How three-column distillation improves the feed to the pre-distillation column and increases distillation output
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Our facility uses three-column distillation, with a designed methanol production capacity of 150,000 tons per year; it was designed by Saiding Company. The designed feed rate to the pre-tower is 28.8 m3/h; at present, we keep the feed rate to the crude methane column at 28 m3/h. If the feed rate is increased further, a high differential pressure will occur in the pressure column, resulting in inferior distillation products. What could be the reason for this? Currently, the distillation columns used for extraction in atmospheric pressure systems are larger than those in pressurized systems; according to design principles, it should be the pressurized columns that are larger. How can this be adjusted without affecting operational performance? Could everyone please help analyze this and suggest ways to optimize it? Thank you
As a supplementary note, we use a combination of sieve plates and packing in all three towers.
As a supplementary note, we use a combination of sieve plates and packing in all three towers.
As a supplementary note, we use a combination of sieve plates and packing in all three towers.
Could you let me know which parameters become unacceptable when the pressure tower is operated under increased load? ? Generally, distillation designs include a considerable margin of safety. Have you consulted the design manufacturer? ?
I asked for advice, and they said that the designed production capacity has been reached; it’s mainly the change in pressure difference that prevents further increases
When the pressure difference is high and there is no sign of flooding, it indicates intense mass transfer within the tower; at such times the gas density is high. Excess production occurs mainly due to issues related to material flow, heat transfer, and gas-liquid equilibrium. Generally, by maintaining an appropriate reflux ratio, the moisture level can be kept under control. As for the increase in pressure difference, it is a natural consequence of gas-liquid equilibrium, so there’s no need to worry excessively. If the pre-treatment tower can handle the process properly, then with proper control of parameters such as temperature, liquid level, and reflux ratio in the other two towers, high-quality product will definitely be produced.