Effect of chemical dose on phosphorus removal and membrane fouling control in a UCT-MBR

Abstract

Phosphorus removal was enhanced effectively by dosing aluminum sulfate and effluent phosphorus concentration was lower than 0.5 mg/L.

Sludge activity was not inhibited but improved slightly with addition of aluminum sulfate.

EPS concentrations both in mixed liquid and on membrane surface were decreased, contributing to the effective mitigation of membrane fouling.

To enhance phosphorus removal and make the effluent meet the strict discharge level of total phosphorus (TP, 0.5 mg/L), flocculant dosing is frequently applied. In this study, the performance of aluminum sulfate dosing in a University of Cape Town Membrane Bioreactor (UCT-MBR) was investigated, in terms of the nutrients removal performance, sludge characteristics and membrane fouling. The results indicated that the addition of aluminum sulfate into the aerobic reactor continuously had significantly enhanced phosphorus removal. Moreover, COD, NH₄⁺-N and TN removal were not affected and effluent all met the first level A criteria of GB18918-2002. In addition, the addition of aluminum sulfate had improved the sludge activity slightly and reduced trans-membrane pressure (TMP) increase rate from 1.13 KPa/d to 0.57 KPa/d effectively. The membrane fouling was alleviated attributed to the increased average particle sizes and the decreased accumulation of the small sludge particles on membrane surface. Furthermore, the decline of extracellular polymeric substance (EPS) concentration in mixed sludge liquid decreased its accumulation on membrane surface, resulting in the mitigation of membrane fouling directly.

Graphical abstract

Keywords

University of Cape Town Bioreactor (UCT-MBR) / enhanced nutrients removal / aluminum sulfate / sludge activity / membrane fouling

References

[1] APHA (2012)Standard Methods for the examination of Water and Wastewater 22nd America Public Health Association, Washington DC, USA

[2] Arrojo B, Mosquera-Corra A, Garrido J M, Méndez R, Ficara E, Malpei F (2005). A membrane coupled to a sequencing batch reactor for water reuse and removal of coliform bacteria. Desalination, 179(1-3): 109–116

[3] Azami H, Sarrafzadeh M H, Mehrnia M R (2011). Fouling in membrane bioreactors with various concentrations of dead cells. Desalination, 278(1-3): 373–380

[4] Buisson H, Cote P, Praderie M, Paillard H (1998). The use of immersed membranes for upgrading wastewater treatment plants. Water Science and Technology, 37(9): 89–95

[5] Caravelli A H, Gregorio C D, Zaritzky N E (2012). Effect of operating conditions on the chemical phosphorus removal using ferric chloride by evaluating orthophosphate precipitation and sedimentation of formed precipitates in batch and continuous systems. Chemical Engineering Journal, 209: 469–477

[6] Cosenza A, Bella G D, Mannina G, Torregrossa M, Viviani G (2013). Biological nutrient removal and fouling phenomena in a University of Cape Town Membrane Bioreactor treating high nitrogen loads. Journal of Environmental Engineering, 139(6): 773–780

[7] Dalmau M, Rodriguez-Roda I, Ayesa E, Odriozola J, Sancho L, Comas J (2013). Development of a decision tree for the integrated operation of nutrient removal MBRs based on simulation studies and expert knowledge. Chemical Engineering Journal, 217: 174–184

[8] Díez-Montero R, De Florio L, González-Viar M, Herrero M, Tejero I (2016). Performance evaluation of a novel anaerobic-anoxic sludge blanket reactor for biological nutrient removal treating municipal wastewater. Bioresource Technology, 209: 195–204

[9] Drews A, Lee C H, Kraume M (2006). Membrane fouling—A review on the role of EPS. Desalination, 200(1-3): 186–188

[10] Dubois M, Gilles K A, Hamilton J K, Rebers P A, Smith F (1956). Colorimetric method for determination of sugars and related substances. Analytical Chemistry, 28(3): 350–356

