﻿ 海上非凝结气与过热蒸汽混注井筒传热特征研究

1. 中国石油大学(北京)石油工程学院, 北京 102249;
2. 油气资源与探测国家重点实验室(中国石油大学(北京)), 北京 102249

Characteristics of Heat Transfer in Offshore Wellbores with Non-Condensing Gases Flow Coupled with Overheated Steam
SUN Fengrui1,2, YAO Yuedong1,2, LI Xiangfang1, SUN Zheng1, CHEN Gang1
1. College of Petroleum Engineering, China University of Petroleum(Beijing), Beijing, 102249, China;
2. State Key Laboratory of Petroleum Resources and Engineering(China University of Petroleum(Beijing)), Beijing, 102249, China
Abstract: To optimize injection parameters of non-condensing gas and overheated steam (steam/gas mixture) in offshore heavy oil reservoirs, a mathematical model of non-isothermal flow in wellbore was established following the conservation equations of mass, energy and momentum.Taking into account the heat-transfer model for seawater and transient thermal conductivity model in reservoir formation, an integral heat transfer model in wellbore with steam/gas mixture was established.By using finite difference method and iterative method, pressure and temperature distributions within the wellbore were obtained.Research results show seawater flow results in significant heat losses in the wellbore and reduces temperatures of steam/gas mixture.When the amount of non-condensing gases increases, the temperature and overheat degrees of the mixed steam/gas may decrease.Likewise, with the increase of steam injection pressure, the overheat degrees may decrease.The heat transfer model for wellbores with mixed steam/gas may provide a theoretical basis for optimizing the parameters of steam injection and creating an effective analysis of seawater on heat losses in wellbores.
Key words: heavy oil reservoir     turbulent seawater flow     non-condensing gas     overheated steam     thermophysical properties     parameters for steam-injection operation

1 数学模型的建立 1.1 基本假设

 图 1 海上注汽井井筒结构示意 Fig.1 Schematic structure of offshore wellbore for steam injection
1.2 非等温流动数学模型

 (1)

 (2)

 (3)

1.3 模型中参数计算方法

 (4)

S-R-K方程在石油工程中应用广泛，具体算法如下[5, 13, 24]

 (5)

 (6)
 (7)
 (8)

 (10)

 (11)

 (12)
 (13)

1.4 模型求解

2 热损失影响因素分析

 图 2 模型计算压力和温度与实测值对比 Fig.2 Measured and calculated pressure and temperature

2.1 非凝结气含量

 图 3 非凝结气含量对井筒内热物性参数分布的影响曲线 Fig.3 Impact of mass fraction of non-condensing gas on the distribution of thermo-physical properties in a wellbore

2.2 注汽速度

 图 4 注汽速度对井筒内热物性参数分布的影响曲线 Fig.4 Impact of steam-injection rates on the distribution of thermo-physical properties in a wellbore

2.3 注汽压力

 图 5 注汽压力对井筒内热物性参数分布的影响曲线 Fig.5 Impact of steam-injection pressure on the distribution of thermo-physical properties in a wellbore

3 结论

1) 计算结果表明，海水的流动能明显增加井筒热损失速率，海水段井筒内的温度梯度明显高于地层段内的温度梯度，但海水的流动对井筒内压力的分布影响很小。

2) 随着非凝结气含量增加，混合汽/气的温度和过热度均下降；随着注汽压力增加，过热度不断下降。现场应结合设备条件降低注汽压力、提高注汽温度，以获得更好的开发效果。

