Development and scale-up of technologies for wastewater tre-atment and reuse in Mediterranean African countries: the MADFORWATER
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Development and scale-up of
technologies for wastewater tre-
atment and reuse in Mediterranean
African countries: the MADFORWATER
project
Ed. by Roberta Lamaddalena and Dario Frascari
Contributors: ROBERTA LAMADDALENA, DARIO FRASCARI, NICO-
LAS KALOGERAKIS, STATHIS KYRIACOU, AHMED RASHED, ATEF
JAOUANI, AMEUR CHERIF, REDOUANE CHOUKR-ALLAH, SARA BO-
ALMA MATER STUDIORUM - UNIVERSITY OF BOLOGNA
RIN, CATHERINE GIBERT, JOCHEN FROEBRICH, NICOLA LAMADDA-
WATER RESEARCH INSTITUTE - NATIONAL COUNCIL OF
LENA, WEN-TAO LI, BRUNO MOLLE, CONSUELO VARELA ORTEGA,
RESEARCH BARI 2020 MARIJN MULDER, PHILIPPE CORVINI, MOHAMED ALHAMDI,
VITO FELICE URICCHIO
MADFORWATER - DEVELOPMENT AND APPLICATION OF INTEGRATED TECHNOLOGICAL AND MANAGE-
MENT SOLUTIONS FOR WASTEWATER TREATMENT AND EFFICIENT REUSE IN AGRICULTURE TAILORED
TO THE NEEDS OF MEDITERRANEAN AFRICAN COUNTRIES
Copyright to the Authors
This work is distributed under a Creative Commons - Attribution - 4.0 license https://creativecommons.org/licenses/
by/4.0/
Editors: Alma Mater Studiorum - University of Bologna, Bologna 2020 and Water Research Institute - National Council
of Research, Bari 2020
DOI: http://doi.org/10.6092/unibo/amsacta/6560.
ISBN: 9788854970380
Cite as: Lamaddalena R., Frascari D. (Eds.), Development and scale-up of technologies for wastewater
treatment and reuse in Mediterranean African countries: the MADFORWATER project, University of Bo-
logna, Bologna and Water Research Institute - National Council of Research, Bari, 2020. DOI: 10.6092/
unibo/amsacta/6560. ISBN: 9788854970380.
This project has received funding from the European Union’s Horizon 2020 research and innova-
tion programme under grant agreement No. 688320.
2
4 - An innovative approach for the treatment of fruit
Content and vegetable packaging wastewater.....................34
ABBREVIATION............................................................4 5 - A sustainable approach for the treatment and
1.INTRODUCTION........................................................5 valorization of Drainage Canal Water......................40
2.CURRENT SITUATION OF WASTEWATER TREAT- 7. IRRIGATION TECHNOLOGIES DEVELOPED BY THE
MENT, WASTEWATER REUSE, IRRIGATION, AND MADFORWATER PROJECT.......................................43
WATER MANAGEMENT IN EGYPT, MOROCCO, AND 1 - An efficient low-pressure anti-drift micro sprinkler
TUNISIA.......................................................................8 adapted to treated wastewater................................43
3. BACKGROUND INFORMATION ON THE MADFOR- 2 - An irrigation emitter resistant to clogging .........45
WATER PROJET...........................................................9 3 - A consolidated model to optimize irrigation with
4. GOALS AND CONCEPT..........................................10 water of different qualities.......................................47
5. THE CONSORTIUM................................................14 4 - Innovative biofertilizers for a sustainable agricul-
6. WASTEWATER TREATMENT TECHNOLOGIES ture in North African Countries................................49
DEVELOPED BY THE MADFORWATER PROJECT 5 - Increasing the efficiency of traditional surface
...................................................................................15 irrigation systems in Egypt.......................................51
1 - Innovative approaches for the treatment of muni- 8. THE MADFORWATER PILOT PLANTS OF INTE-
cipal wastewater.......................................................15 GRATED WASTEWATER TREATMENT AND AGRICUL-
2 - An innovative approach for the treament and va- TURAL REUSE............................................................52
lorization of olive mill wastewater...........................22
3 - Innovative treatment trains for the treatment of
textile wastewater.....................................................28
3
Abbreviations MENA = Middle East and North Africa
MPN = Most probable number (MPN)
MWW = Municipal Wastewater
BOD = Biological Oxygen Demand MWW = Municipal Wastewater
CHCW = Cascade Hybrid Constructed Wetland MWWTP = Municipal Wastewater Treatment Plant
COD = Chemical O demand NTK= Total Kjeldahl Nitrogen
CW = Constructed Wetland PGPB = Plant growth-promoting bacteria
CWP = Crop Water Productivity PP = Pilot Plant
DCW = Drainage Canal Water RDCW = Raw Drainage Canal Water
DM = Dry matter Semi-TDCW = Semi-Treated Drainage Canal Water
DO = Dissolved oxygen SHCW = Sequenced Hybrid Constructed Wetland
DU = Distribution Uniformity SIM = Safe Irrigation Management
EC = Electrical Conductivity SM = Suspended Matter
EU = European Union SP = Sampling Point
FAO = Food and Agriculture Organization TC = Total Coliforms
FBCW = Floating Bed Constructed Wetland TDCWT = Reated Drainage Canal Water
FC = Fecal Coliforms TMWW = Treated Municipal Wastewater
FDA = Fluoresceine Diacetate Hydrolysis Activity TN = Total Nitogen
FW = Fresh Water TOC = Total Organic Carbon
FWS = Free Water Surface TP = Total Phosphorus
GBSW = Gravel Bed Subsurface Wetland TSS = Total Suspended Solids
HCW = Hybrid Constructed Wetlands TTWW = Treated Textile Wastewater
HRT = Hydraulic Retention Time TWW = Textile Wastewater
M4W = MAD4WATER WP = Work Packages
MAC = Mediterranean African Countries WW = Wastewater
4
Introduction fields with — is incredibly rare. Only 3% of the world’s
water is freshwater, and two-thirds of that is tucked
away in frozen glaciers or otherwise unavailable for
Water is a vital resource, a primary element for our use. Two and a half billion people still lack ac-
humans and an essential source for the survival and cess to water sanitation facilities; 3 billion people are
development of any productive sector. It is a res- expected to suffer from water scarcity by 2050, and
ponsibility for everyone, as well as for institutions, to by 2030 a 40% gap is projected to develop between
defend, protect and preserve water as the essence sustainable water supplies and water withdrawals.
