| In recent years, high-viscosity acid is more and more widely used inacid-fracturing.This paper defines viscosity of greater than20mPa·s acid as highviscosity acid. In order to correctly guide the design and optimization of acidfracturing and on-site construction, it is necessary to carry out the related simulationexperiment to obtain the acid-rock reaction kinetic parameter. Since different factorsin the acid-rock reaction （for example: rock type, temperature, pressure, acid nature） havedifferent effects on the reaction rate and kinetic parameters, therefore it is necessary tosummarize the influence of different factors on acid-rock reaction. However thecommonly used experimental methods in testing high viscosity acid acid-rockreaction rate showed such phenomenon as the same acid concentration or irregularchange, which led to a not systematic study of high viscosity acid acid-rock reaction.Chengdu University of Technology independently designed the different viscosityacid-rock reaction simulation equipment, which was used for testing high viscosityacid acid-rock reaction. On this basis, this paper firstly introduced the acid-rockreaction mechanism and the influencing factors of acid-rock reaction, commonlyused acid-rock reaction analog test methods and analysized and compared thenon-adaptivity of tested high viscosity acid. It also introduced the different viscosityacid-rock reaction simulation methods used in the experiment from designideas,works and installations, Analyzed the flow pattern of the acid in the reactor atdifferent velocity. Basised on this, this paper designed the acid-rock reactionexperiments with four kinds high viscosity acid system and seven different blockscarbonate in different acid concentrations, flow rates and temperature. Finally, basedon the analysis of the experimental data, this paper obtained the following laws of influence:（1） Different rock types have different reaction rate, rock mineral content hasexponential relation to the reaction rate: J=2×10-5EXP（-3.4983a）；In the kineticequation, different types of rock caused the main change of the reaction velocityconstant K, while reaction order m is essentially the same, K and the rock mineralcontent have power function relationship, gelled acid:K=7×10-7a-1.931, crosslinkedacid:：K=3×10-7a-1.963, the reaction velocity constant increases with the increasingof mineral content.（2） There is a power function relationgship between the acid viscosity and thereaction rate:J A B, the greater the viscosity of the acid,the smaller the reactionrate. The reaction velocity constant K and the acid flow index n have quadraticpolynomial relationship:K=1×10-5n2-7×10-6n+3×10-6the reaction velocityconstant K increases with increasing of the acid flow index n. The reaction velocityconstant K and the acid viscosity have logarithmic relationship:K=-1×10-6ln（μ）+7×10-6，the reaction velocity constant K decreases withincreasing viscosity. The Reaction order m and the acid flow index n have quadraticpolynomial relationship: m=1.2083n2-0.7076n+0.526, The Reaction order mincreases with increasing the acid flow index n. The reaction order m and the acidconsistency coefficient K have power function relationship:：m=0.499K-0.1228, thereaction order m decreases with increasing the acid consistency coefficient K.（3）The unit concentration rate of increment Jc and the acid flow index n haveexponent relationship: JC=5×10-7EXP（2.619n），The unit concentration rate ofincrement Jc increases with increasing the acid flow index n. The unit concentrationrate of increment Jc and the acid consistency coefficient K have logarithmicrelationship:JC=-1×10-6ln（K）+1×10-6，The unit concentration rate of incrementJc decreases with increasing the acid consistency coefficient K. |
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