Summary of molecular sieve purification system problems

1. Functions and advantages

1. Function It absorbs the moisture, acetylene, carbon dioxide and some hydrocarbons in the raw material air to ensure the normal and safe operation of air separation. Its adsorption and absorption are water, acetylene, carbon dioxide, and other hydrocarbons in order. (Standard export carbon dioxide index for molecular sieve work)

2. Advantages The molecular sieve Jinghua air process has many advantages such as large product extraction volume, simple operation, long operation cycle, safe and reliable use, etc.

2. Structure

   The molecular sieve adsorber adopts a horizontal double-bed structure, that is, a certain amount of activated alumina is installed at the inlet of the purifier, and then a layer of 13X molecular sieve is installed on it. The molecular sieve purifier with double-layer bed structure has the characteristics of enhanced adsorption effect, extended use time, reduced regeneration energy consumption, and extended service life compared to a single-layer bed purifier filled with molecular sieve only. The activated alumina of the double-layer bed can reduce the pulverization of the molecular sieve and prolong the life of the molecular sieve. The activated alumina is located at the inlet of the processing air and can also distribute the air evenly; the aluminum glue is also resistant to acid and can protect the molecular sieve .

3. Ability of molecular sieve to adsorb impurities

The molecular sieve adsorber adsorbs moisture and carbon dioxide at room temperature, and can adsorb acetylene and other hydrocarbons. According to the information provided by Linde, the adsorption efficiency formula and experimental data of molecular sieve to remove acetylene and other hydrocarbons are as follows:

ηx=(1-yci/yji)×100%

In the formula ηx-the average adsorption efficiency of a certain hydrocarbon CnHm;

yci--the concentration of a certain hydrocarbon CnHm at the outlet of the adsorber;

Yji--the concentration of a certain hydrocarbon CnHm into the adsorber.

Among them, the adsorption efficiency of CH4, C2H6 is almost zero; C3H8 is 89%; C2H4 is 97%; C3H6, C2H2 and C4H10 are almost 100%. It can be seen from the above data that molecular sieve purification can remove acetylene, propylene, etc., but it is ineffective for methane and ethane. (Why do you add an analyzer for detecting methane, total hydrocarbon, and total carbon at the air inlet)