of life and the security for future generations. Hence An estimated 20% of the world’s aquifers are over-ex-
arises the modern setting of water management in ploited. The limit of sustainability in water abstraction
agriculture, based on stringent criteria of efficiency has been exceeded for about one-third of the human
and environmental protection, required also by the population. Eutrophication is expected to increase
EU and national legislation. The threat of climate almost everywhere until 2030. Climate change will
change, the effects of which have an impact on the exacerbate the water crisis, as a result of variations
water cycle and are particularly evident in the Medi- in the distribution and availability of water resources.
terranean area, requires an integrated approach to Agriculture is highly sensitive to water availability and
water management and policies. It is therefore quality, as it accounts for 70% of the world’s fresh-
necessary to ensure policies based on gover- water withdrawals. Agriculture faces the challenge
nance models compatible with various de- of producing 100% more food by 2050, but at the
mands of use, taking into account the trends same time the bio-economy will require an increased
of water consumption and availability. production of no-food agroproducts. The consequen-
Water covers 70% of our planet, and it is ces of water scarcity and poor quality are particularly
easy to think that it will always be plen- relevant in the Middle East and North Africa (MENA)
tiful. However freshwater - the stuff region.
we drink, bathe in, irrigate our farm
5
According to the Global Risk 2015 Report of the frequent power outages, low qualifica-
World Economic Forum, the water crisis represents tion of personnel, and undersizing
by far the greatest risk in the MENA region, where the of treatment plants. . In the MENA
expected population growth combined with econo- region, climate change is expec-
mic growth is projected to result in a 47% increase in ted to decrease precipitation
water demand by 2035. MENA is the driest region of and soil moisture and increase
the world, with water withdrawals exceeding renewa- evaporation from surface wa-
ble water resources by 30%. ters and crop water requirement.
These changes, combined with
The region is significantly affected by desertification, population growth, are expected
groundwater overexploitation, seawater intrusion into to decrease annual renewable water
aquifers, and water quality deterioration. In 2010, the resources to 414 m3 /capita by 2025. Among
annual renewable water resources in MENA coun- several possible strategies to fight the water crisis,
tries (525 m3 /capita, as an average) were about half the reuse of treated WW represents a promising and
the 1000 m3 /capita threshold for water scarcity and widely studied one: it provides a reliable supply of
just above the 500 m3 /capita threshold for absolute water during regional shortages, it enhances local
water scarcity. Water scarcity curbs socioeconomic economic growth, it reduces water withdrawal from
development, particularly in agriculture, which utilizes aquifers and rivers, it decreases fertilizer consump-
86% of water withdrawals in the MENA region. tion in agriculture, and it reduces eutrophication.
Unfortunately, few MENA countries implemented
The extent of wastewater (WW) treatment is still substantial WW reuse programs. Several internatio-
low in this region (43%, as an average). In addition, nal research projects aim to decrease water stress in
treated WW is typically characterized by insufficient the Mediterranean-African region.
removal of the main pollutants, due to lack of terti-
ary treatments, poor maintenance and monitoring,
6
water stress in the Mediterranean-African region. MADFORWATER developed and adapted to three
The MADFORWATER project aims to developing an main hydrological basins in the selected MACs
integrated set of technological and management technologies for the production of irrigation-quality
instruments for the enhancement of wastewater water from drainage canals, municipal, agro-indus-
treatment, treated wastewater reuse for irrigation, trial and industrial wastewaters, and technologies
and water efficiency in agriculture. MADFORWATER for water efficiency and reuse in agriculture, initially
focuses its activities on selected hydrological basins validated at laboratory scale. Selected technologies
located in 3 Mediterranean-African countries (MACs): were further adapted and validated in four field pilot
Egypt, Morocco, and Tunisia. These countries are plants of integrated wastewater treatment/reuse.
representative of the Mediterranean-African region Integrated strategies for wastewater treatment and
in relation to their population (74% of the region’s reuse targeted to the selected basins were develo-
inhabitants), GDP (64%), produced WW (88%), rate ped, and guidelines for the development of integrated
of WW treatment (50%), and hydrological characte- water management strategies in other basins of
ristics. The selected countries are characterized by a the three target MACs were produced, considering
relevant water scarcity: the annual renewable water climate change, population increase and economic
resources are equal to 60% of the of 1000 m3 /y growth scenarios. The social and technical suitability
threshold for water-stressed areas, and just 7% of the developed technologies and non-technologi-
of produced WW is currently reused. cal instruments in relation to the local context was
evaluated with the participation of MAC stakeholders
The aim of MADFORWATER was to develop and partners. Guidelines on economic instruments
a set of integrated technological and ma- and policies for the effective implementation of the
nagement solutions to enhance waste- proposed water management solutions in the target
water treatment, reuse for irrigation MACs were developed.
and water efficiency in agriculture
in Tunisia, Morocco and Egypt.
7
The MADFORWATER consortium consists of 17 Tertiary treatments are rarely imple-
partners, 5 of which from the North Africa and 1 from mented. The main technologies uti-
China. lized for secondary treatment are
activated sludge in Tunisia and
For further information on the project, visit the Egypt and lagoons in Morocco.
website: www.madforwater.eu or contact us: dario. The main operational problems
associated with WW treatment
in these countries include the
2. Current situation of wastewa- following: 1) insufficient aeration
in the secondary treatment, due to
ter treatment, wastewater reuse, power outages or excessive cost of
irrigation and water manage- energy; 2) strong delays and high costs for the
purchase of components for repairing equipment; 3)
ment in Egypt, Morcocco and failures of the secondary process due to the presen-
ce of toxic compounds carried by untreated indus-
Tunisia trial WWs; 4) WW treatment plants operating above
their capacity, due to rapid population growth; and 5)
In terms of WW treatment, the ratio of treated WW
insufficient monitoring of treated WW quality due to
to produced WW is equal to 57% in Egypt and 24% in
legal or technical constraints. The type and diffusion
Morocco, whereas a relatively advanced situation is
of irrigation technologies are quite diverse in the 3
observed in Tunisia, with a 79% ratio. In all 3 coun-
examined countries: in Egypt 98% of the cultivated
tries, a large fraction of the treated WW (75%–90%)
area is equipped with irrigation, whereas in Moroc-
undergoes secondary treatment for biological oxy-
co and Tunisia this fraction is equal to just 16% and
gen demand (BOD) removal, whereas the remaining
10%, respectively. Surface irrigation systems, such
fraction is subjected only to primary treatment.
