American Institute of Aeronautics and Astronautics
1
Pyrolysis Yields from Microwave-Assisted Heating of Solid
Wastes
Michael A. Serio
1
, Joseph E. Cosgrove
2
, and Marek A. Wójtowicz
3
Advanced Fuel Research, Inc., 87 Church Street, East Hartford, CT 06108-3728 USA
Kanapathipillai Wignarajah
4
and John Fisher
5
NASA Ames Research Center, Moffett Field, CA 94035-1000 USA
This paper continues previous work on pyrolysis processing of solid wastes for spacecraft
and planetary surface applications. A domestic microwave oven was modified for use in this
work for scoping studies in which the effects of sample composition, use of central
microwave absorbers, and secondary pyrolysis of liquids were studied. Experiments were
done with wheat straw and various formulations of a feces simulant. The microwave
absorbers examined included activated carbon and char produced from previous
experiments. The addition of a separate microwave-heated secondary pyrolysis zone was
also examined as a means of reducing the liquid product yields. In general, the feces
simulants had similar pyrolysis yields when compared to wheat straw for the char and total
gas yields, but individual gas yields were different. For example, the feces simulants
produced significantly more ethylene, larger amounts of methane, and smaller amounts of
carbon oxides (CO + CO
2
). This can be largely explained by the differences in elemental
compositions. A comparison was also made of the microwave-assisted pyrolysis of feces
simulants of variable moisture contents (0-60 wt. %). The higher moisture contents (40-60
wt. %) result in a delay for the onset of pyrolysis and a higher energy demand per gram of
sample, as might be expected. However, at lower moisture contents, such as the 20 wt. %
water for the baseline sample, it was found that the overall energy demand appeared to be
lower than for the dried sample, perhaps due to the more efficient absorption of microwave
energy.
Nomenclature
CELSS = Controlled Ecological Life Support System (CELSS)
DAF = Dry, Ash-Free
ESM = Equivalent System Mass
FC = Fixed Carbon
FTIR = Fourier Transform Infrared
HHV = Higher Heating Value
ISRU = In-Situ Resource Utilization
MAP = Microwave-Assisted Pyrolysis (MAP)
MFM = Mass Flow Meter
VM = Volatile Matter
1
President, Advanced Fuel Research, Inc. (AFR), 87 Church Street, East Hartford, CT 06108.
2
Laboratory Manager, AFR, 87 Church Street, East Hartford, CT 06108.
3
Vice President, Clean Energy & Carbon Materials, AFR, 87 Church Street, East Hartford, CT 06108.
4
Senior Scientist, SCB Branch, MS 239-8, NASA-Ames Research Center, Moffett Field, CA 94035.
5
Lead Engineer, Exploration Life Support, NASA-Ames Research Center, Moffett Field, CA 94035.
42nd International Conference on Environmental Systems
15 - 19 July 2012, San Diego, California
AIAA 2012-3566
Copyright © 2012 by Advanced Fuel Research, Inc. Published by the American Institute of Aeronautics and Astronautics, Inc., with permission.
Downloaded by Michael Serio on September 17, 2013 | http://arc.aiaa.org | DOI: 10.2514/6.2012-3566