40
2 Conventional Approaches for Waste Management …
Thermal treatment facilities are usually equipped with air pollution control (APC)
systems designed based on the waste feed composition, the thermal treatment technology and the specific emission limits applicable to the facility. The typical elements
and operating procedure of an APC syste are as follows [19]:
– Dioxins and furans are destructed by thermal treatment at high temperatures
(1000–1200 °C) and are captured by baghouse filter and activated carbon and/or
catalytic reactor adsorption
– Heavy metals are captured by baghouse filter and activated carbon and/or catalytic
reactor adsorption
– Particulates are captured through baghouse filter and/or electrostatic precipitator.
– A scrubbing section neutralizes acid gases (HCl, SO 2 ) through lime injection
The Canadian Council of Ministers of the Environment (CCME) has issued guidelines for the operation of municipal waste incinerators depending on the size of the
system. According to these regulations, units with more than 9.6 tonnes per day
capacity are required to follow strict emission standards and need to install a complete
APC system. The emission standards require periodic monitoring of the stack gas for
air pollutants concentration. Less strict emission standards (specific to each province)
apply to the units with lower capacities and they can only install a simple scrubber
system. In these systems cooled flue gas passes through an acid scrubber to reduce
or remove the acid gases (HCl, SO 2 ), while particulates and other contaminants can
be controlled inside the incinerator [19].
2.3 Conventional Approaches for Hazardous Solid Waste
Disposal
Hazardous waste is any organic or inorganic chemicals, substances or materials
that can have negative impacts on human health and the environment when present
in large quantities and concentrations. It is primarily generated by industrial and
manufacturing processes and may have characteristics such as flammability, toxicity
and corrosiveness. Thus, pre-treatment before disposal or recycling is required [4].
The most effective approach for hazardous waste management is reduction at the
source (i.e., the green engineering approach). This could be achieved by modifying
the manufacturing processes to increase efficiency, using alternative compounds
and re-using or re-processing the waste streams. The secondary approach is to
reduce the volume, toxicity and hazardousness of the waste components for easier
disposal or recovery and re-use, by physical, chemical, biological and thermal
treatments. Physical treatments include the separation of chemical compounds from
solids or liquids using physical forces and mechanical devices. Examples of physical
treatments are: air stripping, carbon adsorption, centrifugation, distillation, liquid–
liquid extraction, sedimentation, ultrafiltration, etc. Chemical treatments refer to
the methods to neutralize, precipitate, oxidize or reduce chemical components as
2 Conventional Approaches for Waste Management …
Thermal treatment facilities are usually equipped with air pollution control (APC)
systems designed based on the waste feed composition, the thermal treatment technology and the specific emission limits applicable to the facility. The typical elements
and operating procedure of an APC syste are as follows [19]:
– Dioxins and furans are destructed by thermal treatment at high temperatures
(1000–1200 °C) and are captured by baghouse filter and activated carbon and/or
catalytic reactor adsorption
– Heavy metals are captured by baghouse filter and activated carbon and/or catalytic
reactor adsorption
– Particulates are captured through baghouse filter and/or electrostatic precipitator.
– A scrubbing section neutralizes acid gases (HCl, SO 2 ) through lime injection
The Canadian Council of Ministers of the Environment (CCME) has issued guidelines for the operation of municipal waste incinerators depending on the size of the
system. According to these regulations, units with more than 9.6 tonnes per day
capacity are required to follow strict emission standards and need to install a complete
APC system. The emission standards require periodic monitoring of the stack gas for
air pollutants concentration. Less strict emission standards (specific to each province)
apply to the units with lower capacities and they can only install a simple scrubber
system. In these systems cooled flue gas passes through an acid scrubber to reduce
or remove the acid gases (HCl, SO 2 ), while particulates and other contaminants can
be controlled inside the incinerator [19].
2.3 Conventional Approaches for Hazardous Solid Waste
Disposal
Hazardous waste is any organic or inorganic chemicals, substances or materials
that can have negative impacts on human health and the environment when present
in large quantities and concentrations. It is primarily generated by industrial and
manufacturing processes and may have characteristics such as flammability, toxicity
and corrosiveness. Thus, pre-treatment before disposal or recycling is required [4].
The most effective approach for hazardous waste management is reduction at the
source (i.e., the green engineering approach). This could be achieved by modifying
the manufacturing processes to increase efficiency, using alternative compounds
and re-using or re-processing the waste streams. The secondary approach is to
reduce the volume, toxicity and hazardousness of the waste components for easier
disposal or recovery and re-use, by physical, chemical, biological and thermal
treatments. Physical treatments include the separation of chemical compounds from
solids or liquids using physical forces and mechanical devices. Examples of physical
treatments are: air stripping, carbon adsorption, centrifugation, distillation, liquid–
liquid extraction, sedimentation, ultrafiltration, etc. Chemical treatments refer to
the methods to neutralize, precipitate, oxidize or reduce chemical components as