The following factors affect the purity of oxygen produced by large and medium-sized air separation units: first, the purity of oxygen in liquid air is too low; second, the amount of oxygen taken out is too large; third, the liquid oxygen level of condensing evaporator is too high; fourth, the tray efficiency is reduced; Fifth, the distillation conditions are abnormal; sixth, the main cold building, when the condensing evaporator has poor brazing quality or evaporator tube wear or local explosion When a small local leakage is caused, it may lead to the leakage of high-pressure gaseous nitrogen to the low-pressure oxygen side, resulting in the reduction of oxygen purity.
