> how about generating electricity with hydropower
I am intrigued to hear how the author plans to take water from sea level then use it to generate hydroelectric energy.
The Dirty Truth About Turning Seawater into Drinking Water
81–90 of 132 posts
Re: The Dirty Truth About Turning Seawater into Drinking Water
#82Earlier quoted context omitted.
Yes, just like exhaled breath is a waste product full of C02 and containing very little oxygen. If other people had to breath that they would become very sick or even die.
Actual question, how many time can air be breathed? I think you can live on second-hand breath.
Well that's how CPR works ... I can't remember the details ... it's many many years ago I studied first aid but I think it's something like 1/3 of the Oxegen gets used, so when you're giving the kiss of life you're imparting the remaining 2/3
Re: The Dirty Truth About Turning Seawater into Drinking Water
#83> In fact, the study concluded that for every liter of freshwater a plant produces, 0.4 gallons (1.5 liters) of brine are produced on average.
I hate that they mix the units here. Why not "for every liter of freshwater a plant produces, 1.5 liters of brine are produced" or "for every gallon of freshwater a plant produces, 1.5 gallon of brine are produced" or even "for every unit of freshwater a plant produces, 1.5 units of brine are produced"
Also, producing more brine would make the brine less concentrated and less harmful - it would be better not worse.
Re: The Dirty Truth About Turning Seawater into Drinking Water
#84Earlier quoted context omitted.
Yes, just like exhaled breath is a waste product full of C02 and containing very little oxygen. If other people had to breath that they would become very sick or even die.
Actual question, how many time can air be breathed? I think you can live on second-hand breath.
I'd be quite dangerous and very uncomfortable: exhaled air contains ~4% CO₂, 16% O₂ and is at roughly 100% humidity.
* at 4% CO₂ you'll be suffering from moderate CO₂ toxicity (narcosis, dizzy spells, increased heart rate & blood pressure, mild shortness of breath, exaggerated response to effort)
* at only 16% O₂ (but assuming atmospheric pressure), you're well into chronic hypoxia land, not quite sure lethal but not far, the hyperventilation from CO₂ poisoning will make this slightly better but nowhere near good
* the combination of hypoxia and CO₂ poisoning will make effort (let alone exercise) possibly to probably lethal
* the extreme levels of humidity will make the entire thing even worse as you'll have a hard time cooling down
You can probably live in this situation for a few days, but the CO₂ levels alone would make it lethal past a few weeks, the combination of all factors means likely no more than a pair thereof, at best.
Re: The Dirty Truth About Turning Seawater into Drinking Water
#85Earlier quoted context omitted.
Yes, just like exhaled breath is a waste product full of C02 and containing very little oxygen. If other people had to breath that they would become very sick or even die.
Actual question, how many time can air be breathed? I think you can live on second-hand breath.
CO2 concentrations above 7% are enough to suffocate you even if there is otherwise ample oxygen.
Re: The Dirty Truth About Turning Seawater into Drinking Water
#86Sure, the high salt concentration kills sea life for a couple hundred meters around where the waste comes out, but compared to the total size of the ocean, I'd imagine the affected area would be TINY. Once you get to a larger area it'd be totally diluted by the normal salinity seawater. Why don't you just build a pipeline to put the dead spot a couple miles away from shore, far away from economically important beache…
That is what I intuitively thought, until I learnt that salinity in the Persian Gulf (a huge body of water connected to the ocean) is up significantly due to desalination. Salinity has risen 50% over the last two decades. See e.g. https://financialtribune.com/articles/people-environment/434...
Simple math will tell you that this increase cannot be due to desalination. Look:
Volume of the Persian Gulf = Area (251,000 sq km) * average depth (50 m) = 12,000 cubic km approx.
Total amount of desalinated water produced in the world, per annum = 86 million cu. m = 0.086 cu. km,
So if all of the world's desalinated water was taken from the Persian Gulf, for 150 years, the salinity would only increase by 0.08*150/12000 = 0.1%, roughly.
Edit: the entire article is bad, and the headline is sensationalist bullsh#t.
Re: The Dirty Truth About Turning Seawater into Drinking Water
#87> In fact, the study concluded that for every liter of freshwater a plant produces, 0.4 gallons (1.5 liters) of brine are produced on average. I hate that they mix the units here. Why not "for every liter of freshwater a plant produces, 1.5 liters of brine are produced" or "for every gallon of freshwater a plant produces, 1.5 gallon of brine are produced" or even "for every unit of freshwater a plant produces, 1.5 un…
> Also, producing more brine would make the brine less concentrated and less harmful - it would be better not worse.
Producing more brine, by diluting it, still would require something to dilute it with.
The most obvious, non toxic, choice would probably be water, but the whole exercise is about getting water in the first place.
Re: The Dirty Truth About Turning Seawater into Drinking Water
#88I see this as an opportunity. Before you dilute the brine with sea water and pump it back into the ocean, ideally you remove the microplastics and perhaps some other problematic substances and thus clean up the ocean.
Unfortunately the volumes of "cleaned" brine are just not significant. See my comment elsewhere in the thread.
Re: The Dirty Truth About Turning Seawater into Drinking Water
#89Earlier quoted context omitted.
That is what I intuitively thought, until I learnt that salinity in the Persian Gulf (a huge body of water connected to the ocean) is up significantly due to desalination. Salinity has risen 50% over the last two decades. See e.g. https://financialtribune.com/articles/people-environment/434...
Simple math will tell you that this increase cannot be due to desalination. Look: Volume of the Persian Gulf = Area (251,000 sq km) * average depth (50 m) = 12,000 cubic km approx. Total amount of desalinated water produced in the world, per annum = 86 million cu. m = 0.086 cu. km, So if all of the world's desalinated water was taken from the Persian Gulf, for 150 years, the salinity would only increase by 0.08*150/1…
It doesn't need to be responsible for all of the change, it might only be one among many contributing factors like climate change.
In that context, it would be shortsighted and naive to pretend it couldn't have any impact at all even on bigger and longer scales.
Re: The Dirty Truth About Turning Seawater into Drinking Water
#90Earlier quoted context omitted.
Yes, just like exhaled breath is a waste product full of C02 and containing very little oxygen. If other people had to breath that they would become very sick or even die.
Exhaled air consists of 78 percent nitrogen, 16 percent oxygen, 4 percent carbon dioxide. https://sciencing.com/chemical-composition-exhaled-air-human...
The minimum oxygen concentration in the air required for human breathing is 19.5 percent. ... hen oxygen concentrations drop from 19.5 to 16 percent, and you engage in physical activity, your cells fail to receive the oxygen needed to function correctly. Mental functions become impaired and respiration intermittent at oxygen concentrations that drop from 10 to 14 percent; at these levels with any amount of physical activity, the body becomes exhausted. Humans won't survive with levels at 6 percent or lower. https://sciencing.com/minimum-oxygen-concentration-human-bre...