水平井是解决低渗透薄油层多井低产、实现高效开发的重要手段，但这些水平井几乎都需要压裂改造。经过近几年的攻关，水平井压裂工艺技术由最初的全井笼统限流法压裂发展为双封单卡分段压裂、机械桥塞分段压裂、段内限流多段压裂、水力喷砂压裂、胶塞压裂等。这些工艺技术对提高水平井开发效果起到了明显的促进作用，但仍满足不了低-特低渗透储层高排量、大规模压裂的要求。为此，试验了连续油管水力喷射环空加砂压裂工艺，取得了较好的压裂增产效果。

Horizontal well in low permeability and thin oil layer is to solve the multi wells, an important means to realize the efficient development of horizontal well, but these are almost all need fracturing.Through the research of recent years, horizontal well fracturing technology by full well the original general limited entry fracturing technology for the development of double seal single card staged fracturing, mechanical bridge plug fracturing, period segment limiting the multi stage fracturing,Hydrajet fracturing, the rubber plug fracturing etc. The technology to the obvious effect on promoting the increase of horizontal well development effect, but still can not meet the needs of lowand ultra-low permeability reservoir high displacement, large scale fracturing requirements.Therefore, testing of coiled tubing jet annular sand fracturing technique, has obtained the goodeffect of fracturing stimulation.

为了准确预测非对称裂缝压裂气井的产能,指导和优化气井压裂,根据保角变换原理,通过引入气体压力函数,建立了裂缝内气体流动的微分方程组,最后通过求解微分方程组得到了非对称裂缝压裂气井的产量计算公式。利用某油田非对称裂缝压裂气井的数据,验证了推导出的非对称裂缝压裂气井产量计算公式的准确性。利用该计算公式分析了裂缝的非对称性对压裂气井产能的影响,结果表明：在其他参数相同的条件下,裂缝的非对称性越严重,压裂气井的产量越低;当井底流压较高时,裂缝的非对称性对压裂气井产量的影响较小;当井底流压较低时,裂缝的非对称性对压裂气井产量的影响较大。因此为获得较高的产能,应尽可能保证压裂裂缝沿井筒对称分布。

In order to accurately predict the productivity of asymmetrically fractured gas wells and op-timize gas wells fracturing ,according to the conformal transformation principle ,the productivity computa-tion formula for such wells was established by introducing the gas pressure function and solving the differ-ential equations for gas flow in fractures .This formula was validated by the real data of asymmetrically fractured gas wells in an oil field .The effects of fracture asymmetry on the productivity of fractured gas wells was analyzed with this formula .The results showed that ,given the same parameters ,the more the a-symmetry of fractures ,the lower the production of fractured gas wells .When the flowing bottomhole pres-sure is higher ,the production of asymmetrically fractured gas wells is less affected by the asymmetry of fractures ,but for the lower flowing bottomhole pressure ,the effect is just contrary .So ,the fractures should be kept in symmetric distribution along the wellbo

煤层气压裂作业中必然发生压裂液与煤层的相互接触,煤岩微裂隙发育和毛管压力高等特点导致压裂液极易侵入煤层对煤岩孔隙结构造成严重损害,进而改变煤岩对煤层气的吸附能力。选取宁武盆地9号煤和现场用压裂液,采用氮气吸附和扫描电镜(SEM)表征压裂液处理前后煤样孔隙结构,探求不同体系压裂液处理对煤岩孔隙结构的影响,开展压裂液处理前后煤样的等温吸附实验。结果表明:压裂液处理后煤样孔径分布、比表面积及孔隙分形维数都将发生变化;压裂液体系对煤样孔隙结构的影响程度为瓜胶压裂液活性水压裂液清洁压裂液;压裂液处理后煤样比表面积与孔隙分形维数增量越大,其对甲烷气体吸附能力越强,煤岩孔隙结构的变化会改变甲烷气体的吸附能力。

Fracturing fluid and the coal seam will touch each other during fracturing operation of coal. The developed micro-fractures and high capillary pressure of coal make it easy for fracturing fluid intrude into coal seam and therefore cause serious damage to the pore structure, which affects further the adsorption capacity of coal bed methane. Using the NO. 9 coal sample from Ningwu Basin and three fracturing fluid samples on site, the characterization of pore structure of coal, which was treated with fracturing fluid, was analyzed with nitrogen adsorption method. Combined with the analysis results of scanning electron mi-croscopy ( SEM) , the influence of different fracturing fluid on pore structure of coal was investigated. Methane isothermal ad-sorption experiments were also carried out using the treated coal. The results show that pore size distribution, specific surface area and pore fractal dimension of coal change after treated by fracturing fluid. The results also indicat

压裂是改造储层促进增产的重要施工手段,随着体积压裂等大规模施工工艺技术的应用,压裂液用量越来越大,压裂施工后返排液量也随之大幅增加,这些压裂返排液的大量排放造成了污水处理成本的骤增,污染物排放的加大。通过压裂返排液回收再利用技术的介绍,以促进节水减排工艺技术的进步,为绿色石油、环保中国多作贡献。

Fracturing is an important construction method to promote reservoir production; along with large-scale application of the construction technology, fracturing fluid consumption is larger and larger, the amount of fracturing flowback fluid after the construction has been greatly increased, the emission of fracturing flowback fluid caused an explosion of sewage treatment cost, increase of pollutants. In this paper, the recycling technology of fracturing flowback fluid was discussed to promote the progress of technique of water saving and emissions reduction.

采用真三轴岩土工程模型试验机、压裂泵伺服控制系统、Disp声发射三维空间定位技术、试验前后工业CT扫描水力压裂缝扩展形态的方法,建立一套页岩水力压裂物理模拟与压裂缝表征方法。由页岩水力压裂物理模拟试验可得:(1)采用Disp声发射八探头三维空间定位监测方法,能实时有效地监测水力压裂缝的起裂位置;(2)采用水力压裂后追踪红色示踪剂痕迹的方式,可实现水力压裂缝的空间形态描述;(3)当水力压裂未形成沿天然层理面的贯通压裂缝时,易形成与天然层理面相交的压裂缝,并与层理面开裂后交叉形成网络裂缝。建立的页岩水力压裂物理模拟试验与表征方法,可进行页岩压裂施工参数的优化设计,为页岩气储层水力压裂开采提供技术支持。

In order to study the hydraulic fracture and crack shape,the large real triaxial simulation experimental system,servo control system of hydraulic fracturing equipment,Disp acoustic emission(AE) three-dimensional orientation technique and CT scanning technique are applied;and the hydraulic fracturing physical simulation testing method and the characterization methods of hydraulic fracture have been established. According to the test,some conclusions are drawn as follows. (1) Using 8 transducers acoustic emission(AE) sources orientation technique,starting-crack pressure and the direction of hydraulic fracture can be monitored continuously. (2) Adding a red tracer into fracturing fluid and parting the sample can describe the spatial morphology of the hydraulic fracturing. (3) When the hydraulically created fracture extended is not along the natural bedding plane, it can easy to form the network crack. The physical simulation and characterization methods of hydraulic fracturing can be used