海上稠油油藏水平井注蒸汽开发技术研究

为提高海上稠油油藏水平井注蒸汽开发效果,以渤海某油田明化镇组稠油油藏为实例,首兇分析了该稠油油藏注入蒸汽开采的经济和技术可行性,明确了该稠油油藏具有良好的注汽开发前景,通过油藏数值模拟方法,分别模拟了注蒸汽速度、关井时间、井底蒸汽干度、蒸汽温度和采液速度对周期内注汽开发效果的影响。结果表明:最佳注蒸汽参数设定为注蒸汽速度350 m~3/d、关井时间6 d、井底蒸汽干度0.8、蒸汽温度370℃、采液速度150 m~3/d,同时为迚一步提高注蒸汽开发效果,在设备条件允许的情况下,尽可能地提高注入蒸汽的温度来达到更好的注采效果。     

稠油油藏注蒸汽开采方法研究

随着石油资源不断的减少,容易开采的原油油藏不断的减少,难采油藏储层所占的比例越来越高。我国有着广泛的稠油油藏资源,稠油资源分布广、储量非常可观。一些稠油油藏的埋藏较深,常规的开采方法难以实现稠油油藏的高效开发,注蒸汽开发的方式可以有效的提高稠油油藏的开发效率。目前稠油油藏的注蒸汽开发技术的研究还不全面和深入,因此开展稠油油藏注蒸汽开发技术,对于提高稠油油藏的开发效率具有重要的意义。文章研究了稠油油藏注蒸汽开采的机理,并且对比分析直井衰竭式、注热水、注蒸汽种三种方式的开发效果。通过研究对于提高稠油油藏的开发效率具有重要的意义。     

稠油注蒸汽开采提干提效配套技术的开发

稠油油藏注蒸汽开发的复杂性主要体现在如何充分利用热能,而蒸汽干度是影响蒸汽热能利用效率的首要因素,是衡量蒸汽质量的重要指标。通过分析河南油田稠油注蒸汽开采在制汽系统、输汽系统、注入系统以及监测系统各个环节存在问题,进行提干提效技术研究,配套了地面高干注汽工艺、井筒全程保干技术、高效注汽工艺、以及热采井动态监测技术,通过加强地面和井筒一体化配套,从而保障热需求、控制热损失,从而提高蒸汽干度、提高热能利用效率,对改善稠油开发效果,提高稠油热采效益具有重要意义。     

蒸汽吞吐主要参数对开发效果影响研究

在普通稠油油藏开发过程中,蒸汽吞吐通过注蒸汽、焖井、开井生产三个阶段可以降低原油粘度,改善流度比,从而降低残余油饱和度,提高驱替效率,是一项有效的开采稠油的方式。蒸汽吞吐的开发效果是热采参数综合作用的结果。本文通过数值模拟的方式,系统的研究了注汽强度、注汽速度、焖井时间、排液时间对开发效果的影响,对普通稠油油藏开发具有提供相应的参考     

稠油蒸汽吞吐阶段采收率计算方法综述

本文针对稠油蒸汽吞吐阶段采收率计算的基本原理和适用条件,对稠油油藏蒸汽吞吐开发条件下确定采收率的类比法、多元回归法、注采特征曲线法、增长曲线法、递减曲线法、粘温曲线法、数值模拟法等方法进行了归类对比分析,形成了稠油油藏蒸汽吞吐阶段原油采收率确定方法系列,指出目前较为常用的原油采收率计算方法,得到了计算效果较好的原油采收率计算方法。     

注蒸汽开采稠油油藏提高开发效果研究

石油资源的储存量固定,而需求量在不断增加,较容易开采的油藏在逐渐地减少。为了更好地满足人们对石油的需求,必须提高石油开采技术,对较难开采的油藏层进行探索,找到比较有效且实用的开采方法。在中国,稠油油藏资源比较丰富,但是地形也比较复杂,以前的开采技术难以有效地将油藏较深的稠油开采出来,而注蒸汽技术的引入,大大提高了稠油油藏的开发效果。本文将着重阐述注蒸汽技术在稠油油藏开采方面的应用,以及在提高开发效率方面的研究成果。     

