INDEX LANDFILL LEACHATE TREATMENT BY CONSTRUCTED WETLAND FOCUSING ON ORGANIC MATTER AND NITROGEN REMOVAL Vitor Cano

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1 INDEX Page Title 1-31 LANDFILL LEACHATE TREATMENT BY CONSTRUCTED WETLAND FOCUSING ON ORGANIC MATTER AND NITROGEN REMOVAL Vitor Cano EXCELLENCE CENTER FOR DEVELOPMENT COOPERATION Ngandjui Tchangoue, Yvan Anderson

2 LANDFILL LEACHATE TREATMENT BY CONSTRUCTED WETLAND FOCUSING ON ORGANIC MATTER AND NITROGEN REMOVAL Vitor Cano PhD Graduate Program in Sustainability Dr. Marcelo A. Nolasco Advisor UNIVERSITY OF SÃO PAULO BRAZIL

3 Introduction Brazil: 2010 National Policy on Solid Waste No generation Reduction Reuse Recycling Closure of existing open dumps Implementation of sanitary landfills System integration (recycling and composting)

4 Introduction Environmental liabilities historically caused by landfilling: Leachate Leachate Source: Farquhar (1989) Humic/fulvic acids Xenobiotics Organochlorine Ammonia nitrogen Toxic metals Others Source: own author LC50 (48 h) between 2.2 to 5.7% (v/v) (Sisinno, 2002)

5 Introduction Source: Farquhar (1989) Figure Leachate compounds concentration over time Landfill leachate characteristics Parameter Range 1 Most Frequent 2 ph COD (g.l -1 ) BOD (mg.l -1 ) 150 9,660 <20 8,600 NH 4 -N (mg.l -1 ) 162 1, ,800 NO 3 (mg.l -1 ) Fonts: Ferreira et al. (2001), Silva (2002), Fleck (2003), Lange et al. (2006), Morais et al. (2006), Bidone (2007), Contrera (2008), Costa et al. (2013); 2 Fontes: adaptado de Lange e Amaral (2009) e Souto (2009). OM and N / Variable composition / Toxicity

6 Introduction Landfills in Sao Paulo Leachate Municipal Wastewater Treatment Plant: Co-treatment with domestic wastewater Sludge produced during treatment

7 Introduction There is no clearly defined solution to the treatment of landfill leachate (Abbas et al., 2009) Sustainable low-cost alternative: Constructed Wetlands

8 Constructed Wetlands Systems designed and constructed to utilize natural processes to remove pollutants from contaminated water within a more controlled environment (Wu et al., 2014). Vymazal (2009) Construction, operation and energy consumption: low cost

9 Constructed Wetlands 8 Operation strategies Oxygen diffused into the system Constructed wetland performance improvement (Lavrova, 2016). (Aeration = energy consumption higher cost)

10 Materials and method Lab. scale experiment at University of Sao Paulo Landfill leachate Guarulhos city Municipal Landfill (Sao Paulo Metropolitan Region ) 13 years of operation Pre-treatment Air stripping (HRT 3 days) Dillution (tap water): 30% Micro-nutrients addition (Germirli et al., 1991)

11 Materials and method Table Landfill leachate characteristics after pre-treatment Parameter mg.l -1 (mean ± SD) Chemical Oxygen Demand 691 ± 129 Total organic carbon 271 ± 73 Inorganic carbon 198 ± 28 Ammonium nitrogen 161 ± 58 Total nitrogen 228 ± 87 Nitrate 3 ± 3 True color* 1010 ± 425 Apparent color* 1480 ± 562 Turbidity** 41 ± 18 *unit: mg PtCo.L -1 **unit: NTU

12 Materials and method Subsurface Horizontal Flow Constructed Wetland Unit Surface (m²) 0.22 Total Volume (L) 30.5 Net Volume (L) 10.7 Fonte: Próprio Autor 11

13 Materials and method Heliconia psittacorum Density: 14 seedlings/m ² Substrate Diameter (mm) 5 Porosity (%) 48.6

14 Materials and method Sequential Constructed wetland system: Feeding tank; Two sequential HF-CW units; Effluent tank. Control without plants

15 Materials and method Operational Phase 1 Phase 2 Parameters (n=16) (n=26) Unit Flow 2.6±0.2 2,5±0,8 L.d -1 HRT 8.1±0.7 9,9±3 d Duration d Leachate % ph adjustment No Yes (7.5) -

16 Results and discussion Organic Matter

17 Results and discussion Units A ( ) and B ( ) contribution for global COD removal efficiency Global removal efficiencies Control: 6% HP: 14% Global removal efficiencies Control: 18% HP: 20%

18 Results and discussion Organic matter: phase 1 x phase 2 Treatment methods that chemically modify leachate may cause unexpected changes in its toxicity (Marttinen et al., 2002 ). ph adjustment Ammonia Nitrogen Organic compounds Other compounds

19 Results and discussion Organic matter Low removal efficiency No response of nutrients and HRT Recalcitrance of organic contaminants was reported as an important limitation for COD removal (Vymazal, 2009). Humic acids, fulvic acids and xenobiotic organic substances are not degraded (Gao et al., 2015).

