used as fertilizer in agriculture field and in horticulture. It maintains the soil health
through increasing moisture-holding capacity and recycling nutrients into soil.
However, composting of field emits methane and foul odour (Banerjee et al.
2019). Also, it may cause contamination of soil with toxic materials (organic and
inorganic).
Anaerobic Digestion Composting of organic waste led to generation of biofuel
(comprising 50–60% of methane) using anaerobes (Banerjee et al. 2019). The
technique offers stabilization and disinfection of wastes like industrial sludge,
farmland residue and animal slurries. The value-added part of the process is that
the residue which is rich in nutrients and moisture can be used as fertilizer. Besides,
energy and efficiency recovery of anaerobic digestion are better than composting.
Incineration Wastes are converted into ash under high temperature (980–2000
C)
with the emission of gaseous products (Banerjee et al. 2019). It is a stepwise process
which leads to destruction of toxic material with recovery of energy from the wastes.
Incineration reduces the volume of combustible waste to 80–90%, thereby
facilitating the less requirement of land for its disposal (Banerjee et al. 2019).
Additionally, the process is odourless, noise-free and environmentally safe.
Pyrolysis In pyrolysis, wastes are thermally degraded in absence of oxygen under
the temperature ranged between 300 and 850
C. Synthetic gas (CH 4 , CO and H 2 )
and char (carbon and non-combustible materials) are the by-products of pyrolysis of
waste material (Banerjee et al., 2019). Gases are further utilized for fuel, wax and tar
production.
Gasification The process costs incentive and requires high power source. Gasification is a partial oxidation of wastes under insufficient oxygen condition under
temperature >650
C (Banerjee et al. 2019). In plasma gasification technology,
high temperature (electric arc) is applied to the waste, thereby converting it into an
inert residue (ash). Before thermal application, wastes are required to be dried and
then segregated. During the process, gases produced as by-product comprise of H 2 ,
CO and CH 4 , which can be used as fuel. Unlike incineration, gasification does not
emit any toxic gases like SOx and NOx because of insufficient oxygen.
Non-combustible residual parts are disposed following proper handling.
Refuse-Derived Fuel (RDF) Alike gasification, RDF is obtained from partial
oxidation of mixed municipal solid waste. Utilization of the fuel in combination
with coal and other type of conventional fuel in industries could be a great input in
minimizing the requirement of natural/synthetic fuel.
Landfilling This is the most common and ultimate way to manage all types of
wastes (organic and inorganic) which do not require skilled employees and is a
low-cost process. However, landfilling of wastes without proper pretreatment ranked
lowest amongst all management techniques. Landfills are major source of
16 Causes, Effects and Sustainable Approaches to Remediate Contaminated Soil
471
through increasing moisture-holding capacity and recycling nutrients into soil.
However, composting of field emits methane and foul odour (Banerjee et al.
2019). Also, it may cause contamination of soil with toxic materials (organic and
inorganic).
Anaerobic Digestion Composting of organic waste led to generation of biofuel
(comprising 50–60% of methane) using anaerobes (Banerjee et al. 2019). The
technique offers stabilization and disinfection of wastes like industrial sludge,
farmland residue and animal slurries. The value-added part of the process is that
the residue which is rich in nutrients and moisture can be used as fertilizer. Besides,
energy and efficiency recovery of anaerobic digestion are better than composting.
Incineration Wastes are converted into ash under high temperature (980–2000
C)
with the emission of gaseous products (Banerjee et al. 2019). It is a stepwise process
which leads to destruction of toxic material with recovery of energy from the wastes.
Incineration reduces the volume of combustible waste to 80–90%, thereby
facilitating the less requirement of land for its disposal (Banerjee et al. 2019).
Additionally, the process is odourless, noise-free and environmentally safe.
Pyrolysis In pyrolysis, wastes are thermally degraded in absence of oxygen under
the temperature ranged between 300 and 850
C. Synthetic gas (CH 4 , CO and H 2 )
and char (carbon and non-combustible materials) are the by-products of pyrolysis of
waste material (Banerjee et al., 2019). Gases are further utilized for fuel, wax and tar
production.
Gasification The process costs incentive and requires high power source. Gasification is a partial oxidation of wastes under insufficient oxygen condition under
temperature >650
C (Banerjee et al. 2019). In plasma gasification technology,
high temperature (electric arc) is applied to the waste, thereby converting it into an
inert residue (ash). Before thermal application, wastes are required to be dried and
then segregated. During the process, gases produced as by-product comprise of H 2 ,
CO and CH 4 , which can be used as fuel. Unlike incineration, gasification does not
emit any toxic gases like SOx and NOx because of insufficient oxygen.
Non-combustible residual parts are disposed following proper handling.
Refuse-Derived Fuel (RDF) Alike gasification, RDF is obtained from partial
oxidation of mixed municipal solid waste. Utilization of the fuel in combination
with coal and other type of conventional fuel in industries could be a great input in
minimizing the requirement of natural/synthetic fuel.
Landfilling This is the most common and ultimate way to manage all types of
wastes (organic and inorganic) which do not require skilled employees and is a
low-cost process. However, landfilling of wastes without proper pretreatment ranked
lowest amongst all management techniques. Landfills are major source of
16 Causes, Effects and Sustainable Approaches to Remediate Contaminated Soil
471