Electrokinetic technology applied to PPCPs removal from domestic effluent feasibility assessment

Transcription

1 5th International Conference on Sustainable Solid Waste Management, Athens, Electrokinetic technology applied to PPCPs removal from domestic effluent feasibility assessment Ana Rita Ferreira, Paula Guedes, Eduardo P. Mateus, Nazare Couto, Alexandra B. Ribeiro

2 What are Pharmaceuticals and Personal Care Products (PPCPs)? Any product used by individuals for personal health or cosmetic reasons or used by agribusiness to enhance growth or health of livestock (U.S.EPA) Annual production exceeds 10 6 tworldwide Effluent with PPCPs Receiving water Soil PPCPs WWTP 2

3 Why are PPCPs a problem? E.g.: biological effects (including estrogenicity, mutagenicity and genotoxicity) antibiotic resistant organisms 3

4 Goals Develop a cost effective electro technology to decrease PPCPs concentrations from the effluent in wastewater treatment plant (WWTP) In the present work: the behaviour of PPCPs during electrokinetic process was assessed testing different current intensity (25, 50, 75, 100 ma) EK reactor with continuous entry of effluent testing: the anode electrode with different shape: bar vs. mesh different current intensity 4

5 PPCPs in study Compound Category Formula MW (g mol 1 ) Log K ow pka Sol. In water (mg L 1 ) Bisphenol A (BPA) Plasticizer C 15 H 16 O a ethinylestradiol (EE2) estrogen C 20 H 24 O Oxybenzone (MBPh) UV filter C 14 H 12 O Sulfamethoxazole (SFM) antibiotic C 10 H 11 N 3 O 3 S Diclofenac (DCF) antiinflammatory C 14H 11 Cl 2 NO Carbamazepine (CBP) Anticonvulsive C 15 H 12 N 2 O

6 Methodology Preliminary tests Stationary cell with agitation Electrodes: Platinized titanium bars Deionized water PPCPs in study: BPA, MBPh, DCF I(mA) Time (h) PPCPs concentration (ppm) (+) ( ) 6

7 Methodology EK set up Vertical EK reactor with continuous flow (2 ml min 1 ) of effluent Electrodes: Platinized titanium bar vs. mesh PPCPs in study: BPA, EE2, MBPh, SFM, DCF, CBP 10 cm Anode EFFLUENT + 3 ppm PPCPS Catahode Treated EFFLUENT internal diameter = 8 cm 7

8 Methodology EK set up Electrodes Cathode: platinized titanium bar Anode: platinized titanium bar vs. mesh Bar (left) and mesh (right) electrodes 8

9 Methodology EK conditions I (ma) Time* (h) PPCPs concentration (ppm) * Residence time of the effluent in EK reactor 9

10 Methodology effluent collection The effluent was collected after the secondary settling tank in awwtp; The WWTP has the capacity to treat in the project horizon m 3 day 1 of urban wastewater, corresponding to about equivalent inhabitants; Before the experiments the effluent was filtered. 10

11 EK preliminary results (+) ( ) % Degradation I (ma) BPA DCF MBPh 11

12 EK preliminary results Kinetics for three PPCPs in study under 100 ma of current Time (min) ,1 Ln (C/C0) 0,2 0,3 0,4 0,5 0,6 y = 0,0024x R² = 0,9353 y = 0,0027x R² = 0,9471 y = 0,0028x R² = 0,9477 BPA DCF MBPh Linear (BPA) Linear (DCF) Linear (MBPh) Pseudo first order kinetics ( (C0/C) = ) of removal (k x 10 2 min 1 ) I (ma) BPA DCF MBPh k k k Note: Extra information can be found in Poster n.36: P. Guedes, A. R. Ferreira, N. Couto, E. Mateus, M. G. Silva, A. B. Ribeiro (2017) Degradation kinetics of emerging organic contaminants subjected to electro and photo degradation 12

13 General results EK reactor Anode (platinized titanium) Current (ma) Voltage (V) Conductivity (ms cm 1 ) ph Initial Final Initial Final Initial Final bar Mesh bar Mesh

14 Results 25 ma experiment bar 25 ma mesh 25 ma Removal (%) Removal (%) SFM CBP BPA EE2 DCF MBPh 0 SFM CBP BPA EE2 DCF MBPh 14

15 Results 100 ma experiment bar 100 ma mesh 100 ma Removal (%) Removal (%) SFM CBP BPA EE2 DCF MBPh 0 SFM CBP BPA EE2 DCF MBPh CBP (pka = 13.9) was the least removed contaminant (16 18%) comparing to the other studied PPCPs (4.14<pKa<10.3); MBPh (pka = 7.56) the most removed contaminant (89 90%); No differences were found comparing bar with mesh as anode electrodes in the tested conditions. 15

16 Conclusions Preliminary results show that the electrokinetic process (EK) is a viable option for PPCPs removal from effluent > Removals between 16 and 89%; PPCPs showed different removal rates mainly attributed to their characteristics; The shape of electrode did not show to have influence in PPCP removals; Reduction in electrical consumption can be achieved with a different electrode shape > Use of mesh can help in lowering energy consumption because of the higher surface area; Further studies are needed in order to improve the PPCPs removal with EK. 16

17 Acknowledgments AdP: Dr. Cristina Santos for providing the effluent samples, Dr. Olga Paredes and the Laboratory of Control and Processes for their assistance. Financial support was provided by 4KET4Reuse (SOE1/P1/E0253), co financed by the European Regional Development Fund (FEDER) and by CENSE Center for Environmental and Sustainability Research which is financed by national funds from FCT/MEC (UID/AMB/04085/2013). N. Couto and P. Guedes acknowledge Fundação para a Ciência e a Tecnologia for their Post Doc fellowships, respectively, SFRH/BPD/81122/2011 and SFRH/BPD/114660/

18 Thank you/ Obrigada/ ευχαριστώ Ana Rita Ferreira, Paula Guedes, Eduardo P. Mateus, Nazare Couto, Alexandra B. Ribeiro* CENSE, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Campus de Caparica, Caparica, Portugal *Presenting author abr@fct.unl.pt 18