Abstract: The present invention discloses a novel high-temperature visual acid etching test device and method; the test device includes a visual rock slab holder, an acid solution storage tank I, an acid solution storage tank II, a heating apparatus, a high-pressure water pump, a low-pressure acid pump, a back-pressure valve, an acid valve A, an acid valve B, an acid valve C, an acid valve D, an acid valve E, an acid valve F, a water valve G, a water valve H, a water valve I, a water valve J, and a water valve K; both the acid solution storage tank I and the acid solution storage tank II are provided with a piston therein, where the acid solution storage tank is divided into upper and lower independent parts by the piston. According to the present invention, the flowing process of an acid solution in a fracture can be directly observed to accurately characterize the distribution of the acid solution in the fracture, which facilitates a study on an acid etching mechanism.

Abstract: The present invention relates to a three-dimensional acid fracturing method for carbonate reservoirs in long intervals, which sequentially comprises the following steps: S1: based on the distribution characteristics of porosity and permeability of the reservoir where the candidate well is located, the reservoirs are divided into Class I, Class II and Class III, and the required acid fracturing fracture density range ?ir of different types of reservoirs is determined according to the increase of production; S2: Determine the most economical fracture number Ne when the economic net present value NPV of candidate wells reaches the maximum in the fifth year based on interval length of different types of reservoirs in candidate wells and acid fracturing fracture density range ?ir determined by S1; S3: Determine the three-dimensional acid fracturing segmented fracture arrangement technology according to the completion mode of the candidate well and the most economical fracture number Ne determined by S2; S4: Based

Abstract: The invention introduces a method of calculating etching profile of acid-etched fracture system considering complex filtration media, which mainly considers dynamic filtration caused by natural fractures and acid-etched wormholes in acid fracturing, calculates the above filtration process by a numerical method, and finally calculates acid etching profile of acid-etched fracture system based on acid concentration profile. Calculation equations include fluid pressure in natural fractures, filtration velocity in natural fractures, fracture geometry of hydraulic fractures, fluid pressure in matrix rock, acid concentration profile in natural fractures and hydraulic fractures, acid etching width in hydraulic fractures and natural fractures, and length of acid-etched wormhole, etc.

Abstract: The invention introduces a method of calculating etching profile of acid-etched fracture system considering complex filtration media, which mainly considers dynamic filtration caused by natural fractures and acid-etched wormholes in acid fracturing, calculates the above filtration process by a numerical method, and finally calculates acid etching profile of acid-etched fracture system based on acid concentration profile. Calculation equations include fluid pressure in natural fractures, filtration velocity in natural fractures, fracture geometry of hydraulic fractures, fluid pressure in matrix rock, acid concentration profile in natural fractures and hydraulic fractures, acid etching width in hydraulic fractures and natural fractures, and length of acid-etched wormhole, etc.

Abstract: The present invention discloses a method for experimentally determining the conductivity distribution of an acid-fractured fracture a carbonate rock oil and gas reservoir, including the following steps: by an acid fracturing simulator FracproPT, simulating and acquiring distribution data of fracture width, fracture height, temperature and acid liquor mass concentration in a hydraulic fracture length direction; selecting fracture width, fracture height and temperature data of total 10 feature points with the acid liquor mass concentrations being from 100% to 10% of the initial mass concentration; converting site acid injection displacement into laboratory acid injection displacement; preparing experimental acid liquor according to the acid liquor mass concentration data of the 10 feature points; and simulating the acid etching process, and experimentally testing the conductivity under the condition of reservoir closed pressure, and drawing a distribution diagram of the acid-etched fracture conductivity in the

Abstract: The present invention discloses a method for experimentally determining the conductivity distribution of an acid-fractured fracture a carbonate rock oil and gas reservoir, including the following steps: by an acid fracturing simulator FracproPT, simulating and acquiring distribution data of fracture width, fracture height, temperature and acid liquor mass concentration in a hydraulic fracture length direction; selecting fracture width, fracture height and temperature data of total 10 feature points with the acid liquor mass concentrations being from 100% to 10% of the initial mass concentration; converting site acid injection displacement into laboratory acid injection displacement; preparing experimental acid liquor according to the acid liquor mass concentration data of the 10 feature points; and simulating the acid etching process, and experimentally testing the conductivity under the condition of reservoir closed pressure, and drawing a distribution diagram of the acid-etched fracture conductivity in the