Deionized water misted into space 1

[floppytunafish]

Hello,

Not quite an HVAC question but it fits into the MEP industry. I have a university client who needs to provide DI water to some greenhouses. The DI water will be misted into the space for plant watering. There are some existing galvanized steel benches in the greenhouse and the walls are 8" CMU blocks. Would the benches and walls need any protection from the DI water (corrosion, etc.)?

Thank you for your help

 

[dbill74]

Hello floppytunafish,
Unless the spray nozzles are directing their spray right at the benches or CMU wall (within 12" and pointed at bench/wall) you will be fine.
I am curious why the need for DI water to generate a spray for watering plants. As soon as the water leaves the nozzles it is going to starting interacting with the air and any particulates in the air effectively making the spray non-DI. If the university really needs to water the plants with DI water, a stream or drip system directing the water direct to the plants would do better.

Running the irrigation water through a softener or some filters would be much easier and cheaper.
WM

 

[floppytunafish]

dbill74, thank you. I hear what you are saying. They are supplementing the misters with a drip system.

 

[EnergyProfessional]

with sprayers you will have some spray-off and high humidity, so corrosion will be a given to some extent. The galvanized will work fine if you don't spray on it, but won't last forever. After some years you can see which areas get more or less water.

 

[IRstuff]

DI water will pretty much instantaneously become acidic from dissolving CO2

TTFN
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[RossABQ]

Are you sure it isn't Reverse Osmosis (RO) water? I too am baffled by the thought of using deionized. RO makes sense if the water is full of minerals that might plug the jets. True DI water would be aggressive against many types of plastic piping.

 

[DBronson]

floppytunafish:

Another problem with DI water is that it doesn't remove pathogens. I'd be very concerned about legionellosis - especially if they are misting the water. Most of the greenhouses we've worked on use RO water.

Regards,

DB