How hard is it to convert sea water to drinking water on a large scale basis?

Answer 1

One process that is used to convert sea water to drinking water on a large scale basis is called Desalination. Desalination is a process that removes dissolved minerals (including but not limited to salt) from seawater, brackish water, or treated wastewater. A number of technologies have been developed for desalination, including reverse osmosis (RO), distillation, electrodialysis, and vacuum freezing. Two of these technologies, RO and distillation, are used extensively by municipalities and private companies.

Reverse Osmosis is a treatment process whereby the dissolved minerals may be separated from water by forcing the water through a semi-permeable membrane under high pressure. The water diffuses through the membrane and the dissolved salts remain behind on the surface of the membrane.It requires a lot of energy and is fairly expensive.

In the distillation process, feedwater is heated and then evaporated to separate out dissolved minerals.

In coastal ares that are arrid or do not have surface water readily available, desalination are sometimes employed. Of the more than 7,500 desalination plants in operation worldwide, 60% are located in the Middle East. The world's largest plant in Saudi Arabia produces 128 MGD of desalted water.

However, the operation costs and maintenance of these plants are costly and require a lot of energy although RO plants are generally less expensive as compared to distillation plants.

Answer 2

The objective is to separate the pure water from brine with the use of the minimum energy.
Sea water is, of course, the source of the brine.

A large cylindrical distillation vessel receives the brine at a pressure below that of the atmosphere... about 25"Hg.vacuum.

This is achieved by using steam ejector sets and barometric ejector condensers to 'pull' out air and any other uncondensible gases from the vessel together with the produced steam from the brine.

The brine is pre-heated (see below) and passes into and through the vessel receiving more heat from superheated steam passing through heating coils immersed in the brine.
Due to the low pressure, the water boils, producing steam at around 66 °C (150°F).
This steam is also pulled out by the ejector sets and condensers (brine pre-heaters), and, when condensed to pure water in exchangers (also pre-heating the brine), then further cooled to ambient temperature, it passes to storage tanks for distribution to its users. The uncondensed gases are released to atmosphere via a system of barometric loops and check valves.
Some of the produced water goes as boiler feed water to produce the steam that produces the water.

The brine leaving the distillation vessel, now at an increased salt concentration, is returned to the sea... away from the area that the sea water is taken from.

One other point, the process is very simple and not too costly after the initial cost of building the plant and ancillary equipment.
The manpower (small number), running and maintainance costs are of course required.

Answer 3

I heard of this method of pumping the sea water to a spray hose in an area that is well below freezing. The "snow" that accumulates somehow separates the water from the salts and minerals. I don't know if it's true or not, but I remember seeing it on the news about 15 years ago.

Answer 4

for a higher deliver that has more beneficial than shall we are saying fifty human beings, it would not be plausible without an power source that can provide adequate to warmth up the water and then evaporate it, once you've this kind of power you may be able to get the boat transferring besides. yet sure you may nicely be sustainable if it replaced right into a small relatives(3 or 4 human beings), this can be boat had bins that the position darkish, plastic wrap, and some thing to carry the water at the same time as it condenses, and a sturdy volume of photograph voltaic.

Answer 5

It is very expensive because it requires a great deal of energy input. It is not very practical in the sense that it costs more money (at least at this time) to make than the end product of drinking water is currently worth. A professor once told our class that if one of us invented an inexpensive electrolysis reaction, that person would become the world's richest person. I'm not sure if that is true, but you get the idea.

Answer 6

i think if you wanna make drinking water from sea water all you do is take a bowl and put the sea water in it....get a plastic piece to put over it and put the bowl of sea water in a bigger bowl put it in the sun and the water will evaporate and hit the plastic and run down into the big bowl and the salt and water will be separted...i hope thats what ur asking cuz im not sure... but if so i hope it helps

Answer 7

Not as difficult as it is expensive. The fact that it's not cost effective is the reason that it's not done on a large scale.

Answer 8

it's hard. takes lots of energy

Answer 9

not too hard technically speaking