The Determination of Casing Releasing Pressure of CBM Wells and Its Application
-
摘要: 煤层气井提产阶段和稳产阶段需要确定合理放气套压,才能够获得稳定的气流补给。根据煤储层启动压力梯度、渗流理论和煤层气开发地质理论,构建了煤层气井憋压阶段套压变化的数学模型;利用沁水盆地大宁区块的煤层气勘探开发资料验证了该模型的准确性,并分析了放气套压差值对平均日产气量的影响规律。模型计算结果与现场数据吻合较好时,煤层气井的产气量较高;当计算出的放气套压与实际放气套压的差值小于等于0.15 MPa时,煤层气井稳产期的产气量能达到1 000 m3/d以上;大于0.15 MPa时,需要降低产气量来维持其稳定性。研究结果表明,日产气量随实际放气套压与计算值之间差值的增大呈幂函数减小,建立的煤层气井憋压阶段合理放气套压数学模型可为现场排采控制提供理论依据。Abstract: In the stage of stable production and production increase of coalbed methane wells, it is necessary to determine the reasonable casing releasing pressure to obtain stable air supply. Based on the threshold pressure of coal reservoir, seepage theory, CBM development geology theory etc., a mathematic model of releasing pressure for CBM wells was established. From CBM exploration and development data of Daning Block, Qinshui Basin, the accuracy of the mathematic model was verified. The relations between casing pressure drop and average daily gas production were analyzed. When predicted pressure from this model was in good agreement with that applied in field data, gas production of CBM Wells would be higher. When the pressure difference was within 0.15 MPa, the average daily gas production of CBM wells could be more than 1 000 m3/d in stable production stage. When the pressure difference was more than 0.15 MPa, daily gas production would be stabilized at lower gas production rate. The results showed that daily gas production is reduced in power function with casing pressure drop and the mathematical model of casing releasing pressure in coal bed methane well can provide theoretical basis for CBM wells production.
-
Keywords:
- coalbed methane /
- pressure build up stage /
- drainage /
- production system /
- casing releasing pressure
-
-
[1] Harpalani S,Shraufnagel R A.Shrinkage of coal matrix with release of gas and its impact on permeability of coal[J].Fuel,1990,69(4):551-556.
[2] Clarkson C R,Bustin R M.The effect of pore structure and gas pressure upon the transport properties of coal a laboratory and modeling study[J].Fuel,1999,78(1):1345-1362.
[3] Bustin R M.Importance of fabric and composition on the stress sensitivity of permeability in some coal Northern Sydney Basin,Australia relevance to coalbed methane exploitation[J].AAPG Bulletin,1997,81(11):171-184.
[4] 张政,秦勇,Wang Guoxiong,等.基于等温吸附实验的煤层气解吸阶段数值描述[J].中国科学:地球科学,2013,43(8):1352-1358. Zhang Zheng,Qin Yong,Wang Guoxiong,et al.Numerical description of coalbed methane desorption stages based on isothermal adsorption experiment[J].Science China: Earth Sciences,2013,43(8):1352-1358. [5] 毛慧,韩国庆,吴晓东,等.煤层气井气水两相流动阶段流入动态研究[J].断块油气田,2011,18(4):502-504. Mao Hui,Han Guoqing,Wu Xiaodong,et al.Study on inflow performance in gas-water two-phase flow stage of coalbed methane well [J].Fault-Block Oil Gas Field,2011,18(4):502-504. [6] 康永尚,赵群,王红岩,等.煤层气井开发效率及排采制度的研究[J].天然气工业,2007,27(7):79-82. Kang Yongshang,Zhao Qun,Wang Hongyan,et al.Developing efficiency and the working system of wells during the de-watering gas production process in coalbed ethane reservolrs[J].Natural Gas Industry,2007,27(7):79-82. [7] 杨秀春,李明宅.煤层气排采动态参数及其相互关系[J].煤田地质与勘探,2008,36(2):19. Yang Xiuchun,Li Mingzhai.Dynamic parameters of CBM well drainage and relationship among them[J].Coal Geology Exploration,2008,36(2):19. [8] 李国富,侯泉林.沁水盆地南部煤层气井排采动态过程与差异性[J].煤炭学报,2012,37(5):798-803. Li Guofu,Hou Quanlin.Dynamic process and difference of coalbed methane wells production in southern Qinshui Basin[J].Journal of China Coal Society,2012,37(5):798-803. [9] 石惠宁,马成宇,梅永贵,等.樊庄高煤阶煤层气井智能排采技术研究及应用[J].石油钻采工艺,2010,32(4):107-111. Shi Huining,Ma Chengyu,Mei Yonggui,et al.Research and application of intelligent recovery technology for Fanzhuang high rank CBM wells[J].Oil Drilling Production Technology,2010,32(4):107-111. [10] 李清,赵兴龙,谢先平,等.延川南区块煤层气井高产水成因分析及排采对策[J].石油钻探技术,2013,41(6):95-99. Li Qing,Zhao Xinglong,Xie Xianping,et al.Causes of high water yield CBM wells in Yanchuannan Block and draining measures[J].Petroleum Drilling Techniques,2013,41(6):95-99. [11] 曲占庆,翟恒立,田相雷,等.考虑压敏效应的变启动压力梯度试验研究[J].石油钻探技术,2012,40(3):78-82. Qu Zhanqing,Zhai Hengli,Tian Xianglei,et al.Experimental research on variable threshold pressure gradient considering pressure sensitive effect[J].Petroleum Drilling Techniques,2012,40(3):78-82. [12] 郭红玉,苏现波.煤储层启动压力梯度的实验测定及意义[J].天然气工业,2010,30(6):52-54. Guo Hongyu,Su Xianbo.An experimental measurement of the threshold pressure gradient of coal reservoirs and its significance[J].Natural Gas Industry,2010,30(6):52-54. [13] 葛家理.现代油藏渗流力学原理[M].北京:石油工业出版社,2003:81-89. Ge Jiali.Themodren mechanics of fluids flow in oil reservoir[M].Beijing:Petroleum Industry Press,2003:81-89. -
期刊类型引用(6)
1. 邱春阳,王重重,姜春丽,王俊,秦涛,杨倩云. 陕西榆林废弃钻井液固液分离技术研究. 精细石油化工. 2024(02): 48-51 . 百度学术
2. 张颖,温钰奇,李辉,庞凯,罗会清. 高含水钻井固废超细颗粒过滤分离实验研究. 应用化工. 2024(02): 293-296 . 百度学术
3. 舒小波,陈俊斌,欧翔. 水基钻井液劣质固相控制及其现场应用. 石油地质与工程. 2023(05): 90-93+99 . 百度学术
4. 王景. 临兴–神府井区废弃钻井液处理技术. 石油钻探技术. 2022(01): 60-64 . 本站查看
5. 许毓,刘晓辉,马滢,谢水祥,任雯,张明栋,仝坤. 废水基钻井液中固相颗粒电吸附选择性实验. 石油钻采工艺. 2022(01): 31-36 . 百度学术
6. 谭敬鹏,李之军,沈建鑫. 基于电吸附理论的金刚石钻探超细固相清除技术实验研究. 四川地质学报. 2022(S1): 3-6+12 . 百度学术
其他类型引用(1)
计量
- 文章访问数: 3032
- HTML全文浏览量: 76
- PDF下载量: 4409
- 被引次数: 7