References

  1. A.A.L. Zinatizadeh, A.R. Mohamed, M.D. Mashitah, A.Z. Abdullah, M.H. Isa, Optimization of pre-treated palm oil mill effluent digestion in an up-flow anaerobic sludge fixed film bioreactor: a comparative study, Biochem. Eng. J., 35 (2007) 226–237.
  2. M. Ashokkumar, The characterization of acoustic cavitation bubbles - an overview, Ultrason. Sonochem., 18 (2011) 864–872.
  3. X. Feng, H. Lei, J. Deng, Q. Yu, H. Li, Physical and chemical characteristics of waste activated sludge treated ultrasonically, Chem. Eng. Process: Process Intensif., 48 (2009) 187–194.
  4. S.-K. Cho, Y.-H. Hwang, D.-H. Kim, I.-S. Jeong, H.-S. Shin, S.-E. Oh, Low strength ultrasonication positively affects the methanogenic granules toward higher AD performance. Part I: physico-chemical characteristics, Bioresour. Technol., 136 (2013) 66–72.
  5. F. Hogan, S. Mormede, P. Clark, M. Crane, Ultrasonic sludge treatment for enhanced anaerobic digestion, Water Sci. Technol., 50 (2004) 25–32.
  6. J. Jin, X. Zheng, X. Chu, Y. Chi, J. Yan, K. Cen, Oil recovery from oil sludge through combined ultrasound and thermochemical cleaning treatment, Ind. Eng. Chem. Res., 51 (2012) 9213–9217.
  7. S. Pilli, P. Bhunia, S. Yan, R.J. LeBlanc, R.D. Tyagi, R.Y. Surampalli, Ultrasonic pretreatment of sludge: a review, Ultrason. Sonochem., 18 (2011) 1–18.
  8. K.S. Suslick, N.C. Eddingsaas, D.J. Flannigan, S.D. Hopkins, H. Xu, Extreme conditions during multibubble cavitation: sonoluminescence as a spectroscopic probe, Ultrason. Sonochem., 18 (2011) 842–846.
  9. U. Neis, Ultrasound in water, wastewater and sludge treatment, Water, 21 (2000) 36–39.
  10. Y.G. Adewuyi, Sonochemistry: environmental science and engineering applications, Ind. Eng. Chem. Res., 40 (2001) 4681–4715.
  11. N.H. Ince, G. Tezcanli, R.K. Belen, İ.G. Apikyan, Ultrasound as a catalyzer of aqueous reaction systems: the state of the art and environmental applications, Appl. Catal. B, 29 (2001) 167–176.
  12. S. Manickam, N. Zainal Abidin, S. Parthasarathy, I. Alzorqi, E.H. Ng, T.J. Tiong, R.L. Gomes, A. Ali, Role of H2O2 in the fluctuating patterns of COD (chemical oxygen demand) during the treatment of palm oil mill effluent (POME) using pilot scale triple frequency ultrasound cavitation reactor, Ultrason. Sonochem., 21 (2014) 1519–1526.
  13. K.Y. Show, L.P. Wong, Application of Ultrasound Pretreatment for Sludge Digestion, A. Mudhoo, ed., Biogas Production: Pretreatment Methods in Anaerobic Digestion, Scrivener Publishing LLC, United States of America, 2012, pp. 91–136.
  14. S. Parthasarathy, R.R. Mohammed, C.M. Fong, R.L. Gomes, S. Manickam, A novel hybrid approach of activated carbon and ultrasound cavitation for the intensification of palm oil mill effluent (POME) polishing, J. Clean. Prod., 112 (2016) 1218–1226.
  15. G. Erden, N. Buyukkamaci, A. Filibeli, Effect of low frequency ultrasound on anaerobic biodegradability of meat processing effluent, Desalination, 259 (2010) 223–227.
  16. J.G. Garcia, V. Saez, I. Tudela, M.I.D. Garcia, M.D. Esclapez, O. Louisnard, Sonochemical treatment of water polluted by chlorinated organocompounds: a review, Water, 2 (2010) 28–74.
  17. APHA, Standard Methods for the Examination of Water and Wastewater, 21st ed., American Public Health Association, Washington, D.C., 2005.
  18. P.E. Poh, W.J. Yong, M.F. Chong, Palm oil mill effluent (POME) characteristic in high crop season and the applicability of highrate anaerobic bioreactors for the treatment of POME, Ind. Eng. Chem. Res., 49 (2010) 11732–11740.
  19. N. Saifuddin, S.A. Fazlili, Effect of microwave and ultrasonic pretreatments on biogas production from anaerobic digestion of palm oil mill effluent, Am. J. Eng. Appl. Sci., 2 (2009) 139–146.
  20. T. Mao, K.Y. Show, Influence of ultrasonication on anaerobic bioconversion of sludge, Water Environ. Res., 79 (2007) 436–441.
  21. A. Tiehm, K. Nickel, M. Zellhorn, U. Neis, Ultrasonic waste activated sludge disintegration for improving anaerobic stabilization, Water Res., 35 (2001) 2003–2009.
  22. R. Dewil, J. Baeyens, R. Goutvrind, The use of ultrasonics in the treatment of waste activated sludge, Chin. J. Chem. Eng., 14 (2006) 105–113.
  23. R.A. Alrawi, N.N.N. Ab Rahman, A. Ahmad, N. Ismail, A.K. Mohd Omar, Characterization of oily and non-oily natural sediments in palm oil mill effluent, J. Chem., 2013 (2013) 1–11.
  24. J. Luo, Z. Fang, R.L, Smith Jr., Ultrasound-enhanced conversion of biomass to biofuels, Prog. Energy Combust. Sci., 41 (2014) 56–93.
  25. M. Simonetti, G. Rossi, V. Cabbai, D. Goi, Experimental Tests of Ultrasonic Pre-treatment on Organic Fractions for Anaerobic Co-digestion, Third International Symposium on Energy from Biomass and Waste, 8–11 November, Venice, Italy, 2010.
  26. K.Y. Show, T. Mao, D.J. Lee, Optimisation of sludge disruption by sonication, Water Res., 41 (2007) 4741–4747.
  27. C.P. Chu, B.-V. Chang, G.S. Liao, D.S. Jean, D.J. Lee, Observations on changes in ultrasonically treated waste-activated sludge, Water Res., 35 (2001) 1038–1046.
  28. L.-P. Wong, M.H. Isa, M.J.K. Bashir, Disintegration of palm oil mill effluent organic solids by ultrasonication: optimization by response surface methodology, Process Saf. Environ. Prot., 114 (2018) 123–132.