Advanced Materials Research Vols. 734-737

Abstract: Grey system theory is a kind of method and system that contains something known and unknown. A completely definitive number is called a white number, while for one that does not have a definite value but a general range is called a grey number, whose greatest attribute is forecasting single data series. The grey theory was applied to predict the development index of X-L oilfield, including oil production, water production and water cut. The result is of very good accuracy.

Abstract: Through thirty years of development, Lianhua oil reservoir has entered into the stage of low-speed development. At present, the rate of oil production is only 0.0033%. Firstly, it divided development stage of Lianhua reservoir and analyzed production characteristics of each stage. By mean of the production decline curve, it predicted the recovery of the reservoir to estimate the ultimate recoverable reserves and the recovery percent. The results show that the ultimate recoverable reserves of Lianhua reservoir was about 50.813×10⁴ t, the ultimate recovery was 13.177%, the recovery percent of recoverable reserves had reached up to 95.094%, and the remaining recoverable reserves were rare. Therefore, it urgently needs to find a more reasonable development model to do secondary development of Lianhua reservoir. The conclusions have an important realistic significance of guiding secondary development of the Lianhua reservoir.

Abstract: Seismic exploration of petroleum is a kind of high technology which integrated hardware and software. The improvement of software engineering has produced an active influence on seismic exploration. The recent advance mainly expressed on acquisition, processing and interpretation of high frequency three dimensional seismic data. Application of new algorithm and super integrate large-scale software can improve the accuracy and efficiency of the petroleum discovery. Development seismic is new frontier of seismic application. Its a new branch of learning which makes full description and dynamic detection during petroleum exploration. It need use manners of oil and gas reservoir observation and information processing technique, combining with the data of drilling, geology and reservoir engineering etc. This can also take related hardware and software technological advances and development.

Abstract: SAGD technology is utilized to exploit heavy oil in Du 84 block Shu 1 area of Liaohe Oilfield, the temperature of wellhead produced fluid can reach up to 170-180°C. To avoid wasting the thermal energy, a set of scheme of cascade utilization of waste heat was proposed to combine the generation of electrical energy and heating in this paper. The generating capacity, heating area and its economic efficiency are calculated and analyzed in this scheme. In addition, taking the annual total cost of the condenser as the objective function, the parameters of the condenser are optimized by using optimal function in MATLAB software. The results can be used to conduct the design of the waste heat utilization system in practical project. Keywords-; Energy saving; optimal design; low temperature waste heat; SAGD

Abstract: The northeast part of China has rich coal resources and many coal basins. It has good prospects for CBM exploration. By drilling data analysis, this article evaluates coal seam characteristics and predicts seam thickness and spatial distribution of Chengzhihe formation. Jixi Basin has wide coal distribution, high seam gas content, good capping conditions, through a comprehensive analysis of factors such as coal seam thickness, depth and degree of metamorphism. the south of Jixi Basin is a key exploration area for CBM exploration and development in the northeast part of China.

Abstract: Miscible and/or near miscible CO2 flood are among the most widely used enhanced oil recovery techniques. The successful design and implementation of a miscible gas injection project is dependent upon the accurate determination of MMP^[1]-[9], the pressure above which the displacement process becomes multicontact miscible. This paper presents a method to get the characteristics curve of multicontact. The curve can illustrate the character in the Miscible and/or near miscible gas injection processes, based the curve, From the change of characteristics curve of multicontact ,we can known the type of the displacement, and the influence of injection gas to the MMP.

Abstract: During well drilling and petroleum production in deepwater, wellhole temperature changes will cause annular pressure buildup (APB), which is of great danger to casing strings. Based on previous research results, this paper introduces the traditional bulk modulus elasticity calculation method of mixed gas and liquid into annulus fluids, to predict annular pressure buildup by thermal when gas mixture is used. Pressure mitigation effect of common used compressible fluid is investigated and compared with experiment results from references. Through engineering case, the changing rule of mixed fluid bulk modulus versus gas volume and impact of mixed fluid volume on annular pressure are calculated. It shows that bulk modulus obtained in this paper has small errors compared with simulation experiment. But the errors are acceptable in engineering environment. And so, annular pressures needed in a well can be predicted and controlled precisely by adjusting gas volume as shown in examples.

Abstract: Discovered in recent years, Chang 4+5 reservoir group of Yanchang Formation in Jiyuan area is ultra-low permeability reservoir. The evaluation and prediction of the reservoir is the most critical technology in reservoir development. Comprehensive analysis with multiple research approaches shows that the storage potential of the ultra-low permeability reservoir is jointly controlled by sedimentation and diagenesis. Sedimentary factor includes lithology and sedimentary facies, two basic factors affecting the storage potential. The reservoir lithology is of fine-grained debris-arkose and miliary arkose. Pore types are mainly intergranular pores and dissolved pores. The sandstone microfacies in the delta front underwater distributary channel has the best storage potential. Diagenetic factors, including diagenesis types, evolution, intensity, combination etc., have direct influence on the reservoir storage potential. Compaction and calcite cementation are the main factors that weaken the storage potential, whereas carbonate dissolution, especially the dissolution of feldspar plays an important role in the improvement of the storage potential.

Abstract: Based on the analysis of the relationships between the conditions of structures, sedimentations, source rocks, cap rocks, faults, oil and gas migration passages and traps and hydrocarbon accumulation, the controlling factors of hydrocarbon accumulation and distribution was studied in Talaha-changjiaweizi area. It is held that the source rocks control the hydrocarbon vertical distribution, the drainage capabilities control the hydrocarbon plane distribution, fracture belts control the hydrocarbon accumulation of Talaha syncline, underwater distributary channel is a favorable accumulation environment and reservoir physical properties control the oil and water distributions. Therefore, it is concluded that source rocks, fracture belts, sedimentary microfacies and reservoir physical properties are the main controlling factors of hydrocarbon accumulation and distribution in Talaha-changjiaweizi area.

Abstract: Deep basin gas, which is trapped deep in a basin, is a kind of unconventional natural gas. It is also one of the important unconventional gas resources. In the previous studies of the mechanism of deep basin gas accumulation, force balance and material balance are considered as essential conditions for the formation of deep basin gas reservoirs. However, the gravity of natural gas is not fully taken into account in the analysis of force balance. In this dissertation, the density of natural gas under the condition of underground temperature and pressure is calculated by using the EOS. The result shows that the density of natural gas cannot be neglected and the PR EOS is applicable to the analysis of the relationship between the volume of natural gas and the condition of underground temperature and pressure.