88
T. Gichamo et al.
soil filter, use of aquatic plants, and reuse of wastewater for irrigation ranked from
best to worst respectively.
Keywords VIKOR · Wastewater · Treatment · Natural
11.1 Introduction
The number of population in the world has almost doubled in the last fifty years,
the consumption pattern in association with climate change are putting significant
pressure generally on natural resources and specifically on water resources (Gichamo
and Gökçeku¸ s 2019; Sadr et al. 2018) and this resulted on a massive generation of
wastewater. In recent decades, fast industrialization and manufacturing aggravated
critical complications by directly releasing industrial wastes such as heavy metallic
ions, dyes, and organic food wastes to the aquatic environmental (Gichamo et al.
2020). A globally escalating wastewater release has forced the institutions to treat
wastewater and improve the quality before releasing it to the environment. Freshwater
scarcity and climate changes enforce the world to look at alternative sources of water
for consumptive demands.
Treating and reuse of wastewater is useful to fairly allocate limited water, and
to reduce environmental pollution (Ayyıldız and Özçelik 2018). In the last few
decades, quality standards have been increased for treated wastewater effluents that
subsequently increased power demands, technology advancement, and overall costs.
Conventional wastewater treatment infrastructures were commonly used and natural
wastewater treatment facilities also emerged as alternative techniques. The expensiveness of the conventional wastewater treatment methods created economic pressure even on developed nations therefore, innovative, cheap, environmentally friendly
methods are needed to manipulate wastewater (Tsaur et al. 2002). The selection of
appropriate wastewater treatment (WWT) methods for environmental safety, health,
and ecological sustainability depends on factors such as cost, energy consumption,
carbon emission, and technical requirements (Bottero et al. 2011; Sun et al. 2020).
Recently, different countries around the world have turned the face towards technically and economically feasible wastewater treatment solutions like natural wastewater treatment approaches, and a combination of natural and conventional WWT
methods.
Natural techniques of WWT predominately rely on natural techniques to treat
wastewater and it does not depend on external energy sources for major processing,
however, it may require pipes and pumps for conveyance (Crites et al. 2014a, b).
Natural WWT methods such as constructed wetlands, stabilization pond, reuse of
wastewater for irrigation, and aquatic plants are integrated WWT options that could
reduce waste load and at the same time may maintain ecological and environmentally
sustainable use, health and well-being (Mitsch 2012).
The cost that natural WWT techniques required is cheaper as compared with
conventional WWT methods. Treating a gallon of wastewater by natural method costs
T. Gichamo et al.
soil filter, use of aquatic plants, and reuse of wastewater for irrigation ranked from
best to worst respectively.
Keywords VIKOR · Wastewater · Treatment · Natural
11.1 Introduction
The number of population in the world has almost doubled in the last fifty years,
the consumption pattern in association with climate change are putting significant
pressure generally on natural resources and specifically on water resources (Gichamo
and Gökçeku¸ s 2019; Sadr et al. 2018) and this resulted on a massive generation of
wastewater. In recent decades, fast industrialization and manufacturing aggravated
critical complications by directly releasing industrial wastes such as heavy metallic
ions, dyes, and organic food wastes to the aquatic environmental (Gichamo et al.
2020). A globally escalating wastewater release has forced the institutions to treat
wastewater and improve the quality before releasing it to the environment. Freshwater
scarcity and climate changes enforce the world to look at alternative sources of water
for consumptive demands.
Treating and reuse of wastewater is useful to fairly allocate limited water, and
to reduce environmental pollution (Ayyıldız and Özçelik 2018). In the last few
decades, quality standards have been increased for treated wastewater effluents that
subsequently increased power demands, technology advancement, and overall costs.
Conventional wastewater treatment infrastructures were commonly used and natural
wastewater treatment facilities also emerged as alternative techniques. The expensiveness of the conventional wastewater treatment methods created economic pressure even on developed nations therefore, innovative, cheap, environmentally friendly
methods are needed to manipulate wastewater (Tsaur et al. 2002). The selection of
appropriate wastewater treatment (WWT) methods for environmental safety, health,
and ecological sustainability depends on factors such as cost, energy consumption,
carbon emission, and technical requirements (Bottero et al. 2011; Sun et al. 2020).
Recently, different countries around the world have turned the face towards technically and economically feasible wastewater treatment solutions like natural wastewater treatment approaches, and a combination of natural and conventional WWT
methods.
Natural techniques of WWT predominately rely on natural techniques to treat
wastewater and it does not depend on external energy sources for major processing,
however, it may require pipes and pumps for conveyance (Crites et al. 2014a, b).
Natural WWT methods such as constructed wetlands, stabilization pond, reuse of
wastewater for irrigation, and aquatic plants are integrated WWT options that could
reduce waste load and at the same time may maintain ecological and environmentally
sustainable use, health and well-being (Mitsch 2012).
The cost that natural WWT techniques required is cheaper as compared with
conventional WWT methods. Treating a gallon of wastewater by natural method costs