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The Attribute Optimization Method Based on the Probability Kernel Principal Component Analysis and Its Application
Jingjing Zheng,
Yun Wang,
Chunying Yang
Issue:
Volume 7, Issue 1, January 2019
Pages:
1-6
Received:
8 November 2018
Accepted:
6 December 2018
Published:
21 January 2019
Abstract: The principal component analysis (PCA) is the most common attribute optimization analysis techniques, but it is a linear method and exists the problem of lack of probability model and the absence of higher-order statistics information. It has poor comprehensive ability to complex non-linear attributes. Therefore, in order to overcome two shortcomings of the principal component analysis (PCA) and improve the effect of attribute optimization, this paper studies the probability kernel principal component analysis (PKPCA) method which is based on Bayesian theory and kernel principal component analysis (KPCA). First, the sample data are mapped to the high dimensional feature space, then define probability model of the data in high-dimensional space, and finally, expectation maximization (EM) estimated is used to get the best results. This method has both the advantage of probability analysis and kernel principal component analysis (KPCA). It is able to effectively adapt to more complex reservoir conditions and can realize the non-linear probability analysis. The probability kernel principal component analysis (PKPCA) method is applied to reservoir prediction of the Southern oil fields in China. The predicted results show that the method can improve the precision of the attribute optimization, while improving the accuracy of the forecasts of reservoir.
Abstract: The principal component analysis (PCA) is the most common attribute optimization analysis techniques, but it is a linear method and exists the problem of lack of probability model and the absence of higher-order statistics information. It has poor comprehensive ability to complex non-linear attributes. Therefore, in order to overcome two shortcomin...
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Discussion on the Method of Evaluating Oil and Water Layers by Using Ratio of Deep Resistivity and Flush Zone Resistivity
Yang Kebing,
Li Shidong,
Wang Huijing,
Fu Kang,
Pan Xuefeng,
Zhang Junjie
Issue:
Volume 7, Issue 1, January 2019
Pages:
7-12
Received:
10 November 2018
Accepted:
3 December 2018
Published:
21 January 2019
Abstract: The depth-shallow resistivity ratio method for the same measuring point is an important method to identify oil and water reservoirs, But its application effect in conventional logging data is not good. By studying the invasion characteristics of resistivity curves of reservoirs, the ratio of deep resistivity and flush zone resistivity at the same measuring point is used to evaluate oil and water layers with a good effect. Further research shows that the ratio of deep resistivity to flushing zone resistivity can reflect the oil-bearing property of reservoir. The fact that the ratio of deep resistivity and flush zone resistivity of water layers in the same well is basically a constant supports this view, which can be deduced from Archie's formula. That is, the ratio of deep resistivity to flushing zone resistivity is Rw/Rmf, which is the ratio of formation water resistivity to mud filtrate resistivity. On this basis, a method of evaluating oil and water reservoir by using the ratio of deep resistivity and flush zone resistivity is proposed. One is logging crossplot evaluation method, the other is apparent water saturation calculation and evaluation method. These two methods are not affected by the changes of lithology and resistivity of the reservoir, and do not need data such as porosity, rock-electro parameters and formation water resistivity, which can quickly identify oil and water layers. As the ratio between the deep resistivity and the resistivity of the flush zone is not related to the resistivity of the reservoir, it can be used to evaluate the low resistivity oil reservoir. The results show that it is effective to identify low resistivity reservoirs and it is a reliable method to evaluate low resistivity reservoirs.
Abstract: The depth-shallow resistivity ratio method for the same measuring point is an important method to identify oil and water reservoirs, But its application effect in conventional logging data is not good. By studying the invasion characteristics of resistivity curves of reservoirs, the ratio of deep resistivity and flush zone resistivity at the same m...
