Production technology of alumina - Shanghai xin chemical industry
alumina, the appearance of white powder or granular, industrial production of alumina is made from bauxite, a market segment method commonly used in industrial production of aluminium oxide bayer process, sintering process and the combined method.a bayer process just like in the production of aluminum hydroxide method, is down to control the condition of different reaction direction. The bauxite in sodium hydroxide solution, make the alumina react with sodium hydroxide to generate partial sodium aluminate, with various impurities separated by mechanical means. Will generate partial sodium aluminate solution for low temperature processing, partial sodium aluminate solution temperature, the more the greater the degree of supersaturation of close to 30, to join aluminum hydroxide crystal in aqueous solution at the moment, will promote the partial hydrolysis of sodium aluminate, aluminum hydroxide can be produced. Mother liquid sodium hydroxide can be recycled. Then will be calcining aluminum hydroxide can be crystallized alumina. 2 sintering, the sintering process of alumina and aluminium hydroxide preparation of sintering process, will produce the calcining aluminum hydroxide, and evaporate the water, get alumina crystals or powder. triple legal the so-called joint method is bayer process and sintering process using the same time, can give full play to the advantages of two methods, get a better economic benefit. Joint method and can be divided into series and parallel method and mixture combination. the, can undertake choosing according to the composition of bauxite in, which can make full use of resources.