Optimization And Early Warning Of The Lifting Technology With Hot Liquid Cycling Within The Double Hollow Rod Pumping Well

The lifting technology with hot liquid cycling within the double hollow rod pumping well is one of the rencently developed heavy oil production technology,widely used in steam huff and puff wells.Yet the lack of its theoretical research,lift technological design optimization method and theory of early warning methods affect its lifting effect.To solve these problems,system analysis method is used to constructs the optimization model of technology with hot liquid cycling within the double hollow rod pumping well,especially to establish the liquid temperature distribution either the axial heat was concerned or not concerned,force model of the double hollow rod,early-warning model based on the safetiy target and the determination of the limits of the cycling parameters.A calculating software is also made.The results show that the liquid temperature distribution concerned axial heat cannot have analytic solutions,and the effect of axial heat can be ignored in the common consequences.As a result,temperature distribution without axial heat concerned is applied.Chenjiazhuang oilfield 4 wells to calculate return temperature for the average relative error is 1.89%,oil output liquid temperature is 3.73%,the temperature model has high accuracy;the average relative error of the maximum load is 4.795%,the average relative error of the small load is 7.39%,the average the maximum load and the minimum load of the relative error is within 10%,meet the requirements of precision engineering calculation;the early-warning model to calculate critical thermal parameters of liquid Chengnan 91-H29 well as the value of the output oil’s temperature of 77.9 DEG C,mass flow rate of liquid circulation of 41.7t/d and the liquid injection temperature of 102.6 DEG C;the early-warning model to calculate critical thermal parameters of liquid Chengnan 91-H8 well as the value of the output oil’s temperature of 89.6 DEG C,which means the well is not work safe,to make it safe,the mass flow rate of liquid circulation should add to 41.7t/d or the liquid injection temperature should add to 102.6 DEG C.