How Desalination Works

new little Uh. It makes you LOGI makes me logi? What's logi? Josh? Just mimic being tired? Okay, A right, I've never heard that. Is that a real word logi? Or is it some Internet short for something much older than that? Okay, keep hello? And what I don't know something? Uh, it's something g I. That's first of balls you're thinking of? Yeah, I don't know what any of the little internet shorthand is. I always have to look that stuff up when someone

leaves a comment. Um, have you heard of first of balls? Instead of first of all? It's now first of bulls? What just by leading us in? It's like first of all, blah blah blah. First of balls, what Yeah, that's just stupid. Now I'm at more of the acronyms like fomo and oh yeah, I have to I never know what those are. We're getting aged. We think first of alls is stupid. We have to look at acronyms. I look up fomo if you're missing out by the way, Oh, is that

what that is? Yeah? I had to look up that. When I was watching Broad City. One of them said that, and I was like, what's fomo? I gotta I gotta keep the old internet handy when I watch those young kids shows. That shows pretty funny. Yeah, it's one. It's my favorite comment the out right. Now. I think I'm really really enjoy it. I just posted today, in fact, on our Facebook page, a great to New Yorker article on Abbey and Allana. Nice because you know how that

the New Yorker does it, They do it great in depth. Yeah, you know, you feel like I never have to read another article again about the ladies of Broad City. When the New Yorker does it, it stays done. That's I think their masked head, is it. Yeah, the New Yorker, when we do it, it stays done. I've read at New Yorker article from that was still awesome about this band called the Shags. It was a super Orleans article

at the Orchid thiefure Um. But it was about this this family band, a girl band called the Shags from the sixties. I've heard of them who, like I, didn't really learn to play their instruments, even though they practice all the time. Yep, you're going to be a band. He tried to take him to the top as much as he could, even right. Yeah, yeah, I remember reading it. That might have been the same article, but are super interesting. Our friend Van nostri And sent us the record. Oh okay,

maybe that's what got me looking into it. The only problem is that he burned it on CD and like, like, our computers don't have CD players mine? Does it home? Good? Yeah? Well I need you to put it on the cloud. You just come over listen to the Shags of the Shags party. Wait, we're talking about illegal activities. We need to buy the Shag album. I don't think it's still in print. Okay, Chuck, Yes, are you familiar with seawater? Yes? Uh, you know there's tons of it out there in the world.

That's right. As a matter of fact, chuckers. Seven point five percent of all the water and earth, and that's seventy of the Earth's surface area is water, right, Yeah, seven point five percent of that is saltwater sea water, which is great. It's good for sailing on, its good for swimming in, it's good for catching um porpoises in doing all sorts of cool stuff, right porpoise fishing expedition. Right. Um. The problem is it is terrible, horrible, unbearable for drinking.

The reason why is because when you drink salt water, it messes with your body's homeostasis. Does this because salt is an electro light, just like they talk about in Um, what's that Mike Judge movie that I love that you don't like? Oh idiocricy idiocracy. Yeah, remember they water the crops with gatoring because it has electro lights. I do not like it. I love that movie. It's a medium

for me. Okay. Um, When you have too many electrolytes or salts, for example, in your body, your body says, hey, cells, you've got a bunch of water, We've got too much salt outside of you. We need you to release some of your water to return the body to homeostasis. Well, if you have too much salt, yourselves purge themselves with too much water in order to excrete the salt out

of your body through urine. Right. Um. And once you do that, you dehydrate your kiddie's malfunction, your brain starts to go downhill, you get brain damage, and you ultimately die a terrible, horrible death from electrolyton balance. Yeah, and that's why when, um, if you were ever lost at sea, let's hope that never happens to anyone. But um, they you do not drink the salt water. It would be

very tempting because it's right there. Um, But they're not kidding when they say water water everywhere, and not a drop to drink. Yeah, I mean you will. You will die a quicker death if you start drinking that salt water. In fact, this has been like a problem for a very long time. Humans have lived in coastal areas for a long, long long time, even before civilization, long long long time. Yeah, so as far because I believe the Greeks in the second century BC wrote down ways of

getting fresh water from saltwater because it's still water. Sure, you just have to figure out how to get the salt out of the water. And one of the best ways, one of the earliest ways, and one of the ways. It's still in use, although in much more high tech use is called solar still. Yeah, I guess a little bit more on the history Aristotle, Uh three BC, it was like, hey, we should desalinate water. So that's the zero two hundred, that'd be the fourth century BC. Okay,

