2.3 Conventional Approaches for Hazardous Solid Waste Disposal
41
well as methods that result in chemical alteration of a liquid phase to produce
a solid, vapor or altered liquid phase. Examples of chemical treatments include
hydrolysis, catalysis, dissolution, oxidation, reduction, electrolysis, neutralization,
ozonation, etc. Biological treatments are the methods used for biodegradation of
organic wastes such as activated sludge method, aerated lagoon, anaerobic digestion, enzyme treatment, trickling filter and waste stabilization. Thermal treatments
are the methods to vaporize, oxidize or destruct liquid or solid phase components at
elevated temperatures, which include calcination, incineration, molten salt, plasma
destruction, pyrolysis and supercritical fluid oxidation [28].
Recycling programs play an important role in keeping the waste out of landfills
and recovering useful resources from them. Recycling programs for specific types
of hazardous wastes such as electronic wastes (e-wastes) are currently adopted in
many provinces including British Columbia, Alberta, Saskatchewan, Ontario, Nova
Scotia and Prince Edward Island. These programs have diverted more than 172,000
tonnes of e-wastes from landfills since 2004 [4].
Import and export of hazardous waste and hazardous recyclable materials are
regulated under the Canadian Environmental Protection Act 1999 (CEPA 1999).
Canada is a party to the following three international agreements on the transboundary
movements of hazardous waste and their disposal [4, 29]:
– The United Nations Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal.
– The Organization for Economic Co-operation and Development Decision of
Council on the Control of Transfrontier Movements of Wastes Destined for
Recovery Operations.
– The Canada-U.S. Agreement Concerning the Transboundary Movement of
Hazardous Waste.
In 2005, Canada adopted the Export and Import of Hazardous Waste and
Hazardous Recyclable Material Regulations (EIHWHRMR) that regulates international movements of hazardous waste and recyclables out of, into and through Canada
[29]. Figure 2.6 presents the total annual quantity of exported, imported and transited hazardous waste and recyclables in Canada between the years of 2007 and
2016. Most of the waste imported into Canada was from the United States (99.9%)
with a small portion from Jamaica, Nigeria, Norway, Brazil, Australia and Indonesia.
In 2016, more than 380,000 tonnes of hazardous waste was imported into Canada,
including metal-bearing waste, organic solvents, flammable liquids, chemical treated
wood, wastes from production and use of biocides, pesticides, phytopharmaceuticals
and herbicides and wastes from tarry residues of refining, distillation and pyrolytic
treatments. 69% of the imported waste was hazardous recyclable materials such
as spent lead-acid batteries, hydraulic fluids, spent sulfuric acid, corrosive liquids,
waste liquors from pickling of metals, metal-bearing waste and flammable liquids.
The hazardous recyclable wastes imported in 2016 were mainly treated through
the recovery of metals and metal compounds (46%), re-refining or re-use of used oil
(31%) or recovery of a recyclable material (16%) [29]. The hazardous non-recyclable
waste imported was treated mainly by thermal methods such as incineration (38%),
41
well as methods that result in chemical alteration of a liquid phase to produce
a solid, vapor or altered liquid phase. Examples of chemical treatments include
hydrolysis, catalysis, dissolution, oxidation, reduction, electrolysis, neutralization,
ozonation, etc. Biological treatments are the methods used for biodegradation of
organic wastes such as activated sludge method, aerated lagoon, anaerobic digestion, enzyme treatment, trickling filter and waste stabilization. Thermal treatments
are the methods to vaporize, oxidize or destruct liquid or solid phase components at
elevated temperatures, which include calcination, incineration, molten salt, plasma
destruction, pyrolysis and supercritical fluid oxidation [28].
Recycling programs play an important role in keeping the waste out of landfills
and recovering useful resources from them. Recycling programs for specific types
of hazardous wastes such as electronic wastes (e-wastes) are currently adopted in
many provinces including British Columbia, Alberta, Saskatchewan, Ontario, Nova
Scotia and Prince Edward Island. These programs have diverted more than 172,000
tonnes of e-wastes from landfills since 2004 [4].
Import and export of hazardous waste and hazardous recyclable materials are
regulated under the Canadian Environmental Protection Act 1999 (CEPA 1999).
Canada is a party to the following three international agreements on the transboundary
movements of hazardous waste and their disposal [4, 29]:
– The United Nations Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal.
– The Organization for Economic Co-operation and Development Decision of
Council on the Control of Transfrontier Movements of Wastes Destined for
Recovery Operations.
– The Canada-U.S. Agreement Concerning the Transboundary Movement of
Hazardous Waste.
In 2005, Canada adopted the Export and Import of Hazardous Waste and
Hazardous Recyclable Material Regulations (EIHWHRMR) that regulates international movements of hazardous waste and recyclables out of, into and through Canada
[29]. Figure 2.6 presents the total annual quantity of exported, imported and transited hazardous waste and recyclables in Canada between the years of 2007 and
2016. Most of the waste imported into Canada was from the United States (99.9%)
with a small portion from Jamaica, Nigeria, Norway, Brazil, Australia and Indonesia.
In 2016, more than 380,000 tonnes of hazardous waste was imported into Canada,
including metal-bearing waste, organic solvents, flammable liquids, chemical treated
wood, wastes from production and use of biocides, pesticides, phytopharmaceuticals
and herbicides and wastes from tarry residues of refining, distillation and pyrolytic
treatments. 69% of the imported waste was hazardous recyclable materials such
as spent lead-acid batteries, hydraulic fluids, spent sulfuric acid, corrosive liquids,
waste liquors from pickling of metals, metal-bearing waste and flammable liquids.
The hazardous recyclable wastes imported in 2016 were mainly treated through
the recovery of metals and metal compounds (46%), re-refining or re-use of used oil
(31%) or recovery of a recyclable material (16%) [29]. The hazardous non-recyclable
waste imported was treated mainly by thermal methods such as incineration (38%),