Liquefied air separation FAQ

The liquid in the lower tower mainly comes from the liquid flowing from the first tower plate at the bottom. The liquid flowing down from the top Tower plate contacts with the air entering the tower on the first tower plate, part of the liquid evaporates, and the oxygen concentration in the liquid increases before flowing into the liquid kettle. However, its oxygen concentration is limited by the oxygen concentration (20.9% O2) of the air entering the tower, which is always lower than its equilibrium concentration. For example, when the pressure of the tower is 0.55 MPA, the oxygen concentration in the liquid which is balanced with the vapor containing 20.9% oxygen is 40.8%, while the actual oxygen concentration in the air should be lower than this value. Equilibrium concentration is related to pressure. With the increase of pressure, the equilibrium concentration decreases, and the oxygen concentration in liquid air also decreases. For example, when the pressure is 0.6MPa, the equi...

In the whole low-pressure air separation process, some are equipped with a liquid purifier, and some are equipped with two or even three liquidators, which make part of the air liquefied by the cold energy of polluted nitrogen, pure nitrogen or pure oxygen respectively. Some even combine the liquid purifier with liquid air and liquid nitrogen supercooler. The air flowing through the liquid purifier comes from the washing air of the lower tower or the low temperature air at the cold end of the switching heat exchanger. The function of the liquid purifier is related to the air separation process and start-up mode. Generally, it has the following functions: 1) in the stage of starting the hydrops, the liquidator plays the role of liquefied air and accumulating liquid. In some processes, the liquid purifier is not set up separately. For example, the 6500m 3/h air separation plant of the French liquefied air company makes the liquid air cooler, the sewage nitrogen cooler and the expansio...

The subcooler of the distillation tower of an air separation plant

Liquid gasification filling system consists of liquid storage tank, liquid pump and air purifier. In order to ensure the normal operation of the liquid pump, besides the reliability of the structure of the pump itself, the piping technology is also very critical. Improper piping, if it is light, it will cause "cavitation phenomenon" of the liquid pump, and the decrease of flow rate will lead to large mechanical loss of the pump; if it is serious, the filling pressure cannot be improved due to the serious gasification of the liquid in the pipe, the pump cannot work normally. Therefore, the following problems should be paid attention to when piping: 1) the base of the storage tank should be over 1m higher than the center of the liquid oxygen pump to ensure that the inlet of the pump has a higher static pressure (higher than the saturation pressure corresponding to the temperature ); 2) shorten the length of the pipeline from the storage tank to the pump inlet as much as possible to re...

What are the types of distillation tower plates in air separation equipment and what are their applications

Purification process of molecular sieve adsorbers in air separation equipment

The air separation equipment generally uses rivers, lakes or underground water as cooling water. This kind of water usually contains suspended solids (sediment and other dirt) and calcium, magnesium and other heavy carbonate [-Ca (hissu2) 2 and Mg (hissu2) 2], which is called hard water. When there are many suspended substances, it is easy to block the passage, filter screen, Valve and so on of the cooler. When the water temperature rises, calcium carbonate, magnesium and other heavy carbonate are easy to generate calcium carbonate and magnesium carbonate precipitates, which are commonly called scale. Generally, when the water temperature is above 45℃, scale will begin to form, and the higher the water temperature is, the easier it is to scale. The scale attaches to the tube wall of the cooler, the stuffing of nitrogen-water precooler, nozzle or sieve hole, which not only affects the heat transfer and reduces the cooling effect, but also hinders the circulation of cooling water or a...

What should be paid attention to when filling cold insulation materials in air separation equipment

Liquid oxygen, liquid nitrogen and liquid argon are widely used in liquid gasification stations to supply gas directly or fill bottles. In order to ensure the safe operation of the aerator, safety control points should be set up and the following matters should be paid attention: 1) set the low temperature control interlock point of the low temperature liquid outlet air purifier. Control the gas outlet temperature to 5 ~ 30℃. When the outlet temperature is lower than 0℃, the liquid pump will be cut off automatically and the liquid will be stopped from entering the air purifier. The air purifier without liquid pump will give out sound and light alarm; 2) set air purifier water temperature control interlock point. Control the water temperature at 40 ~ 60℃. When the water temperature is lower than 30℃, the liquid pump will be cut off automatically, and the liquid will stop entering the air purifier; 3) set the pressure control interlocking point of gasification gas outlet, and control ...

How does a plate-fin heat exchanger achieve heat transfer between several streams of fluid

Requirements for adsorbent and adsorbent in air separation equipment

Plate spacing of sieve tray tower of air separation plant