Eco-efficient Prototype of Wastewater Treatment Plant Applying Clean
Development Mechanism Methodologies Mediterranean Countries
FIRAS FAYSSAL
Doctoral School & Faculty of Engineering
Doctoral School of Science and Technology (EDST), Lebanese University & Higher School of
Engineering in Beirut, Saint Joseph University
B.P. 11-2806 Beirut & B.P. 17-5208 Mar Mikhael
LEBANON
ADEL MOURTADA
Doctoral School
Doctoral School of Science and Technology (EDST), Lebanese University
B.P. 11-2806 Beirut
LEBANON
MAZEN GHANDOUR
Faculty of Engineering
Faculty of Engineering, Lebanese University
B.P. 11-2806 Beirut
LEBANON
REMI DAOU
Higher School of Engineering in Beirut (ESIB), Saint Joseph University
B.P. 17-5208 Mar Mikhael, Beirut 1104 2020
LEBANON
Abstract: Municipal wastewater treatment is committed reducing greenhouse gases emissions in line with
United Nations Framework Convention on Climate Change (UNFCCC) norms in order to preserve Earth's
blanket and lower climate acute changes. Greenhouse gases emissions reduction is the avant-garde of municipal
wastewater treatment technologies; however, the process requires particular segmentation of all phases to
contain the excessive energy required for treatment. Consequently, Energy analysis is endorsed as essential to
sustain a thermodynamic equilibrium of the treatment plant with its environment. Decarbonization,
denitrification & phosphorus removal urge the exploitation of sustainable energy whether recovered or
renewable to engine the treatment facility. This literature values compile the eco-design of wastewater
treatment plant with the avant-garde technologies of greenhouse gases emissions reduction, considering
environmental aspects at all stages of treatment process, targeting the lowest possible environmental impact
throughout the plant life cycle to create a CO-free facility prototype. UNFCCC introduced the greenhouse
gases emissions definition in wastewater plants as a project design document for the Clean Development
Mechanism (CDM) project AM00801 activity. The literature adopted this project and submitted it as a friendly
user interface or a Software to model an Eco-efficient management strategy for wastewater treatment plant
aerobic activated sludge type with the offset of environmental footprint measures based on decision making
analysis, Input-output analysis, benchmarking and energy balance, net negative emissions including
environmental declaration assessing the life cycle from costing, management, and sustainability perspectives.
Key-Words: WWTP, Energy consumption, Aerobic Activated sludge, Life Cycle Assessment, Decision-
Making, Data Acquisition, Greenhouse Gas Emissions
Received: September 25, 2021. Revised: October 3, 2022. Accepted: November 12, 2022. Published: December 6, 2022.
1 Introduction
The United Nations (UN) declared in the
emissions gap report the GHG emissions
approximately 58.1 gigatons of CO2 equivalent
(GtCO2e) in 2019 [17], which leads to a significant
indication of surface water runoff and wastewater
discharge pollution specifically. However, the UN
through UNFCCC affirmed environmental policy
shifting in order to decrease waterways pollution.
Under the Kyoto Protocol, emission caps were set
for each Annex-I country [18], amounting in total to
an average reduction of 5.2% below the aggregate
emission level in 1990. Each country has a
predetermined target of emission reduction as
compared to 1990 level. No emission cap is
imposed on Non-Annex I countries [18]. However,
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
57
Volume 4, 2022
to encourage the participation of Non-Annex I in the
emission reduction process a mechanism known as
Clean Development Mechanism (CDM) has been
established. The carbon markets are a prominent
part of the response to climate change and have an
opportunity to demonstrate that they can be a
credible and central tool for future climate
mitigation. Therefore, developed countries agreed to
limit their GHG emissions, relative to the levels
emitted in 1990 or to substitute the excess emissions
with carbon trading by investing in emissions
reduction in non-developed countries (such as
Morocco & Lebanon subject matter of literature’s
case study). Municipal wastewater utilities are a
direct and effective target for regulation and control,
the matter that has been reflected in Kyoto Protocol
and all ensuing conventions and agreements such as
GHG emissions reduction process integration. Table
1 shows all emissions that currently are in common
practice for municipal WWTPs
Table 1: The global warming potential of six
major greenhouse gases [19]
Name of the Gas
Global
Warming
Potential
Atmospheric
Life ( years)
Water Vapor (H2O)
0.1 to 0.23
Few days
Carbon dioxide
(CO2)
1
5 to 200
Methane (CH4)
21
12
Nitrous oxide (N2O)
310
114
Hydrofluorocarbons
(HFC)
140 to 11,700
1.4 to 260
Perfluorocarbons
(PFC)
6,500 to 9,200
10,000 to
50,000
Sulfur hexafluoride
(SF6)
23,900
3200
GHG emissions reduction methods primarily
facilitate the decarbonization in all treatment
processes from preliminary to tertiary mainly
aeration at secondary phase and require energy in
form of electricity thus exploited methods should
account to decrease biological oxygen demand for
all point of sources, treatment and GHG emissions
reduction. CDM Mechanisms consider a baseline
project and leakage emissions from electricity
consumption and monitoring of electricity
generation for all influential detected types of
emissions throughout the treatment process (carbon
dioxide (CO2), methane (CH4), nitrous oxide
(N2O)). This literature is concerned mainly to
develop the AM0080 Project (Mitigation of
greenhouse gases emissions with treatment of
wastewater in aerobic wastewater treatment plants)
into an Eco-efficient project where an application of
sustainability assessment tools is translated into a
user-friendly interface (1) resuming the techno-
economic analyses, (2) systematically examining the
sustainability aspects of WWT processes, (3)
assessing all environmental, social and economic
dimensions, (4) recovering energy required for both
treatment functional processes and emissions
reduction processes through management of
resulting biosolids. The methodology adopted to
support informed decisions making via data
acquisition, filtration, benchmarking and decision-
making tools in order to assure the execution of
WWTP eco-design and instantaneous improvement
actions enhancing sustainability, without burden
shifting. The main focus in the literature is to
develop, upgrade, simulate and model the proposed
baseline project into a prototype exploiting most
available technologies of wastewater treatment in
Mediterranean Countries specifically Non-Annex I
countries (or non-developed countries).