as furrow, border strip, and basin irrigation, represent
8
the most common irrigation technology, with an for treated WW reuse. Each of the 3 target MACs
average efficiency equal to 60%. Conversely, loca- made significant progress in the field of sustainable
lized irrigation systems are not commonly used in water management in the last 2 decades. However,
these countries: drip irrigation (90% field efficiency) further advancement is needed to develop water
is used in 20% of the irrigated area (average of the 3 management strategies capable of 1) guiding local
countries), and sprinkler irrigation (75% efficiency) is governments, basin authorities, WWTP managers,
used in just 14% of the irrigated surface. Both Mo- and farmers in the selection of the most effective
rocco and Tunisia have significantly subsidized the water treatment and irrigation technologies, and 2)
supply of drip irrigation systems. However, because defining economic instruments aimed at enhancing
of poor maintenance and low equipment quality, the adoption of effective water treatment and irrigati-
most of these systems were clogged or inefficient on technologies and the reuse of treated WW. In all 3
after 1 to 2 y, and the farmers switched back to sur- countries, the national legislation imposes limits for
face irrigation. The treated WW reused for irrigation the agricultural reuse of treated WW.
is equal to 0.3% of WW produced in Morocco, 4% in
Egypt, and 24% in Tunisia. The fraction of the total
irrigation area equipped for irrigation with treated
3. Background information on
WW varies between 1% and 2%. The constraints the MADFORWATER project
leading to these poor levels of WW reuse are
lack of social acceptance due to inadequate Title: DevelopMent AnD application of integrated
information on the benefits of this practice technological and management solutions FOR
and to the poor monitoring of treated WW, wasteWATER treatment and efficient reuse in agricul-
incomplete economic analysis of WW ture tailored to the needs of Mediterranean African
reuse options, mismatch between Countries
water pricing and water scarcity, Acronym: MADFORWATER
and lack of economic incentives
9
Type: research and innovation project developed new technologies for water
efficiency and reuse in agriculture.
Project coordinator: Alma Mater Studorium – Uni- A tight collaboration with local
versità di Bologna players and stakeholders helped
Partners involved: 17 partners distributed over 6 EU to adequately tailor the proposed
countries, 3 selected Mediterranean African Coun- solutions to the local context.
tries (MACs), Switzerland and China The MADFORWATER project
aims at producing a relevant and
Funding: Horizon 2020 WATER-5c-2015
long-term impact in Egypt, Moroc-
Duration: June 1, 2016 - November 30, 2020 co and Tunisia in terms of wastewa-
The MADFORWATER project aims at achieving the ter treatment and reuse, thus improving
goals of the EU Horizon 2020 call for action topic agricultural production as well as decreasing
WATER-5c-2015, by focusing on the development of exploitation of water reserves and water pollution.
technological and non-technological solutions for the
management of water resources in Tunisia, Moroc- 4. Goals and concept
co and Egypt. The partners of the MADFORWATER
project are involved in developing and tailoring The general objective of MADFORWATER is to deve-
technological and management solutions focused on lop an integrated set of technological and manage-
wastewater treatment and efficient reuse in agricul- ment instruments for the enhancement of wastewa-
ture in North Africa. The new technologies developed, ter treatment, treated wastewater reuse for irrigation
that have been adapted to the social and technical and water efficiency in agriculture, with the final aim
context of the three countries involved, are aimed to reduce water vulnerability in selected basins in
at producing irrigation-quality water from municipal Egypt, Morocco and Tunisia. MADFORWATER tackled
and industrial wastewaters, as well as from draina- the integration of the supply (wastewater treatment)
ge canals. In parallel, the MADFORWATER project and demand (water reuse in agriculture) sides and
10the consequent adaptation of the proposed solutions sessment tool to be used for the evaluation of the
to the local context through: potential effectiveness of basin-scale water manage-
1. The installation and optimization of four field pilot ment strategies. 2) Developing and/or adapting to
plants of integrated wastewater treatment and effi- the local context technologies for WW treatment,
cient reuse in agriculture; treated WW reuse for irrigation, and efficient water
2. A participatory and multidisciplinary approach for use in agriculture. 3) Developing basin-scale water
the design of technologies and management solu- and land management strategies, closely related to
tions, attained by means of an international coope- the project’s technologies. 4) Increasing the level of
ration framework characterized by a consolidated capacity building in the target countries in relation to
collaboration between EU and Mediterranean African the proposed solutions and the social acceptance of
Countries (MAC) partners; treated WW reuse in agriculture. The achievement
3. A strong dialogue between the consortium and nu- of these MADFORWATER goals is based on 2 pillars:
merous MAC and international stakeholders involved WW treatment, selected as a valuable water source
in the Stakeholder Advisory Board, to maximize the for agriculture, and irrigation, which represents the
suitability of the proposed solutions in relation to the primary source of water demand in MACs. While the
local context, and therefore the expected long- term first pillar aims to increase the amount of available
impact of the MADFORWATER technologies, irrigation-quality water, the second aims to enhance
water management strategies and policies. WW reuse for irrigation and the efficiency of water
The overall goal of MADFORWATER was consumption in agriculture while also ensuring an
translated into the following specific objec- adequate soil health. These 2 pillars are transversally
tives: 1) Improving the identification of characterized by 2 key concepts: adaptation and inte-
vulnerabilities in terms of water quantity gration. A rigorous adaptation approach is applied to
and quality in Egypt, Morocco, and the development of technologies and management
Tunisia and developing a locally strategies for water and land in order to make them
adapted water vulnerability as- technically and culturally suitable for the environmen-
11mental and socioeconomic context of the target treatment and agricultural reuse; a
MACs. Such an approach includes the strong invol- high number of WW treatment and
vement of relevant MAC stakeholders who regularly irrigation technologies were inves-
provide feedback on the adaptation measures under- tigated separately at laboratory
taken and on the social acceptance of the proposed scale, in order to screen a large
solutions. In addition, integration is applied in the number of potential solutions
first place between the 2 pillars by means of a series and identify the most promising
of demonstration plants where different WW types ones in terms of performances,
are treated with MADFORWATER technologies and environmental impact, costs,
reused for the irrigation of crops typical of the 3 tar- benefits and adaptation to the local
get countries, using irrigation technologies adapted context; then, a selection of the WW
to the use of treated WW. The integration approach is treatment and water irrigation technologies
applied also within each MADFORWATER pillar, with were integrated in 4 field pilot plants, thus increasing
an integrated development of technologies, decision the scale for technology adaptation and integra-
support tools, and management strategies for water ting the water supply and water demand domains;
and land. • the implementation phase, which included activi-
ties to maximize the project’s long-term impact, such
MADFORWATER is articulated in 3 phases, or blocks as water and land management strategies, policy
of activities: recommendations, capacity building, and industrial
• the analytical phase, that produced tools for the exploitation.
