Atomized sludges via spray-drying at low temperatures: an alternative to conventional wastewater treatment plants.

Removal of sludges from Wastewater Treatment Plants (WWTP) represents a serious worldwide environmental problem for which alternatives other than their simple incineration are investigated. In this work the treatment of raw sludge from urban WWTP by means of a minimization process through spray-drying is analyzed as well as some proposals for revaluating the resulting dry product. Analysis is supported by some experimental results obtained with a laboratory spray dryer. The experimental procedure at laboratory scale is extrapolated to an industrial plant scale. An economic analysis of the proposal in relation to other possible sludge treatments is presented, taking into account in this case the comparison between the costs of the processes of sludge thickening, stabilization and dehydratation and the costs of spray-drying (especially power consumption), minimization of the final waste and reuse options. Finally, an environmental balance of the process is presented. In contrast with the classical treatment line, this alternative allows transforming sludges, i.e., a waste, into a valuable product with several applications.

[1]  Patricia Arlabosse,et al.  Identification of the Limiting Mechanism in Contact Drying of Agitated Sewage Sludge , 2007 .

[2]  Angélique Léonard,et al.  Sustainable and innovative solutions for sewage sludge management. , 2011 .

[3]  J. Cusidó,et al.  Gaseous emissions from ceramics manufactured with urban sewage sludge during firing processes. , 2003, Waste management.

[4]  Arun S. Mujumdar,et al.  Thermal Drying Technologies—Cost-Effective Innovation Aided by Mathematical Modeling Approach , 2007 .

[5]  Arun S. Mujumdar,et al.  SLUDGE DEWATERING AND DRYING , 2002 .

[6]  Don W. Green,et al.  Perry's Chemical Engineers' Handbook , 2007 .

[7]  W. A. Amos,et al.  Report on Biomass Drying Technology , 1999 .

[8]  J. Vaxelaire,et al.  Incineration of a small particle of wet sewage sludge: a numerical comparison between two states of the surrounding atmosphere. , 2007, Journal of hazardous materials.

[9]  Daniel Mamais,et al.  Alternative schemes for the management of the sludge produced at Psyttalia WWTP , 2000 .

[10]  Tom M. Pankratz Advances in desalination technology , 2005 .

[11]  E. Vázquez,et al.  Leaching properties of stabilised/solidified cement-admixtures-sewage sludges systems. , 2002, Waste management.

[12]  J. Werther,et al.  Sewage sludge combustion , 1999 .

[13]  Nebel Bernard,et al.  Ciencias ambientales: ecología y desarrollo sostenible , 1999 .

[14]  Wan Ramli Wan Daud,et al.  Optimization of the Spray Drying Operating Parameters—A Quick Trial-and-Error Method , 2007 .

[15]  John T. Novak,et al.  Dewatering of Sewage Sludge , 2006 .

[16]  L. F. Calvo,et al.  Kinetic and equilibrium modelling of the methylene blue removal from solution by adsorbent materials produced from sewage sludges , 2003 .