The low distilled water temperature is mainly caused by the multi-stage distillation process. A multi-effect distilled water machine uses a multi-stage distillation system in which multiple evaporators and condensers operate in sequence. Water undergoes repeated evaporation and condensation across each effect. Because each effect operates at a relatively low temperature, the heat input is distributed across multiple stages, and the final condensed distillate is discharged at a lower temperature.
This staged temperature design helps improve distillation efficiency and water purity. Lower operating temperatures in each effect reduce the risk of thermal degradation and impurity carryover, while allowing secondary steam to be reused more effectively. However, it also means that the outlet distilled water temperature is relatively low compared with single-effect systems.
For applications that require higher outlet temperatures, additional heat exchange components or post-heating sections may be needed. Non-standard condenser tubes, heat recovery preheaters, and outlet piping connections often have to be matched to the specific multi-effect layout. Hansheng Automation can provide drawing-based precision machining for these components, including single-piece and small-batch production, helping users adjust heat recovery performance without changing the original distillation structure.
In practice, the actual outlet temperature depends on the number of effects, cooling water temperature, operating pressure, and the condition of the final condenser. If the final condenser is oversized, fouled, or not properly matched to the sixth-effect or last-effect vapor load, excessive subcooling may occur and the distillate temperature may drop further. We can custom-machine replacement tube bundles, end covers, and adapters according to customer specifications to help restore proper thermal balance and maintain stable outlet temperature.