2 Methods
2.1 Goal and scope definition
The goal of this study is to (1) innovate a user-
friendly interface (2) where embedded all simulated
models for an eco-efficient prototype WWTP (3)
involving all available technologies and
environmental analysis (4) comparing the life cycle
impacts to baseline project referring to CDM
mechanism (5) using applicable mathematical
algorithms and methods.
We shall evaluate four different management
strategies in that context for the purpose of
generating such software: (1) Data Acquisition (2)
Energy Balance (3) Life Cycle Assessment (4) GHG
emissions Definition & Reduction.
life cycle inventories involved both baseline and
project data on process simulation creating a record
of input and output flows for plants in Morocco
(UNFCCC Case study), Lebanon (All country’s
functional plants), Greece (the most advanced AAS
plants) & France (Self-sufficient WWTPs AAS).
Such sampling included inputs of wastewater
parameters, energy consumption, and emissions
releases based on comparable data (Mediterranean
countries) of both industrial, developing and non-
developed countries. This study is innovative in
inaugurating, for further expansion of focused
economic and energy performance, a valid
referential comparative of WWTPs in countries at
Mediterranean coasts using types and technologies
other than the study subject matter (AAS).
In line with UN regulations, Mediterranean
municipalities are mandated to implement GHG
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
58
Volume 4, 2022
emissions reductions guidelines that are ultimately
on paper with the goal of protecting Mediterranean
surface water and improving environmental quality
that entails eventually the exploitation of novel
treatment technologies [20]. However, the cost of
implementation is typically the major factor for
decision making. Accordingly, technologists and
legislators shall benefit of the current literature
outcomes either the environmental impacts fallouts
using LCA or the economical results using CDM
project accreditations through CO2e savings or CER
(certified emission reduction or carbon Credit which
is the reduction of 1 ton of CO2 emission from the
baseline project activity) which can be evaluated in
terms of energy saving. This study is based on a set
of equations extracted from CDM mechanisms and
algorithms formulated on JMP Pro14, rendered and
simulated into models on MATLAB.
The outcome is gathered up on a user-friendly
interface which is the resulting Software of the
literature out of flexibility and ease of use
considerations with commercial intents. The target
of the literature defined in the submitted proposal to
the CDM committee embodied in the resulting
software, is to enhance Carbon Trading through
different approaches included and implemented in
the submission. The current submission concerns
are the following: (1) Energy efficiency for new or
makeover projects (existing or proposed baseline
plant) by means of energy recovery and exploitation
of allowable renewable energy (including and not
limited to: Cogeneration, installing an anaerobic
digester, improvements or switching to less carbon
intensive energy sources, solid management,
Reducing the frequency of the transport activity) (2)
Environmental Impact (including and not limited to:
LCA, LCI, LCAI) (3) Resulting reduction of any
category of greenhouse gas emissions.
In this study, the mined for performing data to be
incorporated into a master list establishing the
adopted scenarios, are: (1) the baseline set by
UNFCCC at Fès Morocco, (2) the mean WWTP in
Lebanon (referring to CDR study), (3) Greece self-
sufficient plant parameters [21], (4) France Neutral
plant parameters [22]. All reported data from sample
WWTPs were given equal weight in this study and
reference was always the CDM mechanisms listed
baseline parameters to develop an eco-efficient
prototype with three different levels of energy
efficiencies (listed scenarios). In condensing this
grouping to one prototype WWTP processes for an
Open input-output LCA adjustment, the resulting
linear mean of values was used for the process
inventory. The intention of this method was to
create a process representative of the project set by
CDM program by taking surveyed data of
Mediterranean countries from multiple significant
plants. This assumes that studied and surveyed
plants are representative of plants as a whole and
that the data acquisition method has comparable
results to the set baseline uncertainty analysis for
discussion characterized the potential impacts of the
variability in literature values and addressed
possible alternative assumptions. Values from
adopted scenarios are used to put boundaries and
deduce benchmarks on emissions and energy
consumptions for baseline used technologies and
proposed project submission CDM-PDD. No
alternatives were addressed as all varied operating
conditions and necessary inputs as suggested in
baseline and from modeled acquired parameters and
variables, were included and simulated without
detected flaws. The outcome of modeled values was
proposed for the new inventories and reassessed for
the environmental impact study applied to the
baseline project. Differences between proposed
scenarios were highlighted in models with mention
to potential grounds and odds and adjustment
coefficient was integrated to emissions equations to
unify the study of different means.
2.2 System Boundaries
The current study implemented a combination of
novel technologies in WWT sector with the
intention of meeting GHG emissions reduction goal
set by CDM mechanism and as such uses the best
mechanical, chemical & biological practices to
assure energy self-sufficiency or neutrality of the
project plant; which allows decision-makers to
easily compare the estimated financial &
environmental impacts incurred by meeting the set
goals.
The functional unit for comparison in this study is
kilogram (kg) of CO2 equivalent removed or saved.
Figure 1: System Boundaries Energy Weight in &
out
Comparisons were performed based on total supply
chain environmental impacts, with highlights on the
local energy consumption and fugitive emissions
due to their high impacts. The approved
methodology included in PDD-CDM submission
assumed high energy consumption and fugitive
emissions that have relatively simple computation
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
59
Volume 4, 2022
and expected to have a useful lifetime of 20 years as
per baseline definitions. In order to tender a set of
algorithms adjusting to parameters’ variations to
define an immediate precise carbon footprint
calculator, data acquisition method, energy balance
process and LCA of baseline WWTP, comparable
scenarios should be well investigated accordingly.
Figure 2: Carbon Footprint Calculation Scheme
ISO14067
2.3 Scenarios Description
The default scenario is a simple AAS WWTP at Fès
Morocco with defined parameters and variants
through the AM0080 program. the bar against which
all other scenarios are compared have been selected
based on variables that should be controlled with
both lower and higher limits.
Lowest
BOD5
Lowest
COD
kWh/m³-
billing
Highest
BOD5
Highest
COD
137.98
289.07
0.842
294.55
644.4
82
238
1.77
449
707
192
521
1.58
491
1375
164
468
0.24
515
1181
42
321.5
8.68
241.33
496.5
35
273
2.6
310.67
651.8
87.25
298.63
1.17
404.5
765.38
307.36
784.8
0.8
633
1990.4
Table 1: default scenario of WWTPs AAS
Parameters & Indicators
the approved scenarios by the CDM committee
were restricted to a single mean sample from
each of France, Greece, Morocco & Lebanon.
