7 replies to this topic

[Carlo717]

I have a slurry/suspension? of TIO2, waste metals and water with a solid chosen to be around 70%. I need to dry this to as low as possible for storage so I chose around 0.5% moisture via a spray dryer. I would of chosen fluid bed with some sort of pre concentration unit but it's too late now and I think it will be too much for me to design. My issue is, I have no idea where to start and this needs to be done for 2 weeks time! I have the Masters book but it's still going over my head.

[breizh]

http://www.nzifst.or...ions/drying.htm
Hi,
Let you consider this resource to support your query.
Breizh

Edited by breizh, 03 March 2012 - 07:18 AM.

[Carlo717]

Hi,
Let you consider this resource to support your query.
Breizh

Which resource?
Thanks.

[breizh]

sorry !

[breizh]

http://www.niroinc.c...ent_systems.asp

I've added some reference for spray dryer .
Breizh

[Carlo717]

http://www.niroinc.c...ent_systems.asp

I've added some reference for spray dryer .
Breizh

Thank you! Is my procedure of design :

Set inlet Temp of TiO2 slurry, moisture content (30%) ...
Define required outlet moisture content of the dried TiO2 (0.5%)
Work out flow rate of dry air, and temp to reduce moisture content to require amount.
Work out energy required to heat up air to defined temp from the outside air temp.

from these work out the size of the drier needed and then look into details such as atomization etc../

[breizh]

Always start with mass and energy balances .
Breizh

[Carlo717]

Always start with mass and energy balances .
Breizh

I have managed to make some progress on a mass balance thanks to the links you gave me! The thing that is getting me now is the energy.

If my feed is at 150C and I use air at 150C to dry it with then it has quite a low efficiency. If I increase air temp to 250C it's much higher.... but with this does the feed first get heated up to 250C using some of the air energy and then vaporize? Or does it simply stay at 150C?