Municipal wastewater sludge as a sustainable bioresource in the United States.

Within the United States and Puerto Rico, publicly owned treatment works (POTWs) process 130.5 Gl/d (34.5 Bgal/d) of wastewater, producing sludge as a waste product. Emerging technologies offer novel waste-to-energy pathways through whole sludge conversion into biofuels. Assessing the feasibility, scalability and tradeoffs of various energy conversion pathways is difficult in the absence of highly spatially resolved estimates of sludge production. In this study, average wastewater solids concentrations and removal rates, and site specific daily average influent flow are used to estimate site specific annual sludge production on a dry weight basis for >15,000 POTWs. Current beneficial uses, regional production hotspots and feedstock aggregation potential are also assessed. Analyses indicate 1) POTWs capture 12.56 Tg/y (13.84 MT/y) of dry solids; 2) 50% are not beneficially utilized, and 3) POTWs can support seven regions that aggregate >910 Mg/d (1000 T/d) of sludge within a travel distance of 100 km.

[1]  George Tchobanoglous,et al.  Wastewater Engineering: Treatment and Resource Recovery , 2013 .

[2]  Sally Brown,et al.  Calculator tool for determining greenhouse gas emissions for biosolids processing and end use. , 2010, Environmental science & technology.

[3]  Izrail S. Turovskiy,et al.  Wastewater Sludge Processing , 2006 .

[4]  D S Mavinic,et al.  Wastewater biosolids: an overview of processing, treatment, and management , 2001 .

[5]  M. Azuara,et al.  Sewage sludge pyrolysis for liquid production: A review , 2012 .

[6]  R. Bastian.  The biosolids (sludge) treatment, beneficial use, and disposal situation in the USA , 1997 .

[7]  Susanne B. Jones,et al.  Hydrothermal liquefaction of biomass: developments from batch to continuous process. , 2015, Bioresource technology.

[8]  Jeonghwan Kim,et al.  Domestic wastewater treatment as a net energy producer--can this be achieved? , 2011, Environmental science & technology.

[9]  P. Jeníček,et al.  Thermophilic versus Mesophilic Anaerobic Digestion of Sewage Sludge: A Comparative Review , 2016, Bioengineering.

[10]  R. Riffat.  Fundamentals of Wastewater Treatment and Engineering , 2012 .

[11]  Nandakishore Rajagopalan,et al.  Chemical and biological characterization of wastewater generated from hydrothermal liquefaction of Spirulina. , 2013, Environmental science & technology.

[12]  John W. Scott,et al.  Chemical properties of biocrude oil from the hydrothermal liquefaction of Spirulina algae, swine manure, and digested anaerobic sludge. , 2011, Bioresource technology.

[13]  Paul Westerhoff,et al.  We Should Expect More out of Our Sewage Sludge. , 2015, Environmental science & technology.

[14]  Kevin G. Robinson,et al.  Public attitudes and risk perception toward land application of biosolids within the south-eastern United States. , 2012, Journal of environmental management.

[15]  Jing Liu,et al.  Effects of solid retention time on anaerobic digestion of dewatered-sewage sludge in mesophilic and thermophilic conditions , 2010 .