Etching Crack Conductivity Tester Research And Experimental Research

Acid fracturing is an important stimulation technique for carbonate formation. The success of an acid fracturing treatment is determined by two characteristics of the fracture formed by the acid reaction.length of the conductive fracture and conductivity of the fracture.The distance that reactive acid moves along a fracture is controlled by thecompetition between the acid fluid loss and the rate of acid reaction with the formation versus the acid flow rate along the fracture.The final fracture conductivity is determinated by the material quantity which was solved by the acid and flowback and thedegree of irregularity.Above all,conductivity is more difficult to predict in the complex Reservoir which is high tempreture.low permeability and lie hidden deeply in the earth,then the evaluation is affected.Therefore,the research of fracture conductivity is necessary for enhancing the awareness of the carbonate formation acid fracturing and promoting the technology of the acid fracturing.At present, fracture conductivity apparatus have a common characteristic that the core is much long(between 17 and 40cm).However,the actual cores in the oilfield is too small to satisfy the request of apparatus. So the back or similarity core was choosed to modeling the formation,and the test result can't represent the actual condition of the formation.And the deviation of predicting the fracture conductivity was inevitably.In view of the above questions,designing and developing the apparatus of predicting conductivity for small gauge cores. And research the fracture conductivity of the cores from the LunNan Oilfield.The main achievements acquired in this paper lie in the following:Based on the fracture conductivity test philosophy,developing the apparatus which is fit for the small gauge cores.By this apparatus we can make exprement with the actual cores,the test result can modeling the ture reaction of the formation really and accurately,forecasting the changement of the fracture conductivity.Choosing surfactant Acid,gelled Acid and Emulsified Acid with the apparatus to modeling a great variety of the acid fracturing technology,and comparing the difference of the result of the conductivity and the acid etched form,guiding and selecting theoptimal technology.In virtue of the result of conductivity,analyzing synthetically all kinds of factors affecting the fracture conductivity for the carbonate reservoir,and summarizing the requirements to gain the high fracture conductivity for the carbonate formation.Analyzing and comparing the formulas to calculate the conductivity.On the base of N-K relational expression,taking account of the influence by acid filtration to evaluating the fracture conductivity.otherwise,based on both the surface roughness and the rock mechanical properties,a new fracture deformation model was derived to...