Titanium Dioxide (TiO₂)
Titanium dioxide processing typically involves wet milling followed by mechanical dewatering, resulting in a fine TiO₂ filter cake that must be dried while preserving particle size distribution and pigment performance. At this stage of production, drying technology must combine high evaporation capacity with reliable handling of cohesive, ultra-fine powders.
The Hosokawa Micron DMR flash dryer provides an efficient solution for drying titanium dioxide filter cakes or slurries. By combining dispersion, flash drying and particle classification in one continuous operation, the system enables TiO₂ producers to convert wet cake into a free-flowing powder while maintaining the particle characteristics obtained during wet milling.
Drying Titanium Dioxide Filter Cake
In many titanium dioxide production lines, the material leaves the filtration stage as a filter cake with moisture contents around 35% (wet basis). This wet material must be dried to a low residual moisture level without affecting the pigment’s particle size distribution or surface properties.
Drying TiO₂ filter cake can be challenging due to the combination of fine particle size, high moisture content and cohesive behaviour. The drying system must therefore ensure efficient moisture removal while preventing agglomeration or changes in particle structure.
Flash drying offers a practical solution for this application because the wet material is dispersed into fine particles before coming into contact with hot air. This rapid dispersion increases the available surface area for evaporation, enabling efficient drying while maintaining product quality.
Depending on feed moisture, particle size distribution and required final moisture, different drying technologies for TiO₂ filter cakes and powders may be considered.
Flash Drying Technology for TiO₂
The Hosokawa Micron DMR flash dryer is designed to dry slurries, filter cakes and pasty materials in a continuous process. Inside the dryer, a high-speed dispersion rotor breaks up the wet TiO₂ feed into fine particles, which are immediately exposed to hot drying air.
Because drying takes place while the particles are suspended in the airflow, evaporation occurs almost instantaneously and adhesion to internal surfaces is avoided. A rotating classifier located at the top of the dryer controls the particle size distribution of the discharged powder, ensuring that the product meets the required specification.
This integrated process makes it possible to perform dispersion, drying and classification in one compact system. More details about the Hosokawa Micron flash dryer are available on the corresponding technology page.
Process Performance
Flash drying enables high evaporation rates while maintaining stable particle characteristics. In titanium dioxide applications, inlet air temperatures of around 450 °C and outlet temperatures around 120 °C can be used to obtain a dry product. Under these conditions, TiO₂ filter cake with approximately 35% moisture can be dried to a final moisture content of around 0.3% wet basis.
Tests have shown that the particle size distribution of the product remains essentially unchanged compared with the wet feed material, maintaining a typical median particle size around 1 µm. Maintaining this particle size distribution is essential for pigment performance in coatings, plastics and other functional chemical applications.
Integrated processing systems
In titanium dioxide processing, drying is closely linked to upstream wet milling and dewatering as well as downstream powder handling requirements.
Hosokawa Micron therefore supports TiO₂ producers with flash drying technology as well as integrated powder processing systems for controlled handling, classification and process development.
Process Development and Testing
Because the behaviour of titanium dioxide filter cake can vary depending on upstream milling and filtration processes, pilot-scale testing is often recommended when designing a drying system.
At the Hosokawa Micron Test Centre in the Netherlands, flash drying trials can be performed to evaluate drying capacity, energy consumption and particle size distribution for specific TiO₂ materials. These tests allow process engineers to determine the optimal configuration before implementing a full-scale production system.
Learn more
Talk to our experts
Speak to our process experts about the optimal drying solution for your titanium dioxide application, from pilot-scale trials to full-scale powder processing systems.
Sustainable process technologies
Hosokawa Micron B.V. is committed to sustainable and responsible process technology. Our ISO 14001 certification covers key environmental aspects such as air, soil, energy, waste, water, noise and hazardous substances. With an EcoVadis Silver Medal, we rank among the top 3% of EcoVadis-rated companies in the special machinery industry.