analysis of water vulnerabilities related both to the
water supply and water demand domains at coun- This booklet focuses on the presentation of the main
try-scale and basin-scale; results attained by MADFORWATER in the frame-
• the technological phase, dedicated to the deve- work of the technological phase. In particular, sec-
lopment and adaptation of technologies for WW tion 6 presents the results of the development and
12adaptation of the WW and irrigation technologies at a. Olive mill WW (OMWW), containing high concen-
laboratory scale, whereas section 7 presents the re- trations of phenols (0.5-18 g/L) and COD (20-70 g/L),
sults achieved in the 4 pilot plants of integrated WW and characterized by a high production in the target
treatment and agricultural reuse. MACs: Tunisia 1.2‧106 m³/y, Morocco 3.5‧105 m³/y,
Egypt 1.4‧105 m³/y. Their high PC content (0.1-18
Four categories of WWs, selected on the basis of g/L) is toxic for plants. Thus, although OMWWs have
their quantitative and qualitative significance in the 3 traditionally been discharged directly in the olive tree
target MACs, were tackled in MADFORWATER, with fields, most countries have recently banned this prac-
the aim to produce irrigation-quality water, on the tice, thus imposing OMWW treatment.
basis of the following rationale: b. Fruit and vegetable packaging WW (FVPWW),
1. Municipal WW (MWW), that represents 82-92% produced in the packaging process of all the fruits
of the total produced WW in the studied MACs, and and vegetables exported by the target MACs. FVP-
which is characterized by a large untreated fraction. WW represents a concern mainly due to the rele-
2. Textile WW (TWW), chosen as a relevant type vant concentrations of different fungicides, mainly
of industrial WW, due to the significance and rapid thiabendazole (0.8-1.5 g/L), imazalil (0.25-0.5 g/L),
growth of the textile industry in the 3 target MACs guazatine (0.6-1.2 g/L) and ortho-phenyl phenol (1-
(textile production provides 6% of GDP in Egypt, 7% 1.2 g/L).
in Morocco and Tunisia). TWW production is equal 4. For Egypt MADFORWATER focused on drainage
to 48.106m³/y in Egypt, 2.8.106 m³/y in Tunisia and canal water (DCW), that collects most municipal and
2.7.106 m³/y in Morocco (5-7% of the total industrial industrial WWs produced in the Delta zone. It con-
WW produced in the target MACs). tains BOD (0.02-0.07 mg/L), COD (0.03-0.12 g/L), NH3
3. Two agro-industrial WWs have been selected on (0.01-0.03 g/L), heavy metals (Cu, Cr, Ba, Mn, Zn; up
the basis of their quantitative and qualitative relevan- to 0.01 g/L), fecal coliforms. 11‧109 m³/y of DCW are
ce in all the 3 MACs and of the lack of cost-effective, used for irrigation in Egypt.
industrial-scale processes for their treatment:
135. The consortium
The MADFORWATER consortium consists of 17 part-
ners geographically distributed mainly around the
Mediterranean Sea, in 7 European countries, 3 MACs,
and China. It comprises 9 universities, 4 research
centers, 1 international no profit organization (FAO), 1
consultant company with expertise in marketing and
business plan development, and 2 WW treatment
and irrigation companies that designed and con-
structed the MADFORWATER demonstration plants.
The expertise of the MADFORWATER partners are
listed in this table:
146. Wastewater treatment tech- low efficiency in removing ammonia nitrogen or
phosphorous. COD and BOD5 contents of the trea-
nologies developed by the ted municipal wastewater by the above mentioned
processes generally exceeds the limits imposed by
MADFORWATER project the local (e.g., NT 106.03) and ISO standards for the
1 - Innovative approaches for the treatment of mu- reuse of treated wastewater for irrigation. Moreover,
nicipal wastewater the microbiological content of the treated wastewa-
ter presents a health concern if it is used for irrigation
Main pollutants to be removed for an agricultural in agriculture.
reuse: Short presentation of the technologies developed
Organic compounds, nitrogen, phosphorous, TSS and by MADFORWATER for this wastewater
pathogens The challenge is to develop a treatment train able to
Technologies mainly used in Egypt, Morocco and attain high treatment efficiency and reliability, with
Tunisia for the treatment of this wastewater reduced capital, operation and maintenance costs.
Most of the municipal wastewater treatment plants MADFORWATER is developing one technique, which
located in Tunisia and Egypt use conventional consists in nitrifying trickling filters with innovative
aerobic activated sludge process (at low and high specific-surface carriers, for the secondary
medium loads) as secondary treatment. A treatment of municipal wastewater wastewater.
lower number of plants possess tertiary tre- As tertiary treatment, two techniques are tested: a)
atment for N and P removal with aerated constructed wetlands to remove N, P, heavy metals
lagoons. UV disinfection is used for the and emerging pollutants and b) Immobilized enzyme
tertiary treatment only at pilot scale bioreactors for the degradation of emerging pollu-
plants. The main disadvantage of tants. These technologies are briefly presented in the
the activated sludge process is the following tables.
15Nitrifying trickling filters with innovative high spe-
cific-surface carriers
Specific pollutants targeted by this technology:
Residual BOD, nitrogen, phosphorous, and pathogens
A trickling filter consists of permeable medium made
of a bed plastic (of rock or slag) over which wastewa-
ter is distributed to trickle through. It also includes a
distribution system. A rotary hydraulic distribution is
usually standard for this process.
This technology aims to:
- reduce retention times thanks to the attainment of a
high biofilm thickness,
- improve the nitrification / denitrification performan-
ces.
The lab scale reactor consisted of 4 compartments:
a septic tank for primary treatment of MWW, a
nitrifying trickling filter configured as a two-stage Lab scale reactor for municipal wastewater treatment
system (in the first stage, the removal of BOD is (1) Influent inlet, (2) Activated carbon filter, (3) Septic tank, (4) Recirculati-
accomplished, followed by the second stage where on tank, (5) Recirculating pump, (6) Water distributor, (7) 1st stage of the
nitrification is achieved), a recirculation tank, and a trickling filter, (8) 2nd stage of the trickling filter, (9) Secondary clarifier,
secondary clarifier for sludge settlement. (10) Effluent outlet
16Specific features that make this technology suita- ated under steady state conditions. Once the system ble for the context of Egypt, Tunisia and/or Moroc- stabilized, the reactor showed satisfactory organic co and for the attainment of the ISO 16075 stan- matter removal efficiency, since removal rates of 91 dard for agricultural WW reuse and 92% were achieved for COD and BOD, respecti- Trickling filters may be suitable for the target coun- vely. The resulted COD and BOD concentrations are tries thanks to the low maintenance, cheap installati- in the range of the limits imposed by the Tunisian on and high stability against fluctuation of hydraulic Standard NT106.03 for wastewater reuse in irrigation and organic loads. The operation of a trickling filter (COD
standard NT 106.03 in terms of TSS (30 mg/L). Constructed wetlands
The effluent pH data fluctuated between 7.13 and Specific pollutants targeted by
7.62, and achieved the Tunisian standard specifica- this technology:
tion value of 6.5–8.5. The average EC value of the Heavy metals, HMs (Ni, Cd, Zn)
effluent was 7.2 mS/cm, which was similar to that and emerging organic conta-
observed for the affluent (7.8 mS/cm). The resulted minants (EOCs) (bisphenol A,
EC values exceed slightly the allowable Tunisian ciprofloxacin, sulfamethoxazole)
standard NT106.03 specification of 7 mS/cm.
