Study On Retention Of Hydroxypropyl Guar Gum To Porous Media Consist Of Ceramsite

Hydraulic fracturing is an indispensable means of reservoir reconstruction for efficient development of tight oil and gas reservoirs.The components of the polymer that is used in the process of fracturing will be retained in the propping belt with micro pores,which influences the conductivity of propping belt seriously.So it is necessary to pay attention to the cleanliness of the cracks.But there is no researcher to start with the interaction between the gelatinizer and the ceramsite,and to put forward the measures to reduce the damage.Therefore,it's necessary to carry out a systematic study on the mechanism of reservoir retention damage.This thesis used porous media consist of ceramsite as subjects for this study.Based on accurate measurement of retention amount of HPG,the experiments analyzed the retention amount variation with HPG concentration,Pore size distribution and solution temperature.The experimental results show that the amount of retention increases with the increase of the concentration of the solution,and increases with the decrease of the size of the ceramsite.When the temperature of the solution increases from room temperature to 90 ?,the amount of retention increases first and then decreases sharply.The micromorphology of HPG on the surface of ceramsite is mainly in the form of thin membrane and chain.The permeability damage degree of the HPG to the propping belt was tested by the dynamic displacement test.The change law of damage degree and the reduction of the permeability with the concentration of the solution and pore size distribution were analyzed.Based on the analysis of the floc morphology and the pore structure of the propping belt,the result showed that the relative size between HPG particle size and pore size distribution is the main reason of mechanical trapping.It's cognizant of HPG retention to the blockage of the inner pore throat of the propping belt by low field NMR.The effect of hydroxypropyl guanidine on the experimental parameters is clarified.The effect of loss rate of permeability on the experimental parameters is clarified,when fluid flow rate increased from 3mL to 6mL on the experiment condition,permeability damage obviously increased.The greater the flowback time or gas rate is,the smaller permeability damage is.It's found in propping belt there is a top strength limit of HPG plugging.The blockage is mainly due to the aggregation of the molecular chain by the hydrogen bonds between the HPG.The use of hydrogen bond inhibitors or surfactant can improve the extension property of the molecular chain of HPG.Block remover one and Block remover three can reduce the permeability damage of the propping belt by 7%and Block remover two can reduce damage by 10%.