The core of air separation equipment is to separate air into pure gases such as oxygen and nitrogen through deep freezing. Dust, water, carbon dioxide, hydrocarbons and other impurities in the air, if not removed in advance, will seriously affect the safe and stable operation of the equipment, and even cause equipment damage and production accidents. This is the core reason that impurities must be removed first.
Dust will wear precision parts such as impeller and bearing of air compressor and turbine expander, reduce equipment operation efficiency and service life, and may block the filter, resulting in insufficient air intake. Under the low temperature environment (up to - 196 ℃) of air separation equipment, water and carbon dioxide will quickly condense into ice and dry ice, block the channel of heat exchanger, throttle valve and sieve plate of rectifying column, cause sudden drop of heat exchange efficiency and system pressure imbalance, and force the equipment to shut down for overhaul.
Hydrocarbons (such as methane and acetylene) have low boiling points and are difficult to be separated in the rectification process. They will accumulate in the column. When reaching a certain concentration, they are easy to explode and have great potential safety hazards. In addition, impurities will pollute the separated oxygen and nitrogen products, reduce the product purity, and cannot meet the demand of industrial production (such as metallurgy and chemical industry) for high-purity gas. To sum up, removing impurities is the premise for safe, continuous and efficient operation of air separation equipment and the key to ensure product quality.
