Purification Technology Edition: Daily Question [2017-12-18]

The higher the reflux ratio, the higher the purity of the product at the top of the tower, but the yield decreases and more energy is consumed； Conversely, as the reflux ratio decreases, the purity drops while the yield increases relatively.

The purity of the distillation product, with a constant number of tower plates, depends on the reflux ratio. A high reflux ratio results in a higher purity of the gaseous product, while the purity of the liquid product is lower; conversely, a low reflux ratio yields the opposite outcome.

Increasing the reflux ratio can improve the quality of the product obtained from the top of the distillation column; however, it reduces the column’s production capacity and increases the consumption of water, electricity, and steam (heat sources). This leads to an excessive circulation rate of the material within the column, which may even result in flooding and disrupt the normal operation of the column. Nevertheless, the light components in the distillation section are purified, while the bottom of the column contains a higher amount of these light components. If the reflux ratio is too low, the liquid phase on the tower plates decreases, resulting in poor gas-liquid mass transfer. This causes the heavier components at the bottom of the tower to reach the top of the tower; in severe cases, this leads to substandard quality of the product at the top of the tower

The purity of the distillation product, with a constant number of tower plates, depends on the reflux ratio. A high reflux ratio results in a higher purity of the gaseous product, while the purity of the liquid product is lower; conversely, a low reflux ratio yields the opposite outcome.

A high reflux ratio can improve product quality, but it correspondingly increases the cooling load on the top condenser and the heating load on the bottom of the tower. A low reflux ratio can affect product quality.

Increasing the reflux ratio can improve the quality of the product obtained from the top of the distillation column; however, it reduces the column’s production capacity and increases the consumption of water, electricity, and steam (heat sources). This leads to an excessive circulation rate of the material within the column, which may even result in flooding and disrupt the normal operation of the column. Nevertheless, the light components in the distillation section are purified, while the bottom of the column contains a higher amount of these light components. If the reflux ratio is too low, the liquid phase on the tower plates decreases, resulting in poor gas-liquid mass transfer. This causes the heavier components at the bottom of the tower to reach the top of the tower; in severe cases, this leads to substandard quality of the product at the top of the tower

It is said that this can improve product quality, but it requires reducing the tower’s production capacity and increasing the consumption of water, electricity, and steam (heat sources). This leads to an excessive circulation rate of the materials inside the tower, which can even result in flooding and disrupt the normal operation of the tower. However, the light components in the distillation section are purified, while the bottom of the tower contains a higher amount of these light components. If the reflux ratio is too low, the liquid phase on the tower plates decreases, resulting in poor gas-liquid mass transfer. This causes the heavier components at the bottom of the tower to reach the top of the tower; in severe cases, this leads to substandard quality of the product at the top of the tower

It is said that this can improve product quality, but it requires reducing the tower’s production capacity and increasing the consumption of water, electricity, and steam (heat sources). This leads to an excessive circulation rate of the materials inside the tower, which can even result in flooding and disrupt the normal operation of the tower. However, the light components in the distillation section are purified, while the bottom of the tower contains a higher amount of these light components. If the reflux ratio is too low, the liquid phase on the tower plates decreases, resulting in poor gas-liquid mass transfer. This causes the heavier components at the bottom of the tower to reach the top of the tower; in severe cases, this leads to substandard quality of the product at the top of the tower

During operation, the quality of the product is ensured by adjusting the reflux ratio. When the content of heavy components in the tower top distillate increases, it is common to increase the reflux ratio in order to reduce these heavy components and ensure that the product quality meets the standards. When the light components from the distillation section move down to the stripping section and cause the temperature at the lower part of the tower to drop, the temperature there can be raised by appropriately reducing the reflux ratio. Increasing the reflux ratio can improve the quality of the product obtained from the top of the distillation column; however, it reduces the column’s production capacity and increases consumption of water, electricity, and steam. An excessively high reflux ratio will result in an excessive circulation rate of the material inside the tower, and may even lead to flooding, disrupting the normal operation of the tower.

Increasing the reflux ratio will raise the concentration of the light components at the top of the tower, improving their quality.