Aussies believe in global warming...

[jayman]

Originally Posted by patsparks

Yep, knew all that, I used to repair air conditioners. I meant use water as the refrigerant in a vacuum on the low pressure side. I'm guessing it would cause cavitation and corrosion.

The water may freeze, causing problems with piping. The biggest concern is as you stated, corrosion. For chiller assemblies and cooling towers on rooftops of commercial buildings, you have to monkey around with a lot of different chemicals to minimise corrosion

Nu-Calgon: Products: Cooling Tower Water Treatment

Probably not much demand for central boiler systems where you live, but they're literally a life-and-death deal here. You will experience scale, rust, and nasty corrosion of expensive boiler parts unless proper chemicals are treated in

Nu-Calgon: Products: Boiler & Closed System Water Treatment

Perhaps the biggest drawback to using plain old water is efficiency. The dedicated refrigerants are *much* better thermal efficiency. Eg, even in the chemical industry, for heat exchangers they will use a process working fluid instead of water, to minimise corrosion and increase efficiency

http://www.dynalene.com/pdf/DySF.5.2.07.pdf

[jayman]

Originally Posted by patsparks

Here is a picture of my brother at work, well he is most likely ordering a pizza for dinner but it looks like a business call.

A nice clean shiny control room. The photo resolution isn't very high though. Is that a Siemens Simatic PCS7 or an Emerson PlantWeb control system he is using??

Originally Posted by patsparks

Shhhhh! don't tell anyone, that's also Bev's husband.

Looks like the Sparks Brothers have good luck with finding women!

[jayman]

Originally Posted by DaveinOlyWA

OK Jay, please dont hammer me on terminology!!

Ok, I won't

Though I may tease you just a little bit ...

Seriously, I agree with most of your rant

[jayman]

Originally Posted by bevspark

He is my own Homer Simpson, he's an environmentalist isn't he?

Yes, I can see the Sparks Brothers have had good luck with their women ... some guys have *all* the luck

[hyo silver]

Originally Posted by jayman

...In the case of an Alkali plant, the recycle water is generally used in other parts of the plant...A brand new plant, a very effective arguement could be made for having different applications - say irrigation - for the water assuming it isn't contaminated with heavy metals...

Sounds better to 'remove the water' before the limestone is added to the mix. Assuming a relatively unpolluted source of seawater, would heavy metals and other contaminants still be a problem? How about a 'first stage' process with only seawater and sunshine as the inputs? It could produce clean water, and provide brine as an input to the rest of the alkili production. This could be part of a new plant, or a replacement for the evaporation ponds of an older one. A smaller scale version might be useful in the third world, or anywhere else the water would be the most valuable commodity.

[jayman]

Originally Posted by hyo silver

Sounds better to 'remove the water' before the limestone is added to the mix.

If you do that, the chemical reaction will no longer work

Originally Posted by hyo silver

Assuming a relatively unpolluted source of seawater, would heavy metals and other contaminants still be a problem?

The problem isn't the water, it's the feedstock source. Limestone sources in North America can have ferrugenous mercury, sometimes in very high concentrations. I'm unsure if Australia has this issue, perhaps Pat or another Aussie can chime in

The cement industry recognizes that mercury emissions from lime kilns are a problem.

EPA urged to control mercury from cement kilns

Surprisingly, most folks are completely unaware that mercury can be present in limestone

Originally Posted by hyo silver

How about a 'first stage' process with only seawater and sunshine as the inputs? It could produce clean water, and provide brine as an input to the rest of the alkili production.

Although that probably wouldn't meet the demands of a modern Alkali facility, it would certainly require much less thermal energy input. In the third world scenario, this process would absolutely work, although potable water output would be modest by current standards

[hyo silver]

Originally Posted by jayman

If you do that, the chemical reaction will no longer work...

But if the aim is to produce water and electricity...

...Although that probably wouldn't meet the demands of a modern Alkali facility, it would certainly require much less thermal energy input. In the third world scenario, this process would absolutely work, although potable water output would be modest by current standards

My original intent was to learn about producing water, and perhaps electricity, from seawater and sunshine. Asking about the usability of the leftover salt, I've learned something about the Alkili industry. Enough, I think, to conclude that the two aims really aren't all that compatible.

The third world scenario seems closest to what I was thinking. Something robust that will work in remote areas with minimal intervention, to provide people with clean water and some electricity where there is none.

[jayman]

Oh, gotcha. Guess I went a wee bit off topic