Transcript utilisation of Municipal Solid Waste (MSW)

‘Hybrid’ biofuels
made from Municipal Solid Waste
and renewable power
D. Mignard and C.L. Pritchard, Institute for Energy Systems
Below: Polar bear in Zoo de La Palmyre
(France). © William Scot, Dec. 2005
Take three major challenges
 Security of fuel supply
 Global warming
 Waste disposal
Take some well known solutions
 Biofuels
 Renewable energies such as wind or marine
 Hydrogen
 Landfilling and, (much better), recycling
TOP: Active tipping
area of an operating
landfill in Perth,
Western Australia
Picture taken by
Ashley Felton, Nov.
2006.
… Find out that they have limitations!
 Land availability, competition with food
crops
 Variability of wind and marine energy could
pose problem on power lines at high
penetration of these sources of energy
 Awkward and energy intensive hydrogen
storage (22 deliveries of compressed
hydrogen needed to replace one petrol
tanker)
 Continued methane emissions from landfill
 Use of high energy value waste, such as
plastics, as filling material (!)
LEFT:
Burning oilfield
during Operation
Desert Storm,
Kuwait (1991).
Picture taken by
Jonas Jordan,
United States
Army Corps of
Engineers
What we are proposing here is a common
solution to Municipal Solid Waste (MSW)
management, the provision of a more CO2neutral alternative to fossil fuels that is truly
sustainable, and reduced dependency on oil.
MSW and renewable energy
Fuel gas to boiler
28.6 t/day
Gas recycle, 2518 t/day
Char, 8.3 t/day
Syngas
MSW,167 t/day
at 10 wt.% moisture
GAS
CLEANING
GASIFIER
Oxygen,
96.3 t/day
Syngas
Oxygen,
71.1 t/day
Methanol, 162 t/day
Water, 1 88.5 t/day
Wind / Marine /
Solar Energy,
1125 MWhe/day
CONDENSER
REACTOR
Electrolysis
plant
Hydrogen,
21.1 t/day
Additional 330 MWhe/day
for compression and gas recycling
Mixed with Water, 40.3 t/day
Distillation
or petrol synthesis
(optional)
Figure 1: Example of ‘hybrid’ process for the production
of transport fuels
Municipal Solid Waste can be a carbon
source for liquid fuels for transport,
including methanol, mixed alcohols,
petrol and diesel. Because it is
deficient in hydrogen for the purpose of
fuel synthesis, and because hydrogen
can be produced from renewable
energies (wind, wave, tidal, solar) via
water electrolysis, we can design
processes that efficiently convert both
MSW and renewable energies to liquid
fuels by combining gasification of MSW
with electrolysis. Figure 1 (left)
presents one such process.
Progress, findings and outcomes so far
• Methanol synthesis should be relatively simple and straightforward to prepare on a large scale, in spite
of the variability of renewable energy sources.
• More work required for synthesis of mixed alcohols (which would be safer than methanol if used by the
general public) - this is the next phase of our work in laboratory, pending funding.
Contact: [email protected] and [email protected]