For the Oxygen concentrator with separate upper and lower towers, the liquid oxygen at the bottom of the upper tower is pumped to the main cooling at the top of the lower tower by the liquid oxygen pump. The forced valve malfunctioned, causing a sudden and significant decrease in the inlet air pressure, as well as a decrease in the upper tower pressure and main cooling pressure. For a liquid oxygen pump, the imported liquid oxygen should be in a supercooled state, because if some of the liquid oxygen is vaporized in the pump, the pump's capacity will decrease and it cannot smoothly deliver liquid oxygen to the main cooling system. When the pressure of the upper tower drops too much, the temperature of the liquid oxygen at the inlet of the liquid oxygen pump will exceed the saturation temperature corresponding to this pressure, causing some liquid oxygen to gasify and produce "entrainment" phenomenon, making it impossible to deliver liquid oxygen, causing the liquid level at the bottom of the upper tower to rise.
In addition, when the air is bypassed and the pressure on the lower tower surface suddenly drops to 0.2MPa, the temperature difference between the main cooling system decreases, the thermal load of the main cooling system decreases significantly, and the liquid oxygen cannot evaporate, which may even cause liquid leakage on the tower plate and cause a sudden increase in the liquid level. At this point, if the oxygen production is not reduced in time, the steam rising from the upper tower will inevitably decrease, the liquid to gas ratio in the distillation section will increase, and the purity of liquid oxygen will deteriorate. If the tray leaks, the purity will be destroyed faster.
Therefore, when the forced valve malfunctions, it will cause a series of changes inside the tower, causing damage to the working conditions and posing great harm, which must be given sufficient attention.
During the manufacturing process of the KDN-1500/100Y high-purity nitrogen equipment provided by DEAR Air Separation for Kangbo New Materials Co., Ltd., multiple utility model patent certificates were obtained for the supporting monomer equipment of the project. Among them, Deer Air Separation independently developed a condensation evaporator for distillation air, which achieved the effects of safety, energy conservation, and easy operation. The application of a distillation air sink easily adjusts the length of the sink device, with good limit effect and wide application range.