[11] Fan F, Zhou H, Husain H (2007). Use of chemical coagulants to control fouling potential for wastewater membrane bioreactor processes. Water Environment Research A Research Publication of the Water Environment Federation, 79: 952–957

[12] Ferrero G, Monclús H, Buttiglieri G, Comas J, Rodriguez-Roda I (2011). Automatic control system for energy optimization in membrane bioreactors. Desalination, 268(1-3): 276–280

[13] Ge S, Peng Y, Wang S, Guo J, Ma B, Zhang L, Cao X (2010). Enhanced nutrient removal in a modified step feed process treating municipal wastewater with different inflow distribution ratios and nutrient ratios. Bioresource Technology, 101(23): 9012–9019

[14] Hu Y, Wang X C, Tian W R, Chen R (2014). Assessment of fouling potentials of extracellular polymeric sub-stances in a membrane bioreactor using modified fouling index (MFI). Journal of Water Sustainability, 4: 237–246

[15] Huang X, Wu J (2008). Improvement of membrane filterability of the mixed liquor in a membrane bioreactor by ozonation. Journal of Membrane Science, 318(1-2): 210–216

[16] Hussain S, Leeuwen J V, Chow C W K, Aryal R, Beecham S, Duan J, Drikas M (2014). Comparison of the coagulation performance of tetravalent titanium and zirconium salts with alum. Chemical Engineering Journal, 254: 635–646

[17] Leyva-Díaz J C, Muñío M M, González-López J, Poyatos J M (2016). Anaerobic/anoxic/oxic configuration in hybrid moving bed biofilm reactor-membrane bioreactor for nutrient removal from municipal wastewater. Ecological Engineering, 91: 449–458

[18] Li W, Cai Z Y, Duo Z J, Lu Y F, Gao K X, Abbas G, Zhang M, Zheng P (2017a). Heterotrophic ammonia and nitrate bio-removal over nitrite (Hanbon): Performance and microflora. Chemosphere, 182: 532–538

[19] Li X, Liu Y, Liu F, Liu A, Feng Q (2017b). Comparison of ferric chloride and aluminum sulfate on phosphorus removal and membrane fouling in MBR treating BAF effluent of municipal wastewater. Journal of Water Reuse and Desalination, 7(4): 442–448

[20] Liu T, Lian Y, Graham N, Yu W, Rooney D, Sun K (2016). Application of polyacrylamide flocculation with and without alum coagulation for mitigating ultrafiltration membrane fouling: Role of floc structure and bacterial activity. Chemical Engineering Journal, 307: 41–48

[21] Liu Y, Shi H, Li W, Hou Y, He M (2011). Inhibition of chemical dose in biological phosphorus and nitrogen removal in simultaneous chemical precipitation for phosphorus removal. Bioresource Technology, 102(5): 4008–4012

[22] Lowry O H, Rosebrough N J, Farr A L, Randall R J (1951). Protein measurement with the Folin phenol reagent. Journal of Biological Chemistry, 193(1): 265–275

[23] Mannina G, Capodici M, Cosenza A, Trapani D D (2016). Carbon and nutrient biological removal in a University of Cape Town Membrane Bioreactor: Analysis of a pilot plant operated under two different C/N ratios. Chemical Engineering Journal, 296: 289–299

[24] Monclús H, Sipma J, Ferrero G, Comas J, Rodriguezroda I (2010). Optimization of biological nutrient removal in a pilot plant UCT-MBR treating municipal wastewater during start-up. Desalination, 250(2): 592–597

[25] Morgan J W, Forster C F, Evison L (1990). A comparative study of the nature of biopolymers extracted from anaerobic and activated sludges. Water Research, 24(6): 743–750

[26] Rajesh Banu J, Uan D K, Yeom I T, Nair J (2009). Nutrient removal in an A²O-MBR reactor with sludge reduction. Bioresource Technology, 100(16): 3820–3824

