By Tommy Saunders, Senior R&D Engineer at AVEKA
Across nutraceuticals, personal care, and specialty chemicals, poor dissolution of powders remains a persistent challenge. Many high value powders in these industries are intended to be dissolved in solution, but their characteristics often make that process slow and difficult, requiring additional steps like heating or agitation.
This is where particle engineering comes into play. Powder characteristics like size distribution, morphology, surface area, and porosity can all impact dissolution behavior. By precisely controlling these characteristics, we can dramatically improve dissolution rates and downstream performance.
In the R&D Department at AVEKA, we encounter the challenge of poor dissolution all the time, and one of the most powerful techniques to solve this problem is fluidized bed agglomeration. This process converts powders which are difficult to dissolve (floating on the surface, clumping, forming fisheyes, etc..) into powders that can rapidly disperse into solution.
Fluidized Bed Agglomeration
Top spray fluidized bed agglomeration is a common technique to increase the particle size distribution of a powder, which can result in improved characteristics like flowability and dedusting. Another major advantage to this process is that the particles produced have a morphology that promotes rapid dissolution. The small starting particles are typically agglomerated into large, grape-like structures. These structures promote dissolution by pulling water into small channels via capillary action and using their large and irregular shape to break the surface tension of the solvent.
During the agglomeration process, water with an optional binder is sprayed onto a fluidized bed of powder. This atomized water/binder dissolves the particles locally to promote adhesion to one another, while heated process air dries off excess water to keep the powder dry and easy to handle. The gentle fluidization allows the powder to adequately mix and become uniformly agglomerated while not breaking down or creating large clumps.
Case Study: Turning a Poorly Soluble Premix into an Instantized Powder
Recently, the AVEKA R&D team worked with a customer developing a specialty powder premix. This product had great functional properties, but it required intense agitation and long times to dissolve into water for its final application. Additionally, the premix was thermally sensitive and contained multiple different components of varying particle size.
By leveraging fluidized bed agglomeration, we were able to grow the particles into the classic grape-like structure while drying at a temperature low enough to avoid negative impacts on the thermally sensitive components. The resulting powder immediately dispersed into water and dissolved for a consistent, balanced product. As added benefits, the customer noted the product flowed better than the starting material and was much less dusty.
Beyond Agglomeration: AVEKA’s Full-Service Offering
Fluidized bed agglomeration is often the key technology to enable better dissolution, but additional processing techniques are often required for the complete manufacturing process. Some other relevant process steps for this application include:
- Spray Drying for microencapsulation or rapid drying of slurries and solutions
- Air Swept Pulverization for controlled particle size reduction
- Dry Blending for uniform distribution of components or solubility enhancers
- Vibratory Screening for classification of particles by size
- Analytical characterization (i.e., PSD, BET surface area, moisture content, SEM) to validate performance
A wide selection of available unit operations and a fully equipped on-site characterization lab enable AVEKA R&D personnel to experiment with different process steps while getting rapid analytical feedback for optimization. With AVEKA’s approach, you can rest assured that your manufacturing approach is properly tailored to your product requirements.
If you’re working with a powder that’s difficult to disperse or simply want to explore how particle engineering can enhance your product performance, our R&D team is ready to help.
Submit an inquiry!