Analysis of working principle and cleaning method of multi-effect distilled water machine

The multi-effect distilled water machine is a distilled water production equipment which uses deionized water as raw material water and is heated by steam. The distilled water produced by this equipment is stable in water quality, high in purity and free from pyrogens. It is currently the key equipment for the application of Zui for a wide range of injection water preparation systems. The multi-effect distilled water machine is operated at high temperature and high pressure to ensure stable production of pyrogen-free water for injection. The distilled water produced by the multi-effect distilled water machine fully meets the requirements of the current US Pharmacopoeia, the European Pharmacopoeia, the Japanese Pharmacopoeia and the Chinese Pharmacopoeia for water for injection.

Analysis of cleaning methods for multi-effect distilled water machine:

(1) For boiler scale, sulfamic acid (NH2SO2OH) can be used. When used, it is prepared into a cleaning solution with a concentration of 1% using deionized water. The pH value is between 1 and 2 and heated to about 60 °C. Phosphoric acid (H3PO4) can also be used. In use, it is formulated into a 2% concentration cleaning solution with deionized water and heated to about 65 °C.

(2) For silica scale, ammonium difluoride (NH4HF2) may be used, and the solution is prepared by using deionized water to a concentration of 1.5%, and heated to 50 ° C ~ 60 ° C. It can also be prepared with sodium hydroxide + anionic active agent to prepare a cleaning solution with a concentration of 10% and heated to about 60 °C.

Key words: multi-effect distilled water machine, falling film evaporator, pure steam generator, chamber filter press