Research And Application Of Injection And Production By Stratified Layers On Horizontal Well For Heavy Oil Thermal Recovery In Liaohe Oilfield

Focused on practical production of horizontal wells for thermal recovery of heavy oil in Liaohe Shuguang oilfield,studies on stratified oil production and steam injection,multifunctional optional injection and production,associated oil production strings and so on were performed.The main research findings include:Firstly technologies of stratified injection for horizontal wells were researched,compound optional steam injection strings and associated tools were designed.Technologies of optional steam injection were employed,which were implemented within 65 wells,effective rate was nearly 100%,and average increased oil production for each well was 254.8 t,the rate of invest and return was 1:14.Then,technologies of stratified production for horizontal wells were researched,specific production strings were designed,and technology schemes were optimized.Third,compound optional injection and production strings for horizontal wells and associated underground tools were designed,which concentrated on double-acting packers of heat and cold.And other tools include: blasting valve,steam distributing valve,wire plug,telescopic tube,heat insulation pipe and oil pipe.Finally,multifunctional production strings of thermal production for heavy oil were designed,and facilitating conditions were created for implementation of various assistant measures such as plug-release,cleanup,injecting CO2 and so on.In the practical applications of plug-release of stratified layers for Shu 1-40-052 well,and cleanup of optional injection of CO2 and N2 for Shu 1-38-045,production efficiency was largely improved.In practical applications,our research results efficiently solved contradictions of unequal production for horizontal wells,and problems of high water content for partial horizontal wells,which largely improved total effects of production for horizontal wells in Shuguang oilfield.