Sources, Composition, and Properties of Solid Waste

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Sources, Composition, and Properties of Solid
Waste
Prepared by Ahmed Sawalha
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Presentation Outline

• Sources of Solid Wastes
• Types of Solid Waste
• Composition of Solid Waste
• Determination of the Composition of MSW in the
  Field
• Types of Materials Recovered from MSW
• Future Changes in Waste Composition

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Sources and Types of Solid Wastes

• Sources of solid wastes in a community are
• Residential
• Commercial
• Institutional
• Construction and Demolition
• Municipal Services
• Treatment Plant Sites
• Industrial
• Agricultural

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Sources and Types of Solid Wastes

• MSW includes all the community waste with the
  exception of industrial process waste and
  agriculture wastes
• It is important to define the various types of
  solid wastes that are generated and the sources
  to design and operate of the functional elements
  associated with the management of solid waste

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Sources and Types of Solid Wastes

• Table 1 provides the sources and types of solid
  waste within a community

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Sources and Types of Solid Wastes
Table 1 Sources and Types of Solid Wastes within
a Community
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Sources and Types of Solid Wastes
Table 1 Sources and Types of Solid Wastes within
a Community (Contd)
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Sources and Types of Solid Wastes
Table 1 Sources and Types of Solid Wastes within
a Community (Contd)
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Nature of Municipal Solid Waste

• Organic (Combustible)
• Inorganic (non-combustible)
• Putrescible
• Recyclable
• Hazardous
• Infectious

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Composition of Solid Wastes

• Composition is the term used to describe the
  individual components that make up a solid waste
  stream and their relative distribution
• Information on the composition of solid wastes is
  important in evaluating equipment needs, systems
  and management programme and plans

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Composition of Solid Wastes

• The residential and commercial portion makes up
  about 50 to 75 percent of total MSW generated in
  a community
• The actual percentage distribution will depend
  on
• The extent of construction and demolition
  activities
• The extent of the municipal services provided
• The types of water and wastewater treatment
  process that are used

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Composition of Solid Wastes

• Composition is the term used to describe the
  individual components that make up a solid waste
  stream and their relative distribution
• Information on the composition of solid wastes is
  important in evaluating equipment needs, systems
  and management programme and plans

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Composition of Solid Wastes

• The residential and commercial portion makes up
  about 50 to 75 percent of total MSW generated in
  a community.
• The actual percentage distribution will depend
  on
• The extent of construction and demolition
  activities
• The extent of the municipal services provided
• The types of water and wastewater treatment
  process that are used.

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Typical Physical Composition of Residential MSW
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Composition of Solid Waste

• The percentage distribution values for the
  components in MSW vary with
• Location
• Season
• economic conditions
• population
• Social behavior
• Climate
• Market for waste materials
• Other factor

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Determination of the Composition of MSW in the
Field

• Because the heterogeneous nature of solid wastes,
  determination of the composition is not an easy
  task
• More generalized field procedures based on common
  sense and random sampling technique have evolved
  for determining composition
• The procedure for residential MSW can be
  summarized as following
• The load is first quartered
• One part is then selected for additional
  quartering unit a sample size of about 200 lb is
  obtained
• It is important to maintain the integrity of each
  selected quarter regardless of the odor or
  physical decay
• make sure that all the components are measured

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Determination of the Composition of MSW in the
Field

• The field procedure for component identification
  for commercial and industrial waste involves the
  analysis of representative waste samples taken
  directly from the source, not from a mixed waste
  load in a collection vehicle. Due to the fact
  that these wastes are so variable.

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Types of Materials Recovered from MSW

• Aluminum
• Paper
• Plastics
• Glass
• Ferrous Metals (Iron and Steel)
• Nonferrous waste
• Yard waste collected separately
• Construction and demolition wastes

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Types of Materials Recovered from MSW

• Recycling is the best way to solve solid waste
  management problem. This process exists in all
  cities . However, the recycling system differs
  from developing countries and developed countries
  .
• Developed countries have well organized source
  separation and recycling system while in the
  developing countries the system of recycling is
  not effective because it is still in the hands
  of informal sectores

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Developing Countries Have Recycling System
Starting From Curbside Collection System.
Separate Colored Collections Bins are Provided to
Deposit Separate Waste Material
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These Sorting Facilities are Well Organized and
Materials are Separated for Further Processing
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Separation of Recyclable and Placing Separately
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These Scavengers Collect the Recyclables and
Separate in their Own Premises
T
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Recyclables Collected from Scavengers are
Deposited in One Place
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Future Changes in Waste Composition

• In terms of solid waste management planning,
  knowledge of future trends in the composition of
  solid waste and quantities are of great
  importance.
• Food Waste
• The quantity of residential food waste collected
  has changed significantly over the years as a
  result of technical advances and change in public
  health
• Food processing and packaging industry and the
  use of kitchen food waste grinders have effected
  the quantity of food waste
• The percentage of food waste, by weight, has
  decreased from about 14 percent in the early
  1960s to about 9 percent in 1992.

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Future Changes in Waste Composition

• Paper and Cardboard
• The percentage of paper and cardboard found in
  MSW has increased greatly over the past half
  century , rising from about 20 percent in the
  early 1940s to about 40 percent in 1992
• if the U.S. postal rate for bulk mail were
  increased to first class mail, a significant
  reduction would occur in the amount of paper
  collected for disposal
• Yard Wastes
• The percentage of yard waste has also increased
  significantly, due primarily to passage of laws
  that prohibit burning of yard wastes.
• By weight, yard waste currently accounts for
  about 16 to 24 percent of the waste stream
• Environmental conditions such as droughts have
  also affected the quantities of yard wastes
  collected in certain locations

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Future Changes in Waste Composition

• Plastics
• The percentage of plastics in solid waste has
  increased significantly during the past 50 years
• the use of plastics has increased from almost
  non-measurable quantities in the early 1940s to
  between 7 and 8 percent, by weight, in 1992
• It is anticipated the use of plastic will
  continue to increase, but at a slower rate than
  during the past 25 years