关于油田注汽锅炉干度控制系统的若干思考

在油田热采稠油生产过程中,油田注气锅炉属于其关键设备,主要是利用软化水的加压和提温来蒸发成饱和的湿蒸汽,然后,采用人工输送的方式进入到井下油层中,以确保热采稠油生产中有足够的加热能量。本文主要以油田注汽锅炉蒸汽干度控制系统为例,首先指出了蒸汽干度控制系统中的技术难题,其次对油田注汽锅炉蒸汽干度控制系统进行了分析。     

电容法测量注汽井干度机理研究与电路实现

摘要针对当前油田进行热注蒸汽开采稠油时干度测量的重要性,提出一种蒸汽干度在线测量的电路设计方法,采用单片机、积分器及比较器等器件组成系统电路;利用集成的双重斜波测量传感器电容值,根据电客与湿度的关系可知蒸汽干度值,实现了蒸汽干度的在线测量,提高了测量精度。     

双涡街法测量饱和蒸汽干度研究

注汽热采是稠油油田开采的主要手段,此方法开采的效率主要取决于蒸汽干度的高低。经研究表明,在注入相同的蒸汽量的情况下,蒸汽的干度越大,采收率越大,油汽比越高。只有较高干度值的饱和蒸汽才能对稠油有很强的驱动效果。但是干度太高,会使注汽锅炉水中的盐份大量附着在炉墙壁上,致使锅炉结垢,降低锅炉的热效率,甚至危及锅炉的运行安全;干度太低,通过管道传送到井底后干度就更低了,无法有效驱动稠油层,达不到开采稠油目的。可见,对饱和蒸汽的干度值进行实时、准确测量具有重要意义。然而,现今国内外仍无工程上实用的干度仪,使其具有实时测量、准确度高、寿命长、造价低的性能,针对此问题提出了基于双涡街联合法测量湿饱和蒸汽干度的方法。     

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。     

蒸汽驱等干度分配与计量技术

辽河油田是我国最大的稠油高凝油生产基地,稠油主要采用蒸汽吞吐和蒸汽驱的开采方式。稠油热采在蒸汽吞吐末期一般转蒸汽驱开发,蒸汽驱现场往往存在一台锅炉同时向2-3口井注汽,或多台注汽锅炉为整个注汽管网供汽的现象,存在干度分配的偏差,为此提出以下一种新的等干度分配技术,保证了一台或多台注汽锅炉在同时注多口井时的注汽干度相同、注汽速度相同。     

鲁克沁油田35兆帕超临界注汽的试验与应用

目前国内21MPa亚临界压力蒸汽开采超深层稠油效果不佳,为解决鲁克沁油田超深层稠油开发难题,吐哈油田提出超临界注汽热采方案,对鲁克沁油田超深层稠油进行了35MPa超临界蒸汽吞吐先导试验,结果表明,利用超临界注汽对超深层稠油开采效果明显,为有效开采鲁克沁油田提供有利技术支撑。     

油田提高注汽锅炉蒸汽出口干度技术研究

新疆油田超稠油开发和普通稠油后期开采需要更高的蒸汽干度,而常规锅炉蒸汽出口干度只有80%,已不能满足现阶段注蒸汽开采工艺要求。为此,提出了汽水分离、过热、掺混方法进提高蒸汽干度,并使其伴有15℃过热度,达到了蒸汽驱稠油热采条件,现场应用表明该方法在节能、环保和能效上效果显著。     

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。     

三塘湖稠油区块实施超临界注汽探讨

新疆三塘湖油田稠油区块为"五低"区块,即低渗、低孔、低压、低温、低储量丰度。本文阐述了在三塘湖油田稠油区块实施超临界注汽的优点和可行性。超临界注汽时,只要在井底能保证高温高压以使水处于超临界状态而不要求有一定的蒸汽干度,超临界水就会含有足够的热焓以加热油藏原油。三塘湖油田稠油区块可以建立起超临界条件,现有设施也可以满足超临界条件的建立。     

海上稠油热采注汽锅炉的选择建议

热力开采是稠油油田开发的有效手段,但相关技术在海上稠油开采中尚不成熟。注汽锅炉是稠油热采工艺实施过程中的核心设备。本文从海上稠油油田的实际操作条件出发,对海上稠油热采工艺的注汽锅炉型式、排量、蒸汽品质的确定提出建议。海洋平台条件下,选择立式锅炉更合适,且三回程比单回程优势更明显;人工岛条件下,选择卧式锅炉则更适宜。无论海上平台或人工岛条件,注汽锅炉的理想排量为50 t/h。综合考虑水源特点及热采效果,海上稠油热采工艺宜采用过热蒸汽。     

稠油降粘技术在采油工艺上的应用

针对高粘稠油开采中的一些实际问题，开发研制了CJ-128稠油油溶性降粘剂。通过管流实验的测定，对比分析了该降粘剂的降粘效果，实验结果表明，随着添加CJ-128降粘剂比例增大，降粘幅度也加大。同时，随着稠油含水率加大，其降粘幅度减小。用CJ-128稠油降粘剂采油，井下油温不低于50℃时，每采1吨油，只需加入5％即50kg的降粘剂。由于降粘剂与稠油互溶，所加入5％的降粘剂与稠油一起可全部采出地面，一方面可直接增加5％的采油产量，另一方面降低了采油成本。     

