dc.contributor.advisor |
Parker, Alison |
|
dc.contributor.advisor |
Cartmell, Elise |
|
dc.contributor.author |
Rose, Christopher |
|
dc.date.accessioned |
2016-06-21T08:45:25Z |
|
dc.date.available |
2016-06-21T08:45:25Z |
|
dc.date.issued |
2015-06 |
|
dc.identifier.uri |
http://dspace.lib.cranfield.ac.uk/handle/1826/9984 |
|
dc.description.abstract |
It is estimated that 2.7 billion people worldwide are served by on-site sanitation
facilities that require faecal sludge management. Anaerobic digestion is a
treatment mechanism that can provide faecal sludge management, methane
production and an effluent digestate rich in nutrients. However, there is a
paucity of information regarding the composition of the input faecal sludge
which hinders the advancement of anaerobic digestion treatment and
downstream nutrient recovery together with a lack of knowledge as to how best
to recover these output nutrients in a simple process.
Following an initial review to collate composition data for fresh faeces and urine,
practical studies examined the physical, biological and chemical composition
and variation of four different types of faecal sludge from on-site sanitation
facilities. Faecal sludge storage strongly influenced the biodegradability and
methane production potential in subsequent anaerobic digestion. However, the
high concentrations of ammonium observed in faecal sludge (520-1853 mg
NH4-N L-
1
) were highlighted as a key goal for nutrient recovery and the ability of
biochar and clinoptilolite as natural adsorbents for ammonium recovery in a
drying bed application were investigated through batch and dynamic studies
using synthetic and real digestate. Batch tests observed ammonium uptake of 5
and 12.2 mg NH4-N/g for biochar and clinoptilolite respectively whilst under
dynamic experimental conditions the most efficient operation for ammonium
recovery was at the longest empty bed contact times (354 minutes), ensuring
the maximum fertiliser value was obtained (60g NH4-N/kg clinoptilolite).
Nevertheless, clogging occurred rapidly at the surface of the media bed (0.04 –
0.5 kg TS/m2 ), consequently a sacrificial sand layer (0.05 m) was included to
increase the longevity of the nutrient recovery system (15 fold increase in TS
application rates). It has been demonstrated that clinoptilolite can effectively be
used as part of a sludge drying bed configuration to recover nutrients from
digestate and the saturated media can be used directly as a fertiliser product or
blended with the dried sludge to create a balanced nitrogen, phosphorus and
potassium fertiliser product (5.9% NH4-N/ 4.2% P/ ≥6.0% K+ ). |
en_UK |
dc.language.iso |
en |
en_UK |
dc.publisher |
Cranfield University |
en_UK |
dc.rights |
© Cranfield University, 2015. All rights reserved. No part of this publication may be reproduced without the written permission of the copyright holder. |
en_UK |
dc.title |
Developing a nutrient recovery process for recovering nutrients in anaerobic digestate in low income countries |
en_UK |
dc.type |
Thesis or dissertation |
en_UK |
dc.type.qualificationlevel |
Doctoral |
en_UK |
dc.type.qualificationname |
PhD |
en_UK |