Abstract:

It is often necessary to use acid and alkali to participate in the reaction in chemical production.The consumption of acid and alkali not only increases the production cost，but also discharges the waste residue or liquid containing acid and alkali，which endangers the environment.Ammonium（ammonia） circulation process can be employed as an effective method to solve the above problems.In the ammonium（ammonia） circulation process，ammonium（NH₄⁺） reacts with certain materials and converts into ammonia（NH₃）；then ammonia reacts with the materials and reconverts into ammonium，and the obtained ammonium（ammonia） is recycled.After the ammonium（ammonia） circulation reaction，the product is obtained.However，the ammonium and ammonia are recycled in the process without discharge，which is recycled in the process to form a closed loop.It not only avoids the consumption and emission of acid，base and other substances，but also can achieve theoretically a 100% utilization rate of reacted atoms in some cases.Because the ammonium（ammonia） circulation process is green and envitonment-friendly and can produce high value-added products，it bears very high industrial application value.Ammonium（ammonia） circulation process has shown unique advantages in the preparation or extraction of soda ash，calcium carbonate，alumina oxide and magnesium hydroxide.Some applications of ammonium（ammonia） circulation process in chemical industry field were introduced，which was expected to provide reference for the promotion of this process in the production of more products.

Key words: ammonium circulation, ammonia circulation, ammonia evaporation, gaseous ammonia, ammonia soda, environmental friendly