Analysis of Losses in High-Purity Neon Production Technology. Part 2.* Processing of a Ne–He Mixture to Obtain Pure Products

Abstract

Inert gases are valuable products that are widely used in industry. Their processing scheme includes several enrichment, purification, and separation stages of a Ne–He mixture (NHM). Primary enrichment of the NHM occurs in air-separation plants. Secondary enrichment uses a reflux condenser at liquid N₂ temperature (~78 K). The impurity concentration at the reflux condenser outlet can be decreased by reducing the operating temperature. However, the specific energy consumption increases whereas the extraction coefficient is practically not affected if a vacuum pump is applied. A promising trend for reducing the cooling temperature is to use non-machine cold sources. The Ne extraction coefficient during rectification depends on the impurity (He) content in the waste gases. The main method for increasing the efficiency of Ne production installations is to use additional non-machine cooling of the rectification input stream. The adsorption installation for recycling Ne from He concentrate can be chilled using two coolants, i.e., Ne and liquid N₂. The research showed that the specific energy consumption of the separation is 5–7 times greater to reach Ne temperature (28 K) than liquid N₂ temperature (78 K).