Life cycle analysis and sustainability assessment of advanced wastewater treatment technologies
| DOI | https://doi.org/10.1108/WJSTSD-05-2016-0034 |
| Pages | 169-185 |
| Published date | 03 April 2018 |
| Date | 03 April 2018 |
| Author | Sheetal Jaisingh Kamble,Anju Singh,Manoj Govind Kharat |
| Subject Matter | Public policy & environmental management,Environmental technology & innovation |
Life cycle analysis and
sustainability assessment of
advanced wastewater treatment
technologies
Sheetal Jaisingh Kamble, Anju Singh and Manoj Govind Kharat
Department of Environmental Engineering and Management,
Operations and Supply Chain Management,
National Institute of Industrial Engineering, Mumbai, India
Abstract
Purpose –Wastewater treatment plants (WWTPs) have long-time environmental impacts.
The purpose of this paper is to assess the environmental footprint of two advanced wastewater
treatment (WWT) technologies in a life cycle and sustainability perspective and identify the improvement
alternatives.
Design/methodo logy/approach –In this study life cycle-based environmental assessment of
two advanced WWT technologies (moving bed biofilm reactor (MBBR) and sequencing batch reactor
(SBR)) has been carried out to compare different technological options. Life cycle impacts were computed
using GaBi software employing the CML 2 (2010) methodology. Primary data were collected and analysed
through surveys and on-site visits to WWTPs. The present study attempts to achieve significantly
transparent results using life cycle assessment (LCA) in limited availability of data.
Findings –The results of both dire ct measurements in th e studied wastewater s ystems and the
LCA support the fact tha t advanced treatment h as the best environmen tal performance. The re sults
show that the operation ph ase contributes to nearl y 99 per cent for the impacts o f the plant. The study
identified emissions a ssociated with elect ricity production requ ired to operate the WWTPs , chemical
usage, emissions to wa ter from treated effluent and heavy metal em issions from waste sludge applied to
land are the major cont ributors for overall environmental imp acts. SBR is found to be the best option for
WWT as compared to MBBR in the urban context. In order t o improve the overall env ironmental
performance, the wast ewater recovery, th at is, reusable water s hould be improved. Fur ther, sludge
utilisation for energ y recovery should be co nsidered. The results of the study show that the avoided
impacts of energy recov ery can be even greater than direct impacts of g reenhouse gas emissions from the
wastewater system. Therefore, measures which combine reusing wastewater with energy generation
should be preferred. The study highlights the major sho rtcoming, i.e., the l ack of national life cyc le
inventories and databa ses in India limiting t he wide application of LC A in the context of envir onmental
decision making.
Research limitations/implications –The results of this study express only the environmental
impacts of the operation phase of WWT system and sludge management options. Therefore, it is
recommended that further LCAs studies should be carried o ut to investigate construction and
demolition phase and also there is need to reconsider the toxicological- and pathogen-related
impact categories. The results obtained through this type of LCA studies can be used in the
decision-making framework for selection of appropriate WWT technology by considering LCA results as one
of the attributes.
Practical implications –The results of LCA modelling show that though the environmental
impacts associated with advanced technologies are high, these technologies produce the good
reusable quality of effluent. In areas where water is scarce, governments should promote reusing
wastewater by providing additional treatment under safe conditions as much as possible with advanced
WWT. The LCA model for WWT and management planning can be used for the environmental assessment
of WWT technologies.
Originality/value –The current work provides a site-specific data on sustainable WWT and management.
The study contributes to the development of the regional reference input data for LCA (inventory
development) in the domain of wastewater management.
Keywords Sustainability assessment, Life cycle analysis, Moving bed biofilm reactor,
Sequencing batch reactor, Wastewater treatment technologies
Paper type Research paper
World Journal of Science,
Technology and Sustainable
Development
Vol. 15 No. 2, 2018
pp. 169-185
© Emerald PublishingLimited
2042-5945
DOI10.1108/WJSTSD-05-2016-0034
The current issue and full text archive of this journal is available on Emerald Insight at:
www.emeraldinsight.com/2042-5945.htm
169
Life cycle
analysis and
sustainability
assessment
1. Introduction
Sustainability is one of the main concerns globally, which is especially true when
considering indispensable, broad spectrum commodities such as water (Beery and Repke,
2010). With the increasing world population, as well as industrial and agriculture activities,
countries worldwide face growing global water stress, both in terms of water scarcity and
deteriorated quality (Zhou et al., 2011). Appropriate treatment of wastewater and further its
reuse can help to solve the problem of water scarcity as well as save valuable resources by
reducing the use of freshwater.
Although there has been considerable technological advancement, wastewater treatment
(WWT) is one of the major issues faced by the developing countries. The main function of a
wastewater treatment plant (WWTP) is to produce clean effluent by removing nutrients,
metals and organic pollutants present in the influent. Nowadays, WWT has multiple
functions and produces both clean effluents and sludge, which is increasingly seen as a
resource rather than a waste product and can be used for nutrients and energy recovery.
Thus, technological as well as management choices influence the performance of WWTPs.
To improve this performance, the trade-offs related to the different choices have to be
identified and assessed.
Many advanced technologies such as sequencing batch reactors (SBRs) and membrane
bioreactors (MBRs) have been developed for WWT. Generally, the choice of “best”WWT
technology is based first and foremost on economic and technical constraints (Bonton et al.,
2012). However, climate change, energy crisis, social aspects and other environmental
problems coming into focus make this choice more complicated. To provide the foundation
for a better choice, information on environmental aspects of different systems is thus needed
(Finnveden et al., 2009). Therefore, selection of appropriate technologies for WWT is a prime
challenge faced by the decision makers. The decision makers, however, do not have a
rational framework to compare WWT technologies. In this context, life cycle assessment
(LCA) can determine what choices provide the best environmental performance.
The environmental footprint of a given WWTP depends on the choice of technology
because any given treatment technology has a characteristic consumption of resources,
energy and chemicals. The footprint is also determined by the treatment objective
(e.g. disposal of treated wastewater after mere compliance with the prescribed regulatory
norms or production of high-quality water for recycling and reuse applications). There is
very limited knowledge available on the performance of existing technologies
and evaluation of those systems is very timely in order to derive sound conclusions and
recommendations for future wastewater management strategies in India. Further, new
technologies that should be introduced in India should be carefully selected, taking into
account the already existing experiences.
Therefore, in this study, environmental footprints of two advanced WWT technologies
namely: moving bed biofilm reactor (MBBR) and SBR are estimated and have been
compared using the life cycle approach. LCA will help to evaluate and to quantify the
potential environmental impacts ( footprint) due to respective processes and to compare
the processes using LCA metrics for each environmental effect.
The remainder of the paper is organised as follows: the following section presents the
brief literature review. Section 3 presents the methodology adopted in the study. The results
are discussed in Section 4. Finally, Section 5 presents the concluding remarks.
2. Literature review
LCA is becoming increasingly popular amongst researchers in WWT field nowadays
because of its holistic approach. LCA has proved as a useful tool for computation of the
environmental footprint of a given WWT technology (Hospido et al., 2004; Gallego et al.,
2008; Li et al., 2013).
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WJSTSD
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