MASS TRANSFER MODEL, SOME FEATURES OF THE TECHNOLOGY AND THE MAIN PARAMETERS OF THE APPARATUS FOR THE REGENERATION OF NITROCELLULOSE POWDERS

Abstract

The stability of nitrocellulose plays a decisive role in determining its service life. As a result of physicochemical processes of interaction of nitrogen and its compounds with chemical elements and compounds found in the environment, nitric and nitrous acids have a negative effect on nitrocellulose. This is due to the drop in its energy value. An analysis of the studies showed the possibility of restoring the properties of nitrocellu- lose-based powder charges by treating them with hydrogen peroxide. However, the process of regenerating powder charges on an industrial scale to obtain the best effect is not given. Material balance equations and a molecular diffusion mass transfer model are presented. To assess the degree of hydrogen sorption by nitrocellulose, an indicator has been introduced - the reagent utilization factor. It shows what part of the peroxide of the substance for this concentration has joined the nitrocellulose. Factors influencing the energy characteristics of nitrocellulose are presented. It has been determined that at the longest stage of the life cycle of nitrocellulose powders - the storage stage, the main factors determining the resistance of gunpowders are: their composition, the quality of the starting materials, the production method, impurities in the gunpowder, storage conditions. It is indicated what changes and processes occur in the nitrocellulose layers of powder elements. The process of nitrogen mass transfer from the deep layers of the powder element to its surface by molecular diffusion is considered. As part of the complex problem of operating powder charges, a mathematical model of diffusion mass transfer is considered to determine the nitrogen content depending on time and taking into account the influence of storage temperature. This model is of practical interest for creating an industrial apparatus and determining its main design dimensions and performance. Based on the results of the experimental study, the mass transfer coefficient and the surface area involved in the regeneration process were determined. A diagram of the technological process for regenerating nitrocellulose powder charges and the design elements of the apparatus are presented.