This document discusses various material separation and processing techniques used in waste management. It begins with an introduction to waste separation and its purposes. It then outlines different separation processes like picking, screening, magnetic separation, air classification, optical separation, eddy current methods, and flotation. Each process is described in detail with examples. The document also discusses how separated materials like plastics, paper, glass, and metals can be further processed and recycled. It concludes that the appropriate separation and processing techniques depend on the type of waste and intended use of recovered materials.

1. M A T E R I A L
S E P A R A T I O N A N D
P R O C E S S I N G
T E C H N I Q U E S I N
W A S T E
M A N A G E M E N T
P R E S E N T E D B Y: K A N Z A S A L E E M

2. INTRODUCTION
Waste separation is the process by which waste is separated into
different elements.
Separation is used to permit more efficient processing of waste
components.
And can be separated in
 Material recovery facilities
 Mechanical biological treatment system
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3. TYPES OF SEPARATION PROCESSES
Picking
Screening
Magnetic separation
Air classification
Optical separation
Eddy's current method
Flotation
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4. PICKING
Most positive way to achieve the recovery and reuse of
materials.
Manual separation of solid waste can be accomplished at
source where
 Solid waste are generated
 Transfer station
 Centralized processing station
 Disposal site
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5. Manual sorting rates and efficiencies
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6. SCREENING
Screens are used for achieving efficient separation of
particles through dependence on differences between particle
sizes with respect to any two dimensions.
Screening process can be use for oversized feed stocks as
well as for undersized feed stock.
Types of screening process
a) Tromel screening
b) Disc screening
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7. • The Tromel screen is perforated rotating drum.
• Set at an angle to allow for gravity feed and discharge.
• Efficient for processing mixed waste and other mixtures where large, flat
particles (e.g., paper) and aggregate-type particles (e.g., crushed glass)
must be separated.
TROMEL SCREENING
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8. DISC SCREENING
• Disc screens have been employed in many waste processing facilities.
• A disc screen consists of a number of evenly spaced shafts in a
horizontal plane fitted with discs such that their interference patterns
form openings through which the undersize material will flow. All of the
shafts rotate in the same direction, thus carrying infeed material from
one end of the screen to the other.
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9. MAGNETIC SEPARATION
Magnetic separation is a process used to segregate magnetic (i.e.,
ferrous) metal from a mixture of different types of materials, e.g., mixed
waste or commingled metal, glass, and plastic containers.
The process is technically simple and of relatively low cost.
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10. AIR CLASSIFICATION
Process of separating categories of materials by way of differences in
their respective aerodynamic characteristics.
(aerodynamic characteristic of a particular material is primarily a function of the
size, geometry, and density of the particles.)
Horizontal air classifier vertical air classifier
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11. Typical operating and performance characteristics of air
classifiers used for recovery
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12. EDDY CURRENT SEPARATOR
Eddy current separator uses a powerful magnetic field to separate non-
ferrous metals from waste.
Eddy current separators are not designed to sort ferrous metals which
become hot inside the eddy current field.
 Consists of a
 short belt conveyor
 high speed magnetic rotor system
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13. OPTICAL SORTERS
Optical sorting machines are the incorporation of optical sensors along
with mechanical separators.
Small, powerful air jets blow targeted materials off of a conveyor belt.
Optical sorters distinguish color differences based on visible light but
also distinguish different materials,
like plastics, resins, glass.
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14. FLOTATION SYSTEM
• It separate hydrophobic particulates from hydrophilic particulates by
passing fine air bubbles up through a solid- liquid mixture.
• The fine bubbles attach to and lift or float the hydrophobic particles up
where they are collected.
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15. PROCESSING OF WASTE
Processing techniques are used in solid waste management systems
To improve the efficiency of solid-Waste disposal systems
To recover Resources
To prepare materials for the recovery of conversion products and
energy
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16. Plastics including PET bottles ,food trays etc. can be recycled through
following process.
Receiving
yard
Bale
opener
Colour
bottles
separatio
n
Labels/ca
p
separation
Coarse
crushing
Fine
crushin
g
washer
dehydrator
PET
flakes
PLASTIC PROCESSING
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17. Plastic processing
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18. PAPER PROCESSING
Separated papers through different separation
techniques is collected in large container.
Paper is taken to recycling plant ,separated
according to types and grades.
Washed with soapy water to remove ink, plastic
film, glue.
Then mixed with in a container to make slurry
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19. By adding different materials to the slurry, different
paper products can be created, such as cardboard,
newsprints or office paper.
The slurry is spread using large rollers into large
thin sheets.
The paper is left to dry, and then it is rolled up
ready to be cut and sent back to the shops.
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20. GLASS PROCESSING
Sorting
Producing glass cullet
Removing contaminants
Making recycled glass
Decolorizing and dying
Making recycled glass product
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21. METAL PROCESSING
 Collection
from drop-off points and metal recycling centers
 Sorting
into categories for recycling, such as ferrous and non-ferrous metals.
 Compaction
to allow for more efficient recycling
 Shredding
to separate the parts into small, manageable pieces
 Melting
to reduce the metals to their base state
 Purification
using processes such as electrolysis
 Molding
into sheets and ingots
 Shipping
to manufacturers for reuse 21Department of Environmental Scieces, QAU Islamabad

22. CONCLUSION
Waste separation processes depend upon:
 Nature of waste
 Efficiency of the process
 Finances
 Time
Waste processing technique depend upon the intended use of waste
material.
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23. REFERENCES
• https://www.dep.state.fl.us/waste/quick_topics/publications/shw/recycling/InnovativeGr
ants/IGYear9/finalreport/Pinellas_IG8-06_Technology_Review.pdf
• www.unep.org/ietc/Portals/.../Waste%20Management/ISWMPlan_Vol1.pdf
• http://wastersblog.com/604/waste-separation-methods/
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