fractional column的用法和樣例：
例句
- The liquid drawn off from the bottom of the first fractionating column, the primary fractionating column, is fractionated again in another column under low pressure.
從第一個分餾塔即初分塔底部下來的液體，再在低壓下進入其餘的分餾塔分餾。 - Water wash injections, typically continuous and low volume, are used to avoid salt build-up or reduce corrosiveness in the distillation column overheads.
水洗水注入設施，典型的是連續小量，避免結鹽或減緩分餾塔頂的腐蝕。