3) 现场生产过程中油管与套管可能发生接触而导致油管内热能快速流向套管，下一步研究时应考虑油管与套管的接触传热对井筒内热物性参数分布的影响。

 [1] 杨戬, 李相方, 陈掌星, 等. 考虑稠油非牛顿性质的蒸汽吞吐产能预测模型[J]. 石油学报, 2017, 38(1): 84–90. YANG Jian, LI Xiangfang, CHEN Zhangxing, et al. A productivity prediction model for cyclic steam stimulation in consideration of non-Newtonian characteristics of heavy oil[J]. Acta Petrolei Sinica, 2017, 38(1): 84–90. DOI:10.7623/syxb201701009 [2] 周娜, 姜东, 杜玮暄, 等. 稠油井过泵旋流混合降黏举升技术[J]. 石油钻探技术, 2016, 44(6): 84–87. ZHOU Na, JIANG Dong, DU Weixuan, et al. Lifting technology by swirl pumping vortex-reducing viscosity for heavy oil production well[J]. Petroleum Drilling Techniques, 2016, 44(6): 84–87. [3] 孙逢瑞, 姚约东, 李相方, 等. 过热蒸汽吞吐水平井加热半径及产能预测模型[J]. 特种油气藏, 2017, 24(2): 120–124. SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. Forecast model for heating radius and productivity of horizontal wells with overheated steam soaking[J]. Special Oil & Gas Reservoirs, 2017, 24(2): 120–124. [4] 孙逢瑞, 姚约东, 李相方, 等. 热采水平井注多元热流体水平段传质传热模型[J]. 断块油气田, 2017, 24(2): 259–263. SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. Mathematical modeling of mass and heat transfer process for multi-component thermal fluid injection wells[J]. Fault-Block Oil & Gas Field, 2017, 24(2): 259–263. [5] 陶磊, 李松岩, 程时清. 稠油油藏水平井泡沫酸解堵技术[J]. 石油钻探技术, 2015, 43(6): 76–80. TAO Lei, LI Songyan, CHENG Shiqing. Foamed acid plug-removal technique for horizontal wells in heavy oil reservoirs[J]. Petroleum Drilling Techniques, 2015, 43(6): 76–80. [6] 孙逢瑞, 黄世军, 邹明. 过热蒸汽吞吐水平井产能评价模型[J]. 特种油气藏, 2016, 23(3): 122–125. SUN Fengrui, HUANG Shijun, ZOU Ming. Productivity forecast model of horizontal well with superheated steam huff-puff[J]. Special Oil & Gas Reservoirs, 2016, 23(3): 122–125. [7] 孙逢瑞, 姚约东, 李相方, 等. 稠油油藏蒸汽吞吐水平井生产动态分析[J]. 断块油气田, 2017, 24(1): 83–86. SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. Production performance of cyclic steam stimulation horizontal well in heavy oil reservoirs[J]. Fault-Block Oil & Gas Field, 2017, 24(1): 83–86. [8] 孙逢瑞, 姚约东, 李相方, 等. 基于R-K-S方程的同心双管注多元热流体传热特征研究[J]. 石油钻探技术, 2017, 45(2): 107–114. SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. An R-K-S equation-based study on the heat transmission features of multi-component thermal fluid injection through concentric dual-tubing[J]. Petroleum Drilling Techniques, 2017, 45(2): 107–114. [9] SUN Fengrui, LI Chunlan, CHENG Linsong, et al. Production performance analysis of heavy oil recovery by cyclic superheated steam stimulation[J]. Energy, 2017, 121: 356–371. DOI:10.1016/j.energy.2016.12.132 [10] de ALMEIDA R V, RAHNEMA H, McMILLAN M D. Wellbore modeling for hybrid steam-solvent processes[J]. Fuel, 2017, 188: 50–60. DOI:10.1016/j.fuel.2016.10.013 [11] 孙逢瑞, 姚约东, 李相方. 海上主副油管注过热蒸汽热损失等效算法探讨[J]. 北京石油化工学院学报, 2017, 25(2): 15–18, 24. SUN Fengrui, YAO Yuedong, LI Xiangfang. An equivalent evaluation model for heat loss of superheated steam flow in offshore parallel dual-tubing wells[J]. Journal of Beijing Institute of Petrochemical Technology, 2017, 25(2): 15–18, 24. [12] SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. The mass and heat transfer characteristics of superheated steam coupled with non-condensing gases in perforated horizontal wellbores[J]. Journal of Petroleum Science and Engineering, 2017, 156: 460–467. DOI:10.1016/j.petrol.2017.06.028 [13] SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. A numerical approach for obtaining type curves of superheated multi-component thermal fluid flow in concentric dual-tubing wells[J]. International Journal of Heat and Mass Transfer, 2017, 111: 41–53. DOI:10.1016/j.ijheatmasstransfer.2017.03.103 [14] 孙逢瑞, 姚约东, 李相方, 等. 南堡油田注多元热流体吞吐水平井加热效果评价[J]. 