A STUDY ON TRANSIENT FLUID FLOW OF HORIZONTAL WELLS IN DUAL-PERMEABILITY MEDIA

To adopt horizontal wells in dual media reservoirs,a good understanding of the related fluid flows is necessary.Most of the recent studies focus on dual porosity media instead of dual permeability media.In this article,through both integral transformation and sink-source superposition,a new Laplace-domain solution is obtained for the slightly-compressible fluid flow in the 3-D dual-permeability media in which the horizontal well is operating in a constant rate of production.Major asymptotic characteristics of diagnosis curves of dimensionless downhole pressure are analyzed by the limited analysis.Effects of parameters of dual-permeability media including mobility ratio κ,storativity ratio ω and inter-porosity flow parameter κ on the downhole pressure are studied by using the Laplace numerical inversion.The new solution obtained in this article includes and improves the previous results and then can be used as a basis for either pressure transient analysis or formation behavior evaluation for the typical reservoir with horizontal wells.     

连通井组采卤工艺在平顶山盐田的应用

介绍了连通井组的两种主要类型:水力压裂连通井组与定向钻井连通井组。并列举了其各自的优缺点,以及常见生产事故的判断、预防与处理。     

大位移井侧位抛物线剖面设计的数值计算

侧位抛物线剖面是大位移井轨道设计中常用的剖面类型。对侧位抛物线剖面设计求解过程中的求侧位抛物线初始点井斜角的数值方法和从段长求井斜角的数值方法进行了分析,指出其关键是求解侧位抛物线初始点井斜角所满足的一个三角函数方程。用倍角公式可将该三角函数方程转化成一个四次代数方程,然后用求根公式直接求出解析解。用解析解可简化侧位抛物线剖面设计过程,减少计算工作量,提高计算速度。侧位抛物线井段参数计算中需要通过段长公式来反求井斜角,给出了反求井斜角的二分法。本文的算法可应用于大位移井轨道设计的软件开发。     

Modulated Quasi-plane Tunnel-ing Current

A new tutmeling junction can be formed by an insulator layer inserting into a quantum well, and in the quantum well, a quasi-plane tunneling current can be formed by applying a tunneling voltage. If a P-N junction is grown on the quantum well, the tunneling current can be modulated by a P-N junction-bias voltage. The modulated quasi-plane tunneling current is not only related to the bias voltage, but also to the depth of the quantum well. It is analyzed that the P-N junction-bias voltage how to affect the tunneling current and a method of measuring the depth of the quantum well is presented.     

Corrosion inhibition of Tubing steel during acidization of oil and gas wells

Acidization is an oil reservoir stimulation technique for increasing well productivity. Hydrochloric acid, HCl, is used in oil and gas production to stimulate the formation. The acid treatment occurs through steel tubes. The process requires a high degree of corrosion inhibition. The present study deals with the evaluation of the effectiveness of the new synthesized compound namely; 6-methyl-5-[m-nitro styryl]-3-mercapto-1,2,4-triazine as corrosion inhibitor for mild steel in 12% HCl solution at 50 °C using various chemical and electrochemical techniques. The results showed that anodic dissolution of mild steel was remarkably decreased. The strong adsorption ability of this new synthesized compound can be attributed to the presence of multiple adsorption centers of nitrogen as well as π-donor moieties.     

Economy of exploiting heat from low-temperature geothermal sources using a heat pump

The article describes the economy of exploiting heat from low-temperature geothermal sources for high-temperature heating of buildings using a heat pump. For the exploitation of low-temperature geothermal sources, a two stage heat pump with a heat exchanger was planned. The pump consists of two single stage heat pumps which use different refrigerants at each stage. At stage 1, the calculation of the heat pump is conducted with refrigerant R407c; at stage 2 of the heat pump, the refrigerant R600a is used. The main operational characteristics of a two stage heat pump are presented in the form of diagrams. For the exploitation of heat from geothermal water with a temperature of 45 °C, a profitability evaluation of the investment in the heat pump was carried out, using the method of the net present value. In the research, also the coefficient of profitability and the period of time in which the investment is going to return itself were established.     

北京地铁富水隧道施工综合降水技术探讨

北京地铁四号线十八标段区间隧道顶板埋深12 m,处于地下水位之下,施工中若采用地表井点降水将严重影响道路交通,井点降水施工产生的泥浆污染周边环境;同时,受限于地层渗透性小的因素,单一井点降水施工难以实现预期的降水效果,严重影响区间隧道施工安全。结合既有基坑降水技术,采用隧道内辐射井降水、管井降水和井点降水相结合的综合降水技术,解决了施工中占路难和降水施工扰民难题,为地铁施工带来了良好的社会效益。     

基于ADAM 5510M和GPRS的油井远程数据采集系统的设计与实现

将PC架构的可编程控制器ADAM5510M做为数据采集系统下位机,实现对油井工况数据的采集、存储、处理和通讯等。通过GPRS网络和Internet网络,实现下位机与远程监测中心上位机的指令响应与数据交换。本文对其数据采集系统的硬件架构、数据采集通信过程及软件功能进行了论述。     

浅薄层稠油油藏资源二次利用的一种方法—加密井蒸汽吞吐

由于河南油田稠油油藏具有“浅、薄、稠、散”的特点，所以蒸汽吞吐平均6个周期后，开发指标和经济指标明显降低。蒸汽吞吐后剩余油分布为：100m×141m及五点法并网，剩余油分布较为集中，100m×100m反七点法并网，剩余油分布零散；经济分析结果表明：浅薄层稠油油藏加密井吞吐单井的经济极限产量为1200～1500t，当油层厚度大于5.0m、纯总厚度比大于0.5，以及单井控制死油区面积大于0．5×10－2km2，且死油区离边水距离大于150m时，可进行加密，加密井蒸汽吞吐采收率可达14％左右。不同并网的加密方式为：100m×141m及五点法井网，采用直并加密方式；100m×100m反七点法并网，采用水平并加密方式。     

已开发稠油油藏水平井热采经济评价

方法利用数值模拟法，对齐平1井进行动态历史拟合与生产预测，并从钻井成本、地面建设费用、税收及油价等方面．对已开发稠油油藏─—齐40断块的齐平1井及其假设直井进行经济评价。目的利用水平井技术改善已开发稠油油藏的开发效果。结果水平井的投资为直井的3．35倍，产油量为直井的3．29倍，按油价1020．0元/t计算，净现值是直井的5．04倍。结论在目前钻井成本和油价条件下，利用水平井开发已开发稠油油藏，必须争取部分优惠政策。就辽河油区而言，每生产1t油减免47．2元，则可盈利；而直井即使每吨油税金全部减免，仍然亏15．9元。