Fossil fuels have been used to power civilization for ages now, but we are quickly running out. Despite their energy density, the fact that they are nonrenewable makes their future look bleak. Darren Dohme explains that the carbon dioxide emissions from fossil fuels is also one reason scientists are now switching to biofuels.
What are Biofuels by Darren Dohme
Biofuels are just another type of fuel, but these are made from plants, and therefore, they are a lot more sustainable than fossil fuels or nuclear energy. According to Darren Dohme, the plants used to make biofuels are called biomass, and include plants such as corn stalks, wood chips or various grasses.
Biofuels are a good solution because not only is biomass renewable, they also do no release carbon dioxide, which is good for the environment.
How Biofuels are Produced by Darren Dohme
To get energy from biomass, there are three main processes involved:
- Direct consumption from burning solid fuel
- Bacterial consumption that creates methane gas
- Converting solid fuels to liquid or gaseous fuel
The first two, Darren Dohme explains, usually generate enough heat to provide power to generators.
For direct consumption, there isn’t much to be done, since the solid biomass can simply be burned and the energy released in the process is used.
Bacterial consumption on the other hand, allows microorganisms to feed on the sugar in the plants, which is then metabolized and used to produce fuel.
The third type, where biomass is turned into liquid or gas, there is a longer process involved. The most basic way to convert solid biomass into liquid or gaseous fuel is to ferment the crops that have high sugar or fat levels and make ethanol. This ethanol can then be mixed directly into gasoline and used to power cars.
Other times, energy can also be released through synthesis and upgrade. This, Darren Dohme explains, involves deconstruction where the biomass is broken down into its simplest components.
This could include pyrolysis where biomass is broken down without oxygen at very high temperatures to make bio-oil and biochar. Hydrothermal liquefaction can also be used to make bio-oil using wet biomass.
Gasification is another process, where the biomass is cooked at a high temperature with oxygen gas or steam to make hydrogen, and then cleaned up to make it usable as a fuel.
Hydrolysis can also be used, though it involves the use of lower temperatures. Biomass is treated chemically or mechanically and plant cell walls are broken down into the chemicals and proteins they are made of. These can then be used as fuel.
Once the biomass has been deconstructed through any of these ways, they can be synthesized and upgraded to be used as specific types of fuel.
The processing of biomass depends on the type of the biomass itself, as well as the end goal – that is, how it will be used. Wood waste is often the best type with the highest level of contained energy.