Working principle
The distillation tower achieves efficient separation of liquid mixtures through differences in component volatility. The core principle is a cycle of multiple partial vaporization and condensation:
Vaporization process: The bottom reboiler is heated to partially vaporize the liquid phase, and during the rising process of steam, light components (low boiling substances) are enriched in the gas phase.
Condensation process: The condenser at the top of the tower cools the steam into liquid, and heavy components (high boiling point) are enriched in the liquid phase. Part of the condensed liquid flows back into the tower to maintain mass transfer efficiency.
Counter current contact: Gas and liquid phases come into counter current contact on the surface of the tray or packing, and the components are separated step by step through mass and heat transfer, forming light component products at the top of the tower and heavy component products at the bottom of the tower.

Key operating parameters
Temperature gradient: from high temperature at the bottom of the tower (heavy component enrichment) to low temperature at the top of the tower (light component enrichment), strict temperature control is required for each section.
Pressure control:
Normal pressure: suitable for most conventional separations.
Pressure/pressure reduction: Adjust the boiling point to accommodate thermosensitive or high boiling point materials.
Reflux ratio:
Definition: The ratio of reflux liquid volume to extracted product volume directly affects separation accuracy and energy consumption.
Optimization: High reflux ratio improves purity but increases energy consumption, requiring dynamic adjustment to balance efficiency and economy.