I was wrong. Uh. Plenty the elder, which we by the way, is there a younger? We just got some beer, some plenty the elder. Yeah, thank you Dan, It was Dan, Dan, dude, very much appreciated. I just can't get that stuff here. No, it's an extraordinarily rare beer. Uh dancing of some plenty the elder, So thanks for that. But plenty the elder in Rome Uh also described seawater distillation, and in seventy

a d Alexander of Afrodysseus also did so. About a hundred and thirty years later, and then there was a French explorer named gen de Lrie. Who um did you like that? Who Um? In Fifi talked about desalination. James Cook as well, so it's not a new thing. For many years, humans have been able to look around and say, you want water, There's plenty of it. Let's just figure out a way to to make it not salty. Water

water everywhere, and let's all have a drink. Yeah, which got me um thinking sort of later in the research, like why is the ocean salty to begin with? And I didn't really know until I looked it up. That was a good question. Yeah. It turns out that salt from the ocean comes from rocks here on Earth. It's not just out there in the ocean it Um. What happens is it rains and then uh, it falls on the land and it contains carbon dioxide from the air, and that makes the rain slightly acidic. So when it

hits the rocks, it's gonna break down that rock. Some creating ions, which we've talked about chemical particles that are charged, Yeah, because they're missing an electron, that's right. Uh. And these ions are basically just carried into streams, which eventually into rivers and eventually into oceans, and along the way, a lot of them are used up by organisms. Um, but the ones that are not used up are left over. And of all these ions are sodium and chloride. So boom,

there you have it. Put those two together, you've got salt. Yep, and all that stuff flows in the ocean. And that's why you have got a couple of stats. The three point five percent of the weight of seawater comes from dissolved salts. And they say, some say that if you took all the salt from the ocean and spread it evenly over the Earth's land, just the land, it would be about a forty stories high five feet thick. Wow, there's a lot of salt to get rid of you

and it's all from broken down rocks. Huh. Yeah. And why is desalination a big deal? Because? Uh, clean potable drinking water is a problem in a lot of parts of the world. Dude, it is getting to be a problem faster and faster. Yeah. Like some people say that the future wars will be fought over water, which is

really scary to think about, you know. Um, and for drought to like, uh, it's not just you know, I'm in a developing country and we don't have access to clean drinking water, big problem, But places like California suffer a drought, Like maybe we should think about building desalination plants, right, and they have as a result. Yeah, which we'll get to. So so first of all, we should say happy World Water Day to everybody. It's March two is World Water Day.

So just think about that while you're you know it's March um. And yes, so there's a there's a great need for water. That's the whole reason for World Water Day is to point that out. Supposedly right now, seven million people, um, black access to water. They don't have. There's a water scarcity clean drinking water, yes, um. And they think that that's gonna rise to one point eight billion by in ten years. It's gonna add another one point one billion people to those who face water shortages. Yeah.

We talked about that a little bit in our Life Straw podcasts from quite a few years ago. But the life straw is a um it's about to say single use, not single use, but single serving, single well, not single serving. It's uh what do you call it? If like it's just for one person or a family, uh, single person? Personal? Yeah, heirloom. It's a personal uh device that you can use to literally drink water like out of a river through this straw.

You just put it in the river. It's got filters in it, so it filters out I don't it doesn't filter out salid and it has to be used for fresh water, but it filters out like bacteria, things that you know, disease causing stuff. Um. So, yeah, we did talk about water scarce today. I think we've talked about it in another one too, like why can't we manufacture water and things like that. It's part of our water sweet it is, and it's ongoing because the problem is

not getting better, it's getting worse. One of one of the responses to water shortages around the world is what's called virtual water exporting, which is where you and I have a bunch of fresh water and we use it to grow grain, and then we send that grain to a place that doesn't have much water, so they get to use their water for drinking. They don't have to use it for grain. That makes so and there's a lot of different things that we use water for that

can be exported. It's hard to explore water, but you can use it for stuff and save other people from having to use it. Right. Um, because we use a lot of water. We do use a lot of water, Americans especially, but you hear stats like, oh, this desalination plant can pump out like fifteen billion gallons of fresh water. You think, man, fifteen billion gallons is so much. It's not very much at all. No, it's not a scheme.

