Ethadry 3A Molecular Sieve: Properties and Their Effect on Ethanol Production
How do you pick the best 3A molecular sieve for your operation. They are not all the same, far from it.
Critical properties vary from vendor to vendor. All these properties are interdependent. For instance -superior crush can have a negative effect on mass transfer and working capacity. Another factor – TDS is what a manufacturer intends to do, CofA’s is what a manufacturer really does. Ask for multiple sequential CofA’s or statistical analysis of production history. Beware of “Grand Lotting”, This is when a manufacturer has an inferior lot and blends it in to create a new lot that meets (barely) the specifications. Look for vendors with small lots to avoid this. Ask them! Watch out for “false pore closure” to reduce do-adsorption – damages mass transfer rate and working capacity. Ask your vendors!
Properties and Their Effect on Ethanol Production
Diameter / Particle Distribution
Bead size and distribution have a dramatic effect on fluid dynamics and mass transfer rate- this affects durability, pressure drop and subsequent working capacity – look for a very narrow 4×8 mesh particle distribution with minimal heads and tails
Bulk Density
The higher the bulk density the more pounds go into a fixed volume. Since water capacity is a % w/w this means overall higher capacity for a fixed volume.
Crush Strength
Physical pressure required to break a bead. Higher is better but need to look at the effect on mass transfer – too high a crush – reduced mass transfer rate, reduced mass transfer rate – may be an indication of thermal pore closure
Static water adsorption
Not the same as working capacity but an indicator of working capacity. This is the maximum amount of water adsorbed over a 24 hr period at a specified humidity
Working Capacity
How much water is adsorbed per pound sieve in each cycle. The true practical measure of the work being done by the sieve, empirically derived from the isotherms and verified in operation. It can be derived from the heat generated in the adsorption cycle.
Ethanol Co-adsorption
All molecular sieve begins life as a 4A crystal, then ion exchange the 4A is converted to 3A. 100% exchanges are impossible but can be ion exchange through manufacturing techniques. The lower the co-adsorption the less ethanol goes to recycle. This must be achieved through ion exchange. Some use thermal pore closures, but thermal pore closure damages the crystal and has a negative effect on mass transfer rate and other properties.
Contact HengYe Inc.
If you need further assistance or guidance on Ethanol 3A Molecular Sieve, feel free to contact us here at HengYe. Call us at (844) 308-3271 for any inquiries regarding our products and services.
