直井-水平井组合多介质辅助重力泄油实验研究

利用比例物理模拟技术,开展了直井-水平井组合多介质辅助重力泄油物理模拟实验。研究了多介质辅助重力泄油蒸汽腔的形成和发育特点、开采机理及生产特征,优选了注采参数,预测了开发效果,为现场实施及开发方案编制提供借鉴。     

蒸汽吞吐后期转蒸汽辅助重力泄油数模研究

针对小洼油田洼38块下第三系沙三段深层、特稠油油藏的特点及目前蒸汽吞吐开发进入尾声的现状,利用热采数模软件,对蒸汽吞吐后转蒸汽辅助重力泄油(简称SAGD)开发方式主要油藏工程参数如:生产层位、SAGD组合形式、直井与水平井水平距离、直井与水平井垂直距离、注汽直井井数、注入参数、水平井排液量进行了数模研究,并得出了结论。     

蒸汽辅助重力驱产量预测

蒸汽辅助重力驱（SAGD）是水平井结合注蒸汽开采稠油的一种较为新颖的开采方式。针对目前蒸汽辅助重力驱的研究现状,在前人研究的基础上,进行SAGD生产的产量动态预测,将其结果与现场数据进行对比。探讨超稠油油藏蒸汽辅助重力泄油的渗流机理和渗流规律,从而为油田进行蒸汽辅助重力泄油的开发提供理论依据。     

双水平井SAGD循环预热阶段优化研究

SAGD（蒸汽辅助重力泄油）技术是开发超稠油的一项前沿技术。SAGD的启动阶段对SAGD生产过程有重要的影响。蒸汽循环预热启动吸汽加热均匀，启动平稳。通过数值模拟方法，对SAGD启动阶段的油管隔热性能，储层渗透率，储层垂直水平渗透率比以及隔层对预热效果的影响进行了优化研究，分析了这些参数对SAGD启动阶段的影响。     

基于模糊综合评价的烟道气辅助SAGD过程评价

目前烟道气辅助蒸汽辅助重力泄油（SAGD）技术已在机理研究和数值模拟方面取得了进展,但由于实际投入油田试验的操作成本较高以及存在额外的能量消耗,所以无法直接判断和验证实际应用效果。为了更全面地评估注采方案,本文运用模糊综合评价法建立了多元评价体系,以环境、能量、工艺、经济为4个评价指标,对不同注采方案进行综合评价以选出综合性能最优的生产设计方案,为实际生产方案的选取提供参考,首次对烟道气辅助SAGD实际工程进行评价研究。基于“有无对比法”,将烟道气辅助SAGD与常规SAGD进行对比,结果表明烟道气辅助SAGD的综合效益更好,佐证了烟道气辅助SAGD驱油的优越性。为方便工程应用,开发了“烟气辅助SAGD驱油评价软件”,通过软件进行实例分析并进行方法对比,验证了本文方法的有效性、适用性和准确性。     

TWBS软件结合CMG数值模拟优化双水平井SAGD循环预热参数

SAGD循环预热效果是影响SAGD开发的关键因素之一,它决定着井组热连通效果及蒸汽腔的初始发育状态,关系到SAGD生产阶段调控难度和最终采收率。由于SAGD循环预热阶段管柱结构复杂,应用常规的数值模拟方法进行预热参数优化困难。本课题通过引进TWBS软件辅助CMG数值模拟,反映了现场实际循环预热的管柱结构,对循环预热阶段注采参数进行了优化设计,得到了合理的循环预热参数,为下一步SAGD顺利实施提供了可靠的依据。     

杜84馆陶西SAGD开发认识及动态调控

蒸汽辅助重力泄油(SAGD)技术以蒸汽作为热源,依靠凝析液的重力作用开采稠油,采收率可达60%-80%。通过对杜84馆陶西6个直井和水平井井组转入SAGD开发的认识,寻找出开发中存在的不足及问题,摸索动态调控办法,提高开发效果。     

SAGD技术在国内的研究与发展

蒸汽辅助重力驱油(简称SAGD)技术,逐渐在稠油油藏开发中得到应用,随钻井技术不断发展,借助双水平井或直井水平井配合采油也得到了推广。本文基于不同布井方式,对SAGD技术在国内的发展进行了概述,结合油藏方法和数值模拟研究,得到一些认识。     

新型SAGD技术在稠油开采中的应用

石油业是国家经济发展中的关键产业,近些年,国家进一步提高了对油田开采的关注程度与扶持力度,这促使国内的油田开采活动得到了明显的进展。稠油属于一种有机混合物,少数油田中稠油油藏因油质黏度大、性质劣、密度大等问题,在开采过程中难度非常大,再加上近些年稠油热采区块的日益减少,采油数量不断降低,所以,目前急需深入研究稠油开采技术,而蒸汽辅助重力泄油法(SAGD)就是一种新的稠油开采方法。基于此,文章详细分析了蒸汽辅助重力泄油法的类型:双井SAGD方法、单井-直井SAGD方法、直井-水平井SAGD方法、迅速SAGD方法,并详细阐述了稠油开采中SAGD方法的使用。     

