Spray dryer

Drying is the process of removing moisture or other volatile substances from solids, sludges and suspensions. Various types of dryers are used for this process. Since heat can be transferred in several ways, there are five types of dryers – convection, diaphragm, radiant, dielectric and microwave and special. One of the types of convection dryers is the spray dryer and fluidized bed dryer produced by our company.

1) Spray dryer:
Spray drying is a method of dehydrating raw materials while atomizing the substance fed to the drying chamber. The process is carried out in a strictly set temperature regime. The final product is dehydrated dry material in several possible forms – dusty powders, microcapsules, granules – depending on the prepared initial mixture and process conditions. Raw materials subjected to spray drying are dispersions, emulsions, solutions, pastes, other non-Newtonian fluids, which may form the desired product under appropriate conditions.

Typical spray drying applications generate products such as:

• in the food industry: powdered milk, powdered whey, sports nutrition, flavouring additives, powdered eggs, etc.
• in biotechnology and pharmaceutical industry: yeasts, bacterial strains, powdered emulsions for further processing e.g. tabletting, encapsulation of temperature-sensitive ingredients etc.
• in the chemical industry: highly porous powders, silica, sol, etc.

2) Fluid bed dryer:
Fluid bed drying consists of feeding a stream of hot gas into the drying chamber, where bulk substances are located.A fluidised bed is formed – a dynamic suspension, where the solid particles in the gas stream move upwards from below. A fluidised bed is formed, i.e. a dynamic suspension, where the solid particles in the gas stream move from bottom to top. Fluidization is characterized by a developed interfacial surface and mixing of the fluid through the movement of solid particles, which intensifies the drying process. The fluidized bed dryer is a universal device for thermal drying, agglomeration, coating and microencapsulation processes.

Drying process:
A solid material subjected to the drying process in a hot air atmosphere with simultaneous fluidised movement gives up water evenly from its surface, causing the separation of the agglomerated material by collision of the particles.

Agglomeration process:
The solid material put into the fluidised state can be wetted by spraying nozzles with a binder, causing its agglomeration and thus increasing the diameter of the product to a target size.

Coating process:
To obtain an even protective coating, e.g. against product aging, glossy coating, others, by dosing the coating emulsion in the fluidised state and the set temperature regime, we obtain an even distribution of the coating material in each granule.

Micro-encapsulation:
Active components introduced into the coating solution are successfully dosed onto the granule core material, under appropriate process conditions we obtain equal concentration of active materials inside the granules.

It is worth adding that the efficiency of the dryer is best determined by the amount of evaporated water per unit of time. This allows for universal design of the device, without breaking the secret of the recipe. Spray dryers and fluidized bed dryers are used in many branches of industry, including food, pharmaceutical and biotechnological industries.

Do you have any doubts whether the dryer can handle your application? Check its capabilities. Contact us and rent it for testing! Our engineers will answer all your questions.

Download the survey

Below is a downloadable questionnaire to help you choose the right solution:

Customer survey – Spray dryer