Simple & Cost effective Product Drying using Dehumidification
The problems related to product drying are typically :
- the Quality of drying
- the Speed of drying
Conventionally, products are dried through Hot Air Drying. However, most products which require drying are temperature sensitive. Moisture is present in the products as:
- Free moisture in form of surface moisture generated due to washing or mixing the product with water prior to drying
- Hygroscopic moisture which is held within the product
- Combination of both types
Drying Technology involves the removal of all moisture to the desired content. Surface moisture (and it is often assumed that it is the only type of moisture present) is conventionally removed by raising the product temperature by using hot air to vaporize the moisture. However, this can result in product spoilage as many products like cocoa, gelatine, coffee etc. are temperature sensitive and need to be dried at low temperatures.
If the relative humidity of surrounding air is lower, then the product will give up its hygroscopic moisture to the "drier air" to be in equilibrium with its surrounding. Velocity of the air over the product has little or no bearing on the drying speed.
Product drying applications are typically: Bulk (batch) drying: when the material is loaded into a compartment and the entire load is dried as a batch and continuous drying: when the wet material is continuously fed into a drying chamber and it leaves the chamber, dried to the desired moisture level.
Usually, the sudden change in drying rate (at the critical point) denotes where the initial drying via removal of free moisture ends, and hygroscopic drying takes over. In other words, the product has lost its free moisture, but is still hygroscopically saturated. However, the net effective drying surface and the hygroscopic properties cannot be determined in any other way.
Benefits of using Dehumidification for drying over other methods :
Desiccant Dehumidification is the simplest and most cost effective method to ensure drying without spoilage as the drying is based on the difference in vapour pressures of water in the product and the surrounding air. By physically removing moisture from air, through the process of physical adsorption, the evaporative potential of the air is maximized.
Application Areas: Drying Food, Drying Seed, Drying wood, Gelatine Drying, Yeast Drying, Powder Drying, Spices Drying, Grapes Drying, Fruit Drying.
Bry-Air Desiccant Dehumidifiers have been used effectively by many manufacturers / processors of dried products and are ideal solution to dry products as they ensure:
- better quality drying with more uniform drying
- faster drying rate without the risk of product spoilage
- reduction in space needs for drying,
- rationalized energy consumption versus higher throughput; and
- removal of the variable of weather as a factor in a drying operation