Ground real-time monitoring on sand production of heavy oil reservoir

With lower rock strength, loose sandstone heavy oil reservoirs are susceptible to sand production. To maintain peak production over a long term, it is necessary to monitor sand production in real time. A real-time sand-production monitoring system suitable for heavy oil reservoirs has been developed based on techniques for monitoring vibration signals, in which an independent acceleration detector is used to detect vibrations induced by collision of sand particles on pipe string. Through filtering, time domain analysis, frequency spectrum analysis and power spectrum analysis of relevant signals, the relationship between signal features and sand production has been found out to realize monitoring of sand-production of oil producers in real time. Lab tests were performed to test the performance of the monitoring system by changing granularity of sand grains, sand content, water cut, flow speed of flow medium, and using diesel and water as flow media. The test results show the system can detect sand grains of 44 μm in size at flow medium viscosity of less than 250 mPa·s. The monitoring system has been used on 8 wells. The test results show the monitoring results of the system are quite consistent with actual production performance of the oil producers. The newly developed real-time monitoring technique for heavy oil reservoirs can improve management of oilfields.