Water Solution available

[Dave A]

I've mulled over a few challenges that don't seem to be mentioned so far. In particular, for a plant of the proposed scale - Can you imagine the complexity of the Environmental Impact Assessment Study.

I have two particular concerns. One of them is heat.

The transition from gaseous to liquid state is going to require the removal of a lot of energy in the form of heat - which has to go somewhere.
Where is this energy going to go?

The energy involved isn't trivial. Take a look at this table on the properties of saturated steam.
At atmospheric pressure (0 bar g, absolute 1 bar ) water boils at 100 ^oC and 417.51 kJ of energy is required to heat 1 kg of water from 0 ^oC to evaporating temperature 100 ^oC.
Another 2257.92 kJ of energy is required to evaporate 1 kg of water at 100 ^oC into 1 kg of steam at 100 ^oC.
Reversing this process means extracting all this energy.

Those little units I pointed to not only required a substantial injection of energy, it seems the heat energy being generated is just being dumped into the atmosphere. Not an option on a plant of the proposed scale methinks.

My second concern is that had the plant not extracted the water vapour, where would that water vapour have ended up eventually? I assume precipitation somewhere... that is no longer going to occur.

A drop in the ocean on small scale plants. A totally different story if you're looking to generate enough water to significantly impact a nation's gross agricultural output!

[Justloadit]

I think that the heated water solar parabolic system to filtrate sea water may be a better option, this will mimic the natural evaporation process the planet has been doing for millions of years.
The salt by product could be used for industrial applications to make chlorine, and these plants could be placed in remote areas in which there would be small impacts to the local environment.

[Dave A]

I think that the heated water solar parabolic system to filtrate sea water may be a better option, this will mimic the natural evaporation process the planet has been doing for millions of years.

You can also use the heat pump principle to take a significant portion of the heat extracted at the condensation stage and inject it into the evaporation phase of the process.

[Electrode]

I also agree if the impact is going to do more harm then good then it must be considered.

There is another option available that I found interesting.

Uploaded on Aug 13, 2008
Girja Sharan, a Hydrolic engeneer finds a way of solving the drinking water crisi with condensation

There is not much detail but I think it is possible to replicate.

[Justloadit]

Reminds me of this project done by an Italian designer Arturo Vittori called WarkaWater Tower

The village people are taught how to build this unit.

There are a lot of skeptics out there who do not believe this can work.
Any one who has lived in a rural area with corrugated iron roofs will attest to the amount of water collected on the roof before dawn every morning. A couple of litres at least.

[Electrode]

Reminds me of this project done by an Italian designer Arturo Vittori called WarkaWater Tower

The village people are taught how to build this unit.

There are a lot of skeptics out there who do not believe this can work.
Any one who has lived in a rural area with corrugated iron roofs will attest to the amount of water collected on the roof before dawn every morning. A couple of litres at least.

I would like to construct one myself. It looks simple enough and actually will look good in the garden. here is more information.

Warka WaterTowers Design

Included is a list of materials used.

[ATTACH=CONFIG]6123[/ATTACH]

It looks easy enough to build, but I wonder if a smaller version will work?

[Justloadit]

I would like to construct one myself. It looks simple enough and actually will look good in the garden. here is more information.

It looks easy enough to build, but I wonder if a smaller version will work?

It will definitely work, the amount of daily water yield may be little. Surface area of the mesh and cooling stage are directly proportional to the amount of precipitated water collected.

It will be a good experiment for you to actually experience the daily yield of water collected across the seasons. From the data collected, it can be deduced if the project will work under large scale construction.

[bones]

on this news clip they said
something like 25 gallons =
94.64 liters of water that is
not bad at all

[Electrode]

South Africa: Drought leads to failed crops, water shortages

The main street of this dusty South African town is lined with empty buckets, marking each residents' place in line as they wait for their daily water ration to be brought in by unreliable trucks.

Keeping watch over her buckets, Pulaleng Chakela sleeps in a wheelbarrow on the side of the road to save her spot in the line. The 30-year-old wraps herself in a little blanket as temperatures drop overnight, and asks a male friend to sit nearby for safety.

"If I don't wait here all night, the water will be finished," she said.

January 10, 2016 By Lynsey Chutel

Perhaps an active environmental study needs to be done. I am not sure if South Africa will fully recover from this drought as our weather patterns may be permanently altered. I don't know if we have the time to dally?

[bones]

http://www.islandsky.com/index.php?option=com_content&view=article&id=115&Itemid=3

Skywater’s Emergency Service Unit (ESU-20) is a crisis ready, emergency water generator that can deliver up to 900 gallons of pure drinking water daily. Skywater® ESU-20 co

ntains 3 Skywater® 300 atmospheric water generators, a 1275 gallon water storage tank equipped with advanced secondary water filtration, and a 30kw electric diesel generator housed within a customized Featherlite® 20’ft mobile container.


The Skywater® ESU-20 uses Island Sky’s patented air to water technology to produce fresh drinking water from water vapor in the air. Skywater’s adiabatic distillation process is unmatched in water vapor harvesting, converting available atmospheric humidity in the air into water.

In an average range of temperatures and humidity levels, the Skywater® ESU-20 will produce anywhere from 450 to over 900 gallons of water per day.

lookslike there is more then
1 company that is doing this
it is totally messed up that
our animals had to die while
this stuff was around

sucks

[Justloadit]

A 30Kwatt generator consumes approximately 11 litres of fuel per hour, at R12.5 equates to R138 per hour in fuel cost, never mind the maintenance cost that must be taken into consideration.

They reckon 900gallons or 3,400 litres per day, but they do not state the humidity and at what temperature and the amount of energy to get those numbers.

If we have an area of 3cubic meters at 22Degrees and 100% humidity, it will yield 2 litres of water per day.
Lets take a semi arid region, which may contain say 30% humidity, that will yield just over 0.5L of water per day.

So working on their numbers I would hazard a guess of approximately 1000 litres of water per day, and costing approximately R23.80 a litre of water, if not taking the cost of investment of the asset into consideration.

At the end of the day there must be some realistic figures to value the quality of the water producing system.
If one uses salt water and a RO process, it will probably cost R2 or R3 a litre, and the asset cost would be a fraction of the cost.

[Electrode]

A 30Kwatt generator consumes approximately 11 litres of fuel per hour, at R12.5 equates to R138 per hour in fuel cost, never mind the maintenance cost that must be taken into consideration.

They reckon 900gallons or 3,400 litres per day, but they do not state the humidity and at what temperature and the amount of energy to get those numbers.

If we have an area of 3cubic meters at 22Degrees and 100% humidity, it will yield 2 litres of water per day.
Lets take a semi arid region, which may contain say 30% humidity, that will yield just over 0.5L of water per day.

So working on their numbers I would hazard a guess of approximately 1000 litres of water per day, and costing approximately R23.80 a litre of water, if not taking the cost of investment of the asset into consideration.

At the end of the day there must be some realistic figures to value the quality of the water producing system.
If one uses salt water and a RO process, it will probably cost R2 or R3 a litre, and the asset cost would be a fraction of the cost.

I think cost will go down as the systems become more common and progress is made to allow them to run cheaper. Initial cost will always be high.

[Dave A]

When it comes to the Highveld, what we really need is someone to figure out how to turn that rising acid water in the old mines into potable water that could be used for drinking and agriculture.

[Justloadit]

The solution to clearing the mine acid water has been solved a good number of years back. The political will to implement is the delay.
Here is one company with a solution VEOLIA
There are a number of other companies

[bones]

i dont see why megafarmers
cant implement some of the
tech we see here

in the end they can benefit
from it or learn from it and
adapt it to work better