DOW ClO2 Impact on RO Membrane ECO vs XFR Case Study Echo Zhao,Cheng Yang,Hugh Zhu,Yanhong He,Robert Chu
ClO2 Impact on RO Membrane ECO vs XFR Case Study Echo Zhao, Cheng Yang, Hugh Zhu, Yanhong He, Robert Chu
Outline .ClO2 impact on RO One Project Highlight for WRU in China ClO2 Impacts on RO summary Membrane Soaking Test at ClO2/Hypochlorite Solution .ECO vs XFR case study ·Pilot Overview ECO's Advantage for Energy Saving and Permeate Quality Dow
Outline •ClO2 impact on RO • One Project Highlight for WRU in China • ClO2 Impacts on RO summary • Membrane Soaking Test at ClO2/Hypochlorite Solution •ECO vs XFR case study • Pilot Overview • ECO’s Advantage for Energy Saving and Permeate Quality
1000T/H Petrochemical Wastewater Reclamation Project By Pass:70 T/H 1st stage UF 245T/H Pure Water 2nd stage 3rd stage Item Parameters Item Parameters RO System Total Capacity 980T/H RO Element BW30FR-400/34i RO Racks 4 Racks PV Staging per Rack 36+18+12(3 stage) RO Capacity per Rack 245T/H Pressure Vessel(PV) 7 RO elements/PV Blended Water per Rack 70T/H 1st stage 2 bar,Back Pressure RO System Recovery 70% 3rd stage 3 bar,Booster Pressure Dow
1000T/H Petrochemical Wastewater Reclamation Project 1 st stage 2 nd stage 3 rd stage Pure Water UF By Pass: 70 T/H Item Parameters Item Parameters RO System Total Capacity 980 T/H RO Element BW30FR-400/34i RO Racks 4 Racks PV Staging per Rack 36 +18 +12 (3 stage) RO Capacity per Rack 245 T/H Pressure Vessel(PV) 7 RO elements/PV Blended Water per Rack 70 T/H 1 st stage 2 bar, Back Pressure RO System Recovery 70% 3 rd stage 3 bar, Booster Pressure 245 T/H
RO system 3rd stage Could ClO2 be utilized as disinfectant in polyamide RO system? 1st 2nd stage
RO system 1 st stage 2 nd stage 3 rd stage
ClO2 impact on RO:safe or unsafe? Tolerance/ pH Rejecti on/% Author ppm.h 3 97.4 1200 5.8 93 1200 J.Glater,et al. 8.6 48 1200 7 96 4800 120 7 90 7800 100 360 7800 4734 336 7 70 13200 W.R.Adams et al 100 100 12 100.8 100 3.5 99 12000 ￥ 0 1200 12000 8.5 92 7200 1200 80 3360028000 8.1 99* 144 E.You et al. 7* 99* 12 E.L.Mainz et al. 13200 98.47 100 里 46 7 99.39 100 E.Alayemiek et al. 1200 40 9 97.97 100 7 99* 360 ClO2 tolerance/ppm.hr ●228 A.R.Pitochelli et 1 99* 33600 20 2 4 6 10 e 99* 100.8 G.D.Simpson et al. pH 99 336 T.J.Tseng 7.5 99* 28000 P.K.Eriksson 8.2 50 468 9.3 31 228 P.K.Eriksson 6.2 99 4734 94 50000 R.Sandin Dow
ClO2 impact on RO: safe or unsafe? 1200 1200 1200 4800 7800 13200 12000 7200 144 100 1 2 100 100 360 33600 100.8 336 28000 468 228 4734 50000 20 40 60 80 100 120 2 4 6 8 10 Rejection/% pH ClO2 tolerance/ppm.hr pH Rejecti on/% Tolerance/ ppm.h Author 3 97.4 1200 5.8 93 1200 J. Glater, et al. 8.6 48 1200 7 96 4800 W.R. Adams et al. 7 90 7800 7 70 13200 3.5 99 12000 8.5 92 7200 8.1 99** 144 E. You et al. 7* 99** 12 E. L. Mainz et al. 4 98.47 100 7 99.39 100 E. Alayemiek et al. 9 97.97 100 7 99** 360 A.R. Pitochelli et 7 99** 33600 al. 8 99** 100.8 G.D. Simpson et al. 7* 99 336 T.J. Tseng 7.5 99** 28000 P.K. Eriksson 8.2 50 468 9.3 31 228 P.K. Eriksson 6.2 99 4734 8 94 50000 R. Sandín