Specific obstacles relative to the application of this Technology description
technology in Egypt, Tunisia and/or Morocco and to CWs for wastewater treatment involve
the production of irrigation-quality treated waste- the use of engineered systems that are designed
water according to the ISO 16075 standard (max 5 and constructed to utilize natural processes. These
lines) systems are designed to mimic natural wetland sys-
The average values of the main physicochemical tems, utilizing wetland vegetation, soil, and associa-
characteristics of the treated municipal wastewater ted microorganisms to remove contaminants from
were comparable to those specified by the Tunisian wastewater effluents. They can achieve multiple
standard NT106-03 for wastewater reuse in irrigation goals of contaminant removal such as total sus-
and the new Tunisian regulation published in 2018 pended solids, biochemical oxygen demand, organic
(Official Journal of the Tunisian Republic) except for compounds, and inorganic constituents to meet
phosphorous and faecal coliform. This technology regulatory targets. Horizontal subsurface flow CW
is considered as secondary treatment and a part of mesocosms made from stainless steel, filled with
tertiary treatment. Further treatments for pathogen gravel and planted with the Mediterranean haloplyte
removal should be integrated. Juncus acutus L. is fed with municipal wastewater
18polluted with heavy metals and emerging organic Specific features that make this technology suita-
contaminants. Specific bacteria inoculants endowed ble for the context of Egypt, Tunisia and/or Moroc-
with degrading potential and the ability to promote co and for the attainment of the ISO 16075 stan-
plant growth can be used to reclaim water in the dard for agricultural WW reuse
so-called ‘microbial assisted phytodepuration’, ma- Constructed wetlands are low cost, low-energy, easily
king the study of CW plant-associated microbiome a operated and maintained compared to conventional
priority to gain advanced and exploitable knowledge. treatment systems, able to achieve contaminants re-
movals to meet regulatory targets and have a strong
potential for application in developing countries,
particularly by small rural communities. Moreover,
as selection of the appropriate plant species is an
important efficiency parameter and meditereannean
halophytes are proven to be ideal candidates.
Results obtained in MADFORWATER
With influent municipal wastewater heavy metals
concentrations up to twice the limits for WW reuse
for irrigation, CWs means removal capacities up to
99% for Cd, 51% for Ni and 45% Zn are noted. With
influent concentrations of emerging organic contami-
Representation of the horizontal subsurface flow nants 100μg/L of bisphenol A (BPA), 1mg/L of ciprof-
system, for the treatment of municipal wastewater loxacin (CIP) and 5 mg/L of sulfamethoxazole (SXS),
contaminated with EOCs/HMs. CWs means removal efficiency up to 76% for BPA,
94% for CIP and 27% for SXS are recorded. These
19results have been obtained without the effect of plant Constructed wetlands
growth promoting bacteria on the overall efficiency
Specific pollutants targeted by
of the process.
Pharmaceuticals, organic micro-
pollutants
Technology description
This technology utilizes laccases
immobilized onto resin particles
with a low pressure drop in a packed
bed reactor fed with a continuous flow
of wastewater. Laccases have been selected since
they can catalyze the oxidation of a wide range of
Cd concentration in the constructed wetland influent and effluent
phenolic and nonphenolic lignin-related compounds,
including many pharmaceuticals and micropollutants
Specific obstacles relative to the application of this commonly occurring in municipal WW and typically
technology in Egypt, Tunisia and/or Morocco and to not degraded in conventional municipal WWTP, they
the production of irrigation-quality treated waste- can be relatively simply isolated and purified from
water according to the ISO 16075 standard (max 5 white rot fungi. Besides allowing continuous ope-
lines) ration, immobilization on solid supports has been
demonstrated to enhance enzyme stability.
None.
Packed bed column
with immobilized
enzymes
20Specific features that make this technology suita- carriers was observed in preliminary tests, hampe-
ble for the context of Egypt, Tunisia and/or Moroc- ring quantification of the pollutants degradation.
co and for the attainment of the ISO 16075 stan-
dard for agricultural WW reuse Concentrations of pharmaceuticals in real municipal
wastewater samples from Tunisia and Morocco
The packed bed reactor is easy to operate, does not
require sophisticated instrumentation, regulation or
high pressure pumps and it could be more suitable
compared to other reactor configurations, such as
membrane reactors, for wastewater treatment in
African countries.
Results obtained in MADFORWATER
Laccases from P. sanguineus (L1) and T. versicolor
(L2) were immobilized onto resin particles or fumed
silica nanoparticles (fsNP) and tested in a batch re-
actor on spiked municipal wastewater (500ng/L
of each compound). The most efficient laccase
(from P. sanguineus) removed 7-83% of the
pharmaceuticals after 5 days. Treatment of
the real municipal wastewater was perfor-
med with the laccase from P. sanguineus
in a packed bed reactor with a conti-
nuous flow rate. Adsorption of the
micropollutants onto the enzyme
21Specific obstacles relative to the application of this environment, with the unfortunate side
technology in Egypt, Tunisia and/or Morocco and to effect of severe odor emission. This
the production of irrigation-quality treated waste- is caused by the flotation of residu-
water according to the ISO 16075 standard al oily substances in the OMWW,
This technology is considered as tertiary treatment. inhibiting evaporation and crea-
Primary treatment and secondary biological treat- ting anaerobic conditions. Odors
ment should be integrated. Costs of enzymes and are the main disadvantage of
resin used for immobilization are relatively high. evaporation ponds, especially for
those operating near domestic
areas.
