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Author Topic: Water distillation using coal-steam power plants?  (Read 2218 times)

Offline McKay

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Greetings. Another thought of mine seeking an answer/ discussion - coal power stations use the heat of burning coal to boil water to super hot steam to rotate a turbine for electric current generation. The water is usually conserved - condensed and directed to be boiled again, right? Why not direct the boiled water, that is now kinda super clean, to be collected as drinking water and pump in regular sea water in the boiling chamber?


 

Offline syhprum

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Re: Water distillation using coal-steam power plants?
« Reply #1 on: 16/06/2014 00:30:47 »
To generate the required superheated steam for the turbine pure distilled water is required trying to use sea water would quickly destroy the whole plant
 

Offline Bored chemist

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Re: Water distillation using coal-steam power plants?
« Reply #2 on: 16/06/2014 12:57:55 »
The water quality requirements in high pressure steam boilers are much higher than those for drinking water.
 

Offline homebrewer

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Re: Water distillation using coal-steam power plants?
« Reply #3 on: 26/06/2014 02:25:48 »
Two more concerns :

Modern boilers use some kind of water treatment for the boiler feed water, which  renders the water unsave for human consumption.

Furthermore, current environmental concerns dictate to reduce the ionosation of drinking water, so water distillation in steam boilers is not such a good idea for the environment after all.
 

Offline alancalverd

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Re: Water distillation using coal-steam power plants?
« Reply #4 on: 26/06/2014 08:50:59 »
When British water was publicly owned, the stuff that came out of your domestic tap was of "basic industrial" quality, fit for most non-recirculating machinery (including railway engines) and every human use except dialysis or injection. Thanks to the EU's requirement for privatisation, it is now only of "potable" quality and contains all sorts of stuff that you wouldn't want on a lathe, never mind a power station.
 

Offline Bored chemist

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Re: Water distillation using coal-steam power plants?
« Reply #5 on: 26/06/2014 20:00:06 »


Furthermore, current environmental concerns dictate to reduce the ionosation of drinking water,

What do you mean?
 

Offline CliffordK

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Re: Water distillation using coal-steam power plants?
« Reply #6 on: 27/06/2014 07:11:26 »
Because a modern power plant doesn't use saline, or brackish water, doesn't mean that it would not be possible.  Many modern ships distill their own water.

There are grades of metals that are fairly resistant to salt water.  Perhaps one would design a mechanical cleaning mechanism for inside the boilers.
 

Offline Atomic-S

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Re: Water distillation using coal-steam power plants?
« Reply #7 on: 28/06/2014 06:04:20 »
It seems to me that I have heard of joint power-distillation plants having  been done, although I do not know the engineering particulars.  However, it is not a formidable conceptual challenge; the turbine water will have to be cooled, and to do that, it could go through a heat exchanger and heat brackish or sea water as part of a probably significantly more complex system of harnessing the waste heat for distillation of water, even if not the specific water running through the turbine.
 

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Re: Water distillation using coal-steam power plants?
« Reply #7 on: 28/06/2014 06:04:20 »

 

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