Knowing that parameters extracted from France
& Greece plants represent factual data
acquisition from the year 2020 along with listed
parameters for Morocco Fès plant (baseline)
and mean parameters from Lebanon plants also
for year 2020
2.4. Process Description
2.4.1. Data Acquisition & Fault Detection
Method
Data validation, online monitoring of difficult-to-
measure variables, predictive maintenance, system
and energy optimization, and targeted water reuse
are the essentials of big data focus to improve
WWTP operations. Therefore, big data integration
will have the greatest influence on process control at
the WWTP to monitor and manage treatment
operations, for both upper and lower limits of
process variables. Data from case study WWTPs is
collected at various times, ranging from continuous
online sensor measurements to quarterly laboratory
results. Due to the difficulty of combining data of
multiple frequencies and formats, traditional data
management separates data by source. Scaling data
to a single time period is a popular mathematical
strategy for dealing with varied data frequencies.
However, because WWTP data are time-dependent,
co-correlated and the relationships among variables
are related to one another, and nonlinearly related,
this method cannot be used for datasets with a
considerable difference in frequencies. Effluent
quality variables can change differently over time
(Table 2), and they frequently change nonlinearly in
connection to other process variables, making it
difficult to pinpoint the reason for change between
sample events. The frequency with which the
treatment process is monitored is highly dependent
on the analysis' purpose and the process' parameters.
Timescale
Feature
Slow (days-weeks)
Solids retention time (SRT)
Hydraulic retention time (HRT)
Transmembrane pressure (TMP)
Fast (seconds-minutes)
Dissolved oxygen (DO)
Nutrient concentrations
Turbidity
Conductivity
Flowrate
Table 2: Time Lap of WWTP AAS Pollutant
Proceeding
Due to all aforesaid, the combination between
MCDM (Multicriteria Decision Making) and
stepwise regression methods has been found the best
method to represent the irregular nonlinearity of
WWTPs case study behaviour and achieve a
correlation that can be read by the indicator model
itself and through the established bridge model
between different correlated parameters on loophole
basis [11]. All models of the study hereinafter
basically are likewise based and all nonlinear trends
reflected thru the models and bridge models. If
nonlinear and nonstationary activity is found,
modelling nonstationary behaviour can be done in
one of two ways: accounting for a known, or
predicted, underlying trend, or limiting the temporal
window over which a model is trained. Given the
difficulty of modelling nonstationary behaviour in
the WWTP (Table 3) small time frames may be the
best option for achieving approximation stationary
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
60
Volume 4, 2022
and normal behaviour, which is the case of analysed
prototype.
Feature
Frequency
Structur
e
Proceeding
Water quality
Daily-
Monthly
Numer
ic
5-day biochemical oxygen demand,
alkalinity, nutrients
Water quality
Second-
Minute
Numer
ic
Temperature, dissolved oxygen, pH,
nutrient concentrations: sensors
Equipment
monitoring
Second-
Minute
Categ
orical
Power status
Equipment
monitoring
Second-
Minute
Numer
ic
Operating speed, flowrate, pressure
Operating
setpoints
Second-
Minute
Categ
orical
Peak or normal operation for flow
Operating
setpoints
Second-
Minute
Numer
ic
Runtime for batch operations
Table 3: Monitoring Proceedings in WWTPs
Sampling with Data Acquisition Frequency and
Model
Model-based control could be used to forecast what
a variable value should be under particular
situations. Model predictive control contrasts
predictions from mechanistic models with real
process observations. Then defects are discovered as
deviations from the model. The model can be
derived from theory or empirical trends and can be
used to approximate new process variables. Instead
of directly monitoring the variable of interest, a
relationship between variables can be discovered,
which exactly was the basis of the current study
models’ connection due to the complexity and
variability of parameters and indicators. Therefore,
it is essential to comprehend the entire strategy of
data acquisition and clustering process, in order to
proceed in a planned, target-oriented method and to
secure the utmost possible conclusion.
Consequently, frameworks for formalizing the
knowledge encounter process have been developed
through experimental feedback and mathematical
applicable processes. These process models explain
the knowledge outcome project's life cycle and give
a roadmap for executing similar projects under any
comparable circumstances. The UNFCCC AM0080
Pilot project depicts the process model used in the
procedures discussed in the submission. The model,
that can be generalized at the scale of
standardization to all WWTPs subject matter, is
based on a combination of an industry-oriented
standard process for DA model and created by a
consortium of significant proven algorithms
reflecting models of all required and necessary
applicable KPI’s for AAS WWTPs type. Hereafter a
detailed elaboration shows the adopted algorithms
and models of all indicators leading to GHGs
emissions arithmetical definition. The process is
engineered of six interconnected, highly
participatory, and iterative phases: (1) A thorough
understanding of the issue defining problems and
setting objectives are the start in this stage based on
strong relativity indicators. (2) Data comprehension,
after all data is collected, verified, and merged, is
essential to acquire prior knowledge of raw data
extracted from plant management. The data's
relevance in relation to the objectives shall be
confirmed at that stage. (3) Preparation of data at
that phase determines which data will be used and in
what format. As a result, this step includes
significance testing, data cleansing, deriving new
attributes, and feature selection and extraction. The
data is now in a format that can be used with the
tools chosen in the first stage. Bugs are being
filtered with a specific regression model as shown
hereinafter. (4) Many approaches could be used to
extract knowledge from the pre-processed DA.
