The automatic valve failure will reduce the purity of the backflow gas in the switching heat exchanger, while the forced valve failure will only affect the purity of the backflow gas out of the unit. It can be judged by testing the changes of gas purity in front of the automatic valve, before and after the forced valve.If the compression pressure of liquid oxygen is higher than the critical pressure (for example, the oxygen pressure for chemical industry is 6.0MPa or higher), there is no gasification stage with constant temperature in the gasification process of heat exchanger. This will affect the heat transfer performance of high-pressure heat exchanger, which should be fully considered in the design.Friction or local pressure rise; 4) the existence of substances with strong chemical activity (ozone, nitrogen oxides, etc.) increases the sensitivity of explosion. The harmful impurities in the main cooler are acetylene, hydrocarbons and solid carbon dioxide. They can enter the main cooler with the air flow at any time.
Air separation plant.Where the liquid layer is thin, the resistance is small, the amount of steam rising from the small hole is more; where the liquid layer is thick, the resistance is large, the amount of steam passing through is less, or even No. The distillation process of air on the fractionator tray depends on the mass transfer and heat transfer between the rising steam and the liquid on the tray. The more the gas and liquid contact on the tray, the more perfect the distillation process will be, and the more conducive to the separation of oxygen and nitrogen.Air separation plant.Plate fin heat exchanger belongs to inter wall heat exchanger. It is a compact and efficient heat exchanger with all aluminum structure. Each channel is composed of partition, fin, guide fin and seal. Fins and guide fins are placed between two adjacent partitions, and both sides are sealed with seals to form a sandwich, which is called "channel".When the processing air volume and compressed temperature of the air compressor are fixed, if the processing air is compressed to 1MPa (gauge pressure) and 2MPa (gauge pressure) respectively, the absolute pressure of the former is almost half that of the latter, that is, the volume is almost twice as large as that of the latter, the mass of the moisture content will also be nearly doubled.
Air separation plant.In practical operation, the temperature balance between two groups is mainly adjusted according to the temperature difference in the middle of two groups of cold accumulators or two groups of switching heat exchangers. The middle temperature difference between groups is generally controlled within 10 ℃. In addition, the actual control in the operation is often the temperature of the air at the outlet of the circulation or the middle outlet, no matter whether it is the actual middle temperature or not.Air separation plant.The air separation column has the following requirements for the foundation: in order to ensure the level of the distillation tray, the uneven settlement of the foundation should be avoided as far as possible; effective cold insulation, cooling dispersion, waterproof and drainage measures should be taken to prevent frost heaving and foundation rupture; the site with high terrain, low groundwater level, good surface drainage and low frost heaving of the foundation should be selected as far as possible; inflammable and explosive materials are strictly prohibited Material.
After cold blowing, the temperature decreases and a flat head peak appears. The longer the curve distance of the flat head peak is, the more water enters into the molecular sieve. In order to prevent the water inflow accident of Molecular Sieve Purifier, attention should be paid to the operation: the air cooling tower should be operated according to the operating procedures, first the gas is injected, and then the water is injected after the pressure rises and stabilizes; the gas volume should not be increased or reduced suddenly;If the refrigerating capacity is too much, for example, when the working pressure of the medium pressure device is too high, the moisture content of the air entering the lower tower will increase, the heat load of the main cooler will decrease, the evaporation capacity of liquid oxygen will decrease, and the liquid oxygen level will rise. Therefore, whether the cooling capacity of the device is balanced or not is first reflected in the change of the main cooling liquid level.
