产品展厅>>项目研发>>马必东区块煤层气压力恢复试井技术服务

煤层气井的快排和慢排对煤层气井动态渗透率存在直接的影响,随着排采的进行和压力的改变,裂缝的受力状态和张开度的变化使渗透率区域降低而影响产能。快排和慢排队煤层气渗透率的影响机理有多种理论依据,但大部分并没有用实测数据进行验证并应用到实际工程中。为分析煤层气井的慢排方式,该气井渗流能力的影响程度,需要进行关井压恢测试、定压排采测试及地层压力恢复测试,研究分析压后排采方式对气井渗流能力的影响规律及利用压力恢复试井解释的压力结果评价应力状态,实现对煤层气井的综合评价。

单相水阶段测试要求:

采用井下关井方式,地面直读测试工艺,一开一关一开排液,开井排液阶段进行定流压降幅(一开慢排、二开快排)排液作业,保证气体不解吸的情况下,关井压恢测试;压力降至解吸压力附近进行定压排采30天,测试定压排采过程中水相渗透率变化情况,保证气体不解吸的情况下,再次测试地层压力恢复情况。

针对开井流压和关井压力恢复数据点的采集,为了保持与管式泵同步,均采用相同的采样时间间隔:下井、开井排液和关井压力恢复阶段,均采用每5分钟采1个数据点。

测试效果

验证压后排采方式对气井渗流能力的影响程度

对比见套压后,不同放气压力压裂裂隙含气饱和度情况

验证稳定套压放气达产过程对气井水的渗流能力变化情况

对比同一口井见套压前后地层压力恢复情况

验证分层合采解吸前排水过程层的产水能力

在测试分析基础上,结合排采实际,研究不同排采方式(憋压和不憋压)对储层气水两相流渗流能力的影响规律。同时利用压力恢复试井测试的压力结果评价应力状态。

油气井生产中会产生各类数据,如压力恢复测试及生产动态数据等,不同数据有着不同的分析评价方法,我公司长期进行石油行业技术研究及服务,具有系统化的分析软件,包括辰工压裂停泵数据解释分析软件、辰工试井分析软件、辰工生产数据分析软件、辰工油气井节点分析软件等各类软件,能够充分利用油气田生产的各类数据,实现对地层及压后效果的正确评价,从而获得可靠的储量及产能,为实现油气田高效经济开发提供关键数据及优化方案,具有同类公司没有的巨大优势。

Products>>Project Development>>Technical services for coalbed methane pressure recovery well testing

The fast and slow discharge of CBM wells have a direct effect on the CBM wells dynamic permeability, and with the process of drainage and the change of pressure, the change of stress state and opening degree of cracks reduce the permeability area and affect the production capacity. The influence mechanism of coalbed gas permeability of fast and slow discharge has many theoretical bases, but most of them are not verified by the measured data and applied to the actual engineering. In order to analyze the slow discharge method and influence degree of the seepage capacity of the CBM well, it is necessary to carry out the shut in pressure recovery test, the constant pressure discharge test and the formation pressure recovery test.

Though research analyzes, the influence of after pressure drainage method on the seepage capacity of gas wells and the pressure result by using pressure recovery well test explanation, to realize the comprehensive assessment of CBM wells.

Single phase water state testing requirements:

Adopting the downhole shut-in method, the surface direct reading test technology, open-close-open drainage, constant flow and pressure drop drainage is carry on during open well drainage stage (slow drainage for the first open well, quick drainage for the second open well), under the condition that the gas is not desorbed, the shut in pressure recovery test is carried out, and the pressure is reduced near the desorption pressure and the constant pressure drainage process will last for 30 days to test the change of water permeability in the process of constant pressure drainage, and to test the formation pressure recovery condition again when we guarantee the gas is not desorbed.

For the collection of data points for open well flowrate pressure and shut-in pressure recovery, in order to maintain synchronization with the tubular pumps, the same sampling time intervals are used: one data point is taken every 5 minutes for the down, open well drainage and shut-in pressure recovery stages.

Test results

To verify the influence of the after-pressure discharge mode on the seepage capacity of gas wells.

The gas saturation of fracturing fractures with different gas discharge pressure after casing pressure is compared.

To verify the change of the seepage capacity of gas well and water in the process of stable casing pressure.

Compare the formation pressure recovery condition before and after casing pressure in the same well.

To verify the water producing capacity of the drainage process layer prior to stratified combined production and desorption.

Based on the test and analysis, combine the drainage reality, the influence of different drainage methods on the seepage capacity of gas-water reservoir two-phase flow is studied. At the same time, the stress state is evaluated by using the pressure recovery well test results.

All kinds of data will be produced in oil and gas well production, such as pressure recovery test and production dynamic data, different data have different analysis and evaluation methods, our company has carried on the oil industry technical research and service for a long time, has the systematic analysis software, including Chengong stop pump fracture data interpretation and analysis software, Chengong well testing analysis software, Chengong production data analysis software, Chen gong oil and gas well node analysis software and so on, we can make full use of all kinds of data of oil and gas field production, realize the correct evaluation of formation and after-pressure effect, thus obtain the reliable reserves and production capacity, provide the key data and optimization scheme for the high efficiency development of oil and gas field, we have great advantage than other kind of companies.