1. Reflux ratio of distillation tower is the core parameter of distillation tower operation. When the reflux ratio is too low, the gas-liquid contact is insufficient, and the nitrogen component cannot evaporate fully, resulting in a decrease in oxygen purity; If the reflux ratio is too high, it may cause liquid flooding and disrupt the distillation process. When the oxygen extraction amount is too large, the rising steam in the upper tower distillation section decreases, the reflux ratio passively increases, the nitrogen evaporation in the liquid phase is insufficient, and the oxygen purity decreases accordingly.
2. The operating pressure is inversely proportional to temperature, and the upper tower pressure is inversely proportional to oxygen purity. Excessive pressure can compress the gas phase space and reduce the efficiency of nitrogen oxygen separation; Pressure fluctuations (such as too low) can disrupt phase equilibrium and cause fluctuations in purity. The oxygen production temperature needs to be strictly controlled. Low temperature will increase equipment energy consumption and cost, but high temperature will reduce separation efficiency. When the main cold liquid oxygen level is too high, the evaporation resistance increases and the oxygen purity decreases.
3. The oxygen extraction amount and extraction rate should be matched with the processing air volume and nitrogen concentration. When the extraction amount is too large, the material balance is disrupted and impurities enter the oxygen product; If the extraction rate is too high, it will lead to a decrease in oxygen purity. When the oxygen extraction rate increases, the nitrogen content in the liquid phase increases and the oxygen purity decreases.
4. The argon fraction is proportional to the theoretical number of trays, oxygen content in the argon fraction, and oxygen purity. The higher the oxygen content in the argon fraction, the better the separation effect in the lower distillation section of the upper tower. The more theoretical trays there are in the upper and lower parts of the tower, the more complete the gas-liquid contact and the higher the oxygen purity.
