Plant Steam for humidification

[grim900]

Looking at a low grade clean room (ie less than Grade D, Class 100,000), for tablet forming. Air conditioning is only filtered to EU9. However, client has specified the use of Clean steam for humidification, generated from purified water supply.

Bearing in mind that the rh required is only 37% the humidity load is minimal especially since the system is approx. 80% recirc. Also, the 20% fresh air will contain contaminants which won't be removed by an EU9 filter. It seems to me that use of clean steam is over the top unless anybody can advise particular problems with injecting plant steam into the air stream.

Any advice gratefully received. Thanks.

 

[azertyuiop]

If you still have to supply your tender , maybe you can give him also a cheaper alternative to his request , and make him aware his request for steam humidification won't solve his contamination issue due to the fresh air intake and low steam volume requirements.

He probably is taking safe bets , just to avoid to be taken by his own QA/QC department later on.

 

[Joesteam]

I am no expert on clean rooms, but you can 'clean' plant steam with a separator and filter (down to 1-micron). Much less expensive than a clean steam generator. Look at:

http://www.spenceengineering.com/Handbook/scrub.pdf

 

[ChasBean1]

Joe, is the main intent to filter water droplets? Would that filter remove volatiles such as morpholine used for pH control? That's where I'd be concerned. You might feed filtered "clean" steam to the space with a pH of 9.5 due to morpholine, which smells like a combination of fish and ammonia. I don't know what airborne concentration this would cause but I would still guess it to be below any OSHA/NIOSH limits and maybe even below the odor threshold.

Grim, I would say the decision rides on what type of water treatment is employed. You can take away the morpholine and reduce phosphates (which can also contribute to odor even if they don't carry over) and watch your plant degrade a lot quicker, or you can supply clean steam. It may be a good application for an electric humidifier. Dristeem has them. You can probably use an RO or RO/DI water makeup if the building has it.

 

[grim900]

Thanks for your help everybody. Electric humidifiers are used on the site at the moment (Carel HeaterSteam type) & I think thats the way the customer will go, but just wanted some back up advice before I discussed alternatives with him.

Thanks.

 

[steam4]

grim900,
Here's another choice for you:

http://www.armstrong-intl.com/products/humidifiers/hnosteam.php3

 

[lilliput1]

Minimizing the use of Amines by using deakalizers in addition to water softening will allow use of boiler steam for humidification. Otherwise use electric Deionized water to steam or steam to clean steam humidifier.