type) for winery wastewater treatment at low temperatures N. - - PowerPoint PPT Presentation
AnMBR technologies (CSTR and UASB type) for winery wastewater treatment at low temperatures N. Basset*, M.E. de Arana-Sarabia**, C. Vidal*, A. Coll*, I. Fernndez *, J. Dosta* and J. Mata- lvarez * *Department of Chemical Engineering and
Fernández*, J. Dosta* and J. Mata-Álvarez* *Department of Chemical Engineering and Analytical Chemistry, University of Barcelona **Department of Engineering and Architecture, University
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France 16% Italy 16% Spain 12% USA 8% China 6% Australia 5% Chile 5% Rest of the world 32%
France Italy Spain USA China Australia Chile Rest of the world
Wine production (·103hL) (source: International Organization of Vine and Wine ) Country 2010 2011 2012 France 44322 50757 41422 Italy 48525 42772 40060 Spain 35353 33397 30392 USA 20887 19187 20517 China 13000 13200 14880 Australia 11420 11180 12660 Chile 8844 10464 12554 Rest of the world 81649 86043 79515 Total 264000 267000 252000
World wine production
Up to 4 L wastewater L-1 wine produced
Intensive and compact technologies: AnMBR Energy recovery
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Winery wastewater characteristics and CSTR-MBR set up
Anaerobic CSTR of 4L coupled to an external membrane unit
PVDF flat-sheet 0.25 µm pore size 100 cm2 of area TMP = 0.2 bar Biogas counter: Ritter MGC-1 Feed by pressure equilibrium Peristaltic pump 30 L/h
Winery wastewater main characteristics pH 4.67 ± 0.42 tCOD (mg/L) 6752 ± 663 sCOD (mg/L) 4040 ± 692 NH4
+-N (mg/L)
4.99 ± 1.66 PO4
3—P (mg/L)
4.55 ± 1.63 COD/N 1352 COD/P 1484 Orelis, Rayflow Module
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Objectives Test the AnMBR at low temperatures of 25ᵒC and 15ᵒC
Operational conditions HRT = 4 days SRT = 500 days Influent COD = 1-1.5g/L MLSS = 2.7 g/L Alkalinity = 900 mg/L TMP = 0.2 bar Vc = 0.64 m/s
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25ᵒC
100 200 300 400 500 600 20 40 60 80 100 VFA (mg L-1) COD removal (%)
COD removal VFA
0,00 0,05 0,10 0,15 0,20 0,25 0,30 0,35 5 10 15 20 25 30 45 55 65 75 85 95 105 sOLR (kgCOD kg-1MLSS d-1) Flux (LMH) Time (d)
Flux Cleaning sOLR
15ᵒC
0,00 0,05 0,10 0,15 0,20 0,25 0,30 0,35 0,40 5 10 15 20 25 30 5 10 15 20 25 30 35 40 45 sOLR (kgCOD kg-1MLSS d-1) Flux (LMH) Time (d)
Flux Cleaning sOLR
50 100 150 200 250 300 350 400 450 25 50 75 100 VFA (mg L-1) COD removal (%) COD removal VFA
High VFA High sOLR Acclimation High VFA High sOLR
After a cleaning, flux and sOLR increased
80% COD removal 70% COD removal
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Results summary and comparison
Operational parameters Temperature 15ᵒC 25ᵒC 35ᵒC COD influent (g L-1) 1.10±0.30 1.41±0.39 2.92±1.05 COD effluent (g L-1) 0.39±0.15 0.28±0.14 0.14±0.23 %COD removal 71±9 80±9 96±4 OLR (kgCOD m-3
digester d-1 )
0.29±0.21 0.35±0.19 1.32±0.51 sOLR (kgCOD kg-1MLSS d-1 ) 0.11±0.07 0.13±0.09 0.22±0.09 Membrane performance Flux (LMH) 13.8±6.8 12.2±4.4 16.0±3.9 Flux decline (LMH d-1) 3.36±1.03 2.14±1.62 0.10±0.04
Effluent COD higher due to VFA Higher degree of fouling at similar fluxes
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FISH
15ᵒC
Methanosaeta spp. Methanosarcina spp. High VFA in the digester
25ᵒC 25ᵒC
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Objectives
The Upflow Anaerobic Sludge Blanket (UASB) is one of the most used configuration Interesting to apply at low temperature anaerobic digestion, higher biomass concentration Improve the subsequent filtration step due to low SS in the clarified effluent
Winery wastewater treatment at room temperature (20 ᵒC)
Volume = 1.5 L HRT = 16 h H/D = 3 MLSS = 30-40 g/L Upflow velocity = 1 m/h
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Higher OLR up to 5.5 kgCOD m-3 d-1 Lower sOLR <0.06 kgCOD kgMLSS-1 d-1 MLSS around 40 g L-1 Effluent COD > 125 mg L-1 (effluent SS↑) Effluent sCOD < 125 mg L-1
Upflow anaerobic sludge blanket (UASB)
COD removal of 80% SMP of 0.20 Nm3CH4 kg-1CODadded 97% of methane in biogas
Important wash out of solids in the effluent Good sCOD removal, not very good total COD removal Introduction of the membrane: UASB-MBR
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UASB-MBR
COD removal > 90% SMP of 0.17 Nm3CH4 kg-1CODadded 95% of methane in biogas Effluent free of SS Minimise losses of SS in the effluent Accomplish discharge limits Avoid biomass wash-out
0% 20% 40% 60% 80% 100% 0,0 0,5 1,0 1,5 2,0 5 10 15 20 25 30 35 40 45 COD removal COD (g L-1 ) Time (d) Influent COD Permeate COD COD removal (%) 0,0 0,5 1,0 1,5 2,0 2,5 3,0 5 10 15 20 25 30 5 10 15 20 25 30 35 40 45 OLR (kgCOD m-3 d-1) Flux (LMH) Time (d) Flux OLR
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Microbial population (FISH)
Methanosaeta was the main methanogen
Methanosaeta spp. Archaea Bacteria
Although VFA were present in the effluent, Methanosarcina spp. was not detected Granules protect methanogens so VFA concentration may be lower in the inner layers
CSTR-MBR and UASB-MBR were successfully treating winery wastewater at low
UASB-MBR at 22 °C) Both reactors showed acclimation to the typical seasonal variability of the winery wastewater (low load and low temperature in winter and high load and relatively high temperature in summer). Due to the VFA accumulation and the dissolved methane, a post-treatment of the effluent would be necessary to meet the legislation. On the other hand, after that post-treatment, the solids-free effluent would be appropriate for a potential reuse. Higher degree of fouling compared with mesophilic AnMBR was observed. This fouling level was similar in both CSTR-MBR and UASB-MBR. The microbial population in the CSTR-MBR shifted from Methanosaeta spp. to Methanosarcina spp. because the high VFA concentration favoured the development
concentration.