Silica Gel in Drying of Gases
While Silica Gel is mostly known for removing humidity from packed spaces, it has various other uses as well. One of the important uses of Silica Gel is in the successful removal of moisture molecules from gases and liquids. Both of these are very vulnerable to moisture and are greatly affected by it. Companies working in the gas and liquid field make wide use of Silica Gel sachets to keep humidity at bay. Utmost care should be taken that there are no traces of moisture in gases/liquids as it adversely affects their use and movement from one place to another.
All over the world, Silica Gel is the first choice to remove moisture from gas and liquid streams. This is due to two factors- 1) large surface area of the Silica Gel molecules and 2) high rate of absorption. These characteristics help Silica Gel desiccant absorb more humidity in lesser time from natural gas and various other industrial gases. Silica Gel desiccant is also widely used in the hydrocarbon recovery process and the mass dehydration of compressed air.
Blue & Orange Indicating Silica Gel in Gas Drying
Based on its ability to absorb moisture, Silica Gel is divided into different categories/grades. It can be classified into Indicating (changes colour) and Non-Indicating (no colour change). The Indicating Silica Gel, in turn, can be found in Blue, Orange, Pink colours. These change colour when they become completely saturated with moisture. Blue and Orange grades of Indicating Silica Gel are mainly used to remove moisture molecules present in air/gases. This is applicable for both the static as well as dynamic situations. The colour change in both Indicating Silica Gel types will let one know when the Silica Gel adsorbent becomes fully saturated and when it needs to be replaced.
Silica Gel Orange
Orange Indicating Silica Gel packets change into dark green and becomes colorless as well. In the first case, the Silica Gel packets change color from a very bright orange (a dry state) to a dark green ( nearing saturation). When the Orange Indicating Silica Gel packets turn completely green, then it is understood that it can no longer absorb any more moisture.
Silica Gel Orange is known to contain iron salts and changes colour from a deep orange (dry state) to a colorless state, when all the moisture has been already absorbed. Orange Indicating Silica Gel packets are available as granules and beads.
Silica Gel Blue
Blue Indicating Silica Gel Packets contain cobalt and is sometimes considered poisonous. The Blue Indicating Silica Gel desiccant changes color from blue to pink, going from a dry state to a fully saturated state. It is available in 2 or 3-6 mm granular forms.