Brine Treatment Choice In The Modern Salt Industry

Salt, a necessity of life and an important industrial chemical, plays an important role in national economy.Salt mainly comes from seas, wells and lakes. In respect of the producing method , refined and high unmixed salt is usually made by multiple effect evaporation in vacuum, when man-made bittern is needed. And in Pingdingshan 300,000-ton salt factory, it is gotten by developing rock salt through welling-drilling aqueous fusion. If measures were not taken to make salt using original bittern in evaporation pan, dirt would occur and thus both the quality and quantity would be lowered for the bittern used here is gypsum-typed. To solve this problem, the factory has been using gypsum seed crystal, that is, keeping gypsum within 20-50g/l by controlling reflux liquid proportionally. And in this way, we can get refined salt meeting physical and chemical target. But unfortunately, it is below standard as high-purified industrial salt. Thus, Pingdingshan Haolong Corporation Limited, has annexed Ting He Salt Factory, Ye County, specializing in making high-purified salt on the promise of purification of bittern.Since original bittern contains Ca2+, Mg2+ , SO42+etc, we should purify it by way of BaCl2-Na2CO3-NaOH.The key to removing impure ion from bittern is to define each purifying control point and to choose a most suitable purifying way. After doing alot of experiments, we find it better to define how much decontaminating agent we should put to the real impure ion in bittern. First, putting barium chloride and sulfate radical in the ratio of mole 1:1. Second, delimiting the excessive quatum of sodium carbonate in 0.5g/l and sodium hydroxide in 0.2g/l.For there are some problems such as too much equipment, covering too many areas, high power consumption, low speed of purification and incomplete sediment filtration etc, when we dispose of bittern by the traditional technique, we have used GORE film to purify bittern and have achieved a better result. Firstly, the purifying time is more than ten times shorter than before. Secondly, the quality of bittern has been greatly improved. For the impure ion in the original bittern can be scavenged and the solid phase impurities are made so few (SS Img ) as to stop dirt being produced in evaporation equipment, while both the quantity and quality of salt can be improved. Finally, a lot of money has been saved. The investment to purify bittern in the new technology is about 4 million yuan less than that in the traditional one. What's more, the profit and output is much higher than before.It is greatly significant both in theory and in reality that different measures are taken to process bittern on the basis of the different uses of salt. For not only the product quality are guaranteed but also the production costs are reduced.