Qualification of air separation unit

Internal compression air separation process is a process form in which liquid products are pressurized by liquid pump in the cold box, and then sent out of the cold box after reheating by high-pressure heat exchanger. The working pressure of internal compression process generally exceeds the critical point of oxygen and nitrogen. Heat transfer of liquid in supercritical state is a major feature of internal compression process. In the distillation process, due to the difference of product types and acquisition methods, there is a big difference between the material import and export of internal equipment and external compression process. In the internal compressed air separation process, the pressure of oxygen is not limited, the maximum output of nitrogen can reach 2.8 times of that of oxygen, and the extraction rate of argon can reach about 85%. The internal compression air separation process is generally composed of internal compression system, air precooling system, molecular sie

The most common failure of the liquid oxygen pump is the leakage of the seal. For the structure of mechanical seal, the key is the bad contact of the sealing surface of the dynamic and static ring of the friction pair. It is related to the grinding quality of sealing surface, the assembling quality of pump shaft and bellows, and the material of friction pair. For the labyrinth type seal structure, it is related to the adjustment of the seal clearance and the pressure of the seal gas. Other faults and solutions are as follows: 1) the pump can't start: the current is blocked. The circuit should be rechecked to switch on the current; the rotor gets stuck or the gap is too small. The pump should be removed for inspection and the clearance should be adjusted. 2) no drainage after starting: the steering of the pump is opposite. Check the motor steering, change the power wiring; the pump is not fully precooled, gas is generated. The pump should be stopped and fully precooled again; the inl...