20 Results and discussion Ammonia Nitrogen Phase 1 Phase 2

21 Results and discussion Unit A ( ) and unit B ( ) contribution for global removal efficiency of NH 4+ -N Global removal efficiencies Control: 56% HP: 74% Global removal efficiencies Control: 43% HP: 58%

22 Results and discussion Unit A NH 4 -N removal NO 3 increase IC removal

23 Unit B NH 4 -N removal Results and discussion NO 3 increase IC removal NITRIFICATION

24 Results and discussion Superficial O 2 diffusion Nitrification NH 4 NO 3 N-NH 4 Upflow flux Gradient [N-NH 4 ]

25 Results and discussion Organic Matter x Nitrogen Correlation between influent COD:TN and NH 4+ -N removal rate C Nitrification

26 Results and discussion Organic matter x Nitrogen Microorganism Competition regarding O2 use: Heterotrophic x Autotrophic For bioreactors operating in series, the nitrifiers microorganisms are more abundant in the last First units units (Zhu & Chen, 2001). Last units Oxidation of biodegradable organic matter Oxygen fully available for NH 4+ -N oxidation

27 Total Nitrogen Results and discussion TN removal: Unstable Mainly in units B (when NO 3- -N was present) Denitrification

28 Denitrification Results and discussion Hampered by lack of readily biodegradable organic matter as carbon source for microorganisms Nitrate accumulation Other routes characterized by partial nitrification and Anammox may have been partially responsible for nitrogen removal (Shalini and Joseph, 2012). Completely Autotrophic Nitrogen Removal Over Nitrite (CANON) Single reactor system for High Activity Ammonia Removal Over Nitrite (SHARON)

29 Conclusions Organic matter removal efficiency as COD was under 20% Leachate recalcitrance Pre-treatment for biodegradability enhancement NH 4+ -N average global removal efficiencies up to 74% Nitrification as the main removal route Influent COD:TN HRT + Low depth = large area demand No significant difference between HP and control

30 Conclusions Brazilian National Policy on Solid Waste Changes in solid waste management Open dumps Landfills = increased leachate collection Changes in leachate composition biodegradability Treatment technology

31 Thank you! Vitor Cano

32 SUMMER SCHOOL ON SUSTAINABLE WASTE MANAGEMENT IN DEVELOPING COUNTRIES AND EMERGING ECONOMIES Braunschweig, 31/10/2016

33 EFFECTS OF MORINGA OLEIFERA SEED EXTRACTS ON THE REMOVAL OF FAECAL BIOINDICATORS FROM LEACHATE IN VERTICAL FLOW CONSTRUCTED WETLANDS By NGANDJUI TCHANGOUE Yvan Anderson PhD student in Environmental and Organic Chemistry M.Sc. in Organic Chemistry option Biological Chemistry (Univ. Yaoundé I/Cameroon), M.Sc. in Sanitary and Environmental Engineering (International Institute for Water and Environment Engineering / Burkina Faso) Wastewater Research Unit / Laboratory of Natural Products and Microbiology, Univ. Yaoundé I yvanandersonn@gmail.com

34 TABLE OF CONTENT 1- INTRODUCTION 2- MATERIAL AND METHODS 3- RESULTS AND DISCUSSION 4- CONCLUSION ACKNOWLEDGEMENTS

35 INTRODUCTION (1/8) Sub-Saharan Africa countries are characterized by a rapid population growth which bring about severe challenges for accessing household food security and basic services amongst which sanitation (Wethe et al., 2003). With 90% of excreta managed by autonomous sanitation, it is a huge amount of faecal sludge that are produced daily and dumped in the environment due to lack of treatment plants. This practice constitutes a serious threat to public health and to the environment (Koné and Strauss, 2004). Faecal sludge (FS) or excreta are mixtures of human excrement, urine and wastewater produced from onsite sanitation technologies (e.g. pit latrines, public toilets, septic tanks) (Montangero and Strauss, 2002). Heinss (1998) subdivided faecal sludge into two types on the basis of their concentrations: type A and the type B.

