Optimization Design Research Of Calcium Hypochlorite Produced By Sodium Method

Calcium hypochlorite,as a main component of bleaching powder,is widely used for strong stability,fewer impurities,and convenience to use,transport and store.Domestic traditional production of calcium hypochlorite applies Calcium Process,which has a great impact on yield and environmental protection with a series of disadvantages,such as low effective chlorine,irregular shape,high residue,and untreatable waste liquid.Sodium Process is not developed in China since this technique is subject to constraints from foreign companies.This paper compensates the shortcomings of Calcium Process by addition of sodium hydroxide.This study on the production of calcium hypochlorite by Sodium Process will provide data and results for industries.According to the Sodium Process,optimal production conditions for calcium hypochlorite were obtained by using analytical and technical grade raw materials,respectively.The reaction temperature is 40 ? while the concentration of NaOH is 30%.Due to the presence of some products in the mother liquor,a recovery process can be used to reduce costs.Then an amplified experiment was carried out in the scale of 2.5kg along with recycling of mother liquor.The recycling of mother liquor could saving costs about 5%.A Calcium Process of a company in Xiqing District was modified based on the experiments through pulp,chlorine substitution,blending,drying and etc.The results indicated continuous and stable production,significantly increased effective chlorine,which is above 60%,significantly reduced impurities,formation of crystalline granular products,and greatly reduced waste emissions.Analysis of the results reveals the Sodium process overcomes the deficiencies of the Calcium Process,receiving stability of products,higher effective chlorine,lower impurities,granular products,greatly reduced residue,convenient recovery of mother liquor,and highly relieved environmental pressure.The results of this paper provides theoretical and experimental basis for the industrialization of production of calcium hypochlorite.