Extracted knowledge can take any shape, such as a
list of rules or a model which is the case witnessed
after generating all KPI’s models. This phase
evaluates accuracy and generality. (5) Assessment
of newly acquired information is the process to
interpret and segregate outcomes between normal
feedback (Déjà vu) and new data requiring further
assessment. If there are any new or intriguing
patterns, they shall be recorded and the model notes
here a looping to rectify according to the corrected
pattern. Within the guidelines noted in CDM
mechanisms, all feedback should be processed as
repetitive knowing all parameters. (6) The
deployment of the system is all about deciding on a
distribution strategy: What should be done with the
newfound information? and where should it be
applied? Upon trials and debugging the answers
shall apply in due course and reflected in generated
models. Briefly, Process abnormalities in WWTPs
case study subject matter can be caused by a variety
of system failures or changes in circumstances. A
change in influent quality, an outbreak of treatment-
inhibiting microorganisms, irregularities or damage
to treatment units, mechanical failures, or sensor
failure are all examples to crucial circumstances that
might undergo the DA and modelling/modelled
process. When creating a fault detection
algorithm/software, it's fundamental to think about
how versatile an analytical technique is, and what
kind and range of errors should be recognized.
Many variables could be changed if a sensor fails,
especially that the sensor's measurements are used
in a control loop which would duplicate the error at
every chain of data processing. A sensor
malfunction, on the other hand, may only influence
the measured sensor variable if the sensor's
measurements are not included in a control loop.
Control charts are the most important tools for
determining whether a process is in control at a
glance. As well as the principal component analysis
method that is a widely used statistical method for
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
61
Volume 4, 2022
continuous monitoring of a wide range of variables.
It captures the correlations between linear
combinations of variables rather than the variables
themselves. Beside the main statistical role, the
partial least squares method can detect errors in a
separate linear combination of the measured
variables in the same way as executing the initial
data pool of extrapolated WWTPs [15].
Decision Making is the adaptive or flexible decision
method that can be used in uncertain conditions, as
due to the fact that the future of WWTPs is
uncertain and unpredictable, robust options tend to
be more recommended than optimal options. On the
other hand, the best option is more suitable when the
future can be predicted [14]. The purpose of
decision making is to identify full-bodied strategies,
which can adapt or perform well under uncertain
situations in the future. The method is helpful for
decision makers in long-term consequences. The
fundamental steps for automated decision making
are to: (1) identify the issues and set a goal; (2) find
information, strategies, risks and select a robust
strategy; (3) take an active towards the goals; (4)
determine whether the strategy is effective; and (5)
update and resolve the strategy. The last step is an
essential one because if the strategy is not effective,
decision makers can change strategies until they
meet their goals [12]. Pilot project didn’t adopt any
automated decision-making methodology, therefore
the PDD submission had to assure MCDM as the
decision-making methodology to be followed for all
ascended uncertainties along with stepwise
regression logic where necessary and control charts
logic for fault detection. Finally, the summarization
logic is used to gather all models to extract the
GHGs emissions as a linear trend according to all
variabilities imposed by change of parameters.
Figure 3: Framework of Data Acquisition & Method
Selection
2.4.2 Energy Balance Process
Wastewater utilities consume approximately 2% to
4% of the power at national level as an average at
all Mediterranean case study countries, which is
typically obtained from the grid. WWTP’s
secondary treatment phase is the processes
consuming the largest quantities of power. Reducing
process energy consumption in WWTP starts with a
process energy survey. The mission of this study is
to provide all conceivable aspects that may help in
the transition to energy neutrality in WWTPs with
comparable examples from industrial developed
countries (France in our case study), which will be
expanded further in this literature using arithmetic
models based on UNFCCC methodologies. The
sources of energy in wastewater were explored, as
well as several indicators for expressing energy
consumption, using experimental cases of
operational WWTPs in the Mediterranean countries:
Lebanon (non-developed countries’ sample),
Morocco (baseline case as indicated in AM0080
project), Greece (Developed country with high
potentials of sustainability) and France (Industrial
developed country with energy neutral plants
comparable case study). The operational methods
and technology upgrades of the WWT processes
were assessed, as well as the different lanes for
energy consumption reductions. The methods for
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
62
Volume 4, 2022
recovering the potential energy hidden in
wastewater, as well as the use of renewable energies
in WWTPs, were then explained and modelled. The
available assessment methodologies were
introduced, which may support the analysis and
comparison of WWTPs in terms of energy and GHG
emissions. Finally, successful case studies on
WWTP energy self-sufficiency were listed in a
threshold prototype comparable to baseline project
and its potential advancement. The literature’s
innovative project, the Software, was presented after
analysing the results and discussing energy saving
strategies and energy conservation measures in
order to reach the GHG emissions computation
through the models simulating energy requirements
and potential savings for WWTPs. For this purpose,
wastewater industry's energy demand, distribution
and performance were projected to account for an
average of 1.8% of all electricity consumed at the
national level for developed Mediterranean
countries depending always on country’s energy
sustainability approaches with differences in
relativity and data availability. However, WWT and
transportation sectors consume approximately 3% of
total electrical power produced in a non-developed
country according to the annual report of energy
consumption worldwide published by UN Stats, the
statistics division of UN [2]. Nevertheless, all
studies anticipated an increase of at least 20%
within the next decade to the amount of power
required for WWT in non-developed and newly
developed countries, leading to a significant
increase in CO2 emissions and resource
consumption. The amount of energy used to treat
wastewater is influenced by a variety of factors and
determined by the following: the location of the
plant, its size, the type of treatment process and
aeration system used, the effluent quality criteria,
the facility's age and lifetime and the operators'
expertise and abilities. Despite the fact that the
average energy consumption per cubic meter of
treated wastewater (kWh/m3) is rather consistent
between countries, the amount of energy required
for operations varies greatly amongst WWTPs and
requires more accurate indicators to reflect the
actual status. For analysed WWTPs, the reported
figures on specific energy consumption range from
0.25 kWh/m3 to 0.50 kWh/m3 [2] . For WWTPs
using modern biological removal systems with
multiple energy-saving techniques, the reported
figures on specific energy consumption can be as
low as 0.25 kWh/m3 [7]. The climate in which the
WWTPs were run proved to have only a slight
impact on energy consumption, with colder
temperature circumstances possibly resulting in
lower energy consumption than hot and humid
environments [15]. Consequently, the provided
results from CDM baseline indicated that the target
average energy consumption of WWTPs was around
0.06 kWh/m3 to 0.20 kWh/m3 without being able to
precise a threshold due to the lack of benchmark,
which was much lower in certain more developed
countries. Regardless of the size of the WWTP, the
biological treatment phase consumes the majority of
energy required for the whole plant, which can
account for up to 75% of total consumption [15].