36 INTRODUCTION (2/8) - Type A faecal sludge are sludge coming from public toilets or public surfaces (market, hostel, Institute, ) and that are stored for some few days or weeks only. They are relatively highly concentrated and are biochemically unstable. - Type B faecal sludge are sludge coming from on-site sanitation disposals (pit toilet, septic tanks,..). They have been stored for many years and are less concentrated and partially stable. In order to protect the environment and mainly water resources, many technologies are being used worldwide for wastewater treatment. They can be regrouped into two types according to the amount of wastewater they can threat, thus the number of equivalent inhabitants which is the main criteria for their dimensioning. We have: - Intensive processes, we note bacterial filters, biodiscs, activated sludge, biofiltration, rotating biological contactor (Liénard, 2004; Matamoros et al., 2016). - Extensive processes, we have constructed wetlands and waste stabilisation pond (Matamoros et al., 2016). Extensive treatment techniques are treatment processes in which the culture media are fixed on thin substratum or are free. (Kadlec and Wallace, 2009).

37 INTRODUCTION (3/8) According to WHO, 2012, 10% of the world s population is thought to consume wastewater irrigated foods. 20 million hectares in 50 countries are irrigated with raw or partially treated wastewater. The use of greywater is growing in both developed and less developed countries it is culturally more acceptable in some societies Wastewater can be an excellent resource. if it is managed safely.

38 INTRODUCTION (4/8) There have been many attempts to implement intensive wastewater treatment technologies (e.g. rotating biological contactors, activated sludge ), but they have proved not adapted to the African context for a number of reasons including the high cost of installation, the unavailability of a reliable energy supply, and insufficient local skills and human resources. Fig.1: Intensive wastewater treatment technologies previously used in Cameroon

39 INTRODUCTION (5/8) The development of research on this issue of treatment of wastewater and faecal sludge through simple and appropriate systems adapted to the socioeconomic context of African countries has been a concern for several years. Natural or passive systems also termed low-cost technologies (Strauss et al., 1997) such as planted drying beds for sludge and wastewater (i.e. vertical flow constructed wetlands (VFCWs)) provided a promising alternative. Among the techniques used, planted drying beds, which have been widely studied, have proved their efficiency in removing particulate and inorganic carbon pollution contained in wastewater and faecal sludge (Kengne et al., 2008 ; Fonkou et al., 2010 ; Soh et al., 2014).

40 INTRODUCTION (6/8) Their use for treatment of wastewaters from municipal, surface, storm, industrial, and agricultural sources has been well established (Cofie et al., 2006; Cooper, 2005; Kadlec and Wallace, 2009; Liénard et al., 2004; Stefanakis and Tsihrintzis, 2012; Vymazal,2007). In Cameroon, the use of this technique for the treatment of faecal sludge is recent. Echinochloa pyramidalis has been selected by Kengne et al. (2008) as auxiliary macrophyte because of its good treatment capacity (good liquid / solid separation), rapid reproduction, its easy management, its biomass recycling options and its reduction of pollutants. Despite the good performance of solid / liquid separation of planted sludge drying beds with Echinochloa pyramidalis, leachates released by their high physical, chemical and bacteriological characteristics showed the need for additional refining treatment before discharge in nature (Kengne et al., 2008, Kengne et al., 2011).

41 INTRODUCTION (7/8) The use of an additional planted sludge drying beds with Echinochloa pyramidalis to meet this demand has produced very good results on the physicochemical level, though the bacteriological aspect remains problematic (Soh et al., 2014). Recent studies have shown a strong disinfectant action of the coagulant from the seeds of Moringa oleifera with performances averaging 82-94%, % and % for faecal coliforms, Escherichia coli and faecal streptococci, respectively, when treating water intended for consumption (Kabore et al., 2013) and performances around 96.1% and 82.8% for total coliforms and Escherichia coli, respectively, during the treatment of domestic wastewater (Marcelo et al., 2013).

42 INTRODUCTION (8/8) The aim of the present study was to evaluate to what extent natural extract from Moringa oleifera seeds can be effective in polishing effluent from VFCW in 3 rd stage treatment and how the concentration of extract and the duration of decantation affect treatment performances.

