1.1 Wastes Generation
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discharges were 6.4 billion tonnes in 2006, and industrial wastewater discharges were
29.9 billion tonnes in 2009 [2].
1.2 Wastes Characterization
Generally, wastes generated from residential, industrial and commercial establishments can be classified into hazardous or non-hazardous wastes. Hazardous wastes
are materials that are potentially dangerous or harmful to human health or the environment. They cannot be treated by the normal waste and recycling approaches
due to their health hazard or environmental harmfulness [2]. Non-hazardous wastes
are typically the curbside household garbage and similar wastes generated by businesses and institutions, e.g., printed paper and packaging (such as plastics, paper,
glass, aluminum and steel), organics from food and yard waste, tires, cement, metals
and glass from construction and demolition [9].
1.2.1 Hazardous Wastes
Hazardous waste may be flammable, corrosive or toxic and they usually need special
pre-treatments before being disposed or recycled [2]. Transportation of Dangerous
Goods Regulations (TDGR) administered by Transport Canada has divided the
hazardous waste into nine classes according to their type of danger, as summarized
as follows [10–12]:
Class 1—Explosives: Explosives are substances that are capable of producing
a large amount of gas (vapor) in a short period of time as a result of chemical
reactions, generating a high pressure or high-speed blast wave that would damage
the surroundings. They can also be explosive or pyrotechnic if exposed to heat, light,
and sound, gas or smoke through self-sustaining exothermic chemical reactions.
Class 2—Gases: This class of hazardous waste includes a gas, or a mixture of
gases with one or more vapors of substances included in other classes. Gases in
this category include flammable gases that are ignitable at ambient conditions in a
mixture of 13 vol. % or less with air, or toxic gases that are known to be toxic or
corrosive to humans, or have a lethal concentration value (LC 50 ) less than or equal
to 5000 mL/m
3 .
Class 3—Flammable liquids: This class includes substances that are liquids or
liquid solutions or suspension containing solids that have a flashpoint less than or
equal to 60 °C or they are intended or expected to be at a temperature greater than
or equal to their flashpoint.
Class 4—Flammable solids: Substances included in this class are liable to spontaneous combustion, or water-reactive substances that emit flammable gases if they
come in contact with water.
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discharges were 6.4 billion tonnes in 2006, and industrial wastewater discharges were
29.9 billion tonnes in 2009 [2].
1.2 Wastes Characterization
Generally, wastes generated from residential, industrial and commercial establishments can be classified into hazardous or non-hazardous wastes. Hazardous wastes
are materials that are potentially dangerous or harmful to human health or the environment. They cannot be treated by the normal waste and recycling approaches
due to their health hazard or environmental harmfulness [2]. Non-hazardous wastes
are typically the curbside household garbage and similar wastes generated by businesses and institutions, e.g., printed paper and packaging (such as plastics, paper,
glass, aluminum and steel), organics from food and yard waste, tires, cement, metals
and glass from construction and demolition [9].
1.2.1 Hazardous Wastes
Hazardous waste may be flammable, corrosive or toxic and they usually need special
pre-treatments before being disposed or recycled [2]. Transportation of Dangerous
Goods Regulations (TDGR) administered by Transport Canada has divided the
hazardous waste into nine classes according to their type of danger, as summarized
as follows [10–12]:
Class 1—Explosives: Explosives are substances that are capable of producing
a large amount of gas (vapor) in a short period of time as a result of chemical
reactions, generating a high pressure or high-speed blast wave that would damage
the surroundings. They can also be explosive or pyrotechnic if exposed to heat, light,
and sound, gas or smoke through self-sustaining exothermic chemical reactions.
Class 2—Gases: This class of hazardous waste includes a gas, or a mixture of
gases with one or more vapors of substances included in other classes. Gases in
this category include flammable gases that are ignitable at ambient conditions in a
mixture of 13 vol. % or less with air, or toxic gases that are known to be toxic or
corrosive to humans, or have a lethal concentration value (LC 50 ) less than or equal
to 5000 mL/m
3 .
Class 3—Flammable liquids: This class includes substances that are liquids or
liquid solutions or suspension containing solids that have a flashpoint less than or
equal to 60 °C or they are intended or expected to be at a temperature greater than
or equal to their flashpoint.
Class 4—Flammable solids: Substances included in this class are liable to spontaneous combustion, or water-reactive substances that emit flammable gases if they
come in contact with water.