Polyphosphoric acid as the method of drying air in chemical industry

Polyphosphoric acid as the method of drying air in chemical industry

Polyphosphoric acid as the method of drying air in chemical industry. Some engineering magzines reported polyphosphoric acid could be used to dry air in chemical process with better cost-efficiency. 

Howerver, we either agree or disagree what this technology mentioned, just provide this information as reference for related one.  The reader should be responsible of if or how to use this information. 


The key points as below: 

The gas drying process includes cooling and drying, liquid absorption and drying, solid absorption and drying, membrane dehumidification, thermoelectric condensation, and rotation.

Among them, cooling and drying, liquid absorption, solid absorption, and rotation are several drying methods commonly used in the industry.

The liquid absorption drying method is the most widely used because it has the advantages of large processing gas volume, low moisture content of the gas after drying, low energy consumption, and reliable operation.

At present, the most widely used desiccant for liquid absorption drying method is sulfuric acid, but there are three problems in enterprises that do not have sulfuric acid production:

There are safety issues in the transportation of sulfuric acid raw materials,

After drying, the dilute sulfuric acid has problems in transportation and sales again.

Corrosion and safety issues in the drying process of sulfuric acid.

The use of polyphosphoric acid to dry air is a new type of drying method. The method uses industrial polyphosphoric acid as a liquid desiccant.

The partial pressure of water vapor on the surface of polyphosphoric acid is much lower than that in humid air. Under the action of the pressure gradient, the moisture in the air is absorbed into the polyphosphoric acid, thereby removing the moisture in the air.

Compared with the existing industrial common cooling dehumidification, solid and liquid adsorption dehumidification, rotary dehumidification, thermoelectric condensation dehumidification, this method is especially suitable for chemical enterprises that adopt the solid adsorption + freeze-drying process to replace the air drying process.

Utilizing the strong water absorption of polyphosphoric acid and using polyphosphoric acid as a desiccant can not only reduce the manufacturing and maintenance costs of drying equipment, but also improve the safety of industrial production, dehydration efficiency, low energy consumption, and large processing gas. It is safe and reliable, small footprint, no by-products, low equipment operation and maintenance costs, and has significant economic benefits.