Applied Mechanics and Materials Vols. 423-426

Abstract: The basic prescription of the potassium sulfate drilling fluid is: 5% bentonite ＋0.4％Na₂CO₃ ＋5.0％K₂SO₄ ＋1000ppmDCL ＋200ppmDesco ＋100ppmAlcome ＋500ppmSAP＋ 1000ppmLT ＋1000ppmKEL. The content of K+ is 50000mg/L. The drilling fluid has appropriate viscosity, gel and filter loss. The shale rolling recovery rate is bigger than 85%. The static swelling rate is smaller than 2%. The corn damage is less than 20%. The mechanism of protect formation is the K+ ability of preventing the clay from hydrating and swelling, the adsorption ability of formation protecting agent and the cooperating role of K+ and formation protecting agent. The potassium sulfate drilling fluid was used in fang-3 outer section of the Song-fang-tun oilfield. It was shown that the drilling fluid could meet the drilling demand in this oilfield.

Abstract: Integrated sintering between magnetization and dealkalization, processed on red mud firstly. DWS-50 was used to detect the rate of dealkalization, and phase transition of elemental iron in red mud was analyzed by XRD. By effect of sintering temperature and sintering time on red mud, the results showed that integrated sintering on red mud between dealkalization and magnetization was feasible.

Abstract: Deposition of solid elemental sulfur may arouse severe damage to the formation and significantly affect the gas deliverability in sour gas reservoirs. As one main measure of stimulation, hydraulic fracturing always ceases to work due to the sulfur deposition in the fractures. To have a better understanding of the failure of fracture conductivity caused by sulfur deposition and learn the degree of fracture conductivity improved by acidification, an experimental was implemented and studied. In this paper, both the sulfur powder and an artificial fractured core were employed to simulate the process of sulfur deposition in the fractures. A further step was made to inject some hydrochloric acid into the blocked fracture caused by sulfur powder. The result showed that the fracture conductivity could be greatly reduced by the sulfur deposition. The fracture conductivity can be decreased by 17%~47% due to sulfur deposition. However, to some degree, acid-fracturing can improve the conductivity of fracture by eroding the surface of fracture. This means the failure of fracture blocked by sulfur deposition can be improved by acidification.

Abstract: The 3# high rank coal in Qinshui basin frequently takes place of falling block, sloughing hole, leaking and pipe-stuck during drilling operation. The third open of 12-11-3H well in Qinping is consist of 2 main-branch and 6 sub-branch, using fuzzy-ball drilling fluid for 3 days accomplishing a footage of 4 189.49m. In order to adjust performance of drilling fluid, mix 4 fuzzy-ball drilling fluid additives SDS, SDBS, HES PAM together according to different well condition. The density of this drilling fluid is from 0.96 to 1.08g/cm³. The plastic viscosity of it is from 7 to 17mPa^.s, the yield value is from 4.0 to 10.22Pa. After using this fuzzy-ball drilling fluid, the drilling rate has increase to 95%, completing the geological demand with an average drilling rate of 12.65m/h. Compared with adjacent well, the drilling rate has been raised 11.55% with no serious falling block, sloughing or leaking in whole well. However the solid control equipments still need to be strengthened for further improving drilling rate and economic benefits.

Abstract: The solid free completion fluid is the KCl-polymer system, it has the good inhibitory and stabilize the clay. The corrosion rate is 0.0775 g/m2·h, for different permeability core, the degree of injury is less than 20%.Use completion fluid to reduce oil layer damage of main mechanism for the effect of k+, inhibition of polymer and the synergy of K + and polymer.

Abstract: Sintered board and porous board was used to be gas distributor of air-dense medium fluidized bed in the experiment, the influence of different gas distributor settings to fluidization and separation characteristics was investigated; The results showed that, under the same conditions, the pressure drop of sintered board gas distributor is greater than porous board gas distributor. The pressure drop of gas distributor is proportional to the layers of filter cloth and air volume. The uniformity and stability of sintered board gas distributor with 1 layer filter cloth is bad, sintered board gas distributor with 2 layers filter cloth and porous board gas distributor with 5 or 6 layers filter cloth can obtain a better fluidizing effect; Conducting separation experiment on fat coal of 50 ~13mm under the suitable air volume, porous board gas distributor with 5 layers filter cloth has the best separation accuracy, and its probable error Ep value is 0.05 g/cm³.

Abstract: In order to make clear the effect of material on the vibration crusher which is a rigid-loose coupling dynamics system, a crushing experiment of limestone granules was made. The limestone granules were restricted in a rigid metal containers, and they were crushed by the pressure from the press. The constitutive relation-nonlinear hysteresis of granules in the crushing process is gained. The effect of the maximum pressure and the granular layer thickness on the constitutive relation and granule size distribution is obtained. The relation between energy absorption and crushing ratio is acquired. This experiment provides some theoretical support for the design of new vibration crusher.

Abstract: For solving the problems of high energy consumption and high capacity of water-absorption, microwave dehydration technology of lignite was studied in this paper. A self-developed microwave system was used for the experiment on dehydration of lignite from eastern Inner Mongolia. It was proved that the condition of moisture migration was improved and microwave dehydration had a unique mechanism. By analyzing the effects of microwave powers, coal particle sizes, and lignite qualities on drying characteristics, it was found that the moisture decreased when the microwave power increased. it was found that the higher the power was, the faster the moisture decreased; the smaller the particle size was, the faster the moisture decreased; the less the lignite was, the faster the moisture decreased. Through the scanning electron microscope analysis, it was concluded that microwave had no significant effect on the smooth particles, and the fibrous particles and clusters particles tended to be smooth under the effect of microwave. Therefore, the interface of lignite was relatively stable, and not easy to reabsorb water after microwave.

Abstract: Considering the impact of gas-liquid two-phase variable mass flow in horizontal wellbore, combined with the principle of mass, momentum and energy conservation, a simple prediction model was developed to simulate the steam injection performance of horizontal wells completed with slotted liners. Based on the model, the profiles of steam pressure, temperature, quality and flow rate to the reservoir along the slotted horizontal wellbore were studied. The results show the steam pressure, temperature, quality and steam flow rate to the reservoir all gradually drop from the horizontal heel to the toe. However, the decrease of steam pressure and temperature are not so remarkable, but it is conspicuous for steam quality and steam flow rate to the reservoir. It is crucial to develop the techniques to guarantee a uniform flow along the horizontal wellbore.

Abstract: Metal hafnium has research significance as a rare metal. Metal hafnium, hafnium alloy and hafnium compounds are made a simple introduction, the distribution of hafnium resource is summarized at home and abroad, and the processing method of hafnium resource and the development prospect of comprehensive performance of hafnium resource are discussed.