Applied Mechanics and Materials Vols. 316-317

Abstract: Well control safe is the prerequisite of safety drilling, especially for high temperature and high pressure horizontal wells. However, there are few papers about well control of horizontal well drilling, which mostly learn from vertical well control process. By means of analysis of the theory of gas kick, we conclude that underbalance, the bottom hole pressure is less than the formation pressure is the main means of gas invasion. During balance period, the gas also intrudes into wellbore through the way of direct invasion, diffusion invasion and replacement invasion, but the amount of gas kick is less, so the risk of well control is small. This paper also anlyses the kick tolerance, the kick tolerance decreases with the increasing of drilling fluid density when the formation pressure and drilling equipment is constant.

Abstract: The run of mine ore grade of Burma is 47.83%. According to the nature of the ore for the corresponding process, and the conditions of the test to explore, abstain to use a combined flowsheet for low magnetic separation - spiral chute - high gradient magnetic. The ultimate index for comprehensive grade of iron concentrate is 57.26%, at a total recovery of 83.07%, and obtain good experiment index.

Abstract: Steam flooding is an important method to improve the recovery factor heavy oil. Produce energy would consume a certain amount of crude oil in steam flooding; as a result, the evaluation of development effect of steam flooding should consider not only the degree of reserve recovery but also the heat utilization. In this paper, through the analysis of the mechanism of steam flooding, using reservoir engineering and numerical simulation methods, research the deposition, strata dip, steam injection rate, steam quality, production injection ratio and well completion method on the impact of steam flooding development effect in heavy oil.

Abstract: The paper focuses on the mineral characteristics of silicate-calcareous phosphate from Yunnan province and researches flotation conditions and flowsheet of phosphate. Using double-reverse flotation process to reduce the silicon and MgO, and a phosphate concentrate with P2O5 grade of 30.13%, SiO2 grade of 11.12% and P2O5 recovery of 80.16% was obtained.

Abstract: Abstract：A new technology of direct acid leaching vanadium without grinding and roasting was put forward, and the effects of leaching factors including dosage of sulfuric acid, type and dosage of assistant leaching agent, leaching time and temperature, liquid-solid ratio on the vanadium leaching rate were systematically investigated. The results show that vanadium leaching rate could be up to 92.58% under the optimal conditions of sulfuric acid dosage of 30%, MnO2 as assistant leaching agent and its dosage of 1.5%, leaching time of 6h, leaching temperature of 90°C, liquid-solid ratio of 1:1, and the leaching performance is perfect. Due to leaving out the high costing grinding system and the complex roasting system, the new technology has advantages in shortening the process, decreasing the cost, avoiding pollution generated by roasting comparing with the traditional technologies, and it can meet the requirement of modern metallurgy very well.

Abstract: The real road emissions characteristics of particulate matters (PM) and NO_X were researched based on velocity and acceleration of a typical China IV diesel bus which was fueled with five different fuels, including pure China IV diesel, pure coal to liquids (CTL), different blends of China IV diesel and CTL, of which the blend ratios of the CTL were separately 10%, 20%, 50% with the use of OBS-2200 and Engine Exhaust Particle Sizer (EEPS 3090). The research showed that the NO_X and PM emissions of bus fueled with five different fuels all show a gradual increase with the increase of velocity and acceleration. The CTL mixed with diesel can effectively reduce the NO_X emission, and the higher ratio of CTL, the more effective of reduction. The CTL mixed with diesel can reduce PN emissions for both nuclei modes and accumulated modes and reduce the peaks of PN emissions for accumulated modes so that reduce the PM emissions, the higher ratio of CTL, the more effective of reduction.

Abstract: Hydraulic fracturing is one of the effective means to enhance coal bed methane production for vertical wells. This paper presents an approach that uses pseudo-3D fracture propagation model to study the influence of petrophysical properties, differential stress, treatment conditions, etc. on fracture geometry. It is shown that differential stress, pump rate is proportional to fracture length and width; elastic modulus, Poisson`s ratio, pump rate, etc. is proportional to fracture height. The finding is of great importance for acquiring ideal fracture geometry.

Abstract: Three important aspects of phase-mining must be optimized: the number of phases, the geometry and position of each phase-pit (including the ultimate pit), and the ore and waste quantities to be mined in each phase. A model is presented in this paper in which, a sequence of geologically optimum pits are first generated and then dynamically evaluated to simultaneously optimize the above three aspects, with the objective of maximizing the overall net present value. The model takes into full account of the dynamic nature of the problem with respect to both time and space, and is robust in accommodating different pit wall slopes and different bench heights.

Abstract: The solvent flotation technique adopts organic solvent with low volatility as the second liquid phase, which could dissolve the components including emulsified crude oil, surfactant in the water. The modification of pH value, ion intensity, temperature, speed of air flow, and species of solvent could improve the efficiency of the flotation. The proposed method has been successfully applied to produced water treatment, the pharmaceutical industry sewage disposal and so on. It also has potential usage in sewage disposal of offshore oil field.

Abstract: SO42-/TiO2-ZrO2 was prepared by coprecipitation and dipping methods, and characterized by FT-IR, BET surface area measurement and NH3-TPD, and those results demonstrate the SO42- was loaded on the catalyst and the catalyst have enough surface area and pore size. The effect of methanol oil mole ratio, catalyst dosage, reaction temperature, reaction time on the conversion of waste cooking oil to biodiesel was investigated to find optimum reaction conditions. From the orthogonal experiments, the optimum reaction condition was shown as follows: methanol oil mole ratio is 25:1, catalyst dosage is 5% of oil, reaction temperature is 120°C, reaction time is 8h, the yield reached 96.68%.