Application Of Nitrogen Bubble Acidification Process Technology In Jilin Oilfield

It is low pressure, low porosity and low permeability reservoir in Jilin Oilfield. With the progress of oilfield exploration, conventional acidification technique is unable to improve the low permeability effectively and hard to backflow, causing oil layer secondary pollution easily. Foamed acid is characterized by acid uniform distribution,priority to accessing into the oil layer, low density, low liquid-column pressure, high backflow, high carrying-ability, little damage to stratum, long distance of acid fluid effective penetration, simple construction procedure, and high economic benefits. With introduction of making nitrogen, nitrogen injection equipment and foam generator, in this paper, nitrogen foam acidification process technology was studied and verified experimentally in oilfield,The results shows that this technology induce to increase yield and economic efficiency obviously.With exploitation of Jilin oil and gas field to be in the middle-later stage,reservoir pressure is reduced, voidage formation is serious, which brings a lot of difficulties for stable and high yield of the oilfield, some conventional technical measures adopted by Jilin oil field can not meet demand of produce. Combined with the actual situation of Jilin oilfield, the acidizing and gas lift mainly exist the following problems:1, for the heterogeneous reservoir, acid will gives priority to the high permeability layer, but the low permeability can not improve effectively;2, for the oil-water layer formation, acid will give priority to enter the water layer, the water increase rapidly after acidification, oil yield decrease;3, for the low pressure oil well, flowback of residual acid is difficult after acidification, resulting in 2nd pollution easily, influencing acidification effect;Combining the character of foam liquid, Acidizing liquid and fracturing liquid effectively, forming a new working fluids, which can greatly improve the level of acidification, fracturing technology in Jilin oilfield, improve the success rate and efficiency entirely.