desizing, mercerizing, printing, dying, and packing which require huge amount of
organic chemicals of a complex structure (Goyal et al. 2009).
Significant environmental pollution is caused by textiles and dying; the problems
that occur mainly are high concentration of colorant (dyes) and organic matter that
have to be resistant to effects of light, oxidant, water soap, and sweat. For the
removal of colorant from textile wastewater, the most commonly used conventional
methods of treatments are biological, physical, and chemical treatment process.
However, due to the high chemical and operating costs, the physicochemical treatment processes can be unsuitable, and formation of by- products is often more
dangerous than degraded substances. CWs have proven to be an effective alternative
for treating wastewater, and the construction of low energy-consuming ecosystems
that use natural processes, in contrast to complex high-maintenance treatment
systems, will hopefully lead to more ecologically sustainable wastewater treatment
in the future (Goyal et al. 2009). In the use of constructed wetland for the textile
wastewater treatment, the main parameters identified using aquatic macrophytes are
chemical oxygen demand (COD), biological oxygen demand (BOD), total dissolved
solids (TDS), Ph, electric conductivity, chloride, sulfate, and other solution
substances.
Therefore, before being discharged to the environment, wastewater from textile
industry has to be treated. Various techniques and methods including anaerobic and
aerobic microbial degradation, chemical oxidation, coagulation, filtration, precipitation, electrochemical treatment, membrane separation, filtration, hydrogen peroxide
catalysis, flotation, reverse osmosis, ozonation, and biological techniques are used
for the removal of various pollutant forms of the textile industry wastewater.
In recent years, a considerable attention has been focused in recent years on
absorption process in which aquatic plants are used because of its advancement than
over conventional treatment methods which include minimization of chemical and
biological sludge, low cost, and high efficiency. Constructed wetland can be used to
achieve this purpose. The artificial wastewater treatment systems in constructed
wetland consisting of channels or shallow ponds in which aquatic plants have
been planted rely upon natural physical, chemical, biological, and microbial process
to treat wastewater. In natural wetland, ecological systems are the base for the
treatment system in constructed wetland. It is important to have a basic understanding of how natural wetlands work for the construction and designing of treatment
wetland and pollutant removal processes of constructed wetland. Thus, aquatic
macrophytes Eichhornia crassipes are used in constructing wetland to remove the
pH, EC, chloride, sulfate, phenols, BOD, and COD from the textile industrial
effluent (Goyal et al. 2009).
5.2.1 Role of Microbes, Plants, and Their Combined Roles in Dye
Degradation
Effect of different plants on azo dye wastewater decolorization: Every year, a
massive bulk of wastewater of azo dye is produced in textile industry. The
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S. Khan et al.
organic chemicals of a complex structure (Goyal et al. 2009).
Significant environmental pollution is caused by textiles and dying; the problems
that occur mainly are high concentration of colorant (dyes) and organic matter that
have to be resistant to effects of light, oxidant, water soap, and sweat. For the
removal of colorant from textile wastewater, the most commonly used conventional
methods of treatments are biological, physical, and chemical treatment process.
However, due to the high chemical and operating costs, the physicochemical treatment processes can be unsuitable, and formation of by- products is often more
dangerous than degraded substances. CWs have proven to be an effective alternative
for treating wastewater, and the construction of low energy-consuming ecosystems
that use natural processes, in contrast to complex high-maintenance treatment
systems, will hopefully lead to more ecologically sustainable wastewater treatment
in the future (Goyal et al. 2009). In the use of constructed wetland for the textile
wastewater treatment, the main parameters identified using aquatic macrophytes are
chemical oxygen demand (COD), biological oxygen demand (BOD), total dissolved
solids (TDS), Ph, electric conductivity, chloride, sulfate, and other solution
substances.
Therefore, before being discharged to the environment, wastewater from textile
industry has to be treated. Various techniques and methods including anaerobic and
aerobic microbial degradation, chemical oxidation, coagulation, filtration, precipitation, electrochemical treatment, membrane separation, filtration, hydrogen peroxide
catalysis, flotation, reverse osmosis, ozonation, and biological techniques are used
for the removal of various pollutant forms of the textile industry wastewater.
In recent years, a considerable attention has been focused in recent years on
absorption process in which aquatic plants are used because of its advancement than
over conventional treatment methods which include minimization of chemical and
biological sludge, low cost, and high efficiency. Constructed wetland can be used to
achieve this purpose. The artificial wastewater treatment systems in constructed
wetland consisting of channels or shallow ponds in which aquatic plants have
been planted rely upon natural physical, chemical, biological, and microbial process
to treat wastewater. In natural wetland, ecological systems are the base for the
treatment system in constructed wetland. It is important to have a basic understanding of how natural wetlands work for the construction and designing of treatment
wetland and pollutant removal processes of constructed wetland. Thus, aquatic
macrophytes Eichhornia crassipes are used in constructing wetland to remove the
pH, EC, chloride, sulfate, phenols, BOD, and COD from the textile industrial
effluent (Goyal et al. 2009).
5.2.1 Role of Microbes, Plants, and Their Combined Roles in Dye
Degradation
Effect of different plants on azo dye wastewater decolorization: Every year, a
massive bulk of wastewater of azo dye is produced in textile industry. The
148
S. Khan et al.