I think fifteen billion goallons of water is two thirds of a percent, two thirds of one percent of the amount of water used by humans every day. Yeah, and um, I think all of the desalination plants online, there's seventeen thousand of them. Yeah, and that accounts. I think that's all of them, from the from the very small ones to the ones that are also used in like uh as part of the fracking process. So it's not necessarily all of those are to deliver water to humans. But yeah,

there are that many. So the seventeen thousand desalination plants online in the world, and they think that could double by um, which is pretty good. That's those seventeen thousand of producing twenty one billion gallons a day. I remember, fifteen billion is two thirds of one percent of all of the fresh water used every day around the world. So it's still sorry for the pun, but a drop in the bucket. Yeah, but things are changing fast. They are this new one in California, which we're going to

talk about later. UM is the largest in the Western Hemisphere. Will produce fifty million gallons per day on its own. It's pretty substantial, pretty substantial. UM. So we'll talk about the technology used in this. It's actually kind of old. It needs a little updating, right for this, So, Chuck, there's basically two ways that humans desalinate sea water. Yeah and UM. They've both been around for many, many decades. They're in theory. They're pretty good at removing sea salt

from seawater to create fresh water. But there's over the course of these decades we've found this could be improved, This could be improved. That can be improved, and we'll talk about that later. But this technology, it's been around for a little while, is what I'm trying to say. UM and the two different The main competitors are UM, multi stage flash UH desalination. Yeah. Sometimes I've talked like

Barack Obama, Well that's a good thing. I'm not getting political, Dge mean, he's known as a great orator, was Chuck was uh? And and the other one is reverse osmosis. Do you remember like that poster in in elementary school it was like Garfield laying down on a pile of books taking a nap, and it said, I'm learning through osmosis. I think I do remember that. I was the Garfield

fan think that every time I see the word osmosis. Yeah, I didn't get the joke when I was a kid, and now that I do get, it's not that funny, but I'm reminded of it every time. Yeah, he didn't understand why it Lasagna right. Yeah, it's kind of weird to think about now. And the so the reverse osmosis one is the state of the art. That's the one that's used most widely. Yes, and uh, I think that term was coined in the nineteen fifties by the U. S. Military.

I think we're the first ones to start using that process. Yeah, World War two makes sense. It was an Eisenhoward creation probably. Yeah, Like, we're out on this eye in the Pacific. Our soldiers need some stuff, so let's start a process to um buy stuff, I mean water. We'll start a process where we can take the salt out of the water all around us. And so they did reverse osmosis. Yeah, and and again, I mean we talked about solar stills right, Yeah, I don't think we described like. You can do this

experiment yourself and your at your house. Well. And also, if you're ever caught without without water, you're stranded at sea. Yea, all you need is a bowl and a glass rap and you're fine. Yeah, I mean you can use other things, like if you were Tom Hanks and castaway, you could just try and use the things around you to create the same effect. But yes, go ahead and describe it. Well, you take you take some seawater, you put it in a bowl. You put an empty glass in the middle

of that water. Um, I guess you want to make sure it doesn't float. Other than that, you're fine. Put some stine wrap over it. Poke a hole in the middle of the surrand wrap so that it's over the center of the empty glass, and just set it out in the sun. Yeah, because the sun will cause the water to evaporate, which means it will go up to the underside of the suran wrap, cling to it and condensate into the glass. Oh yeah, into the glass, right,