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Analytical Fracture Models for Overall Hydraulic Fracturing Reservoirs
Issue:
Volume 7, Issue 1, January 2019
Pages:
13-20
Received:
8 August 2018
Accepted:
20 September 2018
Published:
24 January 2019
Abstract: Hydraulic fracturing has become an indispensable stimulation measure for low permeability reservoirs, but how to quantitatively establish the fracturing geological model of this kind of reservoir has been an important factor restricting the progress of numerical research on overall hydraulic fracturing reservoirs. Based on the basic hypothesis of hydraulic fracturing and considering the heterogeneity of fracturing parameters, the mathematical models of fracture conductivity, permeability and porosity are deduced by reservoir engineering method, and the corresponding software is compiled to calculate quantitatively the geological parameters at any point of a single artificial fracture and its geological model is established. This model is applied to Sai 309 well area of Suijing oilfield in Changqing. Firstly, according to the geologic and development characteristics of the oilfield, unstable well test analysis method is used to quantitatively analyze the fracture parameters of fractured wells by using the existing formation testing data of wells, and then the critical geological factors and hydraulic fracturing operation parameters are selected to establish artificial neural network. Based on the trained neural network to predict the half-length of artificial fractures and the fracture conductivity of other wells without formation testing data, the porosity and permeability geological model of the fractures in hydraulic fracturing reservoir is established by using the above mathematical model, which lay a foundation for numerical simulation of fracture- matrix coupling in this kind of reservoir.
Abstract: Hydraulic fracturing has become an indispensable stimulation measure for low permeability reservoirs, but how to quantitatively establish the fracturing geological model of this kind of reservoir has been an important factor restricting the progress of numerical research on overall hydraulic fracturing reservoirs. Based on the basic hypothesis of h...
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Integrated Gas Lift Completion String for Ultra-Deep Reservoir
Issue:
Volume 7, Issue 1, January 2019
Pages:
21-25
Received:
5 December 2018
Accepted:
9 January 2019
Published:
29 January 2019
Abstract: Kenjiyak Oilfield, in Kazakhstan, is an ultra-deep oil reservoir of low porosity and ultra-low permeability, causing a myriad of technical problems when produced with conventional gas lift string. To address these problems, an integrated gas lift completion string has been developed. The completion string integrates fracturing, drainage and gas lift processes, and is capable of accomplishing multiple operations of zonal fracturing, quick flowback, reservoir protection, retrieving and gas lift production, etc., in one trip. This paper introduces the structure and working principles of this string, structural and performance characteristics of the key supporting tools. Meanwhile, it analyses the retrievable gas lift mandrel and drillable-retrievable packer. 47 wells' field application showed this completion string's maximum application was 4,287.63m, the maximum working pressure was 68MPa, the maximum single well daily yield was about 130t and the average drainage duration was 3 days, presenting significant operation performances. The integrated gas lift completion string is expected to provide strong technical support for oil production with low cost and high efficiency, thereby accelerating the development of overseas oilfields.
Abstract: Kenjiyak Oilfield, in Kazakhstan, is an ultra-deep oil reservoir of low porosity and ultra-low permeability, causing a myriad of technical problems when produced with conventional gas lift string. To address these problems, an integrated gas lift completion string has been developed. The completion string integrates fracturing, drainage and gas lif...
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Technical Innovation of Ultra-Deep Well Drilling Rig and Its Development Trend
Fang Taian,
Zhou Zhixiong,
Wu Changliang,
Yang Xiaoguang
Issue:
Volume 7, Issue 1, January 2019
Pages:
26-32
Received:
13 December 2018
Accepted:
3 January 2019
Published:
29 January 2019
Abstract: 8000-meter drilling rig and quadruple joint 9000-meter drilling rig have been developed for ultra-deep and complex wells of the complicated geological structure area in Tarim Basin, China. The key components of the drilling rigs are redesigned and innovated, including optimization of the high bearing capacity derricks and substructures and a completely new design of integrated single shaft drawworks with the compacted strand wire rope. The rotary table and its driving device with larger torque and load capacity, the high-pressure drilling pump with a high power, intelligent top drive system, casing running device with good compatibility, and automated pipe handling system are equipped. Field application shows that 8000 meters drilling rig, compared with the conventional 9000-meter drilling rig, can save equipment procurement costs by about 20%, reduce drilling operational costs 37%. In addition, the quadruple joint 9000-meter drilling rig can reduce the tripping time by more than 20%, and that the pressure is difficult to control in the complicated formation by conventional drilling rigs can be avoided to a certain extent. At the end of this paper, the advantages and the problems to be solved urgently of the ultra-deep well drilling rigs are expounded.