潜山稠油油藏开发方式优化研究

郑家油田郑6块沙一段为典型的潜山稠油油藏,该油藏满足稠油热采标准,适合注蒸汽吞吐开发。文章在分析该块试采特征的基础上,结合该块地质特点,选择直井注蒸汽吞吐的开发方式,并通过数值模拟手段,优化了蒸汽吞吐井距、避射厚度、注汽强度、吞吐转蒸汽驱时机等参数。     

稠油水平井蒸汽吞吐开发实践

本文介绍了薄层稠油油藏水平井注汽参数设计思路,主要是应用油藏工程方法、经验法及数值模拟法相结合,结合区块内直井蒸汽吞吐注汽参数,分别优化确定水平井注汽强度、注汽速度、焖井时间等注汽参数,工艺上采取水平井段均匀注汽设计,现场应用证明,水平井开发薄层稠油具有很大优势。     

影响超稠油蒸汽吞吐开发效果因素分析

蒸汽吞吐技术由于其适用条件广,经济效益高是目前开发稠油热采技术中应用最广泛技术。影响稠油热采开发效果因素众多,本文主要从油藏地质条件,注汽工艺参数,射孔条件三个主要面分别阐述其对超稠油蒸汽吞吐开发效果影响。     

薄互层稠油油藏火驱开发研究与应用

火驱技术是稠油油藏蒸汽吞吐后大幅度提高采收率技术之一。国外已经开展了浅层单层火驱的工业化应用,并取得了很好的开发效果。对于薄互层状稠油油藏,采用单层火驱单井产量低、采油速度低,开发效果差。针对此问题,本文应用数模、油藏工程计算等方法开展了薄互层稠油油藏火驱技术研究,对井网形式、燃烧方式、注采参数进行了优化设计,并评价了先导试验效果,认识火线推进规律,该研究对同类油藏的火驱开发具有一定的借鉴作用。     

薄层稠油油藏水平井分段蒸汽驱筛选研究

针对小断块或井场开采条件受限的薄层稠油油藏,提出水平井分段蒸汽驱的开发方式。因蒸汽驱对油藏条件要求高,故投产前须进行筛选。根据不同原油粘度和油层厚度的组合模拟计算结果,研究原油粘度和油层厚度对稠油油藏水平井分段注采开发效果的影响,建立筛选评价标准。研究结果表明,当油层有效厚度超过7.2m时,可利用水平井分段蒸汽驱经济开采原油粘度低于5000mPa.s的普通稠油油藏;油层有效厚度达9.6m时,该技术可用于开采原油粘度低于20000mPa.s的稠油油藏。     

Reducing heavy oil carbon footprint and enhancing production through CO2 injection

The world's dependence on heavy oil production is on the rise as the existing conventional oil reservoirs mature and their production decline. Compared to conventional oil, heavy oil is much more viscous and hence its production is much more difficult. Various thermal methods and particularly steam injection are applied in the field to heat up the oil and to help with its flow and production. However, the thermal recovery methods are very energy intensive with significant negative environmental impact including the production of large quantities of CO₂. Alternative non-thermal recovery methods are therefore needed to allow heavy oil production by more environmentally acceptable methods. Injection of CO₂ in heavy oil reservoirs increases oil recovery while eliminating negative impacts of thermal methods.In this paper we present the results of a series of micromodel and coreflood experiments carried out to investigate the performance of CO₂ injection in an extra-heavy crude oil as a method for enhancing heavy oil recovery and at the same time storing CO₂. We reveal the pore-scale interactions of CO₂-heavy oil-water and quantify the volume of CO₂ which can be stored in these reservoirs.The results demonstrate that CO₂ injection can provide an effective and environmentally friendly alternative method for heavy oil recovery. CO₂ injection can be used independently or in conjunction with thermal recovery methods to reduce their carbon footprint by injecting the CO₂ generated during steam generation in the reservoirs rather than releasing it in the atmosphere.     

