Well-Earth ERT Non-polarized Electrodes Design And Performance Research

Now，several major oil fields have entered the high water content of oil productionperiod in China. After the existing oil drilling technology construction worked，there arestill a lot of underground crude oil failed to completely get the reasonable development inthe thousands of meters underground rock formations and becoming the remaining oil. Incurrent society, the energy is shortage, the supply and demand contradiction. Thereforestrengthen research on the distribution rule of remaining oil，advance the remaining oilexploration ability is a very important topic in today’s oil field. The Method of Well-EarthERT is proposed for reservoir development design， Electric field sensors ofnon-polarizable electrode is the most leading edge devices of the above method，it isdirectly contact with the receiver of the earth that is sensitive sensing probe. The electrodesensing signal usually will be affected by power frequency and natural potential in wellsite, changes in the ambient temperature and the influence of electrode polarizationphenomenon make changes in the signal characteristic under test, so as to causemeasurement error and interfere with the collection results.This thesis target is to prepare high-quality non-polarized electrodes, which have theadvantages of low potential range，stable performance，low noise，bandwidth，lightweightand easy to be store, starting from the aspects of preparation technology，performance，stability testing and so on, proposing a scheme，analyzing the feasibility and making theexperimental verification. Using several materials as the electrode electrolyte component,and Pb，Cu and other metals were used as internal contact bar. Different types of contactrod shape, different types of electrode casing size，different types of electrode internalmedium produce different types of non-polarized electrodes respectively which usematerial A, material B, material C as internal filling media. These preparation ofelectrodes were monitored in the same temperature, pH and the concentration of mediumfor a long time, observing experimental data，recording the relevant results which include the electrode resolution，the size of the internal resistance，noise range，potential range，the degree of precision，the indicator parameters of the settling time so as to receive theelectrode suitable shell structure, ideal medium components and a reasonable proportionof the ratio, the correct maintenance environment by analyzing the outside temperature，PH，humidity，medium density，embedded environments effect on the range of electrodepotential; analyzing the matching technology of the non-polarizable electrode and signalacquisition part and making the corresponding test. Design of FIR digital filter，Averagemath module，overshoot removal module. To finish the filtering, mathematic average, andthe peak processing of the interference information, thus provide reference data for theoilfield development.Now the team is carrying out a research into other types of non-polarizable electrodepreparation work. To overcome the complex use of the environment, broadening theapplication fields, further improving the test precision of the electrode, extending theservice life, increasing the stability of electrode, designing more intelligent gatheringsoftware, using GPRS synchronization technology, realizing wireless sampling to replacethe cable, making the measured data get more precise data processing, further providingthe effective technical support for the development and utilization of the mineral oil.