%A LUO Litao, XIAO Hanmin, LIU Weidong, SUN Linghui, LI Jiye, GOU Feifei %T The Suspended Particles in Reinjection Sewage of Ansai Low Permeability Reservoir %0 Journal Article %D 2014 %J Science & Technology Review %R 10.3981/j.issn.1000-7857.2014.15.010 %P 69-72 %V 32 %N 15 %U {http://www.kjdb.org/CN/abstract/article_11672.shtml} %8 2014-05-28 %X The suspended particles in a reinjection sewage might plug the reservoir and reduce the permeability. This makes it difficult for the Ansai low permeable oil field to inject water and produce oil at present. In order to improve the effect of water flooding, a reasonable index of suspended particles for Ansai oil field has to be determined. For this purpose, five different particle sizes are considered with three different suspended particle concentrations in the Ansai natural core flow experiment. The results show that the permeability of the cores is reduced slowly with the increase of the injection of the suspended particles. When the injection reaches a certain amount, the permeability tends to be a stable value for a long time. When the concentration ρ>2 mg/L, the permeability is reduced more than 30%; when ρ≤1.0 mg/L and the particle size d<0.730 μm, the permeability is reduced less than 30%; when 1.0 mg/L<ρ< 2.0 mg/L and d<0.730 μm, the two factors act together, the permeability may be reduced more or less than 30%; when 0.730 μm≤d≤ 2.100 μm, the permeability is reduced more than 30%. It is therefore suggested that the range of the suspended particle size should be limited and stay away from the throat size of the reservoir in the water injection process. ρ<1.0 mg/L and d<0.730 μm for the Ansai low permeable oil field.