FIVE-SPOT INJECTION/PRODUCTION WELL LOCATION DESIGN BASED ON FRACTURE GEOMETRICAL CHARACTERISTICS IN HEAVY OIL FRACTURED RESERVOIRS DURING MISCIBLE DISPLACEMENT: AN EXPERIMENTAL APPROACH

Mapping fracture characteristics by using seismic acquisition and processing is important not only to identify sweet spots, but also to optimize production, especially for unconventional heavy oil reservoirs. In this experimental work we used five-spot micromodels initially saturated with heavy oil to find the optimum well locations during first-contact miscible displacement. The experiments were performed at a fixed injection rate on fractured micromodels with various patterns. The optimum location for injection/production wells was found in the pattern where fractures make an angle of 45° with the mean flow direction. Moreover, oil recovery was increased with the density, length, level of scattering, and discontinuity of fractures. The analysis of the experimentally measured recovery curve revealed that there are three distinct stages for each displacement. The efficiency of the first stage was found to be dominated by dispersion and diffusion. However, the recovery of the second stage was significantly affected by the fracture orientation. The displacement efficiency of the third stage was controlled by solvent dispersion, which is at maximum for the pattern with higher density, length, scattering, and discontinuity of fractures. Saturation monitoring showed that the fracture geometrical characteristics strongly affected the splitting, spreading, and shielding of the produced fingers and solvent front shape and consequently affected the recovery factor. As a result, five-spot micromodels can be used to investigate the optimum location of injection/production wells during miscible displacements in fractured heavy oil reservoirs.     

Estimation of thermal maturity status of petroleum asphaltenes and maltenes

Asphaltenes from various bituminous sand, heavy oil and conventional oil reservoirs and maltenes from various conventional oil reservoirs have been pyrolysed at 130 °C (for the asphaltenes), and at 50 °C (for the maltenes) in the presence of hydrated aluminium chloride crystals as catalyst for the decomposition. The rates of production of gases were appreciable and measurable. Asphaltenes from bituminous sands from the same geographical location showed a clear correlation between the rate of gas production and the depth of burial. The trend indicates that the thermal maturity of the oil increases with increase in the depth of burial. For conventional oils, a correlation was also observed between the rate of the gaseous product yields and the geological age. Maltenes from the conventional oils gave similar results: here the trend indicates that the thermal maturity of the oils increases with increase in geological age. From the derived correlation curve, the geological age of unknown crude oil was determined (525 × 10⁶ years: middle Ordovician age).     

胜利油田稠油热采开发技术研究进展

针对胜利油田稠油油藏地质特点及开发难点,重点介绍了中深层特超稠油油藏、浅薄层超稠油油藏、敏感性稠油油藏和低渗透稠油油藏等复杂稠油油藏的开发技术,并对其提高采收率机理和现场应用效果进行了总结概括。在此基础上,根据目前研究进展指出了稠油热采开发技术的发展方向,重点介绍了超深层低渗稠油和浅薄层特超稠油的开发技术及其应用。     

Heavy oil refining and transportation: effect on the feasibility of increasing domestic heavy oil production

As part of a programme to assess the feasibility of increasing domestic heavy oil production from US reservoirs, a study of the crude oil transportation system and petroleum refining industry has been initiated to determine their ability to accommodate additional domestic heavy oil. This paper summarizes refining trends and potential limitations in the production/transportation/refining network that may influence the expansion of domestic heavy oil production outside the current heavy oil producing areas. Although the number of refineries has decreased over the past decade, the remaining large refineries have been able to stabilize charge capacity and increase refinery throughput. A few refineries have been designed to economically process select heavy oils and obtain acceptable yields of products. However, refiners seek more light sweet crude oil and less sour or heavy crude to meet the requirements of clean fuels as mandated by the Clean Air Act Amendments of 1990. Transport of heavy oil poses significant problems in that there are limited heated pipelines, and transport of heavy oil to distant refineries adds to the cost of heavy oil production. Addition of significantly more heavy oil, either domestic or imported, will substantially reduce refinery efficiency and throughput affecting yields and margins. This will not change without significant investment in refinery modification to be able to process heavy oil.     

