The Class-Ⅲ oil reservoirs of Lasaxing oilfield in the Daqing Oil Fields complex have geological oil reserves of 1.86 billion tonnes,an oil recovery of 39%,with remaining reserves accounting for more than 45%of the t...The Class-Ⅲ oil reservoirs of Lasaxing oilfield in the Daqing Oil Fields complex have geological oil reserves of 1.86 billion tonnes,an oil recovery of 39%,with remaining reserves accounting for more than 45%of the total geological reserves of the oilfield.Therefore,they have considerable potential for future oil production.The current layered injection technologies fail to achieve effective control over the low single-layer injection rates since they can only produce low throttle differential pressure under low injection rates(5-20 m^(3)/d).In this study,a symmetrically-structured double-offset-hole injection allocator and a novel throttling component were developed.Their spatial layout was constructed and mechanical parameters were optimized using finite element analysis,which allows for expanding the flow rate range at low injection rates.According to experimental results,the throttle differential pressure increased from 0.2 MPa to 0.8 MPa at an injection rate of 5 m^(3)/d,and the range of the single-layer flow rates expanded from 20-70 m^(3)/d to 5-70 m3/d.The field test results show that the effective production of oil layers with medium and low permeability was achieved and that the ratio of producing oil layer thickness to the total reservoir thickness increased by 9.7%on average.Therefore,this study provides valuable technical support for the effective chemical-flooding-based development of Class-Ⅲ oil reservoirs.展开更多
By tracking and analyzing the research and practices of chemical flooding carried out in the Daqing Oilfield, NE China since the 1970 s, the chemical flooding theory, technology adaptability and existing problems were...By tracking and analyzing the research and practices of chemical flooding carried out in the Daqing Oilfield, NE China since the 1970 s, the chemical flooding theory, technology adaptability and existing problems were systematically summarized, and directions and ideas of development in the future were proposed. In enhanced oil recovery by chemical flooding, the Daqing Oilfield developed theories related to compatibility between crude oil and surfactant that may form ultra-low interfacial tensions with low-acidity oil, and a series of surfactant products were developed independently. The key technologies for chemical flooding such as injection parameter optimization and numerical simulation were established. The technologies of separation injection, cleansing and anti-scaling, preparation and injection, and produced liquid processing were developed. The matching technologies of production engineering and surface facilities were formed. Through implementation of chemical flooding, the Daqing Oilfield achieved outstanding performances with enhanced recovery rate of 12% in polymer flooding and with enhanced recovery rate of 18% in ASP flooding. To further enhance the oil recovery of chemical flooding, three aspects need to be studied:(1) fine characterization of reservoirs;(2) smart and efficient recovery enhancement technologies;(3) environment friendly, high-efficiency and smart matching processes.展开更多
This article expounds the vital role undertaken by telemetry in monitoring and assessment in flood control in China. By analyzing the data from their surveys, the authors give an all-round exposition of problems in th...This article expounds the vital role undertaken by telemetry in monitoring and assessment in flood control in China. By analyzing the data from their surveys, the authors give an all-round exposition of problems in the country’s drive for disaster reduction and propose countermeasures in the fight against the possible flood problems in the future.展开更多
To compare the oil displacement mechanisms and performances of continuous phase flooding agent(traditional polymer solution) and dispersed phase flooding agent(particle-type polymer SMG dispersion), the particle phase...To compare the oil displacement mechanisms and performances of continuous phase flooding agent(traditional polymer solution) and dispersed phase flooding agent(particle-type polymer SMG dispersion), the particle phase separation of SMG dispersion migrating in pores was simulated by using the microfluidic technology. Theoretically guided by the tree fork concentration distribution of red cells in biological fluid mechanics, the concentration distribution mathematical model of SMG in different pores is established. Furthermore, the micro and macro physical simulation experiments of continuous and dispersed phase flooding agents were carried out. The results show that the continuous flooding agent enters all the swept zones and increases the flow resistance in both larger and small pores. On the contrary, the particle phase separation phenomenon occurs during the injection process of dispersed flooding agent. The SMG particles gather in the larger pore to form bridge blinding, and the carrier fluid displace oil in the small pore. Working in cooperation, the SMG particle and carrier fluid drive the residual oil in the low permeability layers step by step and achieve the goal of enhanced oil recovery. The laboratory experimental results indicate that, the oil increment and water reduction effect of dispersed flooding agent is much better than that of continuous flooding agent, which is consistent with the field test results.展开更多
近年来洪水引发的中小河流堤防溃决等洪水灾害风险问题凸显,因此进行溃堤洪水风险分析对于加强中小河流的洪水管理及减少溃堤洪水带来的损失具有十分重要的意义。以江西省罗塘河为例,借助MIKE软件中的MIKE 11、MIKE 21及其耦合模块对罗...近年来洪水引发的中小河流堤防溃决等洪水灾害风险问题凸显,因此进行溃堤洪水风险分析对于加强中小河流的洪水管理及减少溃堤洪水带来的损失具有十分重要的意义。以江西省罗塘河为例,借助MIKE软件中的MIKE 11、MIKE 21及其耦合模块对罗塘河遭遇10a一遇及20a一遇洪水进行溃堤洪水演进模拟。然后依据灾害系统理论从洪水的危险性和易损性两方面选择淹没水深、淹没流速、淹没历时等7个指标构建溃堤洪水风险评价指标体系。最后利用GIS技术与层次分析法对罗塘河洪水风险进行了评价。结果表明:洪水危险区面积为0.19 km 2,占研究区总面积的2.18%,主要分布在地势低洼的富港地区;重灾区和中灾区面积为1.25 km 2,占研究区总面积的14.37%,主要分布在重文和蒋元乐家;安全区为研究区域内洪水没有到达并且地物覆盖价值较低的地区,包括游家店、下胡、大塘杨家和马山等处。研究成果可为中小河流防洪规划、避洪转移等提供参考依据。展开更多
基金sponsored by the key consulting project of the Chinese Academy of Engineering entitled Research on the Sustainable Development Strategy of China's High Water-cut Old Oilfields(No.2019-XZ-15)the National major project entitled Large Oil and Gas Field and Coalbed Methane Development(No.:2016ZX05010006).
