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samiam
12-02-2008, 06:54 PM
Question 1

I am busy with the design of a green building. One of the methods identified to utilise the condensate water as grey water for the toilets.

What methods could I use to calculate the amount of water removed from the air per day?

Thanks.

nike123
12-02-2008, 07:06 PM
Theoretically, by applying Mollier chart and some supposed conditions an quantities of cooled air.
Practically, you have to many varying inputs (temperature, humidity, air quantity.....).

TRASH101
12-02-2008, 07:43 PM
Because of the limitations and varied quantities of condensate you would be better off having a compensated conventional system perhaps with a float switch and solenoid. Dont know what water by-laws but grey water storage might have micro biological considerations

dsp
12-02-2008, 10:36 PM
Hello Samian,
I know this sounds rough but as a very general rule I have used the old (1Hp of cooling produces 1 litre of condensate per hour). Its probabley overkill but it has worked.
It hasn't failed yet.

I would wait for a more accurate way of calculating condensate from someone else though.

dsp

Brian_UK
13-02-2008, 01:13 AM
Have a look at page 8 of this Sauermann condensate pump handbook.

Note that the liquid quantity is in US gph.

http://www.sauermann.us/pdf/Handbook_2006_new.pdf

Tesla
13-02-2008, 07:56 AM
Here in Sydney I hear they are using condensate for cooling tower makeup, and for the toilets many buildings are going for the waterless uranals - they stink a bit much for me.

superswill
14-02-2008, 09:18 AM
0.5-0.8 litters per hour hour per kw of duty,i read the other day,also room humidity will be a major factor

samiam
14-02-2008, 11:06 PM
Hi Guys - thanks for the thoughts and the rules of thumb.

I should have elaborated further on the refigerated zones, there are Low (at -20C), Medium temp zones (0C and 10C).

My preliminary condenstate water calc was base on the amount of ice buildup on the coil (up to the defrost). Any thoughts on this method?

Core4 Guy
17-02-2008, 09:29 PM
Question 1

I am busy with the design of a green building. One of the methods identified to utilise the condensate water as grey water for the toilets.

What methods could I use to calculate the amount of water removed from the air per day?

Thanks.

I like your thinking. Condensate is one thing, condenser water cycles are another. We have been using a dolphin treated evap condensers water as grey water for toilets. We have a pressure storage tank that fills on need. Taking water from the evap condenser, while reducing the hardness levels. Great for both sides.

Oregon Jim
05-03-2008, 06:16 AM
This is a bit off subject, but your question about collecting water from the air reminded me of a water collection system the military is looking into to "tap the air" for water.

A large bank of vessels filled with desiccant draws water from the air, and when the desiccant is regenerated the water is condensed and filtered for drinking. It is much cheaper and energy efficient than trying to condense water with just refrigeration.

sterl
15-04-2009, 06:47 PM
Meltwater to the toilets....Has a tickle tendency to it. Believe it has been done at some ice rinks with the snow melt from the re-surfacing.

Used to run meltwater back to a "cold well" in the evap condenser tank, cooled the air compressors and CA driers with it, return was to the "warm" side.

I have also seen it used to dehumidfy receiving or ante rooms, docks, etc. using a "waste" halocarbon finned coil and a poly tank connected directly to the drain. Q & D +1C Dew Point air.

sterl
15-04-2009, 08:15 PM
Sorry, off topic.

A lot of studies and papers on the amount of water generated by HG Defrost to help understand the corresponding HS load. Many rules of thumb concerning face area of coil, initial coil temperature and similar.
Niagara No Frost has a collection of case studies based on the energy usage & cleanliness of their equipment. Some of that on their website; some more at :
www.irc.wisc.edu/ASHRAE-TC105/programs/Liquiddesiccant.pdf


Very detailed but based on actual measurements: Wisconsin Doctorate thesis...


minds.wisconsin.edu/bitstream/handle/1793/7606/hoffenbecker_04.pdf?sequence=1

The parties in a prolonged study on the effectiveness of hot gas defrost include R. A. Cole; R. Sherif; A. Al-Mutawa.

Some case studies also with Munters and Harris in terms of process spaces particularly.

nh3wizard
16-04-2009, 07:36 PM
On our penthouse units we run the condensate lines back to the evaporative condenser and reuse the water that way,.

Abby Normal
17-04-2009, 05:14 AM
outside of slime and biologicals on the cooling coil that is distilled water. There are commercially available systems to turn it into potable water

Its all about climate. I have some 2250 CFM 100% outside air units, that will produce about 400 US gallons a day in the humid rainy season

desA
17-04-2009, 05:26 AM
There are commercially available systems to turn it into potable water

Could you please provide some links to such commercial systems? This would be very useful to me. Many thanks.

Segei
18-04-2009, 12:51 AM
Sorry, off topic.

A lot of studies and papers on the amount of water generated by HG Defrost to help understand the corresponding HS load. Many rules of thumb concerning face area of coil, initial coil temperature and similar.
Niagara No Frost has a collection of case studies based on the energy usage & cleanliness of their equipment. Some of that on their website; some more at :
www.irc.wisc.edu/ASHRAE-TC105/programs/Liquiddesiccant.pdf (http://www.irc.wisc.edu/ASHRAE-TC105/programs/Liquiddesiccant.pdf)


Very detailed but based on actual measurements: Wisconsin Doctorate thesis...


minds.wisconsin.edu/bitstream/handle/1793/7606/hoffenbecker_04.pdf?sequence=1

The parties in a prolonged study on the effectiveness of hot gas defrost include R. A. Cole; R. Sherif; A. Al-Mutawa.

Some case studies also with Munters and Harris in terms of process spaces particularly.
Optimization of hot gas defrosting is complicated issue. This master's thesis just touch the surface.

Abby Normal
26-04-2009, 01:15 AM
Could you please provide some links to such commercial systems? This would be very useful to me. Many thanks.

Munters was one vendor, i looked on the site but I am afraid you will have to contact a representative

Abby Normal
26-04-2009, 04:51 AM
http://www.achrnews.com/CDA/Archives/dd24dc872b06a010VgnVCM100000f932a8c0____