2 - An innovative approach for the treatment and
valorization of olive mill wastewater Short presentation of the technologies
developed by MADFORWATER for this wastewater:
Main pollutants to be removed for an agricultural MADFORWATER is developing two alternative treat-
reuse ment trains for OMWW: the first one is articulated in
Organic compounds (COD 20-100 g/L); polyphenols suspended solids removal by microfiltration, polyp-
(1-10 g/L) henol recovery from the filtrate by adsorption and
Technologies mainly used in Egypt, Morocco and final BOD removal by biomethanation; the second
Tunisia for the treatment of this wastewater: (max one consists in an aerobic biological treatment in a
8 lines) sequenced batch reactor with lime addition. These
technologies are briefly presented in the following
According to Tunisian legislation, the main practice to
tables.
manage olive mill wastewater (OMWW) is to dischar-
ge it into evaporation ponds. This treatment process
aims to reduce the impact of OMWW on the environ-
22MICROFILTRATION AND POLYP-
HENOL RECOVERY BY ADSORPTION
Specific pollutants targeted by this technology:
Suspended solids and polyphenols
Technology description
An initial microfiltration step, aimed at the removal of
suspended solids, is followed by an adsorption / des-
orption step aimed at the recovery of polyphenols.
This leads to the production of i) a polyphenol-rich
mixture that, thanks to its high antioxidant capacity,
can find application in several industrial processes Specific features that make this technology suita-
or products formulation and ii) a dephenolized water ble for the context of Egypt, Tunisia and/or Moroc-
that can be treated biologically more efficiently. co and for the attainment of the ISO 16075 stan-
Two columns operate in parallel: while the first one dard for agricultural WW reuse
adsorbs polyphenol from olive mill wastewater, the
second desorbs the antioxidants collected during This technology is suitable for the North African con-
the previous cycle. The desorption solvent (typically text thanks to its capacity to produce an antioxidant
ethanol) is entirely recycled within the process by mixture that can potentially have a relevant market
evaporation and re-condensation. value. At the same time, the removal of polyphenols
from olive mill wastewater is important in order to
Pilot plants for the microfiltration and adsorption of olive avoid any potential crop damage associated to the
mill wastewater antioxidant and antimicrobial activity of these com-
pounds.
23Results obtained in MADFORWATER relatively to Specific obstacles relative to the
this technology application of this technology in
The removal of suspended solids by filtration was Egypt, Tunisia and/or Morocco
very high (98%) and characterized by a limited, and to the production of irriga-
acceptable loss in polyphenols (9%) with the solids. tion-quality treated wastewater
Different types of resins were tested for the polyp- according to the ISO 16075
henol recovery step from the water phase. A neutral standard (max 5 lines)
adsorption resin (XAD 16) was selected as the most • In order to produce an irrigati-
effective one. It leads to the recovery of a polyphenol on-quality water, the proposed tech-
mixture characterized by a very high antioxidant nology must be integrated by a treat-
capacity. Polyphenol removal is equal to about 90%, ment step aimed at the biodegradation of
leading to a residual polyphenol concentration in the organic compounds (e.g., anaerobic digestion).
treated effluent equal to about 0.1 g/L. • The operation of the proposed technology requires
personnel with adequate technical skills, capable to
Polyphenol outlet concentration versus time in the outlet of an
manage adsorption, evaporation and condensation
adsorption test. Experimental data and best-fitting simulation
processes.
• Some safety issues are related to the need to stock
ethanol. Local legislation on safety in workplaces
must be carefully applied.
ANAEROBIC DIGESTION
Specific pollutants targeted by this technology:
Organic matter
24Technology description Specific features that make this technology suita-
Biodegradable organic compounds (BOD) are con- ble for the context of Egypt, Tunisia and/or Moroc-
verted into methane and carbon dioxide thanks to co and for the attainment of the ISO 16075 stan-
the combined action of acidogenic and methanoge- dard for agricultural WW reuse
nic microorganisms. The process is operated under Anaerobic digestion is characterized by a medi-
anaerobic conditions at 35-40 °C in a stirred reactor. um-low level of technical complexity and by a null
Dephenolized olive mill wastewater can be co-di- energy consumption. On the other hand, it leads to
gested in combination with other agricultural wastes. the production of electrical energy that can be sold
The produced biogas is typically burned, leading to a to the local energy grid. The production of irrigati-
combined production of heat and electrical energy. on-quality water requires a high retention time for the
complete removal of BOD, and a further treatment
Anaerobic digestion pilot plant step for solid / liquid separation (for example, a fil-
ter-press). The solid digestate produced can be used
as a fertilizer.
Results obtained in MADFORWATER
The results indicate that olive mill wastewater is a
good candidate for the anaerobic digestion process,
with a relatively high yield of methane production
(260-400 NLCH4/kgVolatile Solids) and an acceptable
methane production rate (110-200 LCH4/m³digesta-
te/d). Previous olive mill wastewater dephenolization
leads to a 30-40% incerase of the process perfor-
mances. The tests aimed at evaluating the capacity
of the process to attain the low BOD concentrations
25centrations required by the ISO standards for water AEROBIC BIOLOGICAL TREATMENT
reuse in agriculture (< 100 mg/L) are still in progress. IN A SEQUENCED BATCH REAC-
TOR
Specific pollutants targeted by
Organic compounds, Phenolics
Technology description (max 8
lines + 1 picture + 1 flow sheet)
Sequenced Batch Reactors (SBR)
are a special form of activated sludge
treatment in which the whole
treatment process takes place in the reactor tank
and clarifiers are not required. This process treats
the wastewater in batch mode and each batch is
sequenced through a series of 5 treatment stages: 1.
Fill; 2. React; 3. Settle; 4. Decant and 5. Idle.
Methane production yield obtained with dephenolized and
non-dephenolized OMWW
Specific pollutants targeted by this technology:
Anaerobic digestion of olive mille wastewater is
considered suitable for the specific context of Egypt, SBR operating
Morocco and Tunisia. principle
26First, the tank is filled by the OMWW. During the pital costs. Moreover, it allowed the establish-
second stage, mixing is provided by mechanical ment of a stable microbial population, capable of
means and aeration of the mixed liquor is performed degrading potentially toxic compounds. The ad-
via diffusers fixed to the floor of the tank. No aeration dition of pulverulent lime permits further removal
and mixing are provided in the third stage to settle of COD and phenolics by both coagulation and
the suspended solids. During the fourth stage the adsorption phenomena.
