凝析天然气海管旁通清管技术

针对凝析天然气海管清管段塞影响油气田正常生产的问题,介绍了常用的解决方法,重点研究了旁通清管技术。以乐东22-1气田海底登陆管道为例,利用当前国际上先进的OLGA瞬态流动模拟软件,对旁通清管器在凝析天然气管道中的运动过程进行模拟,研究旁通清管器不同于常规清管器的运动特性、压力和流量等关键参数的变化规律以及旁通清管对清管段塞的抑制效果,以期为今后旁通清管器在凝析天然气海管中的现场应用提供理论指导。     

海底长距离湿气管线清管流动规律及方案优化

针对长距离湿气管线清管时出现的清管器速度过快、管线出口液体峰值过高、提高输量造成能耗增加等问题,基于OLGA软件建立长距离湿气管线清管模型,研究不同输量对水力清管管线入口压力、积液量的影响,研究不同输量下清管器作业时管线入口压力、清管器速度、管线出口累积液量变化规律。研究结果表明：在水力清管时,输量提升越多管线内积液量越低,但超过一定范围输量提升对积液量影响不明显;在清管器清管时,输量越大,管线入口压力振荡越小,清管器平均速度越高,管线出口瞬时液量峰值也越小。针对某气田进行清管瞬态模拟,结果表明,水力清管作业时将20万m3输量上调至28万m3、清管器清管作业时将输量下调至42万m3清管效果最佳。     

湿天然气管道积液处理方案设计与分析

积液得到必要的处理是湿天然气集气管道日常运行管理中面临的重要任务之一。为了减少集气管道中积液带来的影响和危害,基于OLGA软件的清管工艺瞬态仿真方法,建立了积液在湿气管道中的发展过程预测模型,开展了湿气管道积液沉积以及发展规律分析,在此基础上进行了湿气管道积液处理方案设计和模拟仿真,对所设计积液处理方案的有效性进行了评估。指出在集气管道间增设分离装置可以明显降低集气管道中的积液量和延长管道积液发展直至稳定的持续时间,为减小管道清管频次以及优化末端处理装置容积提供参考;在同等输量以及管道末端压力约束不变条件下,管间增设分离装置可以有效降低管道起点的动力需求,有利于整体工艺流程的节能降耗。     

Experimental Investigation and Numerical Simulation of Two-Phase Flow in a Large-Diameter Horizontal Flow Line Vertical Riser

Abstract

As oil and gas field development moves further into deep seas, maximizing hydrocarbon extraction at an acceptable cost is one of the greatest challenges facing the industry today. In this regard, considerable attention has been given to understanding the flow behavior in long and deep flow line risers of different topologies through transient multiphase simulation. However, the application of the large diameter to the above scenario is still an unresolved issue creating a great deal of uncertainty. This is mainly due to the limitation of the available experimental and field data being confined to much smaller diameters.

In view of the aforementioned, an experimental campaign to investigate the flow behavior in a 254-mm nominal-diameter horizontal flow line vertical riser has been performed. A numerical model to study the dynamic behavior of the large-diameter horizontal flow line vertical riser system is also developed using OLGA software with the intention of identifying the capability of this software. This article presents the comparison of the simulation and experimental data in terms of near riser base and flow line pressure variations along with flow regime predictions. The existence of the multiple roots in the OLGA code is also reported for the first time. Additionally, a review on the state-of-the-art application of the code and analysis of the numerical experiment performance of the code are included.     

基于Pearson相关系数的集输管道流动腐蚀主控因素分析

油气田集输管道腐蚀穿孔直接影响油田的安全、环境和生产,明确管道腐蚀的主控因素至关重要.采用多相流瞬态模拟软件OLGA建立管道的里程-高程模型,模拟管道内部流动状态,如温度、压力、持液率、壁面剪切力、气液相流速等参数,利用Pearson相关系数确定影响腐蚀的主控因素,结果表明:随着里程的增加,温度、压力和持液率呈现降低的...     

基于OLGA的起伏湿气集输管道水力特性研究

由于多相流动的经济性,气田大部分集输管道都采用气液混输技术。集输管线在通过地形起伏的地区时,气体的压力、温度及流速将随之变化,地形起伏不均是造成气田气液混输管道生产不稳定的一个重要因素。采用多相流模拟软件OLGA建立了湿气集输管道水力计算模型,模拟分析了地形起伏程度、管道输气量、管径、含水率对管道压降的影响。并对不同影响因素下的模拟结果进行分析,该分析结果为地形起伏地区气田集输管道的运行管理和设计提供了理论基础。     

Severe Slugging In a Catenary-shaped Riser: Experimental and Simulation Studies

Abstract:

A series of experiments on two-phase, air-water flow in a flowline-riser geometry have been made. The riser has a catenary-shaped form (10.5 m high), and the flowline has a 2-degree downward inclination toward the riser-base (10.16 cm ID). Experimental data were used to characterize the severe slugging and unstable flows in terms of pressure cycling and fluid production characteristics. A model to study dynamic behavior of severe slugging flow in a pipeline-riser system was also developed under the environment of the OLGA2000 code, and experimental test results were compared with the OLGA model predictions. The motive for this work was to identify areas that pose substantial difficultly to the code for the simulation of severe slugging in a catenary-shaped riser. In addition, numerical experiments, exploring some of the reasons for difference between experimental and simulation results, have been presented in this article.     

深水立管严重段塞流控制方法及其模拟分析

深水立管中常会出现严重段塞流,如果不加以控制,会带来严重的流动安全问题。为此,对国内外深水立管严重段塞流控制方法进行了全面调研和分析,总结了每种控制方法的优缺点、现场应用情况和适用范围。在此基础上利用某深水油气田的海管和立管资料,采用多相流瞬态模拟软件OLGA模拟了典型年份的流动状况,对段塞流最严重年份分别采用节流法、气举法、节流和气举结合法等方法进行了模拟,并探讨了管径与段塞流的关系。结论认为：该油气田生产后期会出现严重段塞流;在管径优化和设计阶段要充分考虑严重段塞流的影响;不同的段塞流控制方法适用于不同的工况,针对具体深水工程项目,应在开展软件模拟分析时综合考虑各种因素,最终选取经济、有效的段塞流控制方法。     

Severe Slugging in Flexible Risers: Review of Experimental Investigations and OLGA Predictions

Flexible risers are key components of floating production systems, particularly in harsh environmental conditions where the riser must deal with substantial vessel motion. Liquid slugging in flexible risers often causes severe operational problems for the downstream production system. To avoid such costly delays, it would be desirable to predict severe slugging behavior in flexible risers using experiments and transient codes. This article details the basic mechanisms and general characteristics of severe slugging in a pipeline-riser system. It also tries to present the research studies that have been carried out on severe slugging in flexible risers in two parts; experiments on different flexible riser configurations, and existing OLGA code predictions.     

番禺气田天然气管道积液及清管可行性分析

采用PIPEPHASE和OLGA软件模拟实验,计算海管运行中的压力分布和产液量之间的关系,并根据计算结果进行清管可行性分析与研究。