43 Site investigation This study was conducted in-situ using pilot-scale Vertical Flow Constructed Wetlands (VFCW) installed on the campus of the University of Yaoundé I for the field part and in the Laboratory of Biotechnology and Environment at the University of Yaoundé I for the lab part. Experimental set up MATERIAL AND METHODS (1/4) Fig.2: Different steps of construction of the VFCW

44 MATERIAL AND METHODS (2/4) Collecting of faecal sludge and post leachate Fig.3: From faecal sludge to post leachate for analyses

45 Parameters considered MATERIAL AND METHODS (3/4) Some physico-chemical parameters like ph, temperature and redox potential (E) were assessed in situ. Conductivity, salinity and Total Dissolved Solid (TDS) were analysed in the laboratory according to the standard methodology (APHA, 2005). The faecal indicators of water pollution: Escherichia coli, faecal coliforms and faecal streptococci were also determined and quantified with the membrane filtration method and counted according to the standard protocol described by Rodier et al. (2009). Fig.4: Different steps of analysis of the parameters considered

46 MATERIAL AND METHODS (4/4) Extraction of coagulant from Moringa oleifera seeds The seeds were dried, peeled and crushed according to the technique described by Folkard and Sutherland (2002). Coagulation efficiency of M. oleifera seed extracts was assessed using the jar test in laboratory experiments (Muyibi and Alfugara, 2003; Ndabigengesere et al., 1995). According to literature (Amagloh et al., 2009; Sengupta et al., 2012; Kabore et al., 2013; Marcelo et al., 2013), different concentrations of coagulant (30 mg, 40mg and 50mg) were added to each triplet of glass and stirred. After stirring, each triplet was allowed to settle for three varying times (1h, 2h and 3h). Agitation of samples after the introduction of M. oleifera extract was in two phases: rapid stirring at 200 rpm for five minutes and slow stirring at 50 rpm for twenty minutes. Data analysis Data from the laboratory experiments were expressed as means and standard deviations (SD) and performed with statistical software GraphPad Prism 5.03 using ANOVA following Newman Keuls multiple comparison tests.

47 RESULTS AND DISCUSSIONS (1/12) Characteristics of different effluents from Vertical Flow Constructed Wetlands Cesspool Pit latrines Septic tanks Guidelines for Parameters Units discharge of effluent Mean SD* Mean SD* Mean SD* MINEP** WHO*** Eh (mv) NA NA TDS (mg/l) NA ph Temperature C NA NA Salinity ( ) NA Conductivity (µs/cm) NA NA Escherichia Coli Faecal streptococci Faecal coliform (Log CFU /100 ml) (Log CFU /100 ml) (Log CFU /100 ml) <3.3 < <3.0 NA <3.30 <3.0 This table shows differences on the characteristics of the three post-leachate of the faecal sludge used. Looking at the distribution of physicochemical parameters, it was observed that pit latrines exhibited higher TDS, salinity and conductivity than septic tanks and cesspool. Concerning bacteriological parameters, E. coli, faecal coliform and faecal streptococci are higher in effluent from faecal sludge of septic tanks than others. We also observed that effluent from faecal sludge of cesspool have smaller characteristics.

48 RESULTS AND DISCUSSIONS (2/12) Effects of concentrations of Moringa oleifera extracts at fixed settling time on bacteriological characteristics in cesspool In the post-leachate from cesspool, the effect was really appreciated for concentration of 50 mg during 180 min decantation time for faecal bio indicators. During these 3 hours, a total of 0.56 ulog, 0.62 ulog and 0.76 ulog, respectively, of E. coli, faecal streptococci and faecal coliforms were removed. Decantation time was significant (p= ) for E. coli (Fig. 2B), significantly higher (p= ) for faecal streptococci (Fig. 2C) and highly significant (p= ) for faecal coliforms (Fig. 2A).

49 RESULTS AND DISCUSSIONS (3/12) Effects of concentrations of Moringa oleifera extracts at fixed settling time on bacteriological characteristics in pit latrines The effect was also appreciated in the post-leachate from pit latrines during three times of decantation (60 min, 120 min and 180 min) for concentrations of 40 mg and 50 mg. During 3 hours, a total of 0.88 ulog and 0.93 ulog of faecal coliforms and E. coli were removed with a concentration of 40 mg, and 0.63 ulog of faecal streptococci were removed with a concentration of 50 mg. The Effect was significant (p= ) for faecal streptococci (Fig. 2E) and of higher significant (p= ) for E. coli (Fig. 2D), (p < ) for faecal coliforms (Fig. 2F).

