When ordinary nitrogen gas containing oxygen less than 0.1 % flows into the oxygen remover, the oxygen reacts sufficiently with the carbon in the carbon-carrying deoxidant at high temperature to form carbon dioxide (C + O2 = CO2), and the content of residual oxygen may reach below 10 ppm.

After removing oxygen, the nitrogen gas flows through a cooler to decrease temperature and then into the dryers in which carbon dioxide and residual moisture are deeply removed. The dryers are two adsorbers packed with molecular sieve, one of them is adsorbing to dry the nitrogen gas, and the other, having adsorbed in saturation, is regenerated at high temperature. The normal-pressure dew point of the nitrogen gas can finally reach less than -60 ℃.

The gas purified is conveyed through a pure nitrogen tank and then to nitrogen-using spots.

Ordinary nitrogen gas flows into the oxygen remover packed with the carbon-carrying deoxidant. The oxygen reacts with the carbon at 300 ~ 350 ℃ to form carbon dioxide, and consequently to make the oxygen vanish. There are two oxygen removers in the system, one as a standby, and the other being working for almost one month. Carbon dioxide and moisture in the gas out of the oxygen remover are adsorbed in a molecular sieve dryer. The dryer works at normal temperature and is regenerated at high temperature. After drying, the nitrogen gas contains oxygen and carbon dioxide less than 1 ppm, and moisture less than 10 ppm. Warnings of low temperature, low pressure and nitrogen purity are organized for the oxygen removers in order to effectively monitor the system.

The scope of application

The system is applicable to the cases of strictly restricting the content of oxygen and hydrogen.

Advantages of purification with carbon-removed oxygen:

    ① High reliability: the system is operate at temperature of 250 ~ 350 ℃, at which the operation is not affected by the other equipment. High-purity nitrogen is steadily supplied automatically; 

    ② High industrial safety: the reaction of oxygen and deoxidant forms inactive gas which does not endanger industrial safety at low pressure and not very high temperature; 

    ③ High-quality nitrogen: the impurities, inactive gas from the reaction of oxygen and deoxidant, and moisture etc., can be treated reasonably, which ensures the quality of product nitrogen.

Disadvantages of purification with carbon-removed oxygen:

    ① Manufacturing costs are higher than the purification system with hydrogen; 

    ② Expenditure of the material consumption is more than the purification system with hydrogen; 

    ③ The reaction temperature and heating power are higher than the purification system with hydrogen.