A by-product of air separation from a helium preparation method
1. The principle of preparing helium by air separation.
The preparation of helium by air separation method is based on the different boiling points of various components in the air (nitrogen, oxygen, argon, helium, etc.), and they are separated by low-temperature condensation. Specifically, the air is compressed, purified, and then enters the air separation plant, and at low temperatures, the components in the air begin to condense into liquids, and then they are separated by the method of rectification. Of these, helium has the lowest boiling point and is therefore the first to be separated during the distillation process.
2. The process of preparing helium by air separation.
The process of preparing helium by air separation mainly includes the following steps:
1.Air compression and purification: The air is compressed through the compressor and sent to the air purification device to remove moisture, dust and other impurities.
2.Cooling and liquefaction: The purified air is cooled to a very low temperature, allowing the gas components to condense into a liquid.
3.Distillation separation: Multiple heating and condensation operations are carried out in the distillation column to gradually separate the gas components at different boiling points. In this process, helium is the first to be separated due to its lowest boiling point.
4.Extraction and purification: Crude helium is extracted from the distillation column and further purified to obtain high-purity helium.
3. Advantages and disadvantages of preparing helium by air separation.
1.Pros:
1) Wide range of raw materials: air is the most abundant gas in nature, so the raw materials for the preparation of helium by air separation method are very rich.
2) Low production cost: Due to the wide range of raw materials, and the relatively low cost of equipment investment and maintenance, the production cost of helium prepared by air separation method is low.
3) High product quality: High purity helium products can be obtained through distillation separation and purification treatment.
2.Cons:
1) High energy consumption: Since both low-temperature condensation and distillation separation require a large amount of energy, the energy consumption of helium preparation by air separation method is high.
2) Limited production capacity: Due to the limitation of equipment scale and process conditions, the production capacity of helium prepared by air separation method is relatively small, which is difficult to meet large-scale demand.