{'fraction_non_alphanumeric': 0.01932367149758454, 'fraction_numerical': 0.004830917874396135, 'mean_word_length': 4.967078189300412, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
A New Method for Measuring Acid Effective Consumption Time in Acid Fracturing

In acid fracturing, the fast acid-rock reaction limits live acid penetration distance. Many kinds of acids were developed to reduce the acid-rock reaction rate. Acid effective consumption time in the fracure is a key factor for accurate prediction of live acid penetraiton distance in acid fracturing designs. In this paper, we developed a new method for measuring acid effective consumption time in the fracture and did experimental result matching to obtain effective acid diffusion coefficient with a acid flow-reaction model. Firstly, we designed a apparatus and corresponding experimental procedure. Then used the new method to measure the effective consumption time for gel acid and crosslinked acid. The new method uses reservoir core samples and is convenient to heat all the fluid as well as pipe lines to the reservoir tempeature, which reflects in-situ conditions more reliably. In the experiment, the rock mass loss with time was measured, based on which the acid consumption time is predicted. Under the experiment conditoins, the gel acid has a effecive consumption time about 17-minute, and the crosslinked acid has about 22-minutes at 130°. Finally, a model of acid flow-reaction in a fracture was used to match experimental results to obtained the acid diffution coeffecient. The results from this study help improve accuracy in acid fracturing designs.