考虑储层非均质时注汽井内蒸汽流动规律

稠油热采水平井注蒸汽是一个复杂多变的过程，水平井沿程蒸汽热物性的预测对于储层的均匀动用十分关键。考虑储层渗透率、围压和蒸汽相变等条件的相互耦合影响，建立了预测水平井注汽流动的综合数学模型。与现场测井数据进行对比分析，验证了模型的准确度。模拟结果表明，单一变量条件下，水平井跟部注汽压力越大，注汽井内质量流量和蒸汽干度下降越快，当注汽压力由11 MPa降为8.5 MPa时，配汽距离增加1倍；在水平井相同位置处，跟部注汽干度越高，注汽井内质量流量越大，且蒸汽压力下降越快，注汽干度提高1倍时，压降也几乎增加1倍；跟部注汽流量越大，蒸汽压力下降越快，注汽流量提高1.75倍时压降提高了5.3倍，但管内蒸汽干度下降趋缓；储层渗透率越高，注汽井内的蒸汽干度下降越快。该模型可以为现场注汽提供理论支撑，有效提高配汽效果达到增产降耗。     

Steam flow law in horizontal wells when considering reservoir heterogeneity

Steam injection in horizontal wells for thermal recovery of heavy oil is a complex and changeable process. The prediction of thermal properties of steam along horizontal wells is critical to the uniform production of reservoirs. In this paper, considering the mutual coupling effects of reservoir permeability, confining pressure, and steam phase transition, a comprehensive mathematical model for predicting steam injection flow in horizontal wells was established. Compared with the on-site logging data, the accuracy of the model was verified. The simulation results show that under a single variable condition, the larger the steam injection pressure at the heel, the faster the mass flow and steam dryness decrease. When the steam injection pressure drops from 11 MPa to 8.5 MPa, the steam distribution distance doubles. At the same position, the higher the steam dryness at the heel, the greater the mass flow in the steam injection well, and the faster the steam pressure decrease. Double the steam injection dryness, the pressure drop is almost doubled, but the longer steam injection distance. The larger the steam injection flow at the heel, the faster the steam pressure decreases, and the decrease in the steam dryness in the tube slows down. When the steam injection flow increases by 1.75 times, the pressure drop increases by 5.3 times. The higher the reservoir permeability, the faster the steam dryness decreases. By obtaining the general rules of steam distribution in horizontal wells to provide theoretical support for on-site steam injection, the steam distribution effect can be effectively improved to increase production and reduce consumption.     

润滑油市场：外商在华拓展业务的机遇和前景

我国是第三大润滑油生产国和消费国。面对中国的广阔市场,西方石油公司凭借技术成熟、经验丰富,纷纷在华建润滑油生产厂,其中美国公司已捷足先登:美孚、埃克森、壳牌等分别在我国建立了独资或合资润滑油生产厂,其它西方国家公司有:埃尔夫、Jomo、东方石油公司、Sunoil、加拿大热润滑油公司等。这些公司在华已投产和将投产的润滑油调合厂建成后,产品将占我国市场的20％以上。车用润滑油竞争激烈,船用润滑油、航煤方面外商市场份额将扩大。另外通过自行开发与对外合作相结合,我国石油添加剂生产技术也将有较大幅度的提高。在我国润滑油生产立足国内、扩大开放的形势下,外商也将会有更多的商机。     

高温反相破乳增效剂的研究与应用

曙光油田处于开发的中后期,高周期油井多.要提高超稠油、稠油注汽生产效果必须解决蒸汽冷凝水和稠油乳化、原油中的重质成分在岩石表面沉积、稠油降粘等问题.在注汽开采的中后期使用一定的化学处理剂,破坏稠油与水形成油包水乳状液,剥离岩石表面的油膜,降低地层流体的粘度,从而提高原油的流动性,增大油层渗透率,达到增加原油产量,提高回采水率的目的.高温反相破乳增效剂,是针对上述问题而研制的一种复合化学药剂.该药剂在现场应用效果明显,具有较大的推广使用价值.     

基于Fluent的井下油水分离和润滑过程中新型润滑元件设计分析

为解决含水稠油采输时油水分离和降黏减阻的问题,采用Fluent软件对井下油水分离和润滑过程进行数值模拟,并设计出一种新型的润滑元件,使其能就地安装,形成高质量油水环状流,有效控制采出液的含水率,提高含水稠油井采收率,并降低后续原油处理成本。固定入口流速为0.6m/s,分流比为0.5,进行润滑元件结构的单因素分析。结果表明：流体在溢流口处径向速度极小,说明形成的油核几乎不存在偏心现象,轴向速度的存在有利于形成清晰的油水界面,从而利于形成高质量的油水环状流,经过元件的流体分离出部分水后轴向速度也得到了提升,有利于提高原油采收率。进行与仿真模拟相同工况下的室内实验,通过改变流速观察润滑元件的压降值与流型的变化情况。结果表明：合理的入口流速范围内,采用雷诺应力模型（RSM）与混合多相流模型（Mixture）计算模拟润滑元件内部流场情况具有较高的可信度。     

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.     

尿素脱蜡装置的设计与生产运行

介绍了沈阳石蜡化工有限公司６．０Ｍｔ/ａ尿素脱蜡装置的设计、生产运行及生产中存在的问题。生产运行表明,采用大庆原油的常二线馏分油生产３００＃重液蜡和－３５＃低凝柴油,产品质量均达到行业及国家标准,综合能耗也低于原设计。     

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.