If the outlet temperature of the purifier rises suddenly in the process of using, it means that the air has brought the water in the air cooling tower into the adsorber and should be treated urgently. At the beginning of switching, there is a large temperature difference between the inlet and outlet, even as high as 20 ℃. This is due to the fact that the process of the adsorber switching to charging is a process of pressure increasing, and the adsorption capacity of the molecular sieve increases. Carbon dioxide precipitation stage. In this stage, only the switching heat exchanger is cryogenic, so that the carbon dioxide is frozen in the heat exchanger and carried out by the low-pressure backflow gas until the cold end temperature reaches - 170 ℃; The fourth stage is to use the purified low-temperature gas to further cool other equipment until liquid accumulates in the tower, and then further adjust the distillation condition.
For the same substance, higher saturation pressure corresponds to higher saturation temperature. Increasing the pressure can increase the liquefaction temperature and make the gas easy to liquefy. That is, at a certain temperature, it can be liquefied by increasing the pressure. However, for every substance, when the temperature exceeds a certain value, no matter how high the pressure is, it is impossible to liquefy it. This temperature is called critical temperature. There are three types of fins commonly used by air separation plant manufacturers: straight fin, serrated fin and multi hole fin. Straight fins are rectangular fins with smooth walls. The main function of this kind of fin is to expand the heat transfer area, but it has little effect on promoting fluid disturbance. Therefore, its heat transfer performance is slightly worse, but its flow resistance is small. It is suitable for the case of large heat transfer temperature difference between high temperature fluid and low temperature fluid, and can also be used for the case of large heat transfer coefficient when the fluid has phase change.
The oxygen flow rate in the oxygen pipeline of the air separation plant manufacturer shall be less than 6m / s when the pressure is greater than 10MPa according to the code for design of oxygen station (GB 50030-91); When the pressure is between 3Mpa and 10MPa, the flow rate should not be greater than 10m / s; When the pressure is 0.1MPa to 3Mpa or below, it shall not be greater than 15m / s; For the irreversible adiabatic process, the entropy increases. In other words, the physical quantity entropy can express the direction of the process. The spontaneous process in nature always goes in the direction of the increase of the total entropy, and the total entropy of the ideal reversible process remains unchanged. For the above two irreversible processes, the entropy of the final state must be greater than that of the initial state.
If the air separation plant manufacturer reduces the pressure, the corresponding saturation temperature will also decrease. Some saturated liquid will gasify and absorb heat, becoming a mixture of saturated liquid and saturated steam under low pressure, and the temperature is equal to the saturation temperature under the pressure. The throttling of liquid air and liquid nitrogen is in this case. All kinds of liquid pipelines or cold pipes should be close to the internal cold container as far as possible, while the gas pipeline should be arranged outside the liquid pipeline; The distance between the gas pipeline and the wall of the cold insulation box (that is, the thickness of the insulation layer) should be in the following range: at - 50 ～ - 130 ℃, it should be greater than 200 ～ 400mm; At - 130 ～ - 196 ℃, it should be more than 300 ～ 600mm;
