Membrane air separation nitrogen production purity high gas production fast

Membrane air separation nitrogen is based on air. Under certain pressure conditions, gases with different properties such as oxygen and nitrogen have different permeation rates in the membrane to separate oxygen and nitrogen. Compared with other nitrogen-making equipment, it has the advantages of simpler structure, smaller volume, no switching valve, less maintenance, faster gas production (≤3 minutes), convenient capacity increase, etc. It is especially suitable for nitrogen purity ≤ 98% of medium and small nitrogen users have a good price ratio. When the purity of nitrogen is above 98%, it is more than 15% higher than the nitrogen generator of the same specification.

Cryogenic air separation nitrogen is a traditional nitrogen production method that has been in recent decades. It uses air as a raw material, is compressed, purified, and then uses heat exchange to liquefy air into liquid air. The liquid air is mainly a mixture of liquid oxygen and liquid nitrogen, which has different boiling points of liquid oxygen and liquid nitrogen (the boiling point of the former is -183 ° C at 1 atm, and the latter is -196 ° C), and the distillation through liquid air Separate them to obtain nitrogen. The cryogenic air separation nitrogen production equipment is complex, covers a large area, has a high capital cost, has a large investment in equipment, high operating cost, slow gas production (12~24h), high installation requirements and long cycle. Comprehensive equipment, installation and infrastructure factors, equipment below 3500Nm3/h, the investment scale of PSA equipment of the same specification is 20%~50% lower than that of cryogenic air separation unit. The cryogenic air separation nitrogen plant is suitable for large-scale industrial nitrogen production, while the medium and small scale nitrogen production is uneconomical.

Molecular sieve air separation nitrogen is a method in which air is used as a raw material, carbon molecular sieve is used as an adsorbent, and the principle of pressure swing adsorption is utilized to selectively separate nitrogen and oxygen by carbon molecular sieve for selective adsorption of oxygen and nitrogen, which is generally called PSA nitrogen production. This method is a new nitrogen-producing technology that was rapidly developed in the 1970s. Compared with the traditional nitrogen production method, it has simple process flow, high degree of automation, fast gas production, low energy consumption, product purity can be adjusted according to user needs in a wide range, convenient operation and maintenance, low operating cost, and equipment adaptation. It has strong characteristics, so it is competitive in nitrogen production equipment below 1000Nm3/h. It is more and more popular among small and medium-sized nitrogen users, and has become the preferred method for medium and small nitrogen users.