The diagram below shows how salt is removed from seawater to make it drinkable. Summarise the information by selecting and reporting the main features, and make comparisons where relevant.

The figures illustrate the process of how salt and contaminants are separated from

seawater

and how to make fresh and drinkable

water

.

Overall

,

it is clear that

there are three main stages and it starts with draining

seawater

into the system and ends with distributing clean

water

.

To begin

with,

seawater

will be drained by a pipe into the pre-treatment filter

and

Correct word choice

apply

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in

this

stage, there are two ways

and

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apply

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one of them is to filter backwash back to the sea

while

the other one will pass the salted

water

to the next stage.

Furthermore

, in the second chamber, the sea

water

is forced through

membrane

Correct article usage

a membrane

show examples

by using high pressure which in in turn both impurity substances and salt will be segregated and only pure

water

molecules get through these tiny holes. What is interesting to note is that those residues so-called '

seawater

concentrate' will be combined with the filter backwash from the previous stage and back to the sea.

Additionally

, in the next procedure, the

water

will be cleansed by lime, chlorine and fluoride,

as a result

, the clean and fresh

water

is stored in a gigantic rectangular-shaped storage before integrating a

water

supply system.