[27] Ramesh A, Lee D J, Lai J Y (2007). Membrane biofouling by extracellular polymeric substances or soluble microbial products from membrane bioreactor sludge. Applied Microbiology and Biotechnology, 74(3): 699–707

[28] Satyawali Y, Balakrishnan M (2009). Effect of PAC addition on sludge properties in an MBR treating high strength wastewater. Water Research, 43(6): 1577–1588

[29] Song K G, Kim Y, Ahn K H (2008). Effect of coagulant addition on membrane fouling and nutrient removal in a submerged membrane bioreactor. Desalination, 221(1-3): 467–474

[30] Tang S, Wang Z, Wu Z, Zhou Q (2010). Role of dissolved organic matters (DOM) in membrane fouling of membrane bioreactors for municipal wastewater treatment. Journal of Hazardous Materials, 178(1-3): 377–384

[31] Trapani D D, Capodici M, Cosenza A, Bella G D, Mannina G (2011). Evaluation of biomass activity and wastewater characterization in a UCT-MBR pilot plant by means of respirometric techniques. Desalination, 269(1-3): 190–197

[32] Wang H, Dong W, Li T, Liu T (2014a). Enhanced synergistic denitrification and chemical precipitation in a modified BAF process by using Fe²⁺. Bioresource Technology, 151: 258–264

[33] Wang Z, Wu Z, Tang S (2009). Extracellular polymeric substances (EPS) properties and their effects on membrane fouling in a submerged membrane bioreactor. Water Research, 43(9): 2504–2512

[34] Wang Z Z, Jun L I, Gao J H, Jiang C, Ren J Z, Liu B (2014b). Effects of r(COD)/r(TN) on performance and membrane fouling in UCT-type Submerged Membrane Bioreactor. Journal of Beijing University of Technology, 40: 619–626 (in Chinese)

[35] Wu C, Zhou Y, Wang Y, Guo M (2016). Innovative combination of Fe²⁺-BAF and ozonation for enhancing phosphorus and organic micropollutants removal treating petrochemical secondary effluent. Journal of Hazardous Materials, 323(Pt B): 654–662

[36] Wu J, Chen F, Huang X, Geng W, Wen X (2006). Using inorganic coagulants to control membrane fouling in a submerged membrane bioreactor. Desalination, 197(1-3): 124–136

[37] Wu M, Jiang X, Lv Y, Zhou J, Yuan L, Jia Y, Wang Y (2015). Long-term effect of Cu (II) on the phosphorous removal performance in enhanced biological phosphorous removal systems. Chemical Engineering Journal, 281: 164–173

[38] Wvon M F S (1991). An improved and accurate method for determining the dehydrogenase activity of soils with iodonitrotetrazolium chloride. Biology and Fertility of Soils, 11(3): 216–220

[39] Xu G L, Fan Y B, Yan Y, Yang W J, Yuan D D, Wu G X (2010). Membrane fouling control in MBR achieved by dosing coagulants. Fresenius Environmental Bulletin, 19: 1591–1598

[40] Xu R, Zhou Z, Meng F (2018). The mechanical scouring of bio-carriers improves phosphorous removal and mediates functional microbiome in membrane bioreactors. Environmental Science. Water Research & Technology, 4(2): 241–252

[41] Yan M, Wang D, Ni J, Qu J, Chow C W K, Liu H (2008). Mechanism of natural organic matter removal by polyaluminum chloride: Effect of coagulant particle size and hydrolysis kinetics. Water Research, 42(13): 3361–3370

[42] Yao M, Zhang K, Li C (2010). Characterization of protein-polysaccharide ratios on membrane fouling. Desalination, 259(1-3): 11–16

[43] Zhang H, Wang X, Xiao J, Yang F, Zhang J (2009). Enhanced biological nutrient removal using MUCT-MBR system. Bioresource Technology, 100(3): 1048–1054

RIGHTS & PERMISSIONS

Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature