Seawater To Fix California’s Drought?

How do we make seawater drinkable? And can that technology save California?!

Hosted by: Michael Aranda

https://www.youtube.com/watch?v=mAvLtBSJK2Y

maybe you’ve heard that California has been having some water trouble lately

and I lately I mean for the past five years

California is experiencing a serious drought and if it continues it could

cause permanent damage to its ecosystems threaten its precious freshwater

resources and ruin the state’s many many crops but maybe you’re thinking how can

a state that shares 1350 kilometers of coastline with an ocean be out of water

well ocean water is full of salt that’s how but it doesn’t have to stay that way

because there’s a process called desalination which removes the salt from

the sea water to make it drinkable it’s already used in some parts of the world

on a large scale so now both scientists and citizens are wondering whether

Desalle as it’s sometimes called can help California out of its drought so

let’s take a look at how desalination currently work there are five different

methods using facilities around the world to extract pure water from

seawater but over eighty percent of the world’s desalinated water is produced by

just two of these methods they are known as reverse osmosis and multistage flash

reverse osmosis eases pressure to remove salt other minerals and microbes from

seawater the water is pumped through a bunch of semi permeable membranes which

contain tiny pores that let water molecules pass through but filter out

other particles if they’re too big or charge the water that gets forced

through the membranes becomes usable freshwater but the leftover water is

just so salty and full of other junk that it’s too expensive to extract any

more fresh water so it sent off to a separate treatment plan this extremely

salt saturated water is known as concentrate or brian a multi-stage flash

seawater is brought to a boil multiple times as it travels to a series of

chambers creating some water vapor and leaving the dissolved salts in a liquid

fresh water is collected as the water vapor Rises the top of these chambers

and condenses the leftover brian is either recycled in other parts of the

system or disposed of some of these technologies have been effectively used

in 30 countries around the world for example the ra’s al khair desalination

plant in Saudi Arabia uses both reverse osmosis and multistage flash processes

it’s capable of pumping out about 1 million cubic meters of desalinated

water every day in Israel meanwhile sorry desalination plant uses reverse

osmosis exclusively and can supply around six hundred and twenty thousand

cubic meters of fresh water per day to the country’s water systems so why don’t

we use this stuff to solve California’s drought problem

well even the biggest desal plants in the world are only supplemental they

don’t make enough water to support an entire population the carlsbad

desalination plant in California for instance is helping produce fresh water

through reverse osmosis but at best it provides less than ten percent of

regional water demand these salivating seawater can also be twice as expensive

as treating other water sources like rain water waste water on a large scale

most of that expense comes from the energy that’s needed to heat the water

or apply pressure to it according to some estimates it takes about

twenty-five thousand US dollars worth of electricity per month to produce enough

Desalle water for only 1,200 homes plus there’s the problem of how to process

all that leftover Brian you can’t just dump it back into the ocean because the

extreme levels of salt have been shown to damage fish coral and sea grass

finally there are logistics to consider most of California’s water is used for

agriculture but the state’s growers will be largely unaffected by any effort to

desalination see what why because most California farms are inland not even

close to the ocean which is generally where you want to put desalination plant

so to help quench California’s thirst

we’re gonna have to try new d cell technologies one promising technique

scientists are developing in California is solar desalination which harnesses

the thermal energy of the Sun to power a desalination plant an example of this

would be a multiple effects distillation plant which is a lot like multistage

flash except the steam from the first stage is used to boil water in the

second stage and the steam from the second stage is used to boil water in

the third stage and so on solar desalination be able to make clean water

at lower cost than conventional detail and it could produce less brine some

companies even estimate around 93% of the salt water being turned into fresh

water for now though the cost and logistical problems of these salivating

seawater just too big to solve problems like the California drought but with

more research and ingenuity desal plants could provide at least some relief to

drought-stricken communities everywhere

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suggested in Western North American could enter a mega droughts in the next

decade held in part by climate but what are mega ground

Seawater To Fix California’s Drought?