The Research On Drilling Fluid Technology Under Ultra-deep Well And Ultra-temperature

As China's economy high-speed growing and the increasing demand for oil energy , the proportion of petroleum imports has reached 50% in 2009, a new round of resource assessment showed that the oil resources of the shallow nearly depleted, the remaining oil and gas resources are mainly distributed in the deep burial ground, 70% situates on more than 5,000 meters. Therefore, the development of oil and gas resources in deep strata which is the necessary and important strategic initiatives to protect national energy security of supply. It is very important that the ultra-deep drilling technology development and application of oil consumption for such a large demandent country in state-wide significance and prospects: Firstly, deep, ultra-deep drilling technology will accelerate our new areas, new areas, new layers, especially in deep oil and gas breakthrough, the discovery of new construction, new reservoir to maximize oil and gas resources to meet the needs of our country; And then, it would be proven recoverable reserves of oil and gas, increase oil and gas reserves, the realization of China's oil and gas resources to succeed target as soon as possible; What is more, it could accelerate the speed of China's oil and gas exploration and development, to ensure self-sufficiency ratio of oil and gas resources in China and the country's energy security.China's main oil and gas reserves replacement area -the basin of Songliao, Bohai Sea, the Tarim, Junggar and Sichuan where the deep reservoir temperatures up to 200 ~ 260℃. Evaluation of domestic drilling fluid technology and equipment, high temperature capability are below 180℃, 200℃above the drilling fluid against ultra-high temperature technology is a worldwide problem, is key to the success of deep drilling, major oil companies has long been monopolized by the United States, the domestic anti- ultra-high temperature drilling fluids mainly depend on foreign technology. Nearly three decades, the state with the three major oil companies invest a lot of resources to conduct research, not made much progress. Anti-ultra-high temperature drilling fluids has become China's development of oil and gas resources in deep strata of the main technical bottlenecks. Therefore, in-depth system to conduct deep drilling Jue Ding Cheng Bai-related anti-ultra-high temperature above 200℃the bottleneck technical problems of drilling fluid, for breaking the blockade of foreign technology to China for the domestic exploration and development of deep oil and gas reservoirs to provide technical support, significantly enhanced our drilling engineering services in the international core competencies, to ensure national energy security, are of particular importance.In this paper, resistant to high temperatures in recent years was handling agents and drilling fluid system was reviewed, and presented problems and technical ideas to be taken, namely through the development of Zuanjing Ye temperature protection agents, anti-temperature performance of the existing system improvements and Create a new drilling fluid system to dramatically improve the anti-drilling fluid temperature capability.First of all, analysis of the mechanism of high temperature drilling fluid: As the temperature increases, the performance of the drilling fluid will change, will produce high-temperature clay dispersion, high temperature and high temperature inactivation of coalescence, handling agents will produce high-temperature degradation, high pay joint role, while the surface treatment agent in the high temperature desorption of clay, high temperature to hydration, the mechanism based on the above analysis, the high temperature treatment agent should possess the molecular structure requirements.Developed a high temperature fluid protective agent (GBH), GBH in the drilling fluid system has a synergistic effect in that the fluid resistance to high temperature fluid loss, high temperature drilling fluid system's overall stability and temperature resistance is improved , anti temperature over 240℃, and through the optimization of other anti-temperature treatment agent to finalize the ultra-high temperature drilling fluid's basic formula is: 4% sodium soil +1% GBH +6% GJL-Ⅱ+4% GJL-Ⅰ+4% GFD +0.2% GZN + weight spar.Preparation of ultra-high temperature drilling fluid system suitable for different temperatures (180℃~ 240℃) and density (1.03 ~ 2.28 g/cm3) requirements, and inhibition of drilling fluid has a good performance and anti-pollution performance of cuttings, the protective effect of reservoir Well, dealing with agents and drilling fluid system can meet the environmental requirements. And high temperature were carried out evaluation of drilling fluid. The formation of ultra-high temperature drilling fluid technology in deep wells of moshen 1, guchen 4, lundong 1, keshen 2 and keshen 1 and on-site applications (temperature 161 ~ 181℃), to solve the deep, high temperature drilling fluid rheology control and the difficult problem of water loss control, security, it successfully completed the drilling of five exploratory mission."Ultra-deep ultra-high temperature drilling fluid technology" could provide support of technical for drilling, deep drilling to improve the speed of the complexity and shorten the drilling cycle, reduce drilling costs and speed up the process of exploration and development of oil and gas resources which has important theoretical and practical value, for the protection of China's energy security is of great strategic significance.