Figure 4: AAS WWTP Power Consumption
Distribution
Approaches to Energy Balance in AM0080 Pilot
Project:
wastewater contains a quantity of energy that can be
recovered, proven thermal energy content estimated
at 75kWh/P.E./a, proven energy potential from
organic matter estimated at 153kWh/P.E./a [9], and
proven hydraulic potential energy depending on
inflow rate and available hydraulic height.
Moreover, wastewater energy consumption is
relevant to national electric energy consumption
accounting approximately for 30% of total energy
consumption of municipalities. The electric energy
saving potential is high and proven estimated at
around 25% [15]. The proven recovery from biogas
production is around 17kWh/P.E./a of electric
energy and 27kWh/P.E./a of recuperable thermal
energy [2]. A detailed analysis of the applicability
of these facts of energy consumption, saving and
balance to the AM0080 pilot project are well
elaborated in the generated models and simulation.
Figure 5 below shows the typical energy flows
produced by AAS digestion in Fès WWTP, that
convert the chemical energy content of COD to
electricity and thermal energy. Consequently, the
biogas energy recovery can cover up to 62% of total
energy requirements. (Refer to the biogas model
renewable energy section hereafter). the energy
balance of conventional WWTPs shows that the
most important energy consumers are the aeration
system (60%), wastewater pumping (12%) and
anaerobic digestion (11%), which together account
for the 83% of global energy consumption of the
plants [10]. The main purpose of determining the
role of energy efficiency in sustainable WWT
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
63
Volume 4, 2022
processes for AM0080 is to reach an optimum
prototype AAS WWTP where all energy recovery
and external renewable resources are ultimately
used and GHGs emissions are diminished to the
maximum possible [8].
Figure 5: GHG emissions during treatment process
at Fes WWTP
This study adopts proven theoretical methods to
produce models on energy efficiency, evaluating
appropriate sustainable WWT technologies, and
applying to the pilot project. Energy efficiency plays
multiple roles such as sustainable growth and
advancement, and economic development through
the application of the set mechanism. It can also
lead to carbon minimization resulting in reducing
climate change however many exclusions for the
sake of simplification were applied by CDM to
avoid an optimum GHG emissions reduction.
A- Design Process Guidance: is a circular process
that aims at continual development over time and
require beside a robust methodology, starting with
predesign operational advanced technologies
(mechanical, biological & chemical), accurate DA,
steady LCA and LCC, some technologies that
provide a fast data input combination and decision
making that would be achieved through IoT.
Relying to a complete structure of control, WWTP
function should follow a complex hierarchy based
on both input data and results at the same time. All
predesign measurements were reported by CDM as
included in Fes’s pilot project AM0080, the current
mechanism according to both tender document,
execution and operational records. Some of the main
design measures audited, surveyed, simulated and
modelled in this literature are: (1) Pumping: pumps
selection, pumping system peak, Continuous
calculation of system energy performance,
Evaluation of cost assessment including energy,
operation and maintenance costs, Equipment
management. All these factors were considered in
AM0080 methodologies and included in related
framed equations and tools [4]. (2) Aeration systems
of the Fès facility in the secondary treatment process
account require up to 30-60% of total energy used at
the conventional AS WWT system [7]. Adding
dissolve oxygen sensors and automatic controller,
fine bubble diffusers, proper blowers, and variable
speed motors, assure constant evaluation of oxygen
need and DO control all over the clock. All these
factors were translated into equations and
algorithms rather than models to be incorporated in
software. (3) Solids Handling: Solid volume
reduction ensures energy requirement and solid
handling. Anaerobic digestion is the method
implemented in this pilot project generating biogas
production and heat. All mentioned factors were
translated into equations and algorithms rather than
models to be incorporated in software. (4)
Ultraviolet system method is partially used for
tertiary treatment so the disinfection system takes
place at WWT facility. The upgrade of this option
further than baseline conditions was disregarded.
Figure 6: Energy self-sufficient WWTP Process,
Theoretical Analysis to Practice
Each technology has different removal efficiency
and can be evaluated on past experience, full-scale,
or pilot studies. Existing pilot project is a baseline
considered as the reference to the additions made.
Process
Recommendations
Energy
Savings
(%)
Influent
Pumping
Pump Control based on flow
10%
Conducting Inflow & Infiltration
long term analysis
35%
Rehabilitation of Pumps
20%
Aeration
Short Term strategy: Mixers off
with Aerator On
90%
Short Term strategy: Replace DO
meter
10%
Long Term strategy: integrate DO
meter to control
40%
UV
disinfectio
n
Short Term strategy: Replacing
Bulbs with low emissions
50%
Solid
Handling
Retrofitting sludge feeding
network from thickener
100%
Table 4: Energy Saving Recommendations on
Mechanical Process
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
64
Volume 4, 2022
Figure 7: Initial Model Scope of Work
B- Resource Recovery: Two nutrients in wastewater
are phosphorus and nitrogen can be used to produce
fertilizer and reduce GHGs emissions. Furthermore,
landfill gas technologies can capture methane or
biogas using anaerobic digesters. These
technologies should be applied for resource
recovery in WWTPs [15]. The pilot project
disregarded these two essentials energy recovery
factors that have been added to the PDD submission
after being simulated and modelled.
Figure 8: Recovery Diagram in Fès WWTP
Figure 9: Energy utilization diagram of Fes WWTP
C- Renewable Energy Exploitation: The WWTSs
should save energy consumption by reducing energy
used and implementing technologies that can
produce renewable energy [16]. Local governments
should consider applying energy-saving measures in
WWT facilities [11]. The goal is to improve energy
efficiency in the plant. WWTP at Fès considered
developing less energy consuming equipment
however no renewable energy has been exploited to
make Fès zero energy plant. PDD considered this
criterion as an essential factor of developing
additions whether solar or wind that are both
simulated and modelled.
