Below are some common questions you should ask to choose the right dispersant for your laboratory needs.
Does the application require a disperser or mixer?
Dispersers are required when solid particles are dispersed in a liquid to create a colloidal suspension. If the solid dissolves easily in water like sugar, then a simple air or electric mixer is fine.
What particle size is required for the application?
If the final particle size requirement is 20 microns or larger, a high shear vertical disperser is sufficient. One caveat is that the mill base (a mixture of solid material and liquid) should have a viscosity greater than 30 cm. The mill base needs to have enough internal friction to create a "donut effect" when dispersing. Low viscosity mill base systems require the use of grinding media. Organic pigments often require grinding media to achieve the proper particle size. The main particle size of organic pigments is below 20 microns, and aggregated organic particles require more energy to decompose. VMA-Goetzmann has several media mill models: SL-horizontal bead mill, TML basket mill and APS system.
What size disassembly is required?
This is especially important in high shear vertical dispersers. Selecting a laboratory disassembler with a motor design that is too small for the application can cause the motor to overheat and shorten the life of the disperser. Proper motor sizing is when most decentralized applications use no more than 80% of the motor's design capacity. Mill base and viscosity are key factors in selecting the correct motor. Mill base quantities with viscosities between 3,000 and 5,000 cm require a 1.0 HP dispersing motor. If the viscosity of the mill base is greater than 5000 cm, the mill base should be reduced. Volumetric capacity is an important criterion for choosing the right media mill. Please contact your BYD-Gardner representative for advice.
Other considerations are:
Does the diffuser need to be explosion-proof?
If the diffuser goes into the hood, what is the maximum height available?
What safety equipment or features are required?
Larger teardown models may require a voltage transformer?
Is there a minimum or maximum motor shaft speed requirement?
