Studies On A Blocking Agent Called Micro-coil For Oil Well Of Low Production

Oil wells of low production may have undue water shutoff situation exist. And the benefit of the well water shutoff is becoming less and less, so we need to develop a blocking agent which costs less.In this paper, we have studied the blocking agent optimization, water shutoff mechanism, and water technology of micro-coil for oil well of low production. After the researches of the polymer's basic nature, HPAM is choosed as anion micro-coil; and cationic polymer as cationic micro-coil. In this paper, the torque balance is used to study the possibility of micro-coil formation of the accumulation of membrane. Experiments show that the micro-coil in the core can form multi-layer adsorption, which is called membrane accumulation. The material balance method is used to determine absorption capacity of micro-coil. The results is that: In 0 ~ 2000mg / L range, with the concentration of micro-coil increased, micro-coil adsorption on quartz sand increases. The static adsorption of cationic micro-coil is 909.091ug/g, and dynamic residual volume is 20.615ug/g. As while the static adsorption of anionic micro-coil is 123.457ug/g, and dynamic residual volume is 5.6806ug/g. Application performance of micro-coil is studied on core flow test. First, inject of anion micro-coil into core with penetration rate of 2um2,then inject cation micro-coil;So repeatedly inject 6 times. Interval slug is 2 pore volume. At this point, blocking effect is best. Micro-coil on the water flow resistance is 5.315 times of oil flow resistance, which proves that micro-coil has a good role in the selective blocking between oil and water. The twin-tube test is used to study on micro-coil performance of enhanced oil recovery. Experiments show that the micro-coil has a good performance of enhanced oil recovery, with value-added recovery of 8.2%.According to the test results, T211 of the Shuanghe oil field is choosed as well of construction. And perpetrate the construction method.