2.4.3. Life Cycle Assessment & Life Cycle
Costing
Technological advancements highlighted in CDM
mechanisms are paving the way for new behaviours
to support the circular economy by recovering
resources from wastewater. The use of LCA and
LCC in the development of technical solutions for
treating wastewater and recovering by-products is a
prerequisite by UNFCCC pilot project submission
which is evaluated based on employing unique
novel technology configuration to process and
recover wastewater. Therefore, the current
assessment focuses on finding hotspots and potential
design improvements. Furthermore, the construction
of a unified strategy for projected LCA and LCC is
demonstrated in order to improve the robustness and
consistency of the project pilot systems' analysis.
The impact and cost of treatment are significantly
depending on the effluent composition, according to
the investigation specifically, whether the recovery
of biogas and treatment of wastewater can offset the
treatment systems' impact and expense. preliminary
analysis indicated that this is achievable. For the
baseline study, estimates of GHG emissions were
acceptable with many exclusions considered.
However, adding all excluded sources of GHG
emissions to the baseline, it is predicted to reduce at
full scale the energy consumption, as well as
operational costs and increase revenues at the level
of emissions CERs and expenses saving.
The LCA technique adopted follows ISO 14040 and
14044 as recommended by AM0080 program
guidelines [6]. As a result, it is believed that
comparable available resources are much cheaper at
the level of emissions yet the energy neutrality of
WWTP necessitates the neutrality of environmental
impact, accordingly a project-wide methodology has
been established out of the existing pilot project.
The initial stage's goals are to compare each
baseline set by CDM to the reference case or
simulated baseline formulated in that study, while
the project's ultimate and final goal is to compare
each of the baseline and monitoring for both DA
(with and without exclusions). Background data was
gathered from the CDM methodologies and tools.
Additional data is based on bench scale
measurements and simulations with the addition the
study proposed to the UNFCCC program. The
simulation achieved in the current analysis can
calculate a variety of geochemical processes
involving wastewater and biogas emissions, beside
sludge management. the technology units employed
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
65
Volume 4, 2022
in the pilot project from which data was obtained
are well defined, referring to ISO 14040 and 14044
[6]. The scope of this study is limited to the major
actor of financial and environmental LCC, which
comprised listed purchase costs (CAPEX) by CDM
in tender project, operational costs such as energy
and other resource consumption, maintenance and
repair expenses (OPEX), and end-of-life costs such
as collection and recycling costs. Revenues from
recovered by-products are also accounted for as
negative costs (except recovered energy) [1]. The
pilot project is indicated to have a 20 years life span
as a functional plant (15 years is the standard
lifetime set for WWTP). Nonetheless, the project's
next steps (UNFCCC submission) are to be
conducted with a comprehensive environmental
LCC, which will include both internal and
monetized external environmental costs, such as
those related to global warming once defined by the
Software subject matter. The chain of process below
represents the integrated Method approaching LCA
& LCC with the goals of aligning the overall
approach and main LCA components; develop an
understanding of the project pilot, technologies,
data, and simulation challenges; provide an initial
LCA and LCC and identify the main hotspots; and
identify preliminary design implications and where
additional efforts to improve data quality may be
required.
Figure 10: Flowchart of LCA & LCC Approach
Phases
The AS treatment system has substantially higher
energy requirements than any other treatment type
due to the aeration machinery operating almost all
day [2].
Equipment
Power
kW
Operation
Time
Control
Aerator
56
Continuous
VFD fixed
speed
Centrifuges
30
10 to 20
hrs./week
VFD flow
speed
Influent
Pumps
13
Continuous
VFD flow
speed
Blowers
11
Intermittent
Fixed Speed
Mixers
3
Continuous
Fixed Speed
UV System
7
Continuous
Fixed Bank
Table 5: Major Energy Consumers for WWTP AAS
These findings are consistent with pilot project
operations factsheets. The biggest contributor to the
effect categories of abiotic depletion and global
warming is energy consumption by fossil fuel and
electricity, which explains why AS has a higher
impact among all categories [13]. The objective of
the study beside the software, is the background
engine where all indicators the most important
amongst energy consumption, benchmarking,
recovery and renewables, to be well reflected
through numerical trends and algorithmic models
screening the evolution and interaction of each
factor and parameter. The objective of establishing a
set of key performance indicators computed and
modelled is to gather all models with a convenient
correlation algorithm that defines bottom line an
accurate amount of resulting GHGs emissions from
treatment process referring to CDM mechanism,
AM0080 project and tools specifically [3].
Figure 11: GHG Emissions Sources & Category
3.GHG Emissions Reductions
The approach for calculating and analysing the
carbon footprint of baseline WWTP is extended
from the CDM booklet by UNFCCC [3].
Accordingly, CF minimization has been prioritized
to include in plants: Electricity, heat, chemicals,
fossil fuels, transportation, and more with the code’s
advancement, however, GHG emissions considered
CO2, CH4, and N2O main emissions to be assessed
as a part of Kyoto Protocol. The assessment may be
used at two stages of the CF reduction process: (1)
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
66
Volume 4, 2022
while deciding on a plan to minimize GHG
emissions, the CF identifies the elements that have
the largest environmental effect; (2) CF evaluates
the efficacy of the actions taken to improve the
energy balance. Furthermore, calculating the CF
allows WWTPs management to control GHG
emissions contributions [5]. Through the AM0080
project, the UNFCCC encouraged the evaluation of
the CF of WWTPs from a life cycle perspective and
offered a pilot project to standardize a set of
equations to define the CF. The goal of this study is
to turn this pilot project into a generic software
system based on proven models and algorithms. CF
calculation approach throughout the course of a
plant's complete life cycle, splits the required LCCI
data into two categories: direct & indirect emissions.
However, plants are considered mixing both
categories. Direct emissions are those controlled by
the plant management system having no previous or
subsequent technical history data inputs and outputs
of plant’s items causing GHG emissions. The
complex model simulated in that study as the final
result succeeded to define both emissions types and
assure a better understanding of the result of energy
efficiency and balance proposed at the phase of
predesign or rehabilitation. Several different steps
may be taken to achieve complete energy neutrality
in WWTPs. The first major step would be reducing
the current energy consumption of WWTPs which
ranged between 0.25 to 1 kWh/m3 based on the
mathematical calculation following the guidelines of
AM0080 methodology. The most promising
reviewed operational measures to reduce the energy
consumption comprised aeration control strategies
since aeration held the biggest share of the total
energy consumption in Fès AAS WWTPs.
