Air separation maintenance

There are four kinds of commonly used thermometers in air separation plant: industrial internal standard glass thermometer, thermocouple thermometer, thermal resistance thermometer and pressure gauge thermometer. According to the principle of temperature measurement, the range of temperature measurement and whether it can be transmitted remotely, four kinds of thermometers are used in different temperature measuring occasions of air separation plant. Industrial internal standard glass thermometer is used in small air separation plant to measure the temperature of all levels of compressor gas and cooling water locally, and it is also used for temperature measurement during heating and thawing; thermocouple thermometer is used for purifier; thermal resistance thermometer is used for low temperature measurement inside cold insulation box; pressure gauge thermometer is used for measuring lubricating oil temperature.

In the fractionating column, the separation of oxygen and nitrogen is realized through the process of two-stage distillation in the upper and lower columns. The distillation process must have ascending air and downflow liquid, and the main function of the condensing evaporator is to exchange heat between the liquid oxygen returned from the bottom of the upper column and the nitrogen rising from the top of the lower column. Condensing evaporator is an indispensable heat exchange equipment in air separation distillation system. In a sense, condensing evaporator is the link between upper column and lower column. The condensing evaporator is also called "main cooling". In the condensing evaporator, the liquid oxygen returned from the upper column absorbs heat and evaporates the gas oxygen; the rising nitrogen in the lower column is condensed into liquid nitrogen due to heat release. A part of the gas oxygen is sent out of the column as the product, and the rest is sent to the upper colu