And what goes into the glass will be freshwater. The salt will be left behind because the evaporation will have separated the two. Yeah, and we're basically described describing you know, rain, right, the rain cycle, but in a glass of suran wrap exactly. And by seran wrap we mean like cellophane wrap. Um. But that's a solar still, that's pretty basic. You can do it on a rowboat again, if you have a glass of bowling suran wrap. Um. Reverse osmosis is something different,

that's right. It's actually the opposite of natural. Quite literally, yes, because osmoses is natural. Reverse osmoses ain't natural. It ain't natural. That is when you put salt water on one side of the membrane, semiprobreable membrane and he use pressure to the tune of I think this one in California is like they said, six times as powerful as a fire hose. Whoa so serious pressure to um to move the water molecules through that membrane basically, and it's it's like a

big filter filters out the salt. Yeah, it's it's calling it anything else, but a filter is kind of fancy. Yeah, because I think they said the pores on these membranes are like smaller than a human hair. So it's not

like your average filtering, you know what I mean. No, it's not The point is what you're doing is you're you're pushing water through membrane that the water can make it through, but the salute, the salt inside of it can't, so the salt is left behind, right and um in a reverse osmosis system, and they call it reverse osmosis because under normal osmosis, what you have is something with a low concentration of a slute, So fresh water water on one side of a membrane and saltwater on the

other side of the membrane. That water is going to the freshwater is going to move from the area of low concentration, so the freshwater is going to move to an area of higher concentration the saltwater in order to achieve one of our favorite things, homeostasis, it wants to achieve a balance so that the stuff on either side of the membrane will be equally salty. Right that that

makes sense, Okay? Reverse ASBOs is the opposite. So if water naturally wants to go from low concentration too high, with reverse osmosis, you're going from high concentration to low. And that's just again another way of putting it, of saying you're filtering the salt from the water by pushing the water through a membrane with a lot of pressure via a lot of pumps. Yeah, and you're running it through a lot more than just one membrane. Oh sure, yeah, yeah, great.

So that's reverse osmosis number one. Uh and not number one in ranking, just it's number one in my book. It see, I'm a multi stage flash guy, are you sure? Why not? Uh? That uses heat. If you've heard of flashing, like flash buying or something, basically means to do something cooking wise very quickly. Um. So flashing in this case is bringing water to a boil really quickly, and multi stage means you're gonna do it in different stages multiple times.

So the name makes sense. Yeah. So basically what you're doing is you're gonna boil this water super fast many times. And each time this happens, water vapor is going to form, and uh, you're gonna have fresh water there and then the salty brine is left over to be disposed of. It's like making a solar still, like a flash boiled solar still over and over again. That's right. So yeah, multi flash, multi stage flash is like um, a super hot solar still over and over again, and each time

you collect that evaporated fresh water behind. There's some real issues with both of these right, as simple as they are. Um And one of the chief ones is that if you take a bunch of saltwater, right and you either filter the freshwater out of it or you boil the fresh water out of it, there's still something left, and that is salt, and you're probably not gonna get all the water. So what you have is called brine. And if you compare brine to seawater, brian is even saltier

than seawater. The reason why is there's not more salt than there's in seawater. There's just less water. So it's like an ultra concentrated form of seawater. Well, you're not gonna do anything with this except try to put it back in the ocean. Once you do that, you have a big, big problem because you kill a lot of the sea life. Yeah. It basically it's heavier, so it settles down on the bottom. And um So the things that they're trying now to combat that is uh one, uh,

diluting it with a bunch of other water. Yeah, I think of five to one ratio is what they are suggesting at this point. And they're not saying like, well, we'll just use some of the fresh water we just distilled out. That wouldn't make any sense. They're using things like UM industrial or agricultural waste water that they were just gonna pump into the ocean anyway, exactly, So mix it with that brine diluted out and it's not going to be as bad for the environment. Uh. They're also

doing it gradually now, much much slower, which also helps. Uh. They're strategically placing it in the ocean in places where it is more UM apt to disperse very quickly. It's a very strategic placement. I think in Australia they try to do uh, they try to re release it to the tune of UM a hundred and sixty two fifty ft away, you won't tell any difference in the are

uh salt concentrations. And then the last thing that they're trying to enforce whenever we build these new plants is UM to bury these pipes and actually do it under the sea floor. Uh. Out of yeah, well, I mean out of side. In other words, is not being released directly into the water. It's being released into the sand under the water, and then I think the sand actually acts as it filter as it disperses. But that's a lot more expense as well to bury these pipes, um,

so chuck. Dealing with Brian is just one challenge that desalination engineers have to deal with the plenty of other ones that popped up over time and come up with some pretty cool solutions or ideas for solving some of these problems. We're gonna get into that right after this, so chuck. Um. When you put seawater through reverse osmosis or multi stage flash, you end up with Brian and you have to figure out what to do with that Brian.

