Production Variance in Purified Carboxymethyl Cellulose (CMC) Manufacture

This study investigates the variance in industrial production of carboxymethyl cellulose (CMC). Initially it was thought that the product exhibited excessive quality variations. However careful viscosity and molecular weight distribution measurements on both the raw material and the final product, supplemented with online quality measurements, showed that the product variations were less severe than originally thought. The most probable reason for this unfounded quality concern is due to imperfect routine measurements coupled with a limited reporting of the subsequent offline laboratory analysis. The situation where the routine quality analysis plays as much a role in the uncertainty as the production itself is believed to be of general relevance for the chemical processing industries.