Specialty & Fine Chemicals - Homogenization
Suspensions are a mixture where a material is dispersed in another one: generally there are solid elements like powders or pigments dispersed in a liquid substance.
Rather than solutions which are transparent, suspensions are cloudy and murky and they require the application of mechanical energy for their preparation.
The dispersion process most often involves the reduction of agglomerates to their primary particle size and the homogenizer can produce a very fine dispersion of particles, better than any another devices, which require long processing time.
High pressure homogenizers also make unique changes to many products, for example in the cellulose application it defibrillates the fibers to increase its water-binding tendency.
GEA offers tailor made solutions for new application developments such as the nanocellulose, in which the production principle is the liberation of long micro-fibrils from the fiber wall. Micro-fibrillated cellulose is a mixture of nano-fibrils, fibrillary fines, fiber fragments and fibers, but the majority is nanofibrils. By passing through the homogenizing valve, at very high pressure, the high shear stress delaminates the fibers fragments,this way the fibers are getting finer in width maintaining the original length.
It is demonstrated that homogenizer technology led to smaller particles compared to rotor/stator one. High pressure homogenization is normally carried out in conjunction with high shear grinders or refiners. Comparisons of the particle size and particle size distributions obtained with a high shear mixer, clearly shows that smaller particles and tighter distributions are achieved to those having under gone high pressure homogenization. For this reason high pressure homogenization (from 600 up to 1500 bars) is the technology selected for the final step of the manufacturing program, it is capable to produce NFC gels at industrial scale.