dc.contributor.author | Asamany, Ebenezer Afram | |
dc.date.accessioned | 2017-01-05T13:49:15Z | |
dc.date.available | 2017-01-05T13:49:15Z | |
dc.date.issued | 2017-01-05T13:49:15Z | |
dc.identifier.uri | http://hdl.handle.net/10222/72616 | |
dc.description.abstract | Co-processing waste as alternative fuel in cement kilns presents a two-pronged solution to
cost and environmental concerns in resource utilization. It is the simultaneous recovery of
energy and recycling of resources where waste from different sources are used in the manufacture
of a valuable commodity such as cement. In this study, bench-scale and full-scale
experiments have been used to identify and characterize examples of waste-derived fuels
(WDF) available for co-processing in cement kilns in Nova Scotia, Canada.
Field trials were used to select optimum kiln delivery approaches which overcame practical
operational challenges in the delivery of waste asphalt roofing shingles (WARS) into the
local cement kiln. The consumption of shingles was improved from 5% to 17% by mass of
total fuel combusted.
A bench-scale tube furnace was used to determine the volatile organic compounds (VOC)
content and particle distribution of combustion products generated from WDF. Plastic-derived
fuel (PDF) from low density polyethylene (LDPE) film, plastic containers and expanded
polystyrene (EPS) were found to have better thermal performance compared to
waste carpets and discarded clothing on an equivalent energy basis. With respect to calorific
value, moisture content and ash content of the WDF, thermal performance indicators,
observed in full-scale tests, such as clinker production rate, kiln gas flowrate and kiln gas
temperature matched bench-scale trends in residual VOC emission from the combustion of
WDF.
A heated grid reactor (HGR) was designed and constructed, and then used in conjunction
with Thermogravimetric analysis (TGA) and emission measurements, in several combustion
experiments on waste plastics, waste shingles and blends with coal and coke. Particulate
emissions sampled from the combustion of the fuel blends containing WDF did not
differ significantly from that of the mixture of coal and coke only. Indeed, blending with
plastics and shingles was seen to improve the combustion efficiency by reducing the time
to ignition (TTI) and the extent of devolatilization achieved in the coal and coke fuel samples
over a 5 to 10 second fast heating period.
Using these experiments, a bench-scale screening procedure for WDF to be used as cement
kiln fuel was applied to study, assess and to provide preliminary expectations for WDF
application in a local cement kiln. The results also showed that the proper co-processing of
WDF in Nova Scotia will not only result in macro-scale environmental gains, but also improve
the efficiency of the combustion process on a micro level without significantly affecting
particulate emissions. | en_US |
dc.language.iso | en | en_US |
dc.subject | alternative fuels | en_US |
dc.subject | energy recovery | en_US |
dc.subject | waste diversion | en_US |
dc.subject | combustion | en_US |
dc.subject | co-processing | en_US |
dc.subject | Waste products as fuel | |
dc.title | WASTE-DERIVED FUELS FOR CO-PROCESSING IN ROTARY CEMENT KILNS | en_US |
dc.date.defence | 2016-11-14 | |
dc.contributor.department | Department of Process Engineering and Applied Science | en_US |
dc.contributor.degree | Doctor of Philosophy | en_US |
dc.contributor.external-examiner | William Hallett | en_US |
dc.contributor.graduate-coordinator | Adam Donaldson | en_US |
dc.contributor.thesis-reader | Donald Jones | en_US |
dc.contributor.thesis-reader | Jan Haelssig | en_US |
dc.contributor.thesis-supervisor | Michael J. Pegg | en_US |
dc.contributor.thesis-supervisor | Mark D. Gibson | en_US |
dc.contributor.ethics-approval | Not Applicable | en_US |
dc.contributor.manuscripts | No | en_US |
dc.contributor.copyright-release | No | en_US |