Study On The Identification Of Dominant Channel And Countermeasures In HongQian-1 Well Area

During the steam injection thermal recovery process of heavy oil reservoirs in the HongQian-1 well area,due to the influence of geology and development factors,it is easy to form a dominant channel,resulting in frequent occurrence of steam explosion,and it is necessary to identify and adjust the dominant channels in order to control steam explosion and improve the development effect.This paper uses rank correlation coefficient identification,grey correlation degree identification and fuzzy comprehensive identification methods to study the dominant channel in HongQian-1 well area and identify the well groups that urgently need to adjust the plugging and need to adjust the plugging.On this basis,a high-temperature plugging agent was developed and evaluated the properties of the plugging agent,and the gelation mechanism of the plugging agent was discussed.This article has achieved the following results and understanding:(1)The dominant channel was identified by rank correlation coefficient,grey correlation degree and fuzzy comprehensive recognition.The identification principle was analyzed and the evaluation criteria were determined.The tracer data verified that the comprehensive error was 6.25%at most.Through analysis of the production wells of the hTD1005 well group,the advantage channels identified by the three methods are not the same.To make the recognition result more accurate,the entire encryption area is identified by three methods and the plane of the dominant channel is drawn.The results show that the dominant channel is more developed in the southwest.(2)In order to facilitate the treatment of the dominant channel,the well groups developed in the dominant channel were screened,and the three types of plugging were selected according to the urgent need of plugging,the need and no need of plugging.The screening results show that the hTD1006,hTD1013 well group has a high degree of development of the dominant channel and urgent need to adjust the plug;hTD1005,hTD1007,hT1014,hT1019,hT1027 well group need to adjust the plug;hT1012,hT1020,hT1021,hT 1026,hTD 1028 well group does not need to adjust blocking.(3)Through formula screening,formulas for high-temperature tannin extract systems are obtained:6.0g/L of tannin concentration + 2.0%of crosslinking agent concentration + 500mg/L of stabilizer concentration + 600mg/L?900mg/L of regulator concentration + 100mg/L of oxygen scavenger concentration,the gelation time is 11h?25h,and the gel strength is above H level.It can be adjusted according to the actual requirements on site.When the tannin extract system was aged at 250? for 60 days,the system was dehydrated in a small amount,indicating that the system had good aging stability.Under the conditions of water mineralization degree of different multiple layers,the gelation time and strength remained basically unchanged.which shows the system has good salt resistance under reservoir conditions;the gelation effect of the system under different pH conditions indicates that the suitable pH is 6-10.(4)The injection pressure of the silicone system is small,indicating that the tannin extract system has good injectability;when the amount of the silicone system reaches 0.5PV,the plugging rates of the three sand filling tubes with different permeability are all above 97%,indicating that the tannin extract system has good plugging performance;After injecting different PV systems,the plugging rate of the sand filling pipe remains unchanged after the previous increase,and the appropriate PV number is 0.3PV-0.5PV;when the continuous steam floods 6 PV,when the 6PV was flooded continuously with the steam,the plugging rate of the sand filling tube could still reach 92.7%,indicating that the tannin extract system had good erosion resistance;the experiment of improving the steam absorption profile showed that the steam absorption of the two sets of parallel sand filling tubes was sufficient.The profile improvement rate is above 90%,which indicates that the tannin extract system can effectively improve the steam absorption profile.