When the screen hole is partially blocked by scale and dirt, the air flow rate increases, and when the flow rate exceeds a certain value, the air will carry water; the water injection hole of circulating cooling water distributor is blocked. At this time, it is difficult for the cooling water to flow down, and the water accumulates on the upper tray, causing flooding and water carrying;DEAR Cryogenic air separation unit.The incomplete cooling loss of heat exchange is caused by the backflow low temperature gas can not be reheated to the temperature of the positive flow air entering the heat exchanger when it comes out of the hot end of the main heat exchanger. Therefore, the larger the temperature difference between the hot end of the reflux gas and the positive air heat exchanger, the less reheating, the more unused cooling capacity, and the greater the incomplete cooling loss of heat exchange. Therefore, Q2 is directly proportional to the temperature difference at the hot end.DEAR Cryogenic air separation unit.When the gas with higher pressure expands through the expander, the energy (enthalpy) of the gas itself is reduced and the temperature is significantly reduced because the gas drives the impeller to rotate and outputs work. It has the ability to take away heat, which is the energy recovered before expansion after heat absorption. Therefore, the difference of energy (enthalpy) before and after expansion of expander is the cooling capacity of expander.
The process of accumulating the necessary cryogenic liquid in the distillation column is actually a process of "storing the cold capacity". In this process, the balance relationship of cooling capacity is: total cooling capacity = total cooling loss + cooling capacity required by liquid accumulation.The acetylene content in liquid air and liquid oxygen needs to be analyzed every day, so the liquid air and liquid oxygen discharge valves have to be operated every day. It is easy to open the valve, but difficult to close it. Sometimes it can't be closed at all. This is mainly because there is water in the valve stuffing box.DEAR Cryogenic air separation unit.According to the working pressure, it can be divided into high pressure device with pressure of 10.0 ~ 20.0Mpa, medium pressure device with working pressure of 1.0 ~ 5.0mpa and full low pressure device with pressure of 0.5 ~ 0.6MPa. The classification method is artificial, there can be other classification methods.After the fractionator is in place, put through the vertical line, adjust the pad iron to make the verticality of fractionator less than 1 / 1000, and install the foot screw. There are two installation methods of foot screw: one is to use the bottom plate hole of fractionator, the other is to press the bottom plate with pressing plate. And grouting once.
DEAR Cryogenic air separation unit.In order to prevent deflecting flow, the resistance difference of plate element should be strictly required in design and manufacture. For example, Japan stipulates that the resistance difference of each unit group should be controlled within ± 4%, and the resistance difference of two switching channels should be within 1.5%.DEAR Cryogenic air separation unit.The increase of resistance is closely related to the temperature condition of the heat exchanger. If the middle temperature is well controlled, the resistance increases slowly; if it is not well controlled, the resistance increases quickly. When the resistance increases due to the residual ice and solid carbon dioxide, measures should be taken to shorten the switching time, increase the ring flow or reduce the temperature difference at the cold end.DEAR Cryogenic air separation unit.After the excess hydrogen reaches 1% ～ 2% for about 1H, prepare to put the oxygen analyzer into operation (before analyzing the process argon, manually analyze whether the oxygen content in the process argon is less than 10-5, so as to prevent the micro oxygen analyzer from being damaged). When the oxygen content in process argon is less than 10-6, the refined argon tower can be put into operation.
