Start-Up of a decentralized pilot plant for the anaerobic treatment - PowerPoint PPT Presentation

Start-Up of a decentralized pilot plant for the anaerobic treatment of domestic wastewater Laura Fröba , Marisela Vega, Frauke Groß, Antonio Delgado 16.09.16

Objective of the study - autarc wastewater treatment of small settlements and megacities industrial scale (capacity: 200 m³/ d; PE 2000) - - saving drinking quality water by using service water (saving potential about 60%) self-defined limit values domestic wastewater (AbwV 2016, BayBadeGewV 2008) anaerobic COD: 200 mg/l COD: 75 mg/l NH4-N: 40 mg/l NH4-N: 10 mg/l service domestic TN: 50 mg/l TN: 13 mg/l wastewater water TP: 5 mg/l TP: 1 mg/l E.coli: 10^6 cfu/100ml E.coli 900 cfu/ 100 ml decentral easy to use pilot scale industrial scale lab scale 2 m³/ d 2 00 m³/ d  0,014 m³/ d 20 PE 2000 PE 2

Pilot plant for treating domestic wastewater • three stage biological process • C-reduction: anaerobic digestion reactor 1 (R1) and 2 (R2) • N-reduction: anaerobic Ammonium Oxidation (Anammox) reactor 3 (R3) • pre-heating step due to mesophilic conditions (30 ° C-40 ° C) • reactors: R1 + R3 : anaerobic sequencing batch reactor (1300 liters each) R2: fixed bed reactor domestic R2 wastewater R1 R3 Buffer service tank buffer tank reactor 1 reactor 2 reactor 3 sand filter activated carbon water post-treatment pre-heating anaerobic digestion Anammox 5

Pilot plant for treating domestic wastewater • installation in office container (28 m², H: 2.50 m)  flexible, modular and space efficient (decentral) reactor 2 post treatment reactor 3 reactor 1 buffer caustic electrical cabinet • reactors were innoculated each with 60 liters of seeding sludge • R1+R2: sludge coming from a two-stage anaerobic digestion plant (Obermichelsbach, GE) • R3: sludge coming from a Deammonification (DEMON)-System (Fulda, Gläserzell , GE) 5

Start-Up of the pilot plant • start-up procedure (MWW: municipal wastewater, SWW: synthetic wastewater) reactor 1 reactor 2 reactor 3 adaptation adaptation phase adaptation phase phase 100% MWW + organic acids 100% SWW 100% MWW (acetic acid: propionic acid: (1000 liters of tab water added butyric acid in 2:1:1) with ammonia sulfate (40mg/l) and sodium nitrite (50mg/l)) stepwise interconnection of R1 and R2 to 33%, 50%, 75% and 100%  100%: no addition of organic acids to R2 stepwise interconnection of anaerobic digestion (outlet of R2) and R3 to 20%, 50%, 80% and 100%  100%: - no addition of ammonia sulfate to R3 - adjsutment of nitrite-nitrogen (NO2-N) to ammonia-nitrogen (NH4-N) ratio • testing of the three-stage pilot plant for 200 days of operation after start-up  feeding of 100% MWW  additive: sodium nitrite (R3) 5

Start-Up of the two-stage anaerobic digestion (R1 + R2) 100 1050 inlet COD [mg/l] (I) (II) (III) COD [mg/l] 975 COD removal efficiency [%] chemical oxygen demand 90 outlet COD [mg/l] 900 COD removal efficiency [%] 80 825 750 70 (COD) [mg/l] 675 60 600 525 50 450 40 375 30 300 225 20 150 10 75 0 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 batch-no. adaptation phase (R2)  COD removal efficiency increased from 31% to 53% (I)  Start-up of two-stage anaerobic digestion was (II) Interconnection of R1 to R2 (33%, 50%, 75%,100%) successful  COD removal efficiency increased to 71%  Self-defined service water limit value of 75 mg/ l (III) Testing of the two-stage anaerobic digestion could almost be reached  average COD removal efficiency 62% 6

Start-Up of the Anammox-stage (R3) 120 120 NH4-N [mg/L] (I) (V) (VI) NH4-N removal efficiency 110 start NO2-N [mg/l] nitrogen concentration 100 100 NH4-N Removal efficiency [%] 90 (II) (III) (IV) 80 80 70 [mg/L] [%] 60 60 50 40 40 30 20 20 10 0 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 batch-No. (I): 100% SWW, (II): 20% MWW (III): 50% MWW, (IV): 80% MWW, ( Ⅴ ): 100% MWW  start-up of the Anammox-stage was successful adaptation phase (R3)  NH4-N removal efficiency inbetween 80% to 90% (I)  self-defined service water limit value of 10 mg/ l could be (I)-(V) interconnection of anaerobic digestion to R3 (20%, 50%, 80%, 100%) reached  NH4-N removal efficiency decreased from 72% to 48%  Optimum substrate to feed ratio of the Anammox-stage in pilot (VI) adjustment of substrate to feed ratio (NO2-N/ NH4-N)  NH4-N removal efficiency rised to 92% scale: 1.14 mg/ l 7

