海上油田高效开发技术探索与实践

Exploration and practice of offshore oilfield effective development technology

在我国渤海湾相继发现40多亿t地质储量的原油,但这些原油多为稠油和重油,难以开发,在陆上油田开发经验不能用于海上,又无国际先例可借鉴的情况下,基于海上稠油开发历程及现状,深入分析了海上稠油油田开发面临的主要问题与挑战,有针对性地集成、创新了适合于海上稠油开采的先进技术,逐步建立完善了海上稠油高效开发思路和技术体系。该技术有效降低了油田开发成本,并成功地开发了被国际石油公司称为"21世纪挑战"的海上最大稠油油田。成功研发了开发海上边际油田的"三一模式"和"蜜蜂模式",应用于渤海边际油田开发实践,并探索出一套适用于海上油田开发的优快钻完井技术。在此基础上,为了实现渤海油田产量进一步增长和大幅度提高采收率,经过长期技术探索与矿场实践,大胆提出了海上稠油高效开发新模式,即模糊一、二、三次采油界限,通过技术创新和创新技术集成,使油田在投产初期迅速达到高峰产量并高速开采,始终保持旺盛生产能力;采取多枝导流、控制适度出砂、早期注水、注水即注聚、注水注聚相结合等技术;通过以聚合物驱为主的提高采收率技术、多枝导流技术、电潜螺杆泵举升技术和地面除砂工艺等技术体系,在最短的时间内采出更多的原油,达到最大采收率。基于高效开发新模式思想,成功开发了迄今为止世界海上最稠的渤海南堡35-2油田,并已在多个油田进行应用。这一创新的认识与实践,不仅为我国海上油田开发探索出一条新路,也为世界海上油田,特别是稠油油田的开发提供了新思路的思考。

More than 4 billion tons reserves has been found in China＇s Bohai Bay. However, most of the reserves are from heavy oil, which is hard to develop. The offshore heavy oil development could neither directly use onshore experience for the reference nor learn from international example. In this paper, the main challenges were analyzed and presented for offshore heavy oil development based on the characteristics of offshore oil field. The advanced heavy oil exploitation technology was integrated into the technology system, which was successfully introduced to develop the offshore heavy oil field named by international experts as one of the most challenging technologies in the 21st century. With the novel ＂THREE ONE MODE＂ and ＂BEE MODE＂ developed, many marginal oil fields can be developed economically in Bohai Bay. And the Optimized Fast Drilling Technology adapting to off- shore oilfield development was developed which could significantly reduce the drilling cost. In order to achieve the further growth of producing rate and enhanced oil recovery in Bohai oil field, the novel mode of offshore heavy oil efficient development was established after a long - term technology research and field practice. Different to the conventional development mode, this mode does not emphasize the primary, secondary, and tertiary recovery stages. It is a series of technologies which integrate, optimize, innovate and comprehensively apply in the three stages to increase production rate in early stage and prolong the high speed development time. It makes early stage water flooding, polymer flooding, polymer injection while water flooding as the policy of development technologies. Polymer flooding, as the main EOR technology, with drilling and production support technology system in multilateral wells, limited sand management and electric submersible progressive cavity pump technologies are integrated in the oil field operation to obtained the maximum benefits in the minimum time. With the efficient development mode of offshore oil field, NB35 -2 heavy oil field in Bohai Bay, with the most viscous heavy oil in the world, was successfully developed. And currently the mode has been widely applied to more offshore oil fields. The theory and practice offers not only a novel method to develop China offshore oil field but also new ideals for the development of global offshore oil fields, especially for the heavy oil fields.