However, innovating a LCA & LCC model (with
the assistance of RETSCREEN as a feasibility
portal for technical projects) helped to achieve
further energy savings. Novel control systems,
presuming IoT in our case, proved the possibility of
significant reduction of energy for aeration,
pumping, agitators, blowers reaching off more than
25% of the time while maintaining the same
wastewater effluent standards. Furthermore,
chemical and biological applications such as
upgrades to nitrogen removal were able to reduce
the required aeration energy by more than 60%
using these new technological pathways of
treatment. The second step towards energy
neutrality was the increasing of on-site energy
production by energy recovery through biogas
sludge outcome production coupled with CHP
engines and emphasis on renewable resources such
as solar. The remaining electricity demand was
managed to be recovered mainly by organic waste
co-digestion to assure energy neutrality yet positive
energy production. Reviewing all these successful
methodologies in terms of energy self-sufficiency,
linked to an executed monitored plant (Fès) proved
the point that the predesigned or existing inefficient
WWTPs should take a series of actions as reviewed
in this literature to be turned into energy positive
plants. Analysing the priorities of the actions
separately, the literature proposed a CDM-PDD
submission according to the resulting calculations
and established a set of algorithms and models on
MATLAB and histograms on JMP Pro 14 for each
case study abovementioned depending on several
operational environmental economic parameters.
The advanced and complex analysis procedures,
techniques and simulation tools (plant wide models)
supported perfectly the decision-making to meet a
sustainable self-efficient WWTP prototype. The
adopted algorithms, and calculation methods used to
generate models were all gathered in one user-
friendly interface or Software and detailed in PDD
submission. Different scenarios and treatment
configurations have been simulated and documented
by the CDM committee to illustrate the difficulty in
accounting for all constraints imposed on the
system. Therefore, the resulting model will serve as
a basis to target challenges that will set the scene for
determining directions of further developments
within the UNFCCC project delimitations. There are
also some tools within CDM methodology that
divide the carbon emission system of Fès sewage
treatment system into five aspects: material, energy,
material consumption, carbon sink and resource.
The focus of the CDM committee has been mainly
on CO2, CH4, and N2O GHG emissions factors.
The basic input referred to the baseline project on
which the additional improvement PDD submitted
to the CDM committee yet with further extension to
the data pool, energy balance components, energy
efficiency aspects and emissions factors. Using the
operation control method to determine the scope of
GHG assessment of the WWTP, the raw GHG
emissions must be 100% identified, and the
emissions related to sewage treatment must be
classified, as shown in Figure 12.
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
67
Volume 4, 2022
Figure 12: Assessment Scope Boundaries
The CO2, CH4, N2O and other GHG emitted by the
sewage treatment plant are uniformly measured by
the amount of CO2 produced. According to the
GWP, the potential value of CO2 is 1, and the
potential values of CH4 and N2O are 23 and 296
respectively, CH4 and N2O can be converted into
carbon emission equivalent according to the
corresponding potential values [6].
As per the IPCC agreement, it is the amount of CO2
directly emitted during sewage treatment. The CO2
emissions of biogenic wastewater are not included
in the total GHG emissions, according to the "GHG
Inventory Protocol-Corporate Accounting and
Reporting Standards" [6], the total GHG emissions
must be included. investigated and studied, the
amount of CO2 produced during the operation of the
actual sewage treatment plant, clarified to have the
following factors affecting CO2 emissions as per the
calculation formula of CO2 production:
MCO2 =Q*EFCO2 (1)
MCO2 - Biological treatment process emissions (g)
Q - Amount of sewage treated during calculation
(m3)
EFCO2 - emission factor to the CO2 emission of
the A2O process.
the calculation formula for CH4 generation is as
follows:
MCH4=(TOW*EFCH4)-R0 (2)
MCH4 - CH4 emissions from biological treatment
process (kg)
TOW - The organic matter content in sewage during
the calculation period (kg)
EFCH4 - CH4 emission factor to the methane
emission factor of the aerobic treatment process
R0 - The amount of CH4 recovered during the
calculation period (kg) if no sludge digestion R0 =0
The formula for calculating the amount of N2O
produced is as follows:
MN2O=TN*EFN2O (3)
MN2O - N2O emissions from biological treatment
process (kg)
TN - Total nitrogen removal from sewage during
calculation (kg)
EFN2O - N2O emission factor
During the operation of the sewage treatment plant,
blowers, pumps, aeration equipment and other
equipment consume a large amount of electricity,
the carbon emissions of the purchased electricity
during the production process are the indirect
emissions of the sewage treatment plant, the
calculation formula:
MCO2E=E*EFCO2E (4)
MCO2E - Indirect CO2 emissions from power
consumption (kg)
E - Power consumption (kWh)
EFCO2E - The emission factor of electric energy
consumption (kgCO2/kWh) Ref: Regional Grid
Baseline Emission Factor
Some chemicals are used in the sewage treatment
process, such as disinfectants, flocculants, etc., the
formula for calculating carbon emissions of
purchased chemicals:
MCO2Y=ΣYi*EFCO2Yi (5)
MCO2Y - Indirect CO2 emissions from chemicals
consumption (kg)
Yi - Consumption of chemicals i (kg)
EFCO2Yi - The emission factor of CO2
consumed by chemicals (kgCO2/kg)
Each used chemical should calculate its CO2
emissions with corresponding emission coefficients.
There are some other aspects of emissions, because
it is difficult to obtain GHG emission factors for
calculation, but should be estimated according to the
actual situation of the sewage treatment plant,
determine an appropriate ratio, and include it in the
total GHG emissions. After a comprehensive
analysis, it is determined that other emissions are
10% of the calculable emissions, which are included
in the total GHG emissions of the sewage treatment
plant.
A set of algorithms were formulated ruling GHGs
emissions during all phases and translated into
models to generate a user-friendly interface thesis
subject matter. Models generated present GHGs
emissions controlled and translated into the main
generic model to generate Software interface
literature subject matter.