Degradation performance after 200 days of operation NH4-N concentration [mg/ l] 80 100% removal efficiency [%] Self-defined service water 70 80% 60 limit values: 50 50 46 60% COD: 75 mg/ l 40 96% NH4-N: 10 mg/ l 40% 30 20 20% COD-concentration [mg/ l] 300 100% 10 removal efficiency [%] 1 0 0% 250 80% 212 21% av. inlet NH4-N of MWW [mg/l] 200 60% av. outlet NH4-N after reactor 2 {mg/ l] 150 av. outlet NH4-N after reactor 3 [mg/ l] 85 40% av. NH4-N removal efficiency in reactor 3 [%] 100 60% 39 20% 50  further optimization of 2-stage 0 0% anaerobic digestion needed av. inlet COD of MWW [mg/l]  with Anammox-stage limit value is av. outlet COD after reactor 2 {mg/ l] av. outlet COD after reactor 3 [mg/ l] guaranteed av. COD removal efficiency after reactor 2 [%] av. COD removal efficiency in reactor 3 [%] 8

Conclusion • start-up of the two-stage anaerobic digestion (R1 + R2)  for a temperature range of 34 ° C to 38 ° C • • without automated pH-control • final average COD removal efficiency: 62% • start-up of the Anammox-stage (R3)  for a temperature range of 28 ° C to 35 ° C • • optimum NO2-N to NH4-N ratio: 1.14 • final average NH4-N removal efficiency: 92% • after testing the pilot plant for 200 days of operation • total COD removal efficiency is 81%   self-defined service water limit value of 75 mg/l could always be reached with R3 connected in downstream • total NH4-N removal efficiency is 96%   self-defined service water limit value of 10 mg/l could always reached only by R3  two-stage anaerobic digestion is limiting process-step, thus further optimization is needed to increase the plant ´ s capacity 9

Acknowledgements: • Hans Sauer Stiftung • Klärwerk Erlangen • Siemens AG • ZWT Wasser- und Abwassertechnik GmbH • Maschienenbau Biermann GmbH • Webfactory GmbH Thank you for your attention! sand filter activated carbon buffer tank reactor 1 reactor 2 reactor 3 pre-heating anaerobic digestion post-treatment Anammox 10

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Challenges of the project Varying operating parameters different wastewater (pH, T) concetrations composition (seasonal) (place of installation) guarantee Process stability odourless automated Challenges of easy to use domestic space saving robust decentral purpose installation noise emission low < 35 dB maintenace energy- and cost efficency low investment low operation costs costs

Concept of the pilot plant V_R3_4 pH QIRC base 330 V_R3_1 conductivity VB_1 V_R3_3 Φ 1“ PVC VB_2 QIRC BV_R3 Biogas 340 TRC influent TRC 320 120 pH NH4 QIRC QIRC V_R2_ V_R3_2 V_R1_ V_R2_1 M 2 M 6 130 140 3 2 V_P_ 1 LSH M 10 LSH LSH R1 R2 R3 112 212 312 Φ 1“ PVC M 1 M 5 LSH Puffer- buffer- V_R2_2 001 tank tank 1“ PVC M 4 Nitrogen Organikabbau Organic Organic removal digestion (2. Stufe) digestion (3. step) (2. step) (1. step) V_R1_5 M 7 LSL 002 Φ 1“ PVC V_R1_1 LSL LSL 111 311 pH V_R3_5 TR LSL QIRC 211 220 230 Sandfilte Sandfilte Sandfilte Activated r r r carbon 3 1 2 V_N_7 V_N_6 V_N_5 buffer- V_A_1 tank V_N_2 Effluent Φ 1“ PVC

Conecpt of process control basic automation (PCS7) Fuzzy-Neuro State experts ystem detection ES/OS-Single Station CPU 417-4H (Web-Anbindung) [SIMATIC PCS7] PG- Gerät plant bus Ablaufplan Profibus DP I/O-cuppler DC-USV [ET 200 M] [IM 153 -2] Basic automation and process DP/ PA - monitoring Link analytics R 1 R 2 R 3 R 1 R 2 R 3 Online: Temperature X X X temperature sensors Profibus PA pH X X X conductivity X Offline: COD X X X NH4-N X X FU FU analytic sensors TN X (Hach-Lange)

Methods for guaranteeing process stability Process Fuzzy Logic (FL) Proportional Integral stability Differential (PID) controller (expert knowledge)  For pH-control  for state detection Freezing Cool Warm Hot 1 0 10 30 50 70 90 110 Temp. (F ° ) Mathematic models Artificial Neuronal Nets (ANN) (differential equations)  Protection against overload in anaerobic  Estimation of NH4 degradation based on Δ pH/ Δ t digestion (Anaerobic Digestion Model No. 1) Input Net: pH, HRT / Otuput Net: Acetic, Butyric & Propionic Acid 4000 pH = 8 3500 pH = 6 3000 2500 Concentration [mg/l] Acetic Net Butyric Net Propionic Net 2000 Acetic Exp Butyric Exp 1500 Propionic Exp 1000 500 0 0 50 100 150 200 250 300 350 400 450 Time [h]