predictions of the mine inflow of water and the complexity of influential factors, a method of BP neural network is put forward for mine inrush water prediction in this paper. We chose proper impact factors and establish non-linear artificial neural network prediction model after analyzed the impact factors of mine water inflow in Shandong Heiwang iron, and also made one prediction with normal mine water inflow during the iron mining operation. It turned out that the result can match with the actual prediction data, which make it possible to predict the mine water inflow with the prediction of Artificial Neural Network.

The water inrush from coal mine floor is a typical catastrophic process. A catastrophic theory is applied to water bursting in pit footwall for the first time. Through the research on lost stabilization of energy in the floor system of coal mine, a cusp catastrophic model applied to forecast water bursting from coal mine floor is put forward. The formulas of the critical stress, the strain and the released energy of the floor are developed when the floor system lost stabilization. So a new theory approach is offered for the forecast of water inrush from coal mine floor.

Environmental variations and the influences on water resources are complicated. According to a great number of the statistical data of Hebei province in Northern China since the 1950s, the analyzing indicated that the water resources volume in Hebei province trended towards decreasing during the recent 50 years as the variations of natural environment and human activities increasing. Precipitation reducing and air temperature rising are the basic cause of leading to the water resources decreasing. The continual lowering of groundwater level, which was created by the excess development of groundwater, not only caused surface runoff decreasing but also made groundwater recharge lessening. The level increase of crop output directly consumed a great lot of water resources, simultaneously had farmland evapotranspiration strengthened, and also brought about surface runoff and groundwater recharge decrease.

Hydrodynamic dispersion experiment was done with unsaturated silt loam. Depend on mass conservation law, the formulas to calculate coefficient of hydrodynamic dispersion was developed. According to the data of soil water and salt regime measured from the upright soil column, the coefficient of hydrodynamic dispersion was calculated, and the relation between hydrodynamic dispersion and average flow velocity in soil voids was built up. This approach has clear concept of physics, and the formulas are simple and applied.

Based on the analysis of regional geology and hydrogeological conditions of Wannian mine of Fengfeng coalfield, according to field's borehole data, geological data and hydrogeological data, we use GMS software to make the three-dimensional visualization strata modeling in Wannian mine of Fengfeng coalfield. Through cutting geological model built in different directions or at different levels and rotating to different directions and different angles, the complex underground geological environment is displayed in three-dimension, which helps geologists to analyze the geological conditions and solve various geological problems.

The topography is low and flat in the estuarine region of the Yangtze River, where waterlog and salt-affected soil is all through a latent threat to the agricultural development for long time. After the Three-Gorge Project is built up, the Three-Gorge Reservoir adjusts seasonably runoff will impact on the dynamic of soil water and salt in the region. These influence relations are very complicated. In spring, it will make the river water level up that discharge increases, so it will be not in favor of desalting. At the same time, mineralization degree of groundwater will decrease, in favor of desalting. In autumn-winter, it will make the river water level down that the discharge decreases, in favor of desalting. But, the mineralization degree of groundwater will increase, simultaneously salty tide invasion will strengthen, so not in favor of desalting. The elementary predicted result of numerical simulation shows that salification will be bigger in autumn than desalinization in spring. The impact degree of the project on the regime of soil salt will be gradually weakened along the river up from the estuary, the nearer to the sea, the bigger the impact, and from cross profiles, the nearer to the river, the bigger the impact. Especially within the range of 4 kilometers off the river, it is more possible that soil will produce salification or secondary salinization.

China is a big country of coal production, in the coal mining process, the great massive mine drainage has caused not only the waste of groundwater resource, but also environmental pollution. On the other hand, mining production and life supply water is very scarce. According to the mine water features, the majority of mine drainage water belonging to the mine water containing suspended, the mine water needs to do the necessary purification then can be used. That purification mainly eliminates is the suspended. In this paper, the method of purification and the technological process about mine water are discussed. The main methods of handling are coagulation, sedimentation, filtration and disinfection. According to different characteristics of water quality, different ways of handling and technological processes have to be chosen. Finally, the purification and utilization of mine water are shown through practical examples, Pingdingshan Coal Group Company, Wannian Coal Mine of Fengfeng Group Limited Company and Tangshan Coal Mine of Kailuan Group Company, to have obvious social, economic and environmental benefits.

According to the data of climate and runoff from 68 weather stations and 105 hydrologic stations in Hebei province between 1956 and 2000, the change of climatic essential factors and runoff are analyzed. Since the 1960s, the average annual temperature in Hebei province has been increasing gradually. Compared with the 1960s, the temperature in the 1990s has risen 0.9°C. From the age, the average annual evaporation as a whole in Hebei province has appeared a tendency to decline. And it descends 62mm every ten years on average. The average year’s precipitation has gradually diminished by the years. Compared with the 1950s, the precipitation in the 1990s has decreased 60mm. The average years runoff of the whole province, which declines 19.4×108m3 every ten years on average, emerging a gradually decreasing trend from the 1950s to the 1990s, is120.2×108m3. With the decrease of the precipitation and the rise of the temperature, the runoff declines. The models of climatic essential factors and the runoff established by utilizing the multiple regression analysis are logarithmic non-linear functions. Obviously, the impact of precipitation variety on the runoff is more than the effect of the temperature or the evaporation change on the runoff by the sensitivity analysis. According to the prediction of the future climatic change with regard to the runoff, the whole province runoff will alter from 114.36 to 138.24×108m3 in 2030. Similarly, the runoff will vary from 106.8 to 137.8×108m3 in 2050.

The numerical simulation for the Small Punch creep (SP-C) tests is conducted using a Finite Element method. The objective of the present study is to obtain the deformation states of the SP-C specimen and to estimate the feasibility of SP-C test method for high-temperature creep properties. The emphasis is put on the relationship between the equivalent creep strain and the central deflection of the SP-C specimen. The time history of central deflection and equivalent creep strain is obtained by finite element method and the effects of the load, temperature and material properties on the relationship of central deflection and equivalent creep strain are discussed. From the numerical results, the relationship between the central deflection and the equivalent creep strain is approximately independent of load, temperature, and material properties. As a farther result, the high temperature creep properties of the 12Cr1MoV steel are appraised by numerical simulation. The results are in good agreement with the results from the standard test method. The results indicate that the small punch test technique is an effective method for the evaluation of the high-temperature creep properties of materials.