https://www.huffingtonpost.ca/jason-tetro/biofuel-microbes-food-waste_a_23416592/
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04/27/2018 10:08 EDT | Updated 04/27/2018 11:29 EDT
A Microbial Breakthrough Could Make This Mess The Future Of Fuel
Thanks to advancements in biofuel, we finally may find a way to keep our
hunger for oil-based energy alive while ensuring we keep the environment
safe.
Jason Tetro
Microbiology, Health & Hygiene Expert
For most Canadians, oil-based products are thought to come only from
fossils. Drilling, mining, fracking and other extraction procedures
appear to be the only way to ensure a sustainable supply of gasoline,
lubricants, natural gas and plastics. However, environmental concerns
have pitted our dependence on oil against the sustainability of the planet.
Finding new ways to produce oil for manufacturing and processing has
been in the spotlight for a few decades. One of the most interesting
paths involves the use of food to produce petrochemicals such as
biofuels. This process has become widespread across the globe and has
become integrated in the energy policies of several countries, including
Canada. Even so, the level of use of these more environmentally friendly
products pales to traditional fossil sources.
The idea of using biological material as fuel may seem new, but it dates
back over a century to the dawn of automobiles. Rudolf Diesel made cars
to run on peanut oil. In turn, Henry Ford developed his Model T to run
on hemp-based fuels. Unfortunately, the costs were far higher than
fossil-based options and, eventually, the industry stuck with the
cheaper option.
Biofuels didn't go away, but were relegated to the fringes of the fuel
industry until the 1970s when two major issues arose. One involved the
health of individuals exposed to lead from gasoline. The other happened
when shortages and spikes in prices occurred due to restrictions in
fossil-fuel supply. The public backlash led governments to return to the
concept of using biological material to help ease the pain.
Back then, the easiest answer was corn, which could be used to produce
ethanol through microbial fermentation. Yet, this meant taking what
could be considered a valuable food away from farmers and the public.
This led to a completely different worry involving food security. For
biofuels to be sustainable, they needed to come from non-competitive
biological sources. By the middle of the last decade, the answer was
found in the form of food waste.
Over a quarter of all food energy is lost by throwing out what we don't
want or need to keep humans and animals properly fed. This represents a
massive potential for the formation of sustainable biofuels. Research
has suggested converting all food waste into energy could result in
about 1,200 exajoules of energy. Currently, the global need for
fossil-based fuels is about 600 exajoules according to the International
Energy Agency. If energy could be produced by only half of the food
waste we create, we could eliminate the need for fossil-based fuels.
Of course, making food waste into a useful energy product is a
significant challenge. Turning something such as a banana peel, or
discarded meat product, or a used napkin into oil is a difficult and
expensive process. The first step involves breaking down the compounds
into individual molecules such that they can then be built up into the
fuel chemicals we need. This can be done chemically; however, it is
difficult and very hard to upscale without major costs.
But thanks to a group of Irish researchers, we may be well on our way to
accomplishing this goal. They have figured out a way to turn wasted food
into an energy source capable of becoming fuel. The trick to their
achievement lies not in chemistry but in microbes.
Bacteria and fungi are known to be excellent at decomposing organic
matter into the basic building blocks for energy. But certain species
have the uncanny ability to make a variety of molecules known as
precursors. As the name implies, these chemicals can be treated to form
the oil-based products we desire. One of the most useful types of
precursors is known as caproate. From this molecule, a variety of
oil-based products can be manufactured.
The team hoped to make caproate using only microbes and a few
easy-to-acquire chemicals such as hydrogen gas and acetate, better known
as vinegar. The process was designed to act in the same way as another
large-scale form of microbial production, fermentation. But unlike beer
and wine, where the end product is alcohol, the team wanted to end up
with the precursor.
The process was fairly simple. The team collected food waste from a
local restaurant and then separated the organic material such as peels
and meat from non-useable items such as bones, shells and plastics.
Mixtures were made and added to a fermentation reactor along with a
variety of different species of bacteria. The vessel was then closed off
and oxygen was removed, making the entire system anaerobic. After
different time points over the course of two weeks, the vessel was
opened and the group determined the amount caproate made.
The protocol needed some tweaking, but eventually the team achieved
success. They were able to produce a large supply of caproate in as
little as a few days. The amount was high enough to make this procedure
useful for further studies in the future. They had successfully turned
food waste into the basic necessity for oil production.
While the team acknowledges this is only the beginning of a new
direction in the production of fossil-fuel alternatives, the results
demonstrate the potential for using waste to produce energy. In light of
all the concerns regarding fossil-based products in Canada and around
the world, this study suggests we may be able to forget about the
debates sooner than later. We only need for governments and other
investors to ensure these newer technologies are able to survive and
thrive. If this can be achieved, we finally may find a way to keep our
hunger for oil-based energy alive while ensuring we keep the environment
safe.