Doubts regarding the renovation of the company’s methanol distillation unit

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I would like to ask the experienced colleagues at Haichuan: our company currently intends to modify the existing batch-type, atmospheric-pressure single-effect methanol distillation unit and convert it into a continuous-type, negative-pressure distillation system. Our material to be distilled is an aqueous solution of methanol at 40% concentration and formaldehyde at 5% concentration. The heat source for distillation is saturated steam, with a steam pressure of 3 to 4 kilograms. The distillate at the top of the tower is required to be a methanol aqueous solution with a concentration of 93%, while the distillate at the bottom of the tower is to be a formaldehyde aqueous solution with a concentration of 10%. All produced fluids must be recovered and reused. The temperature at the top of the tower is between 65 and 70 degrees, while the temperature at the bottom of the tower is around 80 to 90 degrees. Our condenser uses circulating water for cooling, and its heat exchange area is approximately 100 square meters. Our column reactor is a 3-t capacity unit, meaning it can perform batch distillation on 3 tons of material at a time; it currently takes 3 to 4 hours to complete the distillation process for one batch. The column is about 14 meters tall and uses corrugated packing. Today, the boss brought a technician to provide guidance. In his view, the normal-pressure distillation of methanol is slow and resource-intensive, and it is completely unnecessary; especially since the distillation of methanol we carry out is a type of rough distillation that does not require a high degree of separation – only ensuring the desired concentration of the product is sufficient. Using negative pressure distillation **improves efficiency, increases production, and reduces steam consumption – it’s perfect. I read in books that the production capacity of vacuum distillation is lower than that of atmospheric and pressurized distillation, but from the perspective of these technicians, it seems to make sense as well. After all, the boiling point of methanol isn’t that low; cooling it with water to below 60 degrees turns it into a liquid. Also, our tower is assembled by tightening multiple bolts together; the connection method is similar to that of flanges, with gaskets in between. Could anything go wrong if this type of tower is directly modified into a negative-pressure tower? Methanol is flammable and explosive; I think the current sealing of the tower simply cannot ensure no leaks. If a leak occurs, it would represent a serious safety hazard. Is such a modification reasonable? I’m asking everyone for help to make a judgment for me.