Wheatley_Inorganic profiles.pdf (426.74 kB)
Inorganic profiles of chemical phosphorus removal sludge
journal contribution
posted on 2014-07-18, 11:45 authored by Cynthia Carliell-Marquet, Jennifer Smith, Ioannis Oikonomidis, Andrew WheatleyIron dosing is commonly used to remove phosphorus
from wastewater but little is known about how this
changes the distribution of iron, phosphorus, calcium,
magnesium and trace metals in activated and digested
sludge. This research compared the inorganic profiles of
sludge from full-scale processes (activated sludge and
anaerobic digestion) with and without iron dosing, with
the aim of identifying changes in inorganic distribution
resulting from iron dosing. Sludge phosphorus and
metals were fractionated using sequential chemical
extraction. Bioavailable iron was lower in iron-dosed
activated sludge, as was bioavailable phosphorus (6.5 g/kg
compared with 1.8 g/kg), with most of the iron and
phosphorus bound as iron-hydroxy-phosphates. Similar
results were found for anaerobically digested sludge afer
iron dosing; iron and phosphorus in the sludge increased
by 4 and 1.35 times, respectively, but bioavailability was
decreased. The ratio of chemical oxygen demand to
bioavailable phosphorus in the digester was 840 : 1 after
iron dosing. By contrast, calcium, magnesium, copper
and zinc were increasingly bioavailable in the digester
after iron dosing. The reported changes were linked to
the iron content of the sludge; hence the level of iron
dosing is key to minimising changes in sludge inorganic
profiles.
Funding
Results used in this paper are from research funded by EPSRC grants GR/K/96946 and GR/R58550/01; and PGTA funding (Department of Civil Engineering, The University of Birmingham).
History
School
- Architecture, Building and Civil Engineering
Published in
PROCEEDINGS OF THE INSTITUTION OF CIVIL ENGINEERS-WATER MANAGEMENTVolume
163Issue
2Pages
65 - 77 (13)Citation
CARLIELL-MARQUET, C. ... et al, 2010. Inorganic profiles of chemical phosphorus removal sludge. Proceedings of the Institution of Civil Engineers - Water Management, 163(2), pp.65-77.Publisher
ICE PublishingVersion
- VoR (Version of Record)
Publication date
2010Notes
This article was published in the Proceedings of the ICE - Water Management [© ICE Publishing]. Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees. The definitive version is available at: http://dx.doi.org/10.1680/wama.2010.163.2.65ISSN
1741-7589Publisher version
Language
- en