Treatment of Textile Wastewater Using Biochar Produced …
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compound is transformed into a simple complex or compounds possessing a higher
molecular weight, and the process is normally carried out at a temperature ranging
between 400 and 800 °C. Pyrolysis in turn differs from the natural combustion
process, and this process exclusively takes place in the absence of air, and there is nil
chance of oxidation to occur. The by-products of obtained as a result of this process
include biochar, bio-oil, and syngas.
The production of biochar involves the use of different agricultural feedstock
by subjecting the feedstock to the pyrolysis process at different temperatures. This
pyrolysis process is taking place inside a furnace under nitrogen environment. The
obtained samples were further sieved for the purpose of size reduction, and they were
cleansed with DI water to eliminate any contaminants present within it. The thus
obtained samples were further oven dried for later use [10]. The pyrolysis technique
is considered to be the most favourable one for the production of biochar on a
large scale. This technique can be further classified into conventional slow pyrolysis,
fast pyrolysis, and microwave assisted pyrolysis which in turn is completely based
on their operating conditions. These pyrolysis techniques cause a great variation in
composition of solids, liquids, and gases which in turn is completely dependent upon
its operating parameters like heating rate, temperature, and the residence time [11].
Biochar can be significantly prepared by adopting carbonization technique in which
the temperature varied from 200 to 400 °C, respectively [12].
1.5.1 Conventional Pyrolysis
Magnetic biochars are generally prepared by adopting conventional pyrolysis
method. In this method, heat transfer between the materials is mainly due to conduction, convection, and radiation methods. This method in turn involves the use of two
other processes namely carbonization and activation. In this process of carbonization, a non-porous char is produced when the temperature is between 600 and 900 °C
in the presence of an inert atmosphere. After this stage, it undergoes an activation
process in which the char contacted with an oxidizing gas namely CO 2 or steam at
a temperature of 600–1200 °C [13].
1.5.2 Biomass Pyrolysis
Wooden or agricultural biomass stored in a dedicated storage facility is transported
to the pyrolysis reactor via a bucket feeder. The raw biomass is pre-dried inside the
feeder through the use of hot and dry air flowing through the cross flow. Biomass
pre-drying has a positive impact on the reduction of the moisture content inside
the material by few percent. Pre-dried and pre-heated biomass gets into the pyrolysis
reactor where the following process takes place. All the moisture accumulated on the
raw biomass has to evaporate in order to initiate the carbonization process depending
on the type of biomass and moisture accumulated in the process material. In the next
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compound is transformed into a simple complex or compounds possessing a higher
molecular weight, and the process is normally carried out at a temperature ranging
between 400 and 800 °C. Pyrolysis in turn differs from the natural combustion
process, and this process exclusively takes place in the absence of air, and there is nil
chance of oxidation to occur. The by-products of obtained as a result of this process
include biochar, bio-oil, and syngas.
The production of biochar involves the use of different agricultural feedstock
by subjecting the feedstock to the pyrolysis process at different temperatures. This
pyrolysis process is taking place inside a furnace under nitrogen environment. The
obtained samples were further sieved for the purpose of size reduction, and they were
cleansed with DI water to eliminate any contaminants present within it. The thus
obtained samples were further oven dried for later use [10]. The pyrolysis technique
is considered to be the most favourable one for the production of biochar on a
large scale. This technique can be further classified into conventional slow pyrolysis,
fast pyrolysis, and microwave assisted pyrolysis which in turn is completely based
on their operating conditions. These pyrolysis techniques cause a great variation in
composition of solids, liquids, and gases which in turn is completely dependent upon
its operating parameters like heating rate, temperature, and the residence time [11].
Biochar can be significantly prepared by adopting carbonization technique in which
the temperature varied from 200 to 400 °C, respectively [12].
1.5.1 Conventional Pyrolysis
Magnetic biochars are generally prepared by adopting conventional pyrolysis
method. In this method, heat transfer between the materials is mainly due to conduction, convection, and radiation methods. This method in turn involves the use of two
other processes namely carbonization and activation. In this process of carbonization, a non-porous char is produced when the temperature is between 600 and 900 °C
in the presence of an inert atmosphere. After this stage, it undergoes an activation
process in which the char contacted with an oxidizing gas namely CO 2 or steam at
a temperature of 600–1200 °C [13].
1.5.2 Biomass Pyrolysis
Wooden or agricultural biomass stored in a dedicated storage facility is transported
to the pyrolysis reactor via a bucket feeder. The raw biomass is pre-dried inside the
feeder through the use of hot and dry air flowing through the cross flow. Biomass
pre-drying has a positive impact on the reduction of the moisture content inside
the material by few percent. Pre-dried and pre-heated biomass gets into the pyrolysis
reactor where the following process takes place. All the moisture accumulated on the
raw biomass has to evaporate in order to initiate the carbonization process depending
on the type of biomass and moisture accumulated in the process material. In the next