Elemental Sulfur Deposited in Acid fractured Carbonate Sour Gas Wells
Received date: 2007-11-01
Revised date: 2008-04-02
Online published: 2008-06-10
硫沉积是高含硫气藏开发过程中的常见现象,不仅给生产设备带来严重的安全隐患,也容易造成地层堵塞,是影响该类气藏安全高效开发的重要因素之一，但目前国内外对地层中硫沉积条件的研究都是基于简单的静态环境,预测结果往往与实际存在较大差异。在综合考虑基岩和裂缝渗流空间特征以及气流水动力对析出的硫颗粒运移影响的基础上,建立了描述碳酸盐岩酸压气井生产过程中硫沉积预测模型。结果表明:流体水动力是建立硫沉积预测模型必须考虑的因素之一；硫在基岩中的沉积主要发生在距井底和靠近裂缝面相对较小的区域,且沿井底向裂缝纵深方向和垂直于裂缝向外延伸的方向上,硫沉积量和沉积速率均呈递减下降的趋势；硫在裂缝中的沉积距井底距离越近,硫沉积量越大且沉积速率相对较快；无论是基岩或裂缝中的硫沉积,随着生产时间的延长,其沉积速率呈加速变化趋势。
曾平;岑芳 . 高含硫碳酸盐岩酸压气井硫沉积规律研究[J]. 天然气地球科学, 2008 , 19(3) : 414 -418 . DOI: 10.11764/j.issn.1672-1926.2008.03.414
It’s a common phenomenon that elemental sulfur deposits in formations, which not only brings serious damages to production equipment, but also easily plugs permeability channels. This is one of key factors that affect the safe and effective development of sour gas reservoirs. Because of modeling on just static environments and neglecting the behavior of gas current hydrodynamic force to elemental sulfur particles, the results predicted by many models had great errors compared to the actual data. This paper presents a new theory model which considers the effects of gas current hydrodynamic force on elemental sulfur particles transporting. Research shows that: (1) gas velocity is a factor that must be considered while modeling; (2) elemental sulfur occurred mainly in a relatively small region close to the well bottom and the fractures; (3) the quantity and settling rate of elemental sulfur deposition decrease progressively along the well bottom to the fractures; (4) regardless of elemental sulfur deposited in the matrix or the fractures, the setting rate increases with production time.
Key words： Carbonate rock; Sour gas; Sulfur deposition; Acid fracturing; Base rock; Fracture; Plugging.
［1］Civan F.A Generalized Model for Formation Damage by Rock-Fluid Interactions and Particulate Process［R］.Paper SPE 21183,Oct 14-19,1990.
［2］Civan F.Modeling and Simulation of Formation Damage by Organic Deposition［C］//Proceedings of the First International Symposium on Colloid Chemistry in Oil Production:Asphaltenes and Wax Deposition.ISCOP'95,Rio de Janeiro,Brazil,Nov,1995:399-412.
［3］Gruesbeck C,Collins R E.Particle transport through perforations［J］.SPE J,1982,(4):857-865.
［4］Ohen H A,Civan F.Predicting Fines Generation,Migration and Deposition Near Injection and Production Wells［C］//Proceedings of the First Regional Meeting,American Filtration Society,Houston,Texas,Oct,1989:161-164.
［5］Civan F.A Multi-Purpose Formation Damage Model［R］.paper SPE 31101.
［6］Rege S D,Fogler H S.Network Modeling and Experimental Investigation of Flow,Dissolution,Precipitation and Fines Migration in Porous Media［D］.PhD Dissertation,Univ of Michigan,Ann Arbor,1998.
［7］Rege S D,Fogler H S.Competition among flow,dissolution and precipitation in porous Media［J］.AICHEJ,1989,35:1177-1185.
［8］Kuo C H.On the production of hydrogen sulfide-sulfur mixtures from deep formations［J］.JPT,1972，(3):1141.
［9］Bruce E.The Effect of Sulfur Deposition on Gas Well Inflow Performance［R］.Paper SPE 36707.
［10］Hyne J B,Derdall G.Sulfur Deposition in Reservoirs and Production Equipment: Sources and Solutions［C］//Paper presented at the Annual Gas Condtioning Conference.Norman,Oklahoma:University of Oklahoma,March 3-5,1980.
［11］Hyne J B. Controlling sulfur deposition in sour gas wells[J].World Oil,1983,35.
［12］Bruce E.The Effect of Sulfur Deposition on Gas Well Inflow Performance［R］.Paper SPE 36707.
［13］Abou-Kassem J H.Experimental and numerical modeling of sulfur plugging in carbonate reservoirs[J].SPE J,2000,26:91-103.
［14］Al-Awadhy F,Kocabas I,Abou-Kassem J H.Experimental and Numerical Modeling of Sulfur Plugging in Carbonate Oil Reservoirs［R］.Paper SPE 49498.
［15］Frauk Civan.Modeling Well Performance Under Nonequilibrium Deposition Conditions［R］.Paper SPE 67234,2001.
［16］Shedid A.Shedid.Formation Damage Due to Simultaneous Sulfur and Asphahene Deposition［R］.Paper SPE 86533.presented at the SPE International Symposium and Exhibition on Formation Damage Control held in Lafayette,Louisiana,USA,2004.
［17］曾平,赵金洲,周洪彬.高含硫气藏元素硫沉积对储集层的伤害［J］.石油勘探与开发,2005,26(6):113-115.
［18］杨学锋,胡勇.高速非达西流动时元素硫沉积模型研究［J］.天然气地球科学,2007,18(5):764-766.
［19］曾平.高含硫碳酸盐岩气藏低伤害酸压技术及压后硫沉积规律研究［D］.西南石油大学,博士学位论文,2006.
/
| 〈 |
|
〉 |
甘公网安备 62010202000678号