Optimization And Improvement Of The Purification Process For Sodium Carboxymethyl Cellulose

Sodium carboxymethyl cellulose(CMC)is a cellulose derivative with ether structure.The aqueous solution of CMC has functions of thickening,bonding,filming,emulsification and suspension,and it is widely used in washing,food,coating,textile,petroleum,medicine,ceramics,toothpaste,etc.,known as "industrial monosodium glutamate".In this study,the purification process of a CMC factory in Guangdong was analyzed based on the process data,some bottlenecks of the process,such as high consumption of washing solvent,inaccurate solvent concentration control,high energy consumption and low product purity,were discussed.Based on the reliability analysis of the purification equipment and purification capacity of the current process,the optimization of energy consumption and improving product purity was conducted.Firstly,the filtration and washing process of CMC slurry were experimentally studied,the basic parameters needed for technical improvement were obtained,and the washing process was optimized with focus of reducing the washing ratio and the energy consumption and improving the product purity.Then combining the advantages of filter cake displacement washing and reslurry washing,the retrofit scheme was optimized.Finally,the purification equipment was upgraded according to the optimized process parameters.The optimized retrofit was finally implemented,results showed that the energy consumption of CMC purification was reduced by 37%,and good economic benefit was obtained.This purification process improvement has advantages in process automation control,product purity control and low solvent consumption,which would be helpful for the CMC manufacturing process.