Membrane separation: the basic principle of nitrogen production by membrane separation is to use air as raw material, under a certain pressure, to separate oxygen and nitrogen by using different permeability rates of gases with different properties such as oxygen and nitrogen in hollow fiber membrane. Compared with the above two methods, membrane separation has the advantages of simpler structure, smaller volume, no switching valve, more convenient operation and maintenance management, faster gas production rate (≤ 3min), and convenient expansion and expansion.
However, the hollow fiber membrane has higher requirements for cleaning compressed air, and the filter element of the membrane is easy to be aged and corroded, which is often difficult to repair and needs to be replaced with a new membrane. At present, hollow fiber membrane needs to be imported from abroad, which is expensive. Nitrogen production by membrane separation is more suitable for small and medium-sized nitrogen users who require nitrogen purity ≤ 98%, and has the best function price ratio. However, when the purity of nitrogen is required to be higher than 98%, its price is about 30% higher than that of pressure swing adsorption device of the same specification. Foreign funded gas companies in China use it as a leasing site to produce nitrogen.
On 2018-08-08 11:45:46