文摘The Class-Ⅲ oil reservoirs of Lasaxing oilfield in the Daqing Oil Fields complex have geological oil reserves of 1.86 billion tonnes,an oil recovery of 39%,with remaining reserves accounting for more than 45%of the total geological reserves of the oilfield.Therefore,they have considerable potential for future oil production.The current layered injection technologies fail to achieve effective control over the low single-layer injection rates since they can only produce low throttle differential pressure under low injection rates(5-20 m^(3)/d).In this study,a symmetrically-structured double-offset-hole injection allocator and a novel throttling component were developed.Their spatial layout was constructed and mechanical parameters were optimized using finite element analysis,which allows for expanding the flow rate range at low injection rates.According to experimental results,the throttle differential pressure increased from 0.2 MPa to 0.8 MPa at an injection rate of 5 m^(3)/d,and the range of the single-layer flow rates expanded from 20-70 m^(3)/d to 5-70 m3/d.The field test results show that the effective production of oil layers with medium and low permeability was achieved and that the ratio of producing oil layer thickness to the total reservoir thickness increased by 9.7%on average.Therefore,this study provides valuable technical support for the effective chemical-flooding-based development of Class-Ⅲ oil reservoirs.
基金Supported by the China National Science and Technology Major Project(2011ZX05052,2011ZX05010)
文摘By tracking and analyzing the research and practices of chemical flooding carried out in the Daqing Oilfield, NE China since the 1970 s, the chemical flooding theory, technology adaptability and existing problems were systematically summarized, and directions and ideas of development in the future were proposed. In enhanced oil recovery by chemical flooding, the Daqing Oilfield developed theories related to compatibility between crude oil and surfactant that may form ultra-low interfacial tensions with low-acidity oil, and a series of surfactant products were developed independently. The key technologies for chemical flooding such as injection parameter optimization and numerical simulation were established. The technologies of separation injection, cleansing and anti-scaling, preparation and injection, and produced liquid processing were developed. The matching technologies of production engineering and surface facilities were formed. Through implementation of chemical flooding, the Daqing Oilfield achieved outstanding performances with enhanced recovery rate of 12% in polymer flooding and with enhanced recovery rate of 18% in ASP flooding. To further enhance the oil recovery of chemical flooding, three aspects need to be studied:(1) fine characterization of reservoirs;(2) smart and efficient recovery enhancement technologies;(3) environment friendly, high-efficiency and smart matching processes.
文摘This article expounds the vital role undertaken by telemetry in monitoring and assessment in flood control in China. By analyzing the data from their surveys, the authors give an all-round exposition of problems in the country’s drive for disaster reduction and propose countermeasures in the fight against the possible flood problems in the future.
基金Supported by the China Postdoctoral Science Foundation(Grant No.2018M641610)China National Science and Technology Major Project(2016ZX05025-003)
文摘To compare the oil displacement mechanisms and performances of continuous phase flooding agent(traditional polymer solution) and dispersed phase flooding agent(particle-type polymer SMG dispersion), the particle phase separation of SMG dispersion migrating in pores was simulated by using the microfluidic technology. Theoretically guided by the tree fork concentration distribution of red cells in biological fluid mechanics, the concentration distribution mathematical model of SMG in different pores is established. Furthermore, the micro and macro physical simulation experiments of continuous and dispersed phase flooding agents were carried out. The results show that the continuous flooding agent enters all the swept zones and increases the flow resistance in both larger and small pores. On the contrary, the particle phase separation phenomenon occurs during the injection process of dispersed flooding agent. The SMG particles gather in the larger pore to form bridge blinding, and the carrier fluid displace oil in the small pore. Working in cooperation, the SMG particle and carrier fluid drive the residual oil in the low permeability layers step by step and achieve the goal of enhanced oil recovery. The laboratory experimental results indicate that, the oil increment and water reduction effect of dispersed flooding agent is much better than that of continuous flooding agent, which is consistent with the field test results.
文摘近年来洪水引发的中小河流堤防溃决等洪水灾害风险问题凸显,因此进行溃堤洪水风险分析对于加强中小河流的洪水管理及减少溃堤洪水带来的损失具有十分重要的意义。以江西省罗塘河为例,借助MIKE软件中的MIKE 11、MIKE 21及其耦合模块对罗塘河遭遇10a一遇及20a一遇洪水进行溃堤洪水演进模拟。然后依据灾害系统理论从洪水的危险性和易损性两方面选择淹没水深、淹没流速、淹没历时等7个指标构建溃堤洪水风险评价指标体系。最后利用GIS技术与层次分析法对罗塘河洪水风险进行了评价。结果表明:洪水危险区面积为0.19 km 2,占研究区总面积的2.18%,主要分布在地势低洼的富港地区;重灾区和中灾区面积为1.25 km 2,占研究区总面积的14.37%,主要分布在重文和蒋元乐家;安全区为研究区域内洪水没有到达并且地物覆盖价值较低的地区,包括游家店、下胡、大塘杨家和马山等处。研究成果可为中小河流防洪规划、避洪转移等提供参考依据。