Sludge as a potential feedstock for thermochemical conversion a comprehensive characteristics study

Municipal wastewater sludge handling and disposal has become a more and more challenging issue in both developed and developing countries. Sludge production is expected to grow while regulations on sludge disposal have been tightened due to concerns with its high toxicity. In the recent years, energ...

Full description

Bibliographic Details
Main Author: Chen, Rong Fen
Other Authors: Wang Jing-Yuan
Format: Final Year Project (FYP)
Language:English
Published: 2015
Subjects:
Online Access:http://hdl.handle.net/10356/64094
_version_ 1826117462619324416
author Chen, Rong Fen
author2 Wang Jing-Yuan
author_facet Wang Jing-Yuan
Chen, Rong Fen
author_sort Chen, Rong Fen
collection NTU
description Municipal wastewater sludge handling and disposal has become a more and more challenging issue in both developed and developing countries. Sludge production is expected to grow while regulations on sludge disposal have been tightened due to concerns with its high toxicity. In the recent years, energy and material recovery of sludge via thermochemical conversions has attracted much attention in the scientific world. Performance of thermochemical conversions of sludge is largely dependent on the feedstock quality. Thus, comprehensive study of characteristics of sludge is a key component to thermochemical conversion of sludge. This report intended to investigate the characteristics of sludge in Singapore as a feedstock for thermochemical conversion. The characteristics study was done in three aspects, namely, inherent characteristics of sludge, biomass compositions of sludge and pyrolytic behaviors of sludge. Sludge samples of different types and batches from the same water reclamation plant were used in this report for comparisons of sludge characteristics across types and batched. Pelletized density, higher heating value (HHV), ultimate analysis and functional group analysis were performed to understand the properties of sludge mixture as received. Sequential extractions of sludge were conducted using ethanol and water as solvents in an attempt to gain a more insightful view of the possible biomass compositions in sludge. Thereafter, HHV, ultimate analysis and functional group analysis of the extraction residues and extractives were carried out. Sludge samples were placed for pyrolytic conversions under pre-set conditions followed by analysis on the product compositions. Pyrolytic product gases were further studied using gas chromatography where product chars were analyzed with calorific test, ultimate analysis and functional group identifications. In terms of inherent characteristics and biomass composition analysis, sludge samples of different types produced deviating properties in general whereas sludge samples of different batches showed close proximity. Nevertheless, consistent relative trends in the dry base HHV, CHNS compositions and functional group identifications among different types were observed. The analysis of the pyrolytic product compositions, on the other hand, indicated that both lower ash content and higher process temperature resulted in higher non-solid product composition and higher proportion of H2 and organic hydrocarbon gases liberated. Study of the functional groups present in chars obtained from different temperature depicted a trend in the relative ease of thermal conversion of certain functional groups.
first_indexed 2024-10-01T04:27:59Z
format Final Year Project (FYP)
id ntu-10356/64094
institution Nanyang Technological University
language English
last_indexed 2024-10-01T04:27:59Z
publishDate 2015
record_format dspace
spelling ntu-10356/640942023-03-03T17:04:48Z Sludge as a potential feedstock for thermochemical conversion a comprehensive characteristics study Chen, Rong Fen Wang Jing-Yuan School of Civil and Environmental Engineering Residues and Resource Reclamation Centre DRNTU::Engineering::Environmental engineering::Water treatment Municipal wastewater sludge handling and disposal has become a more and more challenging issue in both developed and developing countries. Sludge production is expected to grow while regulations on sludge disposal have been tightened due to concerns with its high toxicity. In the recent years, energy and material recovery of sludge via thermochemical conversions has attracted much attention in the scientific world. Performance of thermochemical conversions of sludge is largely dependent on the feedstock quality. Thus, comprehensive study of characteristics of sludge is a key component to thermochemical conversion of sludge. This report intended to investigate the characteristics of sludge in Singapore as a feedstock for thermochemical conversion. The characteristics study was done in three aspects, namely, inherent characteristics of sludge, biomass compositions of sludge and pyrolytic behaviors of sludge. Sludge samples of different types and batches from the same water reclamation plant were used in this report for comparisons of sludge characteristics across types and batched. Pelletized density, higher heating value (HHV), ultimate analysis and functional group analysis were performed to understand the properties of sludge mixture as received. Sequential extractions of sludge were conducted using ethanol and water as solvents in an attempt to gain a more insightful view of the possible biomass compositions in sludge. Thereafter, HHV, ultimate analysis and functional group analysis of the extraction residues and extractives were carried out. Sludge samples were placed for pyrolytic conversions under pre-set conditions followed by analysis on the product compositions. Pyrolytic product gases were further studied using gas chromatography where product chars were analyzed with calorific test, ultimate analysis and functional group identifications. In terms of inherent characteristics and biomass composition analysis, sludge samples of different types produced deviating properties in general whereas sludge samples of different batches showed close proximity. Nevertheless, consistent relative trends in the dry base HHV, CHNS compositions and functional group identifications among different types were observed. The analysis of the pyrolytic product compositions, on the other hand, indicated that both lower ash content and higher process temperature resulted in higher non-solid product composition and higher proportion of H2 and organic hydrocarbon gases liberated. Study of the functional groups present in chars obtained from different temperature depicted a trend in the relative ease of thermal conversion of certain functional groups. Bachelor of Engineering (Environmental Engineering) 2015-05-25T01:43:11Z 2015-05-25T01:43:11Z 2015 2015 Final Year Project (FYP) http://hdl.handle.net/10356/64094 en Nanyang Technological University 60 p. application/pdf
spellingShingle DRNTU::Engineering::Environmental engineering::Water treatment
Chen, Rong Fen
Sludge as a potential feedstock for thermochemical conversion a comprehensive characteristics study
title Sludge as a potential feedstock for thermochemical conversion a comprehensive characteristics study
title_full Sludge as a potential feedstock for thermochemical conversion a comprehensive characteristics study
title_fullStr Sludge as a potential feedstock for thermochemical conversion a comprehensive characteristics study
title_full_unstemmed Sludge as a potential feedstock for thermochemical conversion a comprehensive characteristics study
title_short Sludge as a potential feedstock for thermochemical conversion a comprehensive characteristics study
title_sort sludge as a potential feedstock for thermochemical conversion a comprehensive characteristics study
topic DRNTU::Engineering::Environmental engineering::Water treatment
url http://hdl.handle.net/10356/64094
work_keys_str_mv AT chenrongfen sludgeasapotentialfeedstockforthermochemicalconversionacomprehensivecharacteristicsstudy