The Problem

Using conventional mixers and agitators, a number of problems can be encountered during production:

• Incorporation and dispersion of the powder becomes increasingly difficult as the viscosity starts to rise.
• Lumps cannot be readily broken down by agitation and long mixing times are required to complete solubilization.
• The vigorous agitation required to wet out the powder can lead to aeration problems.
• Inefficient agitation takes longer to achieve solubilization at temperature. A degree of shear is required to accelerate the process. 
• The heating stage of the process adds to costs and process time.

The Advantages

• Dispersing the PVA into hot water eliminates the heating stage, dramatically reducing process time.
• Rapid dispersion of powder eliminates operator error.
• Powder is fully dispersed before viscosity build-up commences.
• Any agglomerates are broken down by intense high shear mixing, resulting in accelerated solubilization and better batch consistency.

Typically PVA solutions are prepared in bulk. In-Line mixers are commonly used for very large volumes. In-tank mixers are also used depending on batch size, viscosity of end product, etc.