4. Results and Further Improvements
In this literature, a cooperative decision support
system for energy saving and production in WWTPs
has been presented. The characteristics of this
decision support system are aligned with the
original research question and with the specific
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
68
Volume 4, 2022
objectives presented in the UNFCCC program,
CDM methodology, AM0080 project. The
comparison between the baseline project objectives
set by CDM and the obtained results using all
necessary simulations and modelling, was shared
step-by-step with the CDM committee and
preapproved before publication. The proposed
submission has been approved as a consistent model
and presented to committee with a coherent
structure enabling the integration of information,
data gathered online, static data, and expert
knowledge to provide decision making support
along with the advancement and technologies
adopted day by day in this field. Reaching the pre-
validation phase is sufficient to positively answer
the original and developed research questions.
4.2. Further Improvements
The set of Algorithms ruling GHGs emissions
during all treatment phases, translated into Bridge
Models to generate Final Model. The Final Model
gathered all bridge models into Loophole Basis
Control to assess all relevant projects via Software
Interface. Amount of CO2 directly emitted during
WWT according to the "GHG Inventory Protocol”
refers to equations (1), (2), (3), (4), & (5). GHGs
Emissions Reduction Final Equation collecting all
Variables & Parameters: PE_(EC,y)=
∑_j(EC_(PJ,j,y) × EF_(EF,j,y) ×(1+
TDL_(j,y)))
The data normalization of WWTP case study
consists of the new perspective for this research
where the application of a uniform set of
measurement units and the calculation of
comparable key performance indicators are the next
level of automation in WWTP management and
control strategy. This improvement, if ever
achieved, would make the calculations faster, more
stable and reliable, ultimately enabling the
connection of managing a larger number of WWTPs
with the same scale and conditions due course. An
original approach based on the random forest
algorithm was developed yet to be verified before
submission and integration. it is useful to mention
some of the forthcoming foreseen flaws and aims at
a time to stimulate a discussion within the
framework of this thesis knowing that these
shortages were the stimulus of Software further
development through continuous publications under
CDM mechanisms and sponsor upon publication:
application of software at larger scale, database
upscaling, IT & WWT mix of knowledge challenge
integrating core algorithms with fastest response,
central computed connectivity to electrical grid,
sewer mains database incorporation, widening the
application to more WWT typologies, and
commercial enhancement to interface.
5. Conclusions
This literature is the output of close follow up of
baseline plant despite the redundancy and time
salvage waiting committee response to proceed to
the next level along with potential failure in equity
with potential future developments identified and
approved. This study shows the possibility to build a
plant generic decision support system specifically
oriented to optimize the energy balance in WWTPs
and define GHGs emissions with remarkable
reduction on climate change grounds. The two main
lanes consist of ’market-oriented’ and ’research
oriented’ projects. The first lane is the development
of existing methodologies with the aim to deliver a
service to the market. The second lane consists of
the development of new methodologies for decision
making support. at the moment, it is possible to
report a strong interest from the UNFCCC and the
author to continue exploring the topic with new
projects and collaborations to assure the resulting
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
69
Volume 4, 2022
interface will be further extended to the flaws noted
hereabove, knowing that the current version of the
generated software delivers the required complete
report for an AAS WWTP energy balance, LCA,
LCC & GHGs emissions with suggestions and
recommendations for predesign or rehabilitation
enhancement based on solid decision making
support tools.
References:
[1] Clauson-Kaas, J., Poulsen, T. S., Jacobsen, B.
N., Guildal, T., & Wenzel, H. (2001).
Environmental accounting decision support
tool in WWTP operation. Water science and
technology, 44, 25–30.
[2] 2019 Energy Balances. United Nations
Publications (2021)
[3] Clean Development Mechanism - CDM
methodology UN Framework Convention on
Climate Change. (2013)
[4] Climate Change and Water - UN-Water Policy
Brief. UN Water. (2019)
[5] Climate change information kit. (1999). United
Nations Environment Programme
[6] Climate change MITIGATION - ISO14064
International Organization for Standardization
ISO. (2019)
[7] Cost Aspects of Wastewater Treatment United
Nations Environment Programme UNEP.
(2005)
[8] Groundwater Making the invisible visible
WWAP United Nations World Water
Assessment Programme (2021)
[9] Report on Susteainable Water and Energy
Solutions Addressing Climate Change United
Nations Department of Economic and Social
Affairs – UNESCO (2021)
[10] Sustainable Energy Management for WWT
Facilities U.S. Environmental Protection
Agency (2009)
[11] The Sustainable Development Goals Report
2021 United Nations SDG (2021)
[12] UN-Water analytical brief Water-use efficiency
UN Water (2021)
[13] UN-Water Annual Report 2020 UN Water
(2020)
[14] UN-Water Country Briefs Project UN Water
(2013)
[15] Wastewater The Untapped Resource United
Nations Educational, Scientific and Cultural
Organization – UNESCO (2017)
[16] Water and Energy UN World Water
Development Report 2014 WWAP - United
Nations World Water Assessment Programme
(2014)
[17] Emissions Gap Report 2021: The Heat is On
UNEP, UNEP Copenhagen Climate Centre
(UNEP-CCC) WWAP - United Nations
(October 2021)
[18] Kyoto Protocol to the United Nations
Framework Convention on Climate Change
COP3 Kyoto, Japan UNFCCC (December
1997)
[19] Forster, P., V. Ramaswamy Climate Change
2007: The Physical Science Basis Fourth
Assessment Report Intergovernmental Panel
on Climate Change Cambridge University
UK and USA (2007)
[20] Convention for the Protection of the
Mediterranean Sea Against pollution Official
Journal of the European Communities
Barcelona (1977 & 2004)
[21] Charikleia Prochaska, Nikolaos Stavropoulos
Review of Urban Wastewater Treatment in
Greece Laboratory of Chemical and
Environmental Technology (July 2020)
[22] Integrated National Energy and Climate Plan for
France The National Low-Carbon Strategy
Committee (March 2020)
Creative Commons Attribution License 4.0
(Attribution 4.0 International, CC BY 4.0)
This article is published under the terms of the Creative
Commons Attribution License 4.0
https://creativecommons.org/licenses/by/4.0/deed.en_US
Engineering World
DOI:10.37394/232025.2022.4.8
Firas Fayssal, Adel Mourtada, Mazen Ghandour, Remi Daou
E-ISSN: 2692-5079
70
Volume 4, 2022