50 RESULTS AND DISCUSSIONS (4/12) Effects of concentrations of Moringa oleifera extracts at fixed settling time on bacteriological characteristics in septic tanks With the post-leachate from septic tank, no significant reduction in E. coli (Fig.2G) and faecal coliform (Fig. 2I) was recorded but a slightly significant reduction (p= ) was noted with faecal streptococci (Fig. 2H). During the 3 hours, a total of 0.67 ulog of faecal coliforms were removed with a concentration of 40 mg, 0.73 ulog and 0.88 ulog, respectively, of faecal streptococci and E. coli were removed with a concentration of 50 mg.

51 RESULTS AND DISCUSSIONS (5/12) Effects of different settling times of decantation at fixed concentrations of Moringa oleifera extracts on bacteriological characteristics in cesspool In the post-leachate from cesspool, the effect of adding concentration of M. oleifera extract was significantly high (p= ) for faecal coliform (Fig. 3C) and highly significant (p= ) for E. coli (Fig. 3A), (p= ) for faecal streptococci (Fig. 3B).

52 RESULTS AND DISCUSSIONS (6/12) Effects of different settling times of decantation at fixed concentrations of Moringa oleifera extracts on bacteriological characteristics in pit latrines This effect was highly significant (P= ) for E. coli (Fig. 3E), (p= ) for faecal streptococci (Fig. 3D) and (p < ) for faecal coliform (Fig. 3F) in the post-leachate from pit latrines.

53 RESULTS AND DISCUSSIONS (7/12) Effects of different settling times of decantation at fixed concentrations of Moringa oleifera extracts on bacteriological characteristics in septic tanks The effect of adding the concentration of M. oleifera was significant (p= ) for E. coli (Fig. 3G), of higher significant (p= ) for faecal streptococci (Fig. 3I) and highly significant (p= ) for faecal coliform (Fig. 3H) in the post-leachate from septic tank.

54 RESULTS AND DISCUSSIONS (8/12) Best concentration and settling time of Moringa oleifera extract The ideal concentration of M. oleifera extract was highly dependent on the types of faecal sludge and their characteristics (Fig. 2&3). The optimum dosage for the treatment of faecal sludge from cesspool was 50 mg for E. coli, faecal coliforms and faecal streptococci for180 min. For pit latrines, the optimum dosage was 40 mg for E. coli and faecal coliforms for 180 min and 50 mg for faecal streptococci for 180 min. For septic tanks, 50 mg of extract for 180 min was selected as optimum dosage for E. coli and faecal streptococci, and 40 mg for 180 min too for faecal coliforms.

55 Effect of treatment with Moringa oleifera on ph Cesspool Pit latrines Septic tank Before After treatment Before After treatment Before After treatment treatment Conditions Mean treatment Conditions Mean treatment Conditions Mean ph 6.38±0.59 RESULTS AND DISCUSSIONS (9/12) 50mg - 2h 6.37± mg - 1h 6.48± mg - 1h 6.64± ± ± mg - 3h 6.24± mg - 2h 6.43± mg - 3h 6.24±0.69 It is noted that treatment with M. oleifera has little influence on the ph. There is a slight increase in ph with post-leachate from pit latrines, a slight decrease in ph with post-leachate from cesspool and a slight reduction and increase in ph with post-leachate from septic tank. No significant change of ph is observed.

56 RESULTS AND DISCUSSIONS (10/12) Correlation matrix with post-leachate from cesspool

57 RESULTS AND DISCUSSIONS (11/12) Correlation matrix with post-leachate from pit latrines

58 RESULTS AND DISCUSSIONS (12/12) Correlation matrix with post-leachate from septic tanks

59 CONCLUSION The results showed that Moringa oleifera seeds extract was able to reduce the percentage of Escherichia coli by %, faecal streptococci by % and faecal coliforms by % in different effluents of faecal sludge used. The best removal efficiency for Escherichia coli and faecal coliforms were obtained in the faecal post-leachates from pit latrines with values of 88.1% and 86.39% removal efficiencies respectively and for faecal streptococci it was in the post-leachates of septic tanks with values of 81.33% removal efficiency. Considering the fact that Moringa oleifera can be locally obtained due to its availability in many tropical countries, its use in faecal sludge leachate post treatment should be encouraged in order to reduce both the contamination risk and the high cost of the current wastewater treatment systems. However, additional improvements of leachate are suggested to meet the WHO and MINEP guideline thresholds for discharge or reuse in nonrestricted agriculture.

60 ACKNOWLEDGEMENTS THANK YOU FOR YOUR KIND ATTENTION