Spray Drying
Fine-grained powders from liquids containing solids.
Drying and shaping in one step.
A well-known solution for converting liquid substances into a solid product form.
The process of spray drying enables the recovery of fine-grained powders directly from liquids. The raw material to be dried is continuously sprayed into a hot gas stream. In a very short time – from fractions of a second to a few seconds – the liquid substance is dried to a fine powder.
Spray drying processes can be based on fluid bed technology and spouted bed technology as well as powder synthesis.
Powder production by means of spray drying has various applications in diverse industries, as the product properties can be varied in many ways by means of process engineering parameters and configurations. The powders produced in this way have a fine, open and porous structure. They often act as starting materials for subsequent spray agglomeration in the fluid bed or spouted bed. The powders can thus be optimized. Powder properties such as flowability, undersink behavior or dust tendency are improved.
Depending on the atomization principle and the solids content of the liquid, primary particles between 5 and 200 µm are formed directly. The drying behavior of the liquid as well as the selected process temperatures determine the structure of the primary particles (powder). As a rule, homogeneous particles, hollow bodies and often transitional forms are formed.
In spray drying, depending on process control and fine particle recirculation, intentional agglomeration effects can also occur. This also leads to a change in product properties.
Spray drying processes can be carried out in adapted fluidized or spouted bed systems or in synthesis reactors.
Product properties of powders from spray drying based on fluid bed, spouted bed or powder synthesis at a glance:
High
Porosity
Low
Particle Density
High
Specific Surface Area
Adjustable
Particle Size
Adjustable
Composition
Product examples
Carbon silicon anode material, spray drying, powder synthesis, REM image
The process of spray drying in detail
Liquids containing solids, such as solutions, suspensions or melts, are sprayed into a fluid bed, spouted bed or into the pulsating gas stream of the Glatt powder synthesis. Due to the high heat exchange, the aqueous or organic solvents evaporate immediately. The solids directly form small particles. These powders form immediately by drying from the spray droplets. The powders are usually formed by convective drying, starting from the outer shell of the droplets. No separate feed of raw materials is required.
From the product idea to production
Since spray drying processes start with the preparation of the liquid, we support our customers in developing the formulation and liquid preparation. The liquid can then be produced in a plant test at our technology center. Starting from laboratory scale, the product can be verified in pilot plants. Reliable scale-up enables the development of finished solutions on an industrial scale. Through contract manufacturing at Glatt, your new powders, pellets or granules can be manufactured, filled, packaged and delivered directly in agreed quantities. As a plant manufacturer, Glatt provides all services from project initiation, development and realization through to turnkey production in your own plant
Further information on this topic can also be found in the following publications:
Published article: ‘Particles in an onion look – Drying of liquids by fluid bed spray granulation (vs. Spray drying)’ PDF, German
Published article: ‘Dried to the point – Thermal processes in the fluid bed’ PDF, German
Published article: ‘Glatt Powder Synthesis – Pioneering Process for Groundbreaking Particle Synthesis’ PDF, English
Published article: ‘Outsourcing – Trust in competent partners’ PDF, English
Published article: ‘Spray agglomerating plant-based milk alternatives for optimised product properties’ PDF, English
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