Mixed municipal solid waste currently landfilled contains a high percentage of packaging glass, varying from 33% to 80% by weight according to several sample characterizations, due to the lack of high throughput separation technology. The hydrodynamic separator proposed is a closed-loop device developed to separate co-mingled waste into plastics, glass and other dense particles and organic sludge. The glass and other dense material stream is cleaned by the system, permitting efficient downstream optical sorting to take out metals and ceramics and, if required, glass sorted by colour. The plastics and the organic sludge are separate, processable waste streams. As the solid waste is introduced in the separator, the action of water jets located on the ramps of a fixed sinusoidal-shape bottom and the presence of hydrofoils at the upper part of the tank produce a flow pattern that lead plastics towards its collection point on the surface, while glass and ceramics are settled to the bottom of the tank and transported to the extraction point. Organics and other fine particles are obtained from lamellas, before reintroducing the clarified fluid into the flow loop. The sludge obtained from this process is suitable for feedstock to Anaerobic Digestion processes. In the present paper the equipment and the methodology is described and the physical principles of the separation process are explained. Results from a full scale trial designed to process 9.7 tonnes per hour at a municipal UK waste site operating in Nov 2015 – Feb 2016 are presented.
co-mingled, fluid-dynamics, glass, plastic, recycling, separation, turbulence
 Study on total waste management of Jimma southern Ethiopia, LEM: the Environment & Development Society of Ethiopia, 2006.
 Williams, M., Waste-to-energy success factors in Sweden and the United States. Analyzing the transferability of the Swedish waste-to-energy model to the United States, 2011.
 Digest of Waste and Resource Statistics – 2015 Edition, U.K. Department for Environment Food & Rural Affairs. PB14292 Online, availbale at https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/482255/Digest_of_waste_England_-_finalv3.pdf
 Hoerner, S., Fluid-Dynamic Drag, 2nd edn., Published by the author: Midland Park, N.J, 1965.
 Hölzer, A. & Sommerfeld, M., New simple correlation formula for the drag coefficient of non-spherical particles. Powder Technology. 184, pp 361–365, 2008. http://dx.doi.org/10.1016/j.powtec.2007.08.021
 Gabito, J. & Tsouris, C., Drag coefficient and settling velocity for particles of cylindrical shape. Powder Technology, 183, pp. 314–322, 2008. http://dx.doi.org/10.1016/j.powtec.2007.07.031
 Zhang, H., Ahmadi, G., Fan, F. & McLaughlin, J., Ellipsoidal particles transport and deposition in turbulent channel flows. International Journal of Multiphase Flow, 27(6), pp. 971–1009, 2001. http://dx.doi.org/10.1016/S0301-9322(00)00064-1
 Stringham, G.E., Simons, D.B. & Guy, H.P., The behaviour of Large Particles Falling in Quiescent Liquids. Sediment Transport in Alluvial Channels. Geological Survey Professional Paper 562-C, 1969.
 Fornari, W., Picano, F., & Brandt, L., Sedimentation of finite-size spheres in quiescent and turbulent environments. Journal of Fluid Mechanics, 788, pp. 640–669, 2016. http://dx.doi.org/10.1017/jfm.2015.698
 Yang, C.Y. & Lei, U., The role of turbulent scales in the settling velocity of heavy particles in homogeneous isotropic turbulence. Journal of Fluid Mechanics, 371, pp. 179–205, 1998. http://dx.doi.org/10.1017/S0022112098002328
 Tanaka, T. & Eaton, J.K., Sub-Kolmogorov resolution particle image velocimetry measurements of particle-laden forced turbulence. Journal of Fluid Mechanics, 643, pp. 177–206, 2010. http://dx.doi.org/10.1017/S0022112009992023
 Yang, T.S. & Shy, S.S., The settling velocity of heavy particles in an aqueous near-isotropic turbulence. Physics of Fluids, 15(4), pp. 868–880, 2003. http://dx.doi.org/10.1063/1.1557526
 Gore, R.A. & Crowe, C.T., Effect of particle size on modulating turbulent intensity. International Journal of Multiphase Flow, 15(2), pp. 279–285, 1989. http://dx.doi.org/10.1016/0301-9322(89)90076-1
 Elghobashi, S. & Truesdell, G.C., On the two-way interaction between homogeneous turbulence and dispersed solid particles. I: Turbulence modification. Physics of Fluids, 5, pp. 1790–1801, 1993. http://dx.doi.org/10.1063/1.858854
 Balachandar, S. & Eaton, J.K., Turbulent dispersed multiphase flow. Annual Reviews Fluid Mechanics, 42, pp. 111–133, 2010. http://dx.doi.org/10.1146/annurev.fluid.010908.165243
 Aquavitrum Ltd, CDPA 1988 patent no: GB2512270 & patent pending no: GB1412552.0, 2013.
 Pope, S.B., Turbulent Flows, Cambridge University Press, 2000. http://dx.doi.org/10.1017/CBO9780511840531