Page 208 - Materials Chemistry, Second Edition

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Municipal Solid Waste Processing; Materials Recovery Facilities 179

FIGURE 7.7 Transfer point along a conveyor belt. Wastes sometimes fall away from the belts during transfer
to another belt.

FIGURE 7.8 Small scale for weighing bales and other small- and medium-sized objects.

mixed feed of x and y is shown in Figure 7.9. The goal of the unit operation is to separate the x
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fraction in as pure a form as possible and with the greatest total recovery possible.
One exit stream will contain the x component, the desired material, also designated the product
or extract. Separation will not be perfect, however, so there will inevitably be contamination as y .
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A second stream, containing mostly the y is known as the reject. Note that this stream will contain
some of the product x. The recovery of x can be expressed as (Hasselriis, 1984)
R(x ) (x /x ) 100 (7.3)
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0
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where R(x ) is the recovery of x in the first output stream (%).
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