Butler的SAGD产量计算公式错在哪里

对于厚度较大的重质油藏,尽管Butler(巴特勒)于1991年提出了双水平井上注下采的所谓SAGD(Steam-Assisted Gravity Drainage)开采原理和方法 ,得到了热力开采专家的高度重视,并进行了矿场实践,取得了很大的经济效益和工作经验。但是,Butler提出的SAGD产量计算公式,却很少看到有关实际应用的报道。究其原因,主要在于,Butler推导和建立的SAGD产量计算公式,存在3个基本的错误,因而,导致了公式应用的不正确性。这3个基本的错误是:将属于三维流动的模型误改为二维流动;将达西定律表示的稳定常数流量,误认为可变的微分流量(differential flow rate);仅考虑了地层原油的重力驱动作用,而忽视了注入与采出井底之间流动压差的驱动作用。文中对Butler的SAGD产量计算公式存在的3个基本错误进行了分析,并提出了有关的产量计算方法。     

SAGD采出液高压高频脉冲电脱水的试验研究

针对SAGD采出液乳化程度高、成分复杂的问题,该文采用高频高压脉冲方法对采出液进行试验研究,系统分析电压幅值、频率、占空比、脱水时间对脱水性能的影响规律。试验表明:电压幅值增加,聚结破乳效果提升,脱水功率随之升高,电压幅值过大时,脱水率和功率呈现降低的趋势;频率过大时,脱水率大幅降低,短路的出现使得功率大幅增长;占空比增加,极化变形程度增加,脱水率、脱水功率随之增加;占空比超过0.5,出现过度极化和电分散;2.5h以后,极化作用力显著减少,脱水率缓慢增大,3h以后呈现平稳的趋势。SAGD电脱最佳操作条件:电压幅值5.5k V,频率4k Hz,占空比0.5,时间3h。本文为特超稠油采出液的高效脱水奠定了基础。     

RMS-I型磁定位系统的研制和应用

磁场测量定位装置是蒸汽辅助重力泄油技术（SAGD）的关键设备,为了精确定位提高采集率,设计出RMS-I型磁定位系统,主要由精密磁场发生源、三轴磁场探测器、信号传输系统及地面解释计算软件组成,详细分析了各部分相关设计及原理,介绍了系统的详细性能参数,通过对该系统进行现场应用试验,结果表明,RMS-I型磁定位系统的测量精度达到国外同类仪器先进水平,为我国油田技术的高效开发提供了技术保障。     

A Novel Approach for Resolving Reverse Emulsions in SAGD Production Systems

The standard method for water clarification in SAGD operations involved the injection of latex polymers to break produced reverse emulsions. Operationally, this resulted in large quantities of oil in the water downstream of the first oil and water separation vessel. Problems occurred because this generated large amounts of oily solids and emulsion. This slop material represented a significant additional expenditure. Champion developed a novel approach to treat these systems and reduce slop. This program has been very successful in removing oil from the water stream during primary separation, thus reducing costs associated with reprocessing slop oil, and resulting in greater oil recovery.     

Robust Gaussian process modeling using EM algorithm

Gaussian process (GP) regression is a fully probabilistic method for performing non-linear regression. In a Bayesian framework, regression models can be made robust by using heavy-tailed distributions instead of using normal distribution for modeling noise. This work focuses on estimation of parameters for robust GP regression. In literature, these are learned by maximizing the approximate marginal likelihood of data. However, gradient-based optimization algorithms which are used for this purpose can be unstable or may require tuning. In this work, an EM algorithm based approach is derived and implemented to infer the parameters. The pros and cons of the two approaches are analyzed. The advantage of EM algorithm lies in its ease of implementation and theoretical guarantees of numerical stability and convergence while its prediction performance is still comparable to gradient-based approaches. In some cases EM algorithm may be slow to converge. To circumvent this issue a faster EM based approach known as Expectation Conjugate Gradient (ECG) is implemented on robust GP regression. Finally, the proposed EM approach to robust GP regression is validated using an industrial data set.     

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。     

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.     

降膜蒸发法处理超稠油SAGD采出水试验研究

介绍了加拿大在油砂开采过程中,机械压缩蒸发法处理采出水的应用进展。针对辽河油田超稠油SAGD工程蒸汽发生和采出水处理技术存在的问题和技术需求,辽河油田进行了降膜蒸发法处理超稠油SAGD采出水的室内先导试验,阐述了降膜蒸发法的主体工艺、主要设计参数、出水水质、结垢情况、试验过程药剂投加、蒸发热源的选择以及试验中存在的问题及改进措施。此外,还对超稠油SAGD开发用汽包锅炉给水标准进行了探讨。     

剩余油饱和度测试技术在水平井开发中的应用

剩余油饱和度测试具有定量评价剩余油分布的特点,对超稠油水平井开发具有突出的指导作用.对井间加密水平井测试进一步证实井间有大量剩余油存在,有效指导了二次开发部署;对生产井进行连续监测,指导调整注汽方式,改善水平井水平段动用程度,提高开发效果,并可对裸眼测试资料进行有效补充;对于SAGD开发,可依据剩余油饱和度变化情况确定转SACD时机及调整注汽参数.