Multi-effect water distiller is the key equipment of the most widely used water injection preparation system. The multi-effect water distiller adopts high temperature and high pressure operation to ensure stable production of pyrogen-free water for injection. The distilled water produced by the multi-effect water distiller fully meets the requirements of the current US Pharmacopoeia, European Pharmacopoeia, and Chinese Pharmacopoeia on water for injection.

The raw material water is heated by the industrial steam in the first-effect preheater. After entering, the preheaters of each effect are heated by the secondary steam; the condenser is heated by the secondary steam and distilled water; then it is uniformly heated by the water separator at the top of the evaporator. Distributed into the evaporation tube, a film-like water flow is formed in the evaporation tube; these water flows are quickly evaporated because of their thinness, and secondary steam is generated; the raw water that has not been evaporated is transported to the next effect as the secondary effect evaporator The raw material water has similar effects in the future. The unevaporated water enters the next effect, and the water that has not been evaporated until the last effect will be discharged as condensate; the evaporated raw water is now secondary steam and continues to evaporate The vessel spirals upwards and enters the pure steam pipeline through the special separation device in the upper part, as the heat source of the secondary effect; the secondary steam is condensed into distilled water after the secondary effect absorbs heat; the process of each effect is similar to this, distilled water of each effect The secondary steam with the final effect is collected by the condenser, and after heat exchange with cooling water and raw material water, it is cooled into distilled water; after online conductivity detection, qualified distilled water is output as water for injection, and unqualified distilled water will be discharged.

 The secondary steam converted into raw material water is clean steam, which undergoes three separations: after entering the evaporator initially, it flows down the tube and evaporates at the same time. This is the first separation; the evaporated raw water (secondary Steam) is turned back 180 degrees at the lower end of the evaporator, and the impurities are separated to the lower part under the action of gravity. This is the second separation; the evaporated raw water, that is, the secondary steam, continues to spiral up in the evaporator to the middle At the upper special separation device, the third separation is carried out. The cooling water only passes through the condenser to cool down the distilled water produced by each effect and the secondary steam of the last effect. The industrial steam heats the raw water in the first-effect evaporator and preheater, and the heat is absorbed and discharged out of the machine as condensed water. In the condenser, there is a part of gas that cannot be condensed into water, called non-condensable gas. This part of the gas will be removed by the discharge device installed on the upper part of the condenser. Depending on the model, there may also be a continuous non-condensable gas discharge device on each effect evaporator