Pressure maintaining of cold box of air separation equipment is the key link to ensure long-term stable operation of equipment. The core purpose is to prevent deformation of cold box, moisture of insulation layer, reduce cold loss and ensure efficient and safe operation of air separation system.
The air separation cold box is the core protection structure of the low-temperature equipment, filled with efficient insulation materials such as pearlite, providing thermal insulation guarantee for the low-temperature operation of the equipment. However, during the operation of the equipment, two hidden dangers are easy to occur, which need to be avoided through the pressure maintaining operation.
First of all, when the equipment is operating at low temperature, the internal gas and insulation materials will shrink due to low temperature. If the cold box is sealed, negative pressure will be formed inside. Long-term negative pressure will make the shell of the cold box bear the external atmospheric pressure, thus causing deformation and damage of the cold box, affecting the tightness and service life of the equipment.
Secondly, if the cold box is not well sealed, the moisture in the outside air will invade the inside, making the insulation materials such as pearlite damp. The insulation performance of the insulation layer greatly decreases after being affected with damp, which will lead to a sharp increase of cold loss. It not only improves the energy consumption, but also may block the pipeline due to the freezing of water, affecting the normal operation of the air separation system.