There's some other problems too with desalination. For one, it's expensive. Um. Apparently they measure water on the scale of things like desalination plants and something called um what foot acre, and a foot acre is like three thousand gallons, and a foot acre is about the amount of water at a two American households of five people using a year UM too to deliver desalinated water. At least for the major plant that they're building at Carlsbad, California, UM, it's gonna

be about two thousand dollars per foot acre. Yeah, and we've seen ranges and other articles from other plants um averaging eight hundred to fourteen hundred. This one's a little bit on the high side. But what they're doing is selling it back to the UH city at a rate of two thousand, fourteen to two thousand, two hundred and fifty seven dollars per foot acre, depending on how much they're buying at a time. So basically that's how they

paid for this thing in California. Because they're super expensive to build these plants. They got a thirty year contract agreeing to buy at least forty eight thousand acres acre feet per year, so bonds on that and now they can open their plant. But the problem is, and the reason a lot of people are upset about this is they're like, it's gonna start costing more and more, and like, what happens then, I don't know, I guess people pay more for water. Well, people are definitely gonna be paying

more for water. That's been a really criticism for a very long time of water in America is that it's um artificially cheap. It's should be way more expensive than it is because there you know, there's plenty of places that have lots of water, but there's also plenty of places that are facing drought. UM and the fact that it's so cheap, people tend to abuse it, don't conserve it as much in places where it's very cheap and inexpensive.

So just by increasing the price, there's the school of thought that UM conservation will kick in just because economics kicks in a little more. Yeah, there's some price comparisons here. UM. With this new one in California, the two thousand a foot acre or an acre foot I think we had

that backwards is double that of we had acre. UM. It's double that of water obtained if you built a new reservoir to recycle waste water, and it is four times as much as obtaining what they call new water from conservation methods, so water efficient toilets rebates UM paying for farmers to install like drip irrigation. UH, and that's conservation four times UM four times is expensive. It's four four times more expensive than that than the conservation efforts

they want to try and push through. One of the reasons it's so expensive is because, especially with reverse osmosis. You said that they were using pressure that that exceeded fire hose pressures right six times. Yeah, Okay, that takes a lot of energy because you start out with intake pipes, which again present their own problems because they suck in lots of sea life. So there's a there's an immedia in um deleterious effect on the sea life by sucking

in seawater. Right. Um, So you're sucking in the seawater under high pressure. You're pumping it through sand and charcoal pre treatment. You're pumping it through these membranes, series of you know, usually more than a thousand membranes over a very long distance uh into this treatment plant where it's

further treated. All this requires a tremendous amount of energy, right and when you are when you're desalinating seawater, in particular, films back tend to build up on these membranes, which means you're pumps have to work harder, which means more energy is required to pump that water through, which means the costs rise, the environmental impact prices because it's getting energy probably from a coal fire power plant. So you have this new huge desalination plant that's that wasn't there

before that's increasing your carbon dioxide emissions. So there's a there's a cost to there's an economic cost. There's also an environmental cost with reverse osmosives plants as they exist right now. Yeah, I've got a stat on the energy required this one in Carl's Bad, California, which is just north of San Diego. It uses thirty eight megawatts of energy per day and that is enough to power homes a day a day that wasn't there before. Yeah, it

hasn't gone online yet. When it doesn't two sixteen, it'll be like adding how many five hundred homes worth of energy per day? Yeah, and that's um. I mean, it's great to try and provide because California is doing it specifically for their drought issues. But as we said, even at fifty million gallons a day, it's just a fraction of the problem. And people are there's a lot of people critics saying we don't need to be putting our money in these things. They have examples of m ones

that were built. There was one in Santa Barbara that was built in that cost thirty four million to build and after they started it started raining again. Basically they shut it down Australia had spent ten billion on six of these because of their drought in the nineties and two thousand's and four of those are shut down now because it started rain again. And basically they're like, it's not it's costing way too much money to make this water now, we don't need it. Right, Well, it's the

