Surrounding System Implications on the Environmental Performance of Sewage Sludge SCWO
Svanströma, M.1, Fröling,M.1 and Tester, J.W.2
1Chalmers University of Technology, Sweden, 2Massachusetts Institute of Technology, USA
(free)
The total environmental performance of supercritical water oxidation (SCWO) and other advanced oxidation technologies for
waste treatment have been shown to be highly dependant on up- and downstream activities. Energy and chemicals needed
for the processes involved often bring a considerable environmental cost from source processes needed to produce them.
Beneficial use of recovered products can bring considerable environmental gains, sometimes making up for all environmental
loads associated with the processes involved and upstream activities. Life cycle assessment (LCA) methodology was used
to study the environmental systems performance of sewage sludge SCWO. The SCWO process under study offers the
possibility of recovery of both heat and phosphorus as well as other inorganic products from sewage sludge. Environmental
implications of up- and downstream activities are discussed and highlighted by examples. When the considered energy
system or the type of chemicals used are
type of chemicals used is varied, this influences greatly the total environmental
performance of the system.
KEYWORDS
Energy recovery, hydrothermal oxidation, LCA, life cycle assessment, phosphorus recovery, SCWO, sewage sludge,
supercritical water oxidation
