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sharshal
20-02-2007, 01:46 PM
Hi !

can someone help me with information about humidifiers for a sorting & grading area which will give out water droplets of maximum 1 micron size ? Here in India nobody gives anything lower than 5 to 10 micron droplet size.

Thanks !

Electrocoolman
20-02-2007, 02:02 PM
Hi sharshal,
Not sure of droplet sizes, but humidification can be by several different means...
Steam, pressure atomisation, ultrasonic.....
Have you thought about Evaporative Cooling.?
If your ambient temperature is high and your humidity is low, then would not evaporative cooling lower the temperature and at the same time raise the relative humidity?

Brian_UK
20-02-2007, 11:46 PM
Sharshal, steam or ultrasonic humidifers will produce vapour at the 1 micron level.

Are you wanting to install the humidifier to ductwork or is it to be freestanding?

sharshal
23-02-2007, 06:52 AM
Hi Brian & Electrocoolman,

Thanks for your replies. Here we have a specific case where temperature is being maintained at 15 deg C in the sorting & grading area (meant mainly for apples / pears). As such, we require to cool the area using a cooling coil. With WB temperatures close to 25 deg C evap cooling is pretty much out of the picture.

We have looked at options of disc type humidifiers and nozzle type humidifiers (fogger type), but both of these have committed a minimum droplet size of 5 ~ 10 micron.

The client is insisting on 1 micron droplet size. Are you aware of any companies who manufacture such humidifiers ? We can look at sourcing from any location around the world.

Brian_UK
23-02-2007, 08:31 PM
Vapac make steam humidifiers, details here....
http://www.eaton-williams.com/vapac/products/

If you have access to steam then try these, a bit more local...
http://forbesmarshall-inc.com/Company.asp
or here ?
http://www.trade-india.com/Exporters_Manufacturers/Indianexporters/Consumer_Electronics/Humidifier

Electrocoolman
23-02-2007, 11:40 PM
Hi Sharshal....one other question you need to ask / answer is: what is the quality of the water supply like....clean, pure, minerals present, hard (calcium), soft etc. This will determine if you need to quote for filtration / treatment and also what type of boiler you need to specify....Resistive or Electrode.

Hope this helps.

sharshal
26-02-2007, 02:22 PM
Thanks again, Electrocoolman & Brian !

As I understand from your inputs, the only way to get humidification less than 1 micron size is using steam ! Am I correct ?

Now we don't really have boilers at this site ! There is a water softening plant, so quality of water should not be such an issue.

If boiler is compulsory, then the whole situation takes a new turn ! :) In such a case, I would simply be able to put across this fact and get done with 5-10 micron humidifiers which would be a lot simpler !

Andy
26-02-2007, 09:47 PM
Thanks again, Electrocoolman & Brian !

As I understand from your inputs, the only way to get humidification less than 1 micron size is using steam ! Am I correct ?

Now we don't really have boilers at this site ! There is a water softening plant, so quality of water should not be such an issue.

If boiler is compulsory, then the whole situation takes a new turn ! :) In such a case, I would simply be able to put across this fact and get done with 5-10 micron humidifiers which would be a lot simpler !

The humdifier has in this case an electrode boiler as an intergral part of the hummidification unit. It all comes as a box;)

Kind Regards Andy:)

Electrocoolman
26-02-2007, 10:59 PM
Sharshal,
Have a look at:

www.carel.com (http://www.carel.com)

the spare boiler 'pots' are easily replaceable and I believe a lot cheaper than some other makes. I dont know if they are available in your part of the world.

MCP
15-04-2007, 10:01 PM
You might consider two ways in which to increase your humidity in the sorting area. One is to use what is sometimes called a wet air cooler. The configuration that I know is a normal evaporative cooler but the bare pipe coil is the evaporator. The recirculating spray water is chilled by the low temperature coil and thus cools and humidifies the incoming air. The cooler can thus be positioned such that the air in the room is circulated through the cooler. Chilling and humidifying then happens at the same time. Does not really answer your drop size problem, but maybe using this method, it is no longer an issue.
The second option is to use an evaporative pad which is a corrugated material that absorbs water and once saturated, humidifies air that passes through it without any aerosol formation. The product is used as a precooler for the larger dry coolers marketed by BAC. Some variation of this may be available from Munters.

Samarjit Sen
16-04-2007, 06:37 PM
Sharshal,

For proper humidification in Precooling Rooms , High Humidity Cold Stores and Pack House for Fruit and vegetable units, you require Adiabatic Humidifier. These disc type humidifiers etc and the Coils that are being generally used in our country does not give you the desired results.

Contact Amoto Engineers in Mumbai. They are making adiabatic humidifiers with water droplets at 3 microns. They can create RH up to 98%. I have used there units in a number of Precooling and Packhouse Projects, where it is very successful.

Our complete system is quite different from the ones that are being generally used in our country. Fortunately these have been found very effective

sharshal
11-05-2007, 12:55 PM
Thanks MCP and Samarjit Sen !

I saw the site for Amoto Engineers, Mumbai, they have 5-10 micron droplet size for their system

actually what we're looking for is with 1 micron size, as its a tender requirement. As has been mentioned in one of the earlier conversations (by Brian_UK), and from what I gather from the market, 1 micron can be achieved using either steam humidifiers or ultrasonic humidifiers only. Both these are, unfortunately, not readily available in India.

Sharshal

Brian_UK
11-05-2007, 07:35 PM
Hi Sharshal, have a look at these people, JS Humidifiers, who adverise dealing in over 80 countries..
http://www.jshumidifiers.co.uk/

There website also has a lot of downloadable files detailing their products which may be of use.

Good luck in your quest to resolve this one:)