The standard "ISO DIS 776-2010 Pulp, Determination of acid-insoluble ash" specifies a method for the determination of acid-insoluble ash content in pulp. Acid-insoluble ash mainly refers to minerals or inorganic residues that cannot be dissolved under acidic conditions, such as silicate and calcium sulfate, etc. The method calculates the content of the pulp by using acid to dissolve the soluble components after ashing the pulp sample, and then separating and weighing the remaining insoluble substances. The standard is applicable to various types of pulp and is one of the important means to evaluate the purity of pulp and its quality control. This method has high accuracy and reliability, providing a unified test benchmark for the paper and pulp industry, ensuring production mass and process optimization.