Extensive experimental investigations were carried out to evaluate the rheological behaviour of fly ash (FA) slurry without and with the addition of bottom ash (BA) and BA slurry without and with the addition of FA. The FA slurries exhibited Bingham behaviour at solid mass concentrations ranging from 60–65% and mixing proportions from 10– 40%. A substantial reduction in yield stress was observed except for mixing proportion of 40% on which the yield stress and viscosity were increased drastically for all solid concentrations. Hence, it can be concluded that the yield stress and viscosity of FA slurry were very much influenced by adding BA up to the mixing proportion of 30%. The rheological behaviour of BA slurries with and without the addition of FA in proportions of 10–50% was investigated and exhibited Newtonian behaviours for solid mass concentrations ranging from 30–50% without and with the addition of FA. The viscosity increases with increasing the solid concentrations and proportion of FA. Based on these experimental data, a correlation was developed to predict the relative viscosity of BA slurries as a function of solid volume fraction and FA mass proportion of 0–50% and the RMSE and R2 values showed good agreement between the experimental and the predicted data.
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Biswas A. Gandhi B.K. Singh S.N. Seshadri V. 2000. Characteristics of coal ash and their role in hydraulic design of ash disposal pipelines. Indian Journal of Engineering and Material Science 7 1–7.
Chandel S. Seshadri V. Singh S.N. 2009a. Effect of additive on pressure drop and rheological characteristics of fly ash slurry at high concentration. Particulate Science and Technology 27 3 271–284.
Chandel S. Singh S.N. Seshadri V. 2009b. Deposition characteristics of coal ash slurries at higher concentrations. Advanced Powder Technology 20 383–389.
Chandel S. Seshadri V. Singh S.N. 2010. Transportation of high concentration coal ash slurries through pipelines. Inter. Archive of Applied Science and Technology 1 1 1–9.
Chong J.S. Christiansen E.B. Baer A.D. 1971. Rheology of concentrated suspensions. Journal of Applied Polymer Science 15 2007–2021.
Gahlot V.K. Seshadri V. Malhotra R.C. 1988. A method for the experimental determination of the rheological parameters of multisized course particulate slurries. In: Inter. Symposium on Hydraulic Transportation of Coal and Other Minerals IIT Delhi March 4–6 pp. 283–295.
Kolar V. Pollert J. Sellin R.H.J. Vlasak P. 1988. Experiment with drag reducing polymer in an ash-slag hydro transport pipeline. Journal of Hydraulic Research 26 2 143–158.
Kunal S. Kundan L. 2012. Effect of Cetylpyridinium chloride Triton x-100 and Sodium Dodecyl Sulphate on rheology of fly ash slurry. International Journal of Scientific and Research Publications 2 8 1–5.
Mosa S. Abdel H.M.S. Taha A. Anas M.E. 2008. Effect of chemical additives on flow characteristics of coal slurries. J. of Physicochemical Problems of Mineral Processing 42 107–118.
Naik H.K. Mishra M.K. Rao Karanam U.M. Deb D. 2009a. Evaluation of the role of a cationic surfactant on the flow characteristics of fly ash slurry. Journal of Hazardous Materials 169 1134–1140.
Naik H.K. Mishra M.K. Rao Karanam U.M. 2009b. The effect of drag reducing additives on the rheological properties of fly ash-water suspensions at varying temperature environment. Coal Combustion and Gasification Products 1 25–31.
Naik H.K. Mishra M.K. Rao K.U.M. 2011. Influence of chemical reagents on rheological properties of fly ash – water slurry at varying temperature environment. Coal Combustion and Gasification Products 3 83–93.
Panda D. Pradhan B. 2014. Hydraulic transport of fly ash and fly ash- bottom ash mixtures at high concentrations. International Journal of Chemical Engineering and Applied Sciences 4 1 1–4.
Senapati P.K. Mishra B.K. 2012. Design considerations for hydraulic backfilling with coal combustion products (CCPs) at high solids concentrations. Powder Technology 229 119–125.
Senapati P.K. Mishra B.K. Parida A. 2010. Modeling of viscosity for power plant ash slurry at higher concentrations: Effect of solids volume fraction particle size and hydrodynamic interactions. Powder Technology 197 1–8.
Senapati P.K. Mishra B.K. Parida A. 2013. Analysis of friction mechanism and homogeneity of suspended load for high concentration fly ash & bottom ash mixture slurry using rheological and pipeline experimental data. Powder Technology 250 154–163.
Seshadri V. Singh S.N. Jain K.K. Verma A.K. 2005. Rheology of fly ash slurries at high concentrations and its application to the design of high concentration slurry disposal system (HCSD). In: Proceedings of the International Conference on Fly Ash Utilization 1 10.
Umesh K. Mishra R. Singh S.N. Seshadri V. 2003. Effect of particle gradation on flow characteristics of ash disposal pipelines. Powder Technology 132 39–51.
Verma A.K. Singh S.N. Seshadri V. 2006. Pressure drop for the flow of high concentration solid liquid mixture 90° horizontal conventional circular pipe bends. Indian Journal of Engineering and Material Science 13 477–483.
Vlasak P. Chara Z. 2004. Laminar and turbulent transition of fine-grained slurries. Particulate Science and Technology 22 2 189–200.
Vlasak P. Chara Z. 2009. Conveying of solid particles in Newtonian and non-Newtonian carriers. Particulate Science and Technology 27 5 428–443.
Vlasak P. Chara Z. 2011. Effect of particle size distribution and concentration on flow behaviour of dense slurries. Particulate Science and Technology 29 1 53–65.
Vlasak P. Chara Z. Stern P. 2010. Drag reduction of dense Fine-Grained slurries. Journal of Hydrology and Hydromechanics 58 4 261–270.