In the complex and precise process of air separation equipment, the application of activated alumina is by no means optional. As the first solid line of defense for air purification, it ensures the long-term, stable, and efficient operation of the entire air separation system through its excellent deep drying capabilities and protective function.
Activated alumina is mainly installed in the pre-cooling system and molecular sieve purification system of air separation equipment. Its functions are specifically reflected in the following aspects:
1. Deep adsorption and drying to remove moisture
This is the core function of activated alumina. After compressed air is cooled, although most of the water vapor is separated, it still contains a large amount of saturated water vapor. When air enters the adsorber containing activated alumina, its huge specific surface area and microporous structure lock in the moisture through physical adsorption, achieving deep drying of the air. Lowering the dew point of the air to -40℃ or even lower is standard practice in the industry.
2. Synergistic Removal of Carbon Dioxide
While molecular sieves are the primary adsorbents of CO₂, activated alumina can also adsorb some CO₂. In molecular sieve purification systems, activated alumina is often combined with molecular sieves to form a composite adsorption bed. The activated alumina, located in the upper layer, adsorbs most of the moisture first, protecting the molecular sieve below. This allows the molecular sieve to more specifically adsorb CO₂ and residual trace amounts of moisture, thereby extending the lifespan of the molecular sieve and improving overall purification efficiency.
3. Protecting Core Equipment and Ensuring System Stability
Activated alumina, through deep air drying, directly protects downstream core equipment:
Main Heat Exchanger: Prevents moisture and CO₂ from freezing and clogging narrow flow channels, ensuring heat exchange efficiency.
Expander: Prevents moisture from freezing on the high-speed rotating impeller, causing equipment damage and downtime.
Distillation Column: Ensures stable operating conditions within the column, producing high-purity product gases.
In a typical process, air first undergoes coarse filtration and deep drying through an activated alumina layer, then undergoes fine filtration through a molecular sieve layer to remove CO₂. This division of labor leverages the advantages of each component while saving overall operating costs.
The selection of activated alumina in air separation equipment is primarily based on the following advantages:
Excellent deep drying effect:Significant dew point reduction and stable, reliable drying performance.
Economical and efficient:Compared to using molecular sieves exclusively, the composite bed design significantly reduces adsorbent purchase costs.
High strength and long lifespan: Wear-resistant and crush-resistant, maintaining long-term performance even under harsh process conditions.
Excellent synergistic effect:Perfectly complements molecular sieves, achieving a purification effect greater than the sum of its parts ("1+1>2").
Zibo Xiangrun's activated alumina, with its optimized pore structure and superior crush resistance, can precisely match the operating conditions of your air separation equipment, achieving deep drying and effectively protecting downstream molecular sieves. This significantly extends the overall lifespan of the adsorbent and reduces your overall operating costs. If you have any questions or needs regarding activated alumina, please contact Zibo Xiangrun Environmental Engineering Co., Ltd. – a professional alumina manufacturer.
