Rotating Disc Acid Reaction System, CRS-100, is a computer controlled acid reaction system that allows for the controlled reaction of reservoir rock samples with acid fracture fluids and the timed sequential collection of reactant fluid. From the chemical analysis of the reactant and the experimental and sample collection data from the CRS-100 the reaction rates of carbonate and dolomite samples can be calculated and the results used in the design of effective acid stimulation treatments of wells. The CRS-100 features a 3,000 psig (21 MPa) pressure vessel as standard with a 1 in. rotating disc, magnetic drive system, temperature control system, fraction collector and data acquisition and control software. Pressure, temperature, acid displacement and test duration are software controlled. The software permits the collection of a number of reactant samples at preselected time intervals.