Application of Tracer Monitoring Technology in Production Wells

With the development of Daqing Oilfield, the conventional fracturing effect has become worse year by year. The oilfield developers propose fracturing and oil displacement technology. According to the different reservoir properties of the fractured reservoir, the amount of displacement fluid is designed. In order to evaluate the production capacity of each section after pressure, the tracer monitoring technology of production wells is proposed. During the construction of fracturing oil displacement test well, the tracer is injected into the construction well according to the specified concentration. After the well is opened, samples are taken to monitor the recovery concentration of the tracer in each fractured section. Combined with the production data of the monitoring well, the productivity contribution rate, liquid production, tracer production and recovery rate of each fractured section after fracturing are calculated quantitatively. The technique applies 10 wells, taking a test well group as an example, the total recovery rate of tracer is 59.29%, while the average recovery rate of monitoring logging is 32.23%, and the average recovery rate of adjacent well is 27.06%. It indicates that the far end of fracture flows to the adjacent well after fracturing, and the amount of displacement fluid in the near well is too much, which leads to the low production of fracturing well in the later period. Analyzing from the perspective of reservoir development, it is pointed out that the fracturing and oil displacement technology is not recommended for the layers with poor physical properties of the surrounding sand bodies and not connected. The tracer monitoring technology can be used to judge the liquid production capacity of different fracturing layers, and then evaluate the fracturing effect, which provides the basis for well and layer selection and reasonable design of fracturing operation scale.