北京石油化工学院学报, 2017, 25(1): 5–8. SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. Evaluation of heating effect on the horizontal well in 35-2 Bohai Oilfield with multiple thermal fluid stimulation[J]. Journal of Beijing Institute of Petrochemical Technology, 2017, 25(1): 5–8. [15] SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. The flow and heat transfer characteristics of superheated steam in offshore wells and analysis of superheated steam performance[J]. Computers & Chemical Engineering, 2017, 100: 80–93. [16] SUN Fengrui, YAO Yuedong, CHEN Mingqiang, et al. Performance analysis of superheated steam injection for heavy oil recovery and modeling of wellbore heat efficiency[J]. Energy, 2017, 125: 795–804. DOI:10.1016/j.energy.2017.02.114 [17] SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. Type curve analysis of superheated steam flow in offshore horizontal wells[J]. International Journal of Heat and Mass Transfer, 2017, 113: 850–860. DOI:10.1016/j.ijheatmasstransfer.2017.05.105 [18] SUN Fengrui, YAO Yuedong, LI Xiangfang, et al. The flow and heat transfer characteristics of superheated steam in concentric dual-tubing wells[J]. International Journal of Heat and Mass Transfer, 2017, 115(part B): 1099–1108. [19] 周体尧. 稠油油藏注过热蒸汽开采机理[D]. 北京: 中国石油大学(北京), 2010. ZHOU Tiyao.Mechanism of superheated steam injection in heavy oil reservoir[D].Beijing:China University of Petroleum(Beijing), 2010. [20] XU Anzhu, MU Longxin, FAN Zifei, et al.New findings on heatloss of superheated steam transmitted along the wellbore and heating enhancement in heavy oil reservoirs[R].IPTC 16439, 2013. http://www.onepetro.org/mslib/app/Preview.do?paperNumber=IPTC-16439-MS&societyCode=IPTC [21] GU Hao, CHENG Linsong, HUANG Shijun, et al. Thermophysical properties estimation and performance analysis of superheated-steam injection in horizontal wells considering phase change[J]. Energy Conversion and Management, 2015, 99: 119–131. DOI:10.1016/j.enconman.2015.04.029 [22] 范子菲, 何聪鸽, 许安著. 水平井注过热蒸汽井筒沿程参数计算模型[J]. 石油勘探与开发, 2016, 43(5): 798–805. FAN Zifei, He Congge, XU Anzhu. Calculation model for on-way parameters of horizontal wellbore in the superheated steam injection[J]. Petroleum Exploration and Development, 2016, 43(5): 798–805. [23] 李兆敏, 张丁涌, 衣怀峰, 等. 多元热流体在井筒中的流动与传热规律[J]. 中国石油大学学报(自然科学版), 2012, 36(6): 79–83, 88. LI Zhaomin, ZHANG Dingyong, YI Huaifeng, et al. Flow and heat transfer regulation of multi-thermal fluids injection in wellbore[J]. Journal of China University of Petroleum (Edition of Natural Science), 2012, 36(6): 79–83, 88. [24] 程文龙, 韩冰冰. 基于实际气体状态方程的多元热流体井筒传热模型[J]. 石油学报, 2015, 36(11): 1402–1410. CHENG Wenlong, HAN Bingbing. Wellbore heat transfer model based on real gas state equation[J]. Acta Petrolei Sinica, 2015, 36(11): 1402–1410. DOI:10.7623/syxb201511009 [25] DONG Xiaohu, LIU Huiqing, ZHANG Zhaoxiang, et al. The flow and heat transfer characteristics of multi-thermal fluid in horizontal wellbore coupled with flow in heavy oil reservoirs[J]. Journal of Petroleum Science and Engineering, 2014, 122: 56–68. DOI:10.1016/j.petrol.2014.05.015 [26] 东晓虎, 刘慧卿, 侯吉瑞, 等. 非凝析气与蒸汽混注水平井井筒流动传热特征[J]. 中国石油大学学报(自然科学版), 2016, 40(2): 105–114. DONG Xiaohu, LIU Huiqing, HOU Jirui, et al. Transient fluid flow and heat transfer characteristics during co-injection of steam and non-condensing gases in horizontal wells[J]. Journal of China University of Petroleum (Edition of Natural Science), 2016, 40(2): 105–114. [27] 刘慧卿. 热力采油原理与设计[M]. 北京: 石油工业出版社, 2013: 148-150. LIU Huiqing. Principle and design of thermal oil recovery[M]. Beijing: Petroleum Industry Press, 2013: 148-150. [28] 黄世军, 李秋, 程林松, 等. 海上多元热流体注入沿程热物性评价模型[J]. 西南石油大学学报(自然科学版), 2015, 37(1): 91–97. HUANG Shijun, Li Qiu, CHENG Linsong, et al. An evaluation model on a long-pipe thermal parameters of multi-component heat fluid injected in offshore reservoirs[J]. Journal of Southwest Petroleum University (Science & Technology Edition), 2015, 37(1): 91–97. DOI:10.11885/j.issn.1674-5086.2012.09.03.01 [29] 袁恩熙. 工程流体力学[M]. 北京: 石油工业出版社, 1982: 87-163. YUAN Enxi. Engineering fluid mechanics[M]. Beijing: Petroleum Industry Press, 1982: 87-163.

#### 文章信息

SUN Fengrui, YAO Yuedong, LI Xiangfang, SUN Zheng, CHEN Gang

Characteristics of Heat Transfer in Offshore Wellbores with Non-Condensing Gases Flow Coupled with Overheated Steam

Petroleum Drilling Techniques, 2017, 45(5): 92-97.
http://dx.doi.org/10.11911/syztjs.201705016