Cold heavy oil production with sand simulation including wormhole propagation and foamy oil behaviour

Cold heavy oil production with sand (CHOPS) is a primary production method used for heavy oil reservoirs with no requirements of external energy consumption. A new model for CHOPS is simulated by incorporating wormhole propagation and foamy oil behaviour mechanisms to evaluate the recovery of an extra-heavy oil reservoir of the Athabasca region. The most critical mechanisms of CHOPS, wormhole propagation and foamy oil behaviour, are captured by using Wang's model for wormhole propagation and Uddin's model of gas exsolution. After 120 months of simulation, 53.38%, 99.76%, and 100% of wormhole propagation were achieved during three time steps of 12, 48, and 60 months, respectively, toward the sides of the studied reservoir section. The propagation was achieved within all directions of the investigated section compatible with the erratic nature of wormhole propagation. Furthermore, the application of Uddin's model was incorporated into production by reducing the fluid viscosity as a result of the foamy oil behaviour. Over 3% of the recovery was achieved at the end of the primary CHOPS phase simulation by taking into account that we modelled the recovery based on highly viscous oil with API 7.5. Finally, the model can provide an improved understanding of the primary CHOPS process by considering its two significant mechanisms.     

注水开发油藏生产递减预测分析

油气藏生产递减曲线和水驱特征曲线的研究与分析,是研究油气藏极为广泛应用的一种方法.自1945年Arps总结出经典生产递减规律以来,人们一直在深入研究生产递减的各种规律,并取得了一定的成果,但是相关领域人士仍希望通过一种相对直观、简便的方法来对油田产量和最终采收率进行预测.文章结合国内外研究成果,针对注水开发油藏的特性,给出了相关生产递减分析的基本过程和步骤.最后应用该方法对实际油井进行产能预测,预测结果与现场生产数据吻合较好,验证了该产能分析方法的正确性.     

注蒸汽热采技术研究进展

在研究大量文献的基础上,总结了注蒸汽采油的机理,概述了稠油注蒸汽热采的研究现状与发展趋势,着重探讨了稀油注蒸汽热采的应用前景、研究现状以及稀油注蒸汽热采还需要深入研究的课题。研究认为：稠油注蒸汽热采已是比较成熟的技术,在稠油开发中占有重要的地位,其发展趋势为利用天然气、溶剂、高温泡沫、聚合物等来改善注蒸汽热采效果;稀油油藏水驱、聚驱后转注蒸汽热采具有可行性,今后需重点解决的问题包括采用煤或核能生产蒸汽、采用水汽交注、蒸汽泡沫等方法提高稀油油藏注蒸汽热采的采收率。     

不同类型油藏水平井部署及配套技术研究

针对厚层特稠油油藏汽驱井组蒸汽超覆严重、厚层底水普通稠油油藏底水快速突进、薄层边水特稠油油藏油水关系复杂、薄层特稠油油藏边部储量难以有效动用、火山岩裂缝性底水稀油油藏底水突进严重5类不同类型油藏中存在的开发矛盾,以精细地质研究为基础,以水平井技术为依托开展对老油田挖潜。共部署了71口水平井,实施55口,取得了良好的开发效果和可观的经济效益,增加地质储量326.66×104t,预计提高采收率7%以上,为老油田＂二次开发、深度开发、多元开发＂开辟了一条新路。