Applied Mechanics and Materials Vols. 316-317

Abstract: According to low temperature, high salinity, heterogeneous and complex sandstone oil reservoirs in the Qaidam Basin. A novel profile modification agent (PMA) was developed by the author. The microscopic structure of the agent was analyzed by SEM. The PMA of 0.3% has stronger plugging capacity to cores. Its blocking coefficient was larger than 91%, and it was not less than 90% after being flushed with 20PV injected water. In parallel core test the agent could be used to adjust the reservoir permeability and enhance oil recovery substantially. The field test achieved good results.

Abstract: A kind of high oxidation rate and complex to concentrate copper oxide ore has been studied. The run-of-mine grade of Copper was 2.54%, with the oxidation rate of 79.13%. And the grade of Silver was 80g/t. The optimal grinding fineness was about to 71%. Use the best reagent combination which obtained by condition test, the final results was that the grade of Copper concentrate was 15.20% and the recovery rate was 56.85%, included silver 793.50 g/t.

Abstract: Gel treatment is increasingly used as permeability modifiers in reducing high water production. To analyze the influences of reservoir temperature on the performance of gel treatment, extensive numerical simulation study is undertaken to model the behavior of high temperature reservoirs. Polyacrylamide (PAM)/Cr3+ gel treatment and silicate gel method are compared with waterflooding through water-oil ratio and cumulative oil recovery. The results demonstrate that, for the case of common temperature, PAM/Cr3+ gel treatment results in highly decreased water-oil ratio compared with water flooding. PAM/Cr3+ gel have shown poor performance in high temperature reservoirs. However, silicate gel is still effective in high temperature reservoirs.

Abstract: The paper introduces the practical application of underground nearby orebody curtain grouting in Laixin iron mine. Based on the analysis of hydrogeology condition in the mine and the technical requirements of water control plans, the final water control plan introduced in the paper is chosen. Roadway horizontal drilling water-prospect grouting and transverse and slant drilling encrypting grouting are described, and quantities of the two projects are given. Finally, significant economic and environmental benefits caused by underground nearly orebody curtain grouting in Laixin iron mine are analyzed.

Abstract: Complex geological properties of oil reservoirs affect productivity of chemical flooding. Presence of bottom-water aquifer combined with heterogeneous reservoirs has been regarded as a problem which brings out reduction of recovery factor and high water-cut. A numerical reservoir simulator is used to investigate effects of aquifer on the performance of chemical flooding. By including the effects of bottom-water aquifer, productivity decreases significantly compared with that from non-aquifer case. Results from this study emphasize the importance of an accurate assessment of performance before implementing chemical flooding, especially in unfavorable condition such as bottom-water aquifer.

Abstract: Coal petrologic structure is important for the prediction of coal and the associated coalbed methane outburst during coal mining. This paper discusses the relationship between the response characteristics of natural gamma (GR), laterlog deep (LLD) and compensation density curve (RHOB), and the coal structures. Results show that the tectonic-coals (the coals with high breakage degree by tectonic structures) can be identified by the logging characteristics of low amplitude of GR (20-90 API), high amplitude of LLD (300-1800 Ωm), and low amplitude of RHOB (1.25-1.5g/cm³). It was found that with increasing degree of the breakage, coal pores and fractures become well developed, and thus reduce the bulk density of coal and the content of radioelement but more gas within the coal. This is the reason for logging performances of low amplitude of GR and RHOB, as well as high amplitude of LLD for the tectonic-coals.

Abstract: Fast Lagrangian Analysis of Continua in three Dimensions was adapted to establish numerical model of thin seam with Iron-sulfide-cores, based on the conditions of thin seam in Yanzhou Mining Area, and the influence of existing cores or not, cores in different positions, cores contents on mine pressure was studied. The results showed that, stress concentration and plastic zone is more easily to be formed in the coal around cores. When there are cores in coal, the bahaviors of abutment stress foreside the working face have no significant differences, the abutment stress curve is fluctuation and width or range of plastic zone little changed, but the boundary of plastic zone is fuzzy and radial. The boundary of plastic zone has some difference with the increasing of cores contents, but other macroscopic mine pressure behaviors has no significant differences. It is helpful to understand spalling mechanism of iron-sulfide-cores in thin seam.

Abstract: Bohai Sea is one of China's major offshore oil producing areas. With the development of oil exploitation, continuous oil spill accidents make serious damage to economy and environment. It is necessary to establish an effective oil spill monitoring emergency system. Based on GIS technology, this paper focuses on the implementations of monitoring data application functions in Sinopec Offshore Oil Spill Net Monitoring System. And it provides a reasonable solution for oil spill emergency aid decision-making system.

Abstract: The Southeast of Chong Qing Wu Feng – Long Ma Xi group is a national shale gas exploration and development key formation. Shale contains high clay minerals,It makes serious borehole instability and large of cuttings transport.The segment length of the horizontal well, is easy to form cuttings bed.Strong shale plastic makes ROP low. In this paper, It calculates the closed N-S equation based on the k-ε two-equation model by using numerical simulation method,studys the Φ 215.9 mm PDC bit´s nozzle diameters. When the center nozzle diameter is 12.70mm in a long horizontal section shale reservoir,It reachs the diameter of external nozzle is 8.74mm ~ 11.13mm optimal for PDC bit downhole flow field.The center and peripheral nozzle diameter of PDC bit should have a certain class difference, 2 ~ 5 grades is optimal. When the peripheral nozzle diameter is 11.13mm, the center of the nozzle diameter should be greater than or equal to 11.13mm for PDC bit flow field.The center nozzle diameter can not be smaller than the external diameter of the nozzle. The study can guide the shale reservoir horizontal section PDC bit design,improve ROP and cleaning rock,reduce the probability of cuttings settlement in the horizontal section.

Abstract: In order to reveal the cause of the largely distributing bitumen in Sinian reservoirs of Sichuan Basin, geochemical characteristics of the bitumen have been studied. From its microscopic optical characteristics, large proportion of the solid bitumen was found as cavity-filling. What’s more, the steroid and terpenoid biomarkers of the bitumen in the reservoir distribute normally, and 25-norhopane standing for degradation and washing function hasn’t been detected. Last but not least, condition of crude oil cracking was also possessed, as from the thermal evolution history of Sinian stratum of Sichuan. All of the above suggested that the bitumen was caused by oil cracking in the reservoir.