(703e) Application of a Hydrocyclone for Sludge Processing in a Wastewater Treatment Plant

In municipal wastewater treatment plants (WWTP) anaerobic digesters are commonly used for the stabilization of organic components before sludge thickening. In the digestion process biogas is produced which is used for operating a combined heat and power plant [1]. For optimizing the biogas production biological waste is often added as a co-substrate in the fermentation process. The primary sludge and the biowaste often contain particulate impurities (e.g. sand, glass, metal). These particles cause high operational costs due to enhanced attrition of pumps and particle sedimentation in the anaerobic digester [2].

For a selective removal of particles from the sludge a hydrocyclone can be installed in the process. The literature provides comparatively few information on this field of application of hydrocyclones [3-5]. For this reason an empirical optimization of geometrical and operational parameters was performed within the last 4 years in the project [6-8].

The present work presents the optimized hydrocyclone, the operation mode and first results (separation efficiency and pressure drop) of the field tests at the WWTP.

[1] Henze, M., Harremoes, P., la Cour Jansen, J., Arvin, E., Wastewater Treatment – Biological and Chemical Processes, Springer, 2002.

[2] Jank, A., Müller, W., Waldhuber, S., Gerke, F., Ebner, C., Bockreis, A., Impurities in pretreated biowaste for co-digestion: A determination approach, Waste Management, 52, 96-103, 2016.

[3] Mansour-Geoffrion, M., Dold, P.L., Lamarre, D., Gadbois, A., Déléris, S., Comeau, Y., Characterizing hydrocyclone performance for grit removal from wastewater treatment activated sludge plants, Minerals Engineering, 23, 359-364, 2010.

[4] Bayo, J., López-Castellanos, J., Martínez-García, R., Alcolea, A., Lardín, C., Hydrocyclone as a cleaning device for anaerobic sludge digesters in a wastewater treatment plant, Journal of Cleaner Production, 87, 550-557, 2015.

[5] Bicalho, I.C., Mognon, J.L., Shimoyama, J., Ataíde, C.H., Duarte, C.R., Separation of yeast from alcoholic fermentation in small hydrocyclones, Separation and Purification Technology, 87, 62-70, 2012.

[6] Senfter, T., Pillei, M., Bockreis, A., Rauch, W. and Kraxner, M., Experimental Study on the Velocity Distribution in a Hydrocyclone with a Highly Viscous Fluid, AIChE - American Institute of Chemical Engineers - Annual Meeting, San Francisco / California USA, 2016.

[7] Senfter, T., Pillei, M., Berger, M., Bockreis, A., Rauch, W. und Kraxner, M., Hydrocyclone Optimization for the Removal of Impurities in Biowaste Co-digestion Processes, 18th International Conference Transport & Sedimentation of Solid Particles, Prague CZ, 2017.

[8] Senfter, T., Pillei, M., Berger, M., Bockreis, A., Rauch, W. and Kraxner M., Influence of the Viscosity on the Velocity Propagation in Axial Direction in a Rietema Hydrocyclone, AIChE - American Institute of Chemical Engineers - Annual Meeting, Minneapolis USA, 2017.