relation: https://khub.utp.edu.my/scholars/16952/ title: Hydrolysis kinetics for solubilizing waste activated sludge at low temperature thermal treatment derived from multivariate non-linear model creator: Liew, C.S. creator: Raksasat, R. creator: Rawindran, H. creator: Kiatkittipong, W. creator: Lim, J.W. creator: Leong, W.H. creator: Lam, M.K. creator: Mohamad, M. creator: Cheng, Y.W. creator: Chong, C.C. description: Low temperature thermal pre-treatment is a low-cost method to break down the structure of extracellular polymeric substances in waste activated sludge (WAS) while improving the sludge biodegradability. However, previous models on low temperature thermal pre-treatment did not adequately elucidate the behaviour of sludge hydrolysis process for the duration ranging from 5 to 9 h. Therefore, this work had developed an inclusive functional model to describe the kinetics of sludge hydrolysis for a wide range of treatment conditions (30 °C�90 °C within 0 and 16 h). As compared with treatment duration, the treatment temperature played a greater impact in solubilizing WAS. Accordingly, the 90 °C treatment had consistently produced WAS with the highest degree of solubility. Nonetheless, the mediocre discrepancies between 90 °C and 75 °C may challenge the practicality of increasing the treatment temperatures beyond 75 °C. The effects of treatment duration on soluble chemical oxygen demand, soluble carbohydrate and soluble protein were only significant during the first 4 h, except for humic substances release that continued to increase with treatment duration. Finally, a good fit with R2 > 0.95 was achieved using an inclusive multivariate non-linear model, substantiating the functionality to predict the kinetics of sludge hydrolysis at arbitrary treatment conditions. © 2021 Elsevier Ltd publisher: Elsevier Ltd date: 2022 type: Article type: PeerReviewed identifier: Liew, C.S. and Raksasat, R. and Rawindran, H. and Kiatkittipong, W. and Lim, J.W. and Leong, W.H. and Lam, M.K. and Mohamad, M. and Cheng, Y.W. and Chong, C.C. (2022) Hydrolysis kinetics for solubilizing waste activated sludge at low temperature thermal treatment derived from multivariate non-linear model. Chemosphere, 292. ISSN 00456535 relation: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85122072682&doi=10.1016%2fj.chemosphere.2021.133478&partnerID=40&md5=51615a6ff5dd10f28f519b03e580e42e relation: 10.1016/j.chemosphere.2021.133478 identifier: 10.1016/j.chemosphere.2021.133478