Abstract: 8000-meter drilling rig and quadruple joint 9000-meter drilling rig have been developed for ultra-deep and complex wells of the complicated geological structure area in Tarim Basin, China. The key components of the drilling rigs are redesigned and innovated, including optimization of the high bearing capacity derricks and substructures and a comple...
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A New Method for Analyzing the Dimension Error of Marine Steel Structures
Meng Linghe,
Zhang Shijian,
Xiao Liquan,
Wang Xuelian,
Yang Zilong,
Wang Zhihong
Issue:
Volume 7, Issue 1, January 2019
Pages:
33-39
Received:
10 October 2018
Accepted:
23 January 2019
Published:
15 February 2019
Abstract: With the strengthening of offshore oil exploitation, the construction of marine steel structures such as offshore oil platforms has been carried out on a large scale. During the construction process, the dimensional control and error analysis of marine steel structures is an important point. The dimensional error of marine steel structure is an important indicator reflecting the quality of marine steel structure construction. The marine steel structure is completed from structural design to offshore installation. The structural dimensional error must be strictly controlled and analyzed at each stage. It has important guiding significance for the design and construction of marine steel structure, ensuring final installation and safe production. Based on the summary of traditional size control and analysis methods, this paper introduces a new method of size control and analysis. The new method introduced in this paper uses the minimum two-passenger fitting technique, that is, the sum of all the deviation values is the smallest, so that the measured data can best match the design data, and the size error of the marine steel structure is represented by the magnitude and direction of the three-dimensional deviation. The three-dimensional deviation of each node is reflected objectively and actually, intuitive and reasonable, and the calculation program is written by AUTOCAD VBA, and the deviation value is quickly calculated, which has a good effect on on-site construction adjustment and error analysis.
Abstract: With the strengthening of offshore oil exploitation, the construction of marine steel structures such as offshore oil platforms has been carried out on a large scale. During the construction process, the dimensional control and error analysis of marine steel structures is an important point. The dimensional error of marine steel structure is an imp...
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Study on the Conditions of Biogas Fermentation from Distillers' Grains
Mengmeng Yu,
Qinghua Ding,
Zhifeng Lv,
Yuancheng Zhang
Issue:
Volume 7, Issue 1, January 2019
Pages:
40-46
Received:
26 December 2018
Accepted:
25 January 2019
Published:
19 February 2019
Abstract: The distillers' grains fermentation was studied, which was from ethanol fermentation of sweet sorghum stalk. The factors such as temperature, concentration, inocula, pH etc. were analysis. The results showed the optimal temperature was 55°C, the optimal weight concentration of distillers' grains was 3.3%, the amount of inocula was 1.5%, and the pH should be adjusted before fermentation. Under this condition, the maximum biogas production was 3710mL/d and appeared in the 9th day. The overall length of the fermentation period was 32d, and the biogas production rate was up to 509mL/gTS. The results could provide a theoretical basis for the fermentation of biogas production from distillers' grains.
Abstract: The distillers' grains fermentation was studied, which was from ethanol fermentation of sweet sorghum stalk. The factors such as temperature, concentration, inocula, pH etc. were analysis. The results showed the optimal temperature was 55°C, the optimal weight concentration of distillers' grains was 3.3%, the amount of inocula was 1.5%, and the pH ...
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