SAGD蒸汽腔三维物理模拟装置设计

针对现有与热力采油相关的物理模拟装置模型热损失大、装置耐压性能差和功能单一等一系列问题,参考现有的比例物理模拟实验装置,成功研制出了新型多功能可视化三维物理模拟模型。该装置针对现有热采物理模拟装置模型的弊端,该装置重点解决了以下几个难题并形成了特色技术:(1)增强油藏比例厚度,准确模拟非均质油藏;(2)在模拟过程可视化,实时监测与调控油藏动态;(3)增强保温能力,降低热损,提高热利用率,模拟结果准确化;(4)实验模拟多功能化:双水平井SAGD(蒸汽辅助重力泄油)、直井注蒸汽辅助水平井采油、蒸汽吞吐、VAPEX采油。该装置投入使用后,可以较好地模拟稠油热采特别是SAGD采油的生产动态,监控蒸汽腔发育情况,深化对稠油热采的机理和生产动态规律的认识,更好的指导稠油油藏的开发。     

重18井区八道湾组超稠油油藏水平井开发效果影响因素分析

水平井蒸汽吞吐开采超稠油是一项非常有潜力、有优势的技术,相比直井开发,不仅能大幅度提高开发效果,而且能够进一步提高采收率。研究稠油油藏水平井蒸汽吞吐开发效果,分析地质参数及注汽参数对该类油藏开发效果的影响程度,并进行灰色关联分析。研究表明对周期产油量影响最大的因素是采注比,其次是原油粘度。     

Stability of the edge of a SAGD steam chamber in a bitumen reservoir

Steam-Assisted Gravity Drainage (SAGD) is a key in-situ recovery process being used today to extract oil from bitumen reservoirs. In SAGD, an oil-depleted chamber of steam grows within the oil sands formation along a pair of horizontal wells and heats bitumen-laden oil sands at its edge. The viscosity of bitumen drops by up to five orders of magnitude when heated to above 200 °C and mobilized bitumen at the chamber edge flows under gravity to a production well located at the base of the chamber. If the steam chamber does not grow uniformly along the wellpair, then bitumen recovery is less than ideal. To raise the thermal efficiency, and consequently the economics, of the process, efficient heat transfer from chamber to the oil sands must occur and the chamber must grow uniformly along the entire length of the wellpair. If steam fingers develop at the edge of the chamber, then the heat transfer area enlarges and raises the thermal efficiency of the process since more heat is directed to the oil sands. In this research, the stability of the interface between the steam chamber and oil sands is examined by using linear stability theory. The results show that the stability is controlled by the difference between the energy content-weighted Darcy–Rayleigh numbers of the steam/water phases (displacing fluid) and the oil phase (displaced fluid). Also, the results show that at typical SAGD steam saturation temperatures, the chamber edge is unstable providing the steam quality at the edge exceeds about 50%.     

Multiphase flow at the edge of a steam chamber

The use of steam‐assisted gravity drainage (SAGD) to recover bitumen from Athabasca deposits in Alberta has been growing. Butler [Butler, J. Can. Pet. Tech. 1985;24:42–51] derived a simple theory to calculate the production rate of oil during SAGD in an ideal reservoir. This simple and useful theory made several assumptions about the properties of the reservoir and operating conditions of the process. The theory also assumed that the highest mobility oil is at the edge of the steam chamber and that the oil phase velocity is highest at the chamber edge and reduces with distance into the oil sand. This research examines flow conditions at the edge of the steam chamber. Specifically, a new theory is derived that takes into account the impact of oil saturation and relative permeability on the oil mobility profile at the edge of a steam chamber. It is shown that the flow behaviour at the edge of a steam chamber is more complex and is not fully represented by Butler's theory. Contrary to Butler's theory, the oil mobility has its maximum some distance away from the edge of the steam chamber. The results reveal that the higher the thermal diffusivity of the oil sand, the deeper the location where the oil phase velocity is maximum. The developed model has been validated against published experimental and field data.     

薄层稠油油藏SAGD物理模拟研究

紧密围绕杜84块兴Ⅰ组油藏的地质特点与开发现状,依据相似原理设计建立了比例物理模型,开展SAGD比例物理模拟实验,探讨了薄层稠油双水平井SAGD开采中蒸汽腔的形成和发育过程,生产特征和开发效果,预测了盖层的热损失,可为开发方案编制提供借鉴。     

稠油蒸汽吞吐后期增产技术现状与前景

目前,国内外许多油藏已处于蒸汽吞吐的后期。此时的油藏油气比低、含水量高、地层压力低、井况差、周期注气量大、操作成本高,产油更加困难。改善蒸汽吞吐后期的采油技术,可以最大限度的提高油藏的采收率。如今,应用于蒸汽吞吐后期增产的方法有:应用助剂改善吞吐效果、间歇注汽技术、"一注多采"技术、多井整体吞吐技术、注采参数优化技术、侧钻水平井技术、蒸汽驱技术、蒸汽辅助重力泄油技术和火烧油层技术等。然而,现在我国还在尝试发展一些新的技术,如水平压裂辅助蒸汽驱和多井组整体优化蒸汽驱等等。这使得蒸汽吞吐后期的增产技术拥有更为广阔的前景。     

