1. Determine the flow rate.

The first thing to know is that in general, the volume of the bottled nitrogen standard bottle we generally use is about 40L, the amount of nitrogen and oxygen contained in it is 6Nm3, and often the practical use of users is only 4.5-5Nm3, the rest can not be played out, because the gas supply manufacturer if the user will use up the gas, it will wash the bottle each time, and there is a certain connection with the pressure. Therefore, you must first know how many cylinders of gas are used in a day, and then how many hours these cylinders are used up. If you use 10 bottles of gas, it takes 10 hours to use up, then your hourly consumption is about 1 bottle, and the practical consumption of a bottle is about 5 quantities. Therefore, the flow rate should be selected 5Nm3/h.



2, determine the purity.

In general, there will be purity on the cylinder gas, this just need to look at yourself. If there is no concept, then you can consult the peer, design institute or nitrogen machine manufacturer to consult the detailed purity, which is related to the detailed use of nitrogen.



3, select the model.

At present, several nitrogen production methods have their own advantages, but PSA has the highest market share, followed by air separation equipment, and then VPSA nitrogen production, which is determined according to the detailed dosage and purity. If the amount is large and the purity is high (more than 99.99%), for example, more than 1000 cubic meters, you can choose cryogenic. If it is smaller than this, the purity is low (more than 90%), it is recommended to select PSA pressure swing adsorption nitrogen maker, if the initial degree is low and the flow rate is large, VPSA vacuum analysis can be selected, but the membrane separation is basically unnecessary on the market.