Nitrogen is an inert gas, which is often used in high temperature treatment of various materials or parts of the protective atmosphere. Therefore, impurities (oxygen and water vapor) in nitrogen should be removed to a low level.

一般來(lái)說(shuō)，由制氮機制取的氮氣中含氧量小于0.5%時(shí)，宜采用脫氧劑直接除氧，含氧量為0.5-3%時(shí)，宜采用催化劑加氫除氧，含氧量大于3%時(shí)可采用分級催化除氧。

Generally speaking, when the oxygen content in nitrogen produced by nitrogen generator is less than 0.5%, Deoxidizer should be used for direct deoxidation; when the oxygen content is 0.5-3%, catalyst hydrogenation should be used for deoxidation; when the oxygen content is more than 3%, staged catalytic deoxidation can be used.

因為氮氣中含氧量過(guò)高，按化學(xué)計量所需的氫氣量大，一次全部加入時(shí)，可能有爆炸的危險；且反應中放出的熱量較大，易燒壞催化劑。因此，必須嚴格控制加氫量進(jìn)行分級除氧。原料氮氣中含氧量過(guò)高時(shí)，亦可用部分純氮稀釋原料氣，使混合氣體中含氧量小于3%再進(jìn)行加氫催化除氧。

Because the oxygen content in nitrogen is too high, the amount of hydrogen required by stoichiometry is large, and there may be a risk of explosion when all the nitrogen is added at one time; And the heat released in the reaction is large, which is easy to burn the catalyst. Therefore, it is necessary to strictly control the amount of hydrogenation for staged deaeration. When the oxygen content in the feed nitrogen is too high, the feed gas can also be diluted with some pure nitrogen to make the oxygen content in the mixed gas less than 3%, and then the hydrogen catalytic deoxidation can be carried out.

采用脫氧劑清除雜質(zhì)氧的典型工藝流程：氮氣經(jīng)催化除氧器（除去氧）、水冷卻器和吸附干燥器（除去水汽）、氣體過(guò)濾器（除去塵埃顆粒）后，即得純氮產(chǎn)品。

The typical process flow of removing impurity oxygen by deoxidizer is: nitrogen passes through catalytic deaerator, water cooler, adsorption dryer and gas filter to get pure nitrogen product.

采用加氫催化除氧的典型工藝流程：首先在氮氣中加適量氫氣（添加量為氮氣中含氧量的二倍以上），然后通過(guò)催化除氧器（除去氧）、水冷卻器和吸附于燥器（除去水汽）、氣體過(guò)濾器（除去塵埃粒）后，即得純氮產(chǎn)品。

The typical process flow of hydrocatalytic deoxidization is adopted: firstly, appropriate amount of hydrogen is added into nitrogen (the addition amount is more than twice of the oxygen content in nitrogen), and then pure nitrogen product is obtained through catalytic deoxidizer (deoxidization), water cooler and adsorption in dryer (moisture removal) and gas filter (dust removal).

當氮氣中含氧量較大（大于3%），可采用分級加氫催化除氧工藝，氮氣在進(jìn)入催化除氧器前，需要嚴格控制加氫量，通過(guò)催化除氧器1（一次除氧），再加入少量氫氣進(jìn)入催化除氧器2進(jìn)行二次除氧。

When the oxygen content in nitrogen is large (more than 3%), the staged hydrogenation catalytic deoxidation process can be used. Before the nitrogen enters the catalytic deoxidizer, the amount of hydrogenation should be strictly controlled. The catalytic deoxidizer 1 (primary deoxidization) and a small amount of hydrogen should be added to the catalytic deoxidizer 2 for secondary deoxidization.

如果原料氮氣中含氧較高，對純氮又要求不許有過(guò)量氫氣存在。此時(shí)，氮氣純化裝置采用先加氫催化除氧，再用活性氧化銅等除氫的方法純化氮氣，其典型的工藝流程為：在原料氮氣中根據氧的含量，添加稍為過(guò)量的氫（按化學(xué)計量）后通過(guò)催化除氧器除氧，再通過(guò)電加熱器和氧化反應除去氮氣中的過(guò)量氫。常用的脫氫劑除活性氧化銅外，也可用銀分子篩等。

If the oxygen content in the nitrogen is high, the pure nitrogen should not have excessive hydrogen. At this time, the nitrogen purification unit adopts the method of hydrogenation catalytic deoxidation first, and then active copper oxide to purify nitrogen. The typical process flow is as follows: according to the oxygen content in the raw nitrogen, add a little excess hydrogen (according to stoichiometry), deoxidize it through the catalytic deaerator, and then remove the excess hydrogen in the nitrogen through electric heater and oxidation reaction. In addition to active copper oxide, silver molecular sieve can also be used as dehydrogenation agent.