OMWW treated supernatant is recovered. In the fifth
stage the excess sludge is removed. Results obtained in MADFORWATER
The SBR reactor was seeded with a sample of acti-
The treated wastewater is then subject to lime additi- vated sludge from a municipal wastewater treatment
on under pulverulent form (CaO) until pH 12. plant, which was stepwise acclimatized towards the
high COD content present in the OMWW by operating
Specific features that make this technology suita- the reactor for several sequenced batches with a hy-
ble for the context of Egypt, Tunisia and/or Moroc- draulic retention time of 30 days each and increasing
co and for the attainment of the ISO 16075 stan- COD concentrations in the influent OMWW up to 75
dard for agricultural WW reuse g L¯¹. Similar COD reduction efficiencies (about 60%)
have been achieved after each sequenced batch with
Sequencing batch reactor (SBR) could be applied for a stable removal rate of 1.5 gCOD L¯¹ D¯¹, indicating
nutrients removal, high biochemical oxygen demand the presence of a stable microbial consortium. The
containing industrial wastewater, wastewater contai- combination of biological treatment to pulverulent
ning toxic materials such as cyanide, copper, chromi- lime addition allowed the removal of up to 80% and
um, lead and nickel, food industries effluents, landfill 90% of COD and phenolics respectively. However, the
leachates and tannery wastewater. Of the process COD of the treated OMWW still exceeds the stan-
advantages are single-tank configuration, small foot dards for irrigation water indicated in ISO and Tunisi-
print, easily expandable, simple operation and low ca- an standards (NT 106.03).
273 - Innovative treatment trains for
the treatment of textile wastewater
Main pollutants to be removed
for an agricultural reuse:
Azo dyes, sulfonated azo dyes
Technologies mainly used in
Egypt, Morocco and Tunisia for
the treatment of this wastewater
The current situation of textile was-
tewater (TWW) treatment in these three
Stepwise acclimatization of the aerobic consortium to high countries is quite diverse. Some textile companies
OMWW concentrations in a SBR from have already integrated internal wastewater
treatment processes into their process sequences,
Specific obstacles relative to the application of this aiming to reach up to 60% reintegration of the se-
technology in Egypt, Tunisia and/or Morocco and to wage into the processes. The remaining treated
the production of irrigation-quality treated waste- wastewater is discharged into the municipal sewage
water according to the ISO 16075 standard network. Coagulation is a widely applied process as
This technology is suitable for the specific context of a pre-treatment prior to principal treatment by acti-
Egypt, Morocco and Tunisia. No specific obstacles vated sludge, oxidation or membranes. Coagulation
are reported in relation to the production of irrigati- aims to remove colloidal particulates and organic
on-quality treated wastewater. However, additional substances. The efficiency of the current processes
dilution or treatment is required in order to further is generally instable in relation to the important daily
reduce the remaining COD concentration. and seasonal variation of effluents volume and of
28organic and mineral load. An adequate process able Specific pollutants targeted by this technology:
to tolerate occasional peaks of effluent volume and The wastewater contaminated with toxic dyes is
organic load must be used. In some cases, textile pumped into the first mixing tank with a peristaltic
effluents are discharged directly into the municipal pump where coagulants - flocculants are added and
sweage network without any pre-treatment. then it overflows to the primary clarifier for precipita-
tion of suspended particles. The supernatant waste-
Short presentation of the technologies developed water from this tank flows to the tank with carriers
by MADFORWATER for this wastewater (ΜΒΒR), where biological degradation occurs. An
MADFORWATER is developing a secondary tre- aerator provides oxygen to the water and fluidize
atment process in moving bed biological reactor biofilm carriers. The sludge is allowed to settle in
(MBBR) to be applied downstream a coagulation/ the secondary clarifier tank which follows, while the
flocculation step, in order to degrade COD and azody- effluent from this tank is recirculated through a peris-
es, and two alternative tertiary treatment processes taltic pump to the biodegradation tank (MBBR). The
aimed at removing the residual dyes, namely i) dyes system was operated as a batch reactor, since only
enzymatic degradation in packed bed reactors with the MBBR reactor and the secondary clarifier tank
immobilized laccases and, ii) dyes adsorption/ were operated by recirculation.
desorption with innovative magnetic resins. Laboratory scale plant
These technologies are briefly presented in the for the treatment
of textile WW in a
moving bed biological
Moving Bed Biological Reactor reactor (MBBR)
Specific pollutants targeted by this
Toxic azodyes
29Specific features that make this technology suita- irrigation (ISO 16075-1-2015) which are 30 for am-
ble for a MAC context and for the attainment of the monium nitrogen, 35 for total nitrogen and 7mg/l for
international standards for agricultural WW reuse total phosphorous the treated TWW can be used for
This technology has proven effective in the biode- irrigation.
gradation of dyes whose presence in textile waste-
waters has been identified as a critical issue for their
reuse in irrigation.
Results obtained in MADFORWATER
MBBR was fed with synthetic wastewater supple-
mented with 0.08 to 0.48 g L¯¹ dye concentrations.
These concentrations are typically obtained after
primary treatment with coagulants. An efficient
consortium isolated from marine environment was
inoculated to the system, developing the biomass on
freely moving carriers. The decolorization efficiency
of the system was above 80% for all tested dyes after
Dyes removal from textile WW in the moving bed biological
95 days operational period. Ammonium nitrogen,
reactor (MBBR)
total nitrogen and total phosphorous were measu-
red 1.2, 35 and 2.7 mg/l respectively. According to Specific obstacles relative to the application of this
the maximum levels of nutrients in TWW used for technology in a MAC context and to the production
irrigation (ISO 16075-1-2015) which are 30 for am- of irrigation-quality treated WW
monium nitrogen, 35 for total nitrogen and 7mg/l for Overall, there should be no problem in the application
total phosphorous the treated TWW can be used for of the MBBR technology; however, care should be
30no problem in the application of the MBBR techno-
Lab-scale bioreactor for dye
logy; however, care should be taken of the sludge
removal with immobilized
removal from the primary step. If the quantities are
enzymes
small (when expensive coagulants are used) simple
drying and disposal should be OK. In the case whe-
re lime is used, the amount of watery sludge being
produced is very high (almost 30 to 50% of the initial
wastewater volume) and a specific treatment techno-
logy for this must be considered.
Moving Bed Biological Reactor
Specific pollutants targeted by this technology:
Specific features that make this technology suita-
Azo dyes, sulfonated azo dyes
ble for the context of Egypt, Tunisia and/or Moroc-
Specific pollutants targeted by this technology: co and for the attainment of the ISO 16075 stan-
dard for agricultural WW reuse
Laccases and peroxidases are known enzymes with
The packed bed reactor is easy to operate, does not
ability to decolorize various types of dyes. This
require sophisticated instrumentation, regulation or
technology is utilizing immobilized enzymes in
high pressure pumps and it could be more suitable
packed bed reactor to treat textile wastewa-
compared to other reactor types using immobilized
ter. Immobilization of the enzymes usually
enzymes, such as membrane reactors, for wastewa-
improves enzyme stability. Resin par-
ter treatment in African countries.
ticles (100-300µm size) were used as
enzyme carriers and the packed bed
Results obtained in MADFORWATER
reactor is operated at continuous
flow rate. Six sulfonated azo dyes have been selected as the
31the main contaminants of the real textile wastewater.