same thing as like solar power wind power. When oil gets really expensive, then the investment in that seems smarter because the comparatively speaking, the output of solar power windpower isn't as expensive as that expensive oil, right And when the price of oil drops that that solar power output seems really really expensive comparison, and so investment goes away

from it. But what you don't want to have happened, and what they're worried about in California is they're going to build several of these at the cost of like a billion apiece, and they get a lot of rain in five years and then all of a sudden these things are just sitting there. Yeah, So I get the impression. I think it actually says in this San Jose Mercury article you sent um that this Carl's Bad desalination plant outside of San Diego is going to basically be the

litmus test for the rest of the state. Yeah, it's a really big deal. So, like either California will say, yes, desalination works and let's start investing in this, or they're gonna say, no, this doesn't work. It has too much of an environmental cost, the water is too expensive. It just isn't what we need to do. We have to figure out some other stuff. Uh, And it's all coming down to this one plant in two thousand and sixteen

pretty much. But there's been other success stories throughout the world, like UM has a lot of them. Yeah, Saudi Arabia as a leader in desalination, so too is Israel. UM Australia knows what they're doing. Aruba had at the time it opened the largest um productive desalination plant in the world.

So there's a lot of desalination going on. So even if California decides to abandon it, there still needs to be an investment in making these things more energy efficient or environmentally friendly or coming up with new kinds of desalination technology altogether. But whether or not California goes forward with it, that's right at all. Hinges on the Poseidon I think it's what they're calling it, what the plant right for California. But I'm saying, even if that doesn't happen,

other plants around the world demand that they're there. We need to make this better. Yeah, absolutely, Yeah, because people need water, so let's figure out a way to get it cheaply and with small environmental impact. Okay, that's right,

wasn't there. I think a lot of efforts are being made to too, um invest in ones like it's sort of like the LifeStraw, but not like a gravity fed, family sized desalinator, umstead of these really expensive ones a huge desalination plant, or do you need like a bunch of smaller portable desalination units? Yeah, like a unit that will take care of a village, let's say, in a developing country. Why not. It's pretty interesting, it is for some and water has always struck me. It's very interesting.

Every time we do an episode like this, I'm like, man, this stuff gets me. It's a commodity that is becoming more scarce, which is scary to think about because it's such a basic thing that every human needs. Yeah, it's not like well, I mean, things would go bad if we ran out of oil too, but it's not like water. Yeah, I mean like society would collapse and civilization with not everyone's gonna die directly. Yeah, from a lack of oil.

Will die from murder right over the lack of oil. Uh. If you want to know more about water, just type that magic word into the search bar how stuff works, and it will bring up a just a plethora of really interesting articles. And I said search part in there. So it's time for a listener man. Yeah, I'm gonna call this brave, brave email from a young person about depression. It's really neat. Hey, guys, my name is Brooke and I'm from Beer Area, Kentucky. Absolutely love your show. I

think you're both extremely and intelligent and inspiring. I don't know about that. I've learned a lot about various topics while listening to your show and can't get enough. I wanted to email you, guys, because I wanted to get a message out to as many people as I can. I am fifteen years old, have been hospitalized three times for depression. The last time was because I attempted suicide

by overdosing on trisdone. I was aware but hyperventilating when my mother found me on the bathroom floor, called nine one one and an ambulance took me to the local hospital. UH and then I was sent to a facility after recuperation for depression for a little over a week and did not get just charged until Christmas Eve. The day I attempted suicide was the day I turned my life around. Though since then I've been doing amazing and have come to the realization that harming myself was not the way

to go. UH. So I wanted to tell anyone and everyone that suffers from this kind of depression to know that there is hope, and I wanted to start publicly speaking about experiences so hopefully try and motivate others so you have the same epiphany I did. I would really appreciate it if you guys read this on the air during the podcast. Thank you from Brooke. So Brooke, that

is a very brave thing to do. Yeah, thanks Brooke as a fifteen year old, and really for any age to be so forthcoming about your struggle and uh to try and help people out. So thanks for that. Yeah, thank you. Um if you want to send us a letter and email, you want to say hi, you want to share your story, anything, like that, especially if you think it will help other people. You can tweet to us. If it's a really short story at s y ESK podcast. You can post it on Facebook dot com, slash stuff

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