ClO2 production at lab-scale Air pump DI water Reaction Saturated DI water Water mixture sodium chlorite 5NaClo,+4HCl 4C10,1 +5NaCl+2H2O Cl2+2Nacl02→2cl02↑+2Nacl Dow
ClO2 production at lab-scale
Oxidant calculation during soaking test A ◆-C102 -NaClo 0.00 200.00 400.00 600.00 800.00 ◆ Time/h 8000 6000 4000 c102 ☏-NaClO 2000 0 0.00 200.00 400.00 600.00 800.00 Time/h Dow
Oxidant calculation during soaking test 0 2000 4000 6000 8000 10000 12000 14000 0.00 200.00 400.00 600.00 800.00 Oxidant accumulation/ppm.h Time/h ClO2 NaClO 0 5 10 15 20 0.00 200.00 400.00 600.00 800.00 Oxidant concentration/ppm Time/h ClO2 NaClO
Membrane performance test C02: 12,000ppm.h 120.00% 100.00% ◆BW30 80.00% 鲁BW30-C102 uolppafau iles 盒BW30-NaClO 60.00% NaClO: 40.00% 3000 ppm.h 20.00% 0.00% 0.00 200.00 400.00 600.00 800.00 Time/h Dow
Membrane performance test 0.00% 20.00% 40.00% 60.00% 80.00% 100.00% 120.00% 0.00 200.00 400.00 600.00 800.00 Salt rejection Time/h BW30 BW30-ClO2 BW30-NaClO NaClO: 3000 ppm.h ClO2: 12, 000 ppm.h
BW30 SEM image at 12,000 ppm.h 120.00% 100.00% 800% 60.00% 40.00% 2n0% 0.00 0.00 500.00 000.00 500.0 BW30-NaCIo BW30-CIO2 D 5wP3网，Wme
0.00% 20.00% 40.00% 60.00% 80.00% 100.00% 120.00% 0.00 500.00 1000.00 1500.00 Salt rejection Time/h A B C D BW30 BW30 BW30-NaClO BW30-ClO2 DOW RESTRICTED SEM image at 12, 000 ppm.h
Conclusions 。 BW30 performance deteriorated in NaClO after 3000ppm.h;whereas BW30 can maintain the enhanced salt rejection performance in pure ClO2 solution for 12,000ppm.h; The microscopic structural characterization further elucidates the slightly impaired membrane surface by chlorine dioxide,showing chlorine dioxide COULD also oxidize polyamide RO,compared with the seriously corroded surface morphology by hypochlorite. Chlorine dioxide holds promise for treating the severe biofouling threatened RO system,at the cost of lifetime reduction in a certain extent.It is still recommended to monitor the system performance closely and strictly control the concentration and purity of dosed chlorine dioxide. 12000ppm.hours/0.4ppm =30,000 hours 3.75 years Dow
Conclusions • BW30 performance deteriorated in NaClO after 3000ppm.h; whereas BW30 can maintain the enhanced salt rejection performance in pure ClO2 solution for 12, 000ppm.h; • The microscopic structural characterization further elucidates the slightly impaired membrane surface by chlorine dioxide, showing chlorine dioxide COULD also oxidize polyamide RO, compared with the seriously corroded surface morphology by hypochlorite. • Chlorine dioxide holds promise for treating the severe biofouling threatened RO system, at the cost of lifetime reduction in a certain extent. It is still recommended to monitor the system performance closely and strictly control the concentration and purity of dosed chlorine dioxide. 12000ppm.hours/0.4ppm = 30, 000 hours = 3.75 years