Integration of machine learning and data analysis for the SAGD production performance with infill wells

There have been numerous studies on predicting the production performance of the steam assisted gravity drainage (SAGD) process by data-driven models with different machine learning algorithms since their introduction into industry. Similar efforts on SAGD infill wells, nevertheless, remain rare for this advanced alteration in improving the classical SAGD performance. On the other hand, predictive tools to optimize an infill well start time is useful in maximizing bitumen production and minimizing its costs. In this paper, a series of SAGD infill well models are constructed with selected ranges of operational conditions. Three SAGD infill well production performance indicators, namely, an increased ratio ($R_{\text{increase}}$), a total steam–oil ratio (SOR_total), and a stolen ratio ($R_{\text{Stolen}}$) for each SAGD infill well, are calculated based on simulated infill well cases and control models. Five different machine learning algorithms (an artificial neural network [ANN] algorithm, three gradient boosting decision tree [GBDT] algorithms, and a support vector machine [SVM] algorithm) are trained, tested, and evaluated for their effectiveness in predicting those three indicators as output parameters, given seven SAGD relevant parameters as input parameters. Comparisons of different data sets show that the ANN is the best in predicting all three performance indicators under different infill well start times among all the above machine learning algorithms, while the GBDT algorithms have a better ability to learn a variation trend in the SAGD infill well performance.     

M稠油油藏注采参数优化数值模拟研究

针对哈萨克斯坦M稠油油藏的开发现状,利用测井、地质资料,建立了能够反映当前勘探开发特征的三维地质模型,以此为基础利用数值模拟方法进行了剩余油分布规律研究;分析了注汽速度、注汽温度、注汽干度、汽驱方式、注采井网等因素对开发效果的影响,并优选出最佳注采参数,为M油田中区的高效开发提供一定的理论参考和借鉴。     

Heavy oil recovery efficiency using SAGD,SAGD with propane co-injection and STRIP-SAGD

Primary oil recovery methods in heavy oil basins generally extract 5–10% of the available resource, with the vast majority left in the ground and recoverable only through Enhanced Oil Recovery (EOR) methods. Traditional EOR methods, such as SAGD and solvent-assisted SAGD, generate steam in surface facilities and inject it underground to mobilize the oil for production. However, these methods can have considerable energy losses that significantly impact process performance. In contrast, the Solvent Thermal Resource Innovation Process (STRIP) technology, which uses down hole combustion of methane to produce CO₂ and steam, reduces the operating and capital costs of surface facilities, saving more than 50% of the energy typically required for thermal production. In this work, simulations of conventional SAGD, SAGD with a non-condensing solvent (propane), and STRIP-SAGD for a typical bitumen reservoir in the Fort McMurray region in Alberta, Canada were performed using the combined software system ADGPRS/GFLASH. SAGD simulations used steam injection with a quality of 0.8 while STRIP simulations injected a vapor–liquid mixture with a quality of 0.8. Furthermore, both solvent-based EOR methods required longer operation periods than conventional SAGD to recover a similar amount of oil. However, when compared on the basis of cumulative oil produced for the same overall energy input, it is shown that STRIP-SAGD recovered more oil per kJ of energy input to the reservoir than either SAGD or SAGD with propane co-injection.     

Steam fingering at the edge of a steam chamber in a heavy oil reservoir

The steam‐assisted gravity drainage (SAGD) process is one of the key in situ recovery processes being used today to recover heavy oil and bitumen. In this process, steam injected through a horizontal well, flows convectively towards the outer edges of a depletion chamber. At the edges of the depletion chamber, the steam releases its latent heat to the cool oil sand and raises its temperature. The heated oil is mobile and flows under the action of gravity to a horizontal production well located several metres below the injection well. It remains unclear what is the exact mechanism of chamber growth. Some have suggested that in addition to heat conduction, it is by convective steam flow in the form of pointed fingers at the edges of the chamber which penetrate the oil sand. In theory published by Butler [Butler, J. Can. Petroleum Technol. 1987;26(3):70–75], it was determined that the fingers can be as long as 6 m for Athabasca bitumen reservoirs. In this research, a new theory is derived and provides predictions of the rise rate which compare better to estimates derived from field thermocouple data and physical model experimental observations than values obtained from Butler's theory. The results suggest that in the absence of mobile water, heat conduction rather than steam fingers at the chamber edge is the dominant heat transfer mechanism.     

杜229块蒸汽驱扩大试验参数优化设计

鉴于杜229块蒸汽驱先导试验较好的开发效果,进行蒸汽驱的扩大试验,为该块规模汽驱作准备。方案设计中在分析先导试验效果的基础上,利用数值模拟方法优化扩大试验的主要注采参数,最大限度地提高蒸汽驱的开发效果和经济效益。