Laccases from the fungi P. sanguineus and T. ver-
sicolor were able to decolorize two out of six dyes.
Dye-decolorizing peroxidase did not remove any of
the dyes and horseradish peroxidase degraded only
one dye. Redox mediators enable laccase to oxidize
more compounds. The oxidation step is performed
by the oxidised form of the mediator, generated on its
interaction with laccase. Three different redox medi-
ators have been tested and 1mM 1-hydroxybenzot-
riazole showed the highest extent of decolorization. Decolourization of dyes Bezaktiv Bleu S-Matrix 150 and Be-
Partial decolorization was observed in the real textile zaktiv Bleu S-2G by laccases, as indicated by the reduction
wastewater that was spiked by six dyes and treated of absorbance at 600 nm.
by laccase from T. versicolor. In experiments perfor-
Specific obstacles relative to the application of this
med with immobilized laccases, dyes adsorption of
technology in Egypt, Tunisia and/or Morocco and to
the enzyme carrier mainly occurred, with negligible
the production of irrigation-quality treated waste-
dyes degradation.
water according to the ISO 16075 standard
This technology is highly dependent on quality of the
textile wastewater. Enzymes are not able to decolori-
ze a big range of structurally different dyes and if the
composition of the wastewater significantly fluctuate
this technology may become inefficient. Negatively
charged dyes are adsorbed by the enzyme carriers.
Costs of enzymes and resin used for immobilization
32are relatively high.
Adsorption on innovative resins
Specific pollutants targeted by this technology:
Dyes and dissolved organic matter
Specific pollutants targeted by this technology:
The magnetic anion exchange resin (MAER) develo-
ped by Nanjing University, China is designed specifi-
cally to remove organic matter and negative-charged
dyes from water and wastewater. The MAER has
The magnetic anion exchange resin and the fluidized-bed
a polyacrylic matrix, a macroporous structure and
reactor
strong-base functional groups. The resin beads have
a diameter of 100-200 um, which has high surface Specific features that make this technology suita-
area and mass transfer rate than the convention ble for the context of Egypt, Tunisia and/or Moroc-
resins. The MAER is used in suspended manner co and for the attainment of the ISO 16075 stan-
in a completed mixed flow reactor. The mag- dard for agricultural WW reuse
netic core aids agglomeration and settling of The MAER has fast and good treatment capacity for
the resin. The MAER can be regenerated by removal of most negative-charged organic matter
10% NaCl solution and the reactor utilize and dyes. However, the usage of NaCl and the treat-
a side-stream, continuous regeneration ment of the brine wastewater from resin regeneration
process allowing for a consistent trea- process limits it large application. The textile factory
ted water quality. About 200~300 m³ in these countries usually generates ~200 m³ waste-
wastewater generates 1 m³ brine water per day, which means ~ 1 m³ brine wastewater
wastewater.
33stewater is produced every day. The price of NaCl is The synthesis for the permanent-magnetic anion exchange
cheap and the brine wastewater can be easily evapo- resin (MAER) and its adsorption capacity to the dye Oran-
rated according to local drought climate. ge-G in comparison with the commercial MIEX and IRA-900
anion exchange resin
Results obtained in MADFORWATER
A novel permanent-magnetic anion exchange resin Specific obstacles relative to the application of this
MAER was developed by use of diallyl itaconate (DAI) technology in Egypt, Tunisia and/or Morocco and to
as the crosslinker, which significantly improved the the production of irrigation-quality treated waste-
hydrophilicity, strength and adsorption capacity. The water according to the ISO 16075 standard
dye-saturated MAERs can be efficiently regenerated The anion exchange resins cannot remove those
by a mixture of NaCl/NaOH solution (10%/1%). Du- fibers, organic matter or dyes which are not negati-
ring 20 cycles, the MAER could be reused without a vely-charged in textile wastewater. This technology
noticeable decline in adsorption capacity for the dye must comply with the other wastewater treatment
Orange-G, indicating a superior anti-fouling perfor- technologies.
mance for removal of organic matter. Taken together,
the high capacity, fast kinetics, excellent reusability 4 - An innovative approach for the treatment
and convenient separability of MAER made it a good of fruit and vegetable packaging wastewater
candidate for organic matter removal.
Main pollutants to be removed for an agricultural
reuse:
Organics (COD), suspended solids, fungicides
Technologies mainly used in Egypt, Morocco and
Tunisia for the treatment of this wastewater: (max
8 lines)
34Depending on local conditions, different treatment Dissolved and colloidal organic contaminants
options are currently used for wastewaters from
fruit and vegetable packaging, such as septic tanks, Technology description
aerobic lagoons or activated sludge. These treatment The technology is based on the use of small plastic
technologies are capable of removing part of the cri- carrier elements with density similar to water, which
tical contaminants (persistent organics, suspended are colonized by microorganisms in the form of a
solids and fungicides), but the resulting effluent qua- biofilm. The carriers are mixed with wastewater in an
lity is low with respect to the reuse standards. aerated tank and the microorganisms remove degra-
dable organic matter from the wastewater. Aeration
Short presentation of the technologies developed of the bioreactor serves for mixing and supply of oxy-
by MADFORWATER for this wastewater: (5 lines) gen to the microorganisms. The needed contact time
To achieve high quality effluent which can meet for the specific wastewater is between1 and 4 days,
reuse standards, a treatment train combining diffe- depending on the initial concentration of the fungici-
rent technologies was designed: Moving bed biofilm des. Subsequently, the treated wastewater is remo-
reactor (MBBR) to remove organic contaminants and ved from the bioreactor, whereas the carriers are
fungicides, Integrated flotation and flocculation to retained inside by a sieve. The biological processes
efficiently remove suspended solids and UV-Oxi- generate certain amount of excess biomass, which is
dation/Immobilised enzymes to remove resi- separated in the subsequent flocculation and dissol-
dual fungicides. As an alternative to the last ved air flotation (DAF) step, together with the sus-
technology, sorption on activated carbon pended solids originating from the wastewater.
can be applied for the fungicide removal.
MBBR carriers with develop-
Aerobic moving bed bioreactor ped biofilm
Specific pollutants targeted by
this technology:
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