Experimental Research On Gas Mixing Flooding Technology To Improve Steam Flooding Effect

China is suitable for steam drive mining reserves of about 450 million tons,At present in Xinjiang,Liaohe application of steam flooding technology development of heavy oil reservoirs have entered a later stage,the output decline quickly,the economic benefits of deterioration,to maintain stable production is facing severe challenges,urgent need to solve the vertical and plane flow steering problems,such as Liaohe Oilfield This is the case with the production of the 40-block steam flooding test block,To this end,it is proposed to add a mixture of air,nitrogen and other gases in the steam to convert the displacement medium from a single steam into a non-condensable gas and steam to improve the steam flooding and volume,oil displacement efficiency and thermal efficiency.Improve the efficiency and recovery of steam flooding.In this paper,we can see that the steam flooding and nitrogen addition can make the steam feed front become relatively uniform,and the steam wave and volume are expanded to a certain extent,which increases the utilization rate of heat and makes the development effect better.When the mass ratio of steam to nitrogen is 32: 3,the effect of compound flooding is the best.If the crude oil recovery rate is taken into account,the steam-air blending ratio is optimal for 32: 3;if the cost problem is taken into account,the steam-air ratio increases from32: 2 to 32: 3 Small,so should consider the cost of air to determine the cost of steam ratio.The air-assisted steam flooding study was carried out at 17 ° C,17-24,25-K35,13-024,6-K032 and 5-K033 wells.The results show that the use of steam ratio of about 1:70(t / d)/(Nm3 / d)(this result is consistent with the indoor experimental conclusion),mixed with normal temperature air assisted steam drive can be achieved on the whole Mining effect.The average daily production of 5 wells in the five test wells increased from 14.8 t / d to 16.1 t / d,and the oil / gas ratio increased from 0.13 to 0.17 in the past.The production characteristics of the test bed group show that the continuous injection of air-assisted steam flooding can keep the vapor leading edge stable.The slug injection method is used to reduce the volume of the steam chamber after the steam is stopped,resulting in the shrinkage of the steam chamber.Steam continuous injection method to maintain the stability of the steam chamber expansion,you can get a better development effect.Therefore,the addition of air-assisted steam flooding should be continuous injection method.Moreover,the design of a reasonable amount of air daily injection to ensure that the air-assisted steam drive a good effect is very important.In this paper,through the field of gas-assisted steam flooding test of the 17-028 well group,it was found that the nitrogen content of the original steam drive increased rapidly from 4% to 61% in the dominant direction of the initial steam drive,and then remained unchanged at the same time.The oxygen content increased from 0.94% to 1.5%,and later decreased to 0.87%,accompanied by the wellhead temperature from 77 ? to 89 ?;that the injection of air to the direction of the preferred direction of steam flooding,and the air in the oxygen and crude oil A low temperature oxidation reaction occurred,resulting in reduced oxygen content in the reservoir,to avoid construction safety problems,but also to the oil layer temperature has been increased.The results of this study are of great reference significance and practical value for the effective development of Qi oil block and its similar heavy oil reservoirs.