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The latest project is to take a city of around half a
million inhabitants and discovers exactly what raw materials 【S1】______
go into it and what go out.The aim is to find out how much
of these raw materials could be provided whether a plant for 【S2】______
recycling waste were built just outside the city.This plant would
recycle not only metal such as steel，lead but copper，but also 【S3】______
paper and rubber as well as.【S4】______
Another new project is being set off to discover the best 【S5】______
ways of sorting and separating the rubbish.When this project
is complete，the rubbish will be processing like this：first，it will 【S6】______
pass through sharp metal bars which will tear open the plastic
bags on which rubbish is usually packed；then it will pass through 【S7】______
a powerful fan separate the lightest elements from the heavy 【S8】______
solids；after that grounders and rollers break up everything what 【S9】______
can be broken.Finally the rubbish will pass under magnets，
which will remove the bits of iron and steel；the rubber and
plastic will then sorted out in the final stage.【S10】______
The first full scale giant recycling plants are，perhaps，fifteen
years away.Indeed，with the growing cost of transporting rubbish
to more distance dumps，some big cities will be forced to build
their own recycling plants before long.