Liquid air fractionation plant after a long period of operation, in the fractionation tower system of low temperature containers and pipelines may produce ice, dry ice, hydrocarbons and other deposits, resulting in a gradual increase in device resistance, increased energy consumption, affecting the purity and yield of the product. For this reason, whenever the unit runs after a cycle, the fractionator system should generally be fully warmed and thawed to remove these deposits.
Liquid air separation plant in the operation process if the heat exchanger and distillation tower resistance increases or turbine expander inlet pressure drops, the speed drops sharply, the fractionation should be warmed and thawed in advance, or the turbine expander for local heating. Liquid air fractionation plant heating gas source for the purification of molecular sieve purifier after the room temperature dry air, the principle of heating is from top to bottom, from inside to outside, as far as possible to achieve a slow and uniform temperature rise in all parts of the liquid air fractionation plant, to avoid the temperature rise too quickly, resulting in a large temperature difference, and then produce a large thermal stress, resulting in damage to equipment or pipelines. When heating up, all instrumentation and testing pipelines must also be heated up and blown out at the same time.
DEAR Air has instructions for the use and maintenance of all liquid air separation plants manufactured by DEAR Air. When heating, the relevant systems are shut down, all liquids are drained and all valves are closed. There are requirements for the volume and temperature of the heating gas, and attention is always paid to the size and pressure of each blow-off gas.