Tag Archives: technology

Biofuels: From You to Toilets to Cars

Have you ever wondered where your human wastes travel to when you flush the toilet? Probably not, I mean why would anyone think about that after doing their “business” in the washroom?  It is common knowledge that what we flush down the toilet end up in the sewers, but where do they go after? Sewage wastes are treated to separate wastewater and sludge. The wastewater can then be further treated to be reused, but what can we do with the remaining sewage sludge? The U.S. Department of Energy’s Pacific Northwest National Laboratory has researched a method to convert sewage wastes to biofuel.

Sewage sludge wastes being transported, courtesy of Wikimedia Commons

Sewage sludge wastes being transported, courtesy of Wikimedia Commons

Biofuels are fuels extracted from biomass, a renewable energy source composed of organic materials. There are many methods to convert biomass to biofuels. The following video provides some background on biofuels and commonly used methods to make them:

Autombile exhaust wastes from fossil fuels, courtesy of Wikimedia Commons

Autombile exhaust wastes from fossil fuels, courtesy of Wikimedia Commons

Biofuels can be a suitable substitute for conventional fossil fuels, coal and gas, when supplying energy to devices and vehicles. The development of biofuels is important for the purpose of reducing the use of fossil fuels. Since fossil fuels produces many wastes when burned. These wastes include air pollution, which is harmful to human health, and greenhouse gases such as carbon dioxide, which contribute to global warming. The use of biofuels can reduce the production of theses harmful wastes.

So how do we convert our human wastes to biofuel. The Department of Energy found that using hydrothermal liquefaction can break down human wastes to simpler chemical compounds. Hydrothermal liquefaction (HTL) is the process of breaking down wet biomass to crude-like oil under high pressure and temperature. In this case the wastes are pressurized to 3,000 pounds per square inch and 300 degrees Celsius. This process gives biocrude and a liquid phase. These parts can be treated to create fuel. Any other solid by-products from the creation of fuel are used for fertilizer, due to high nutrient content.

Personally, I think processing biofuel via sewage wastes is an ingenious method to kill two birds with one stone. Firstly, we produce high quality fuel that can replace fossil fuels. This will lower the production of greenhouse gases and pollution, thus improving the environment. Secondly, it will be very cost-efficient for the government, as any other sewage processing, transport and disposal are no longer necessary. Lastly, this process produces no unusable by-products, as the fuel and remaining organic matter can be used for many purposes.

– Nelson Yu

References:

Fuel from sewage is the future – and it’s closer than you think. http://www.pnnl.gov/news/release.aspx?id=4317 (accessed November 5, 2016).

What are Biofuels?. http://www.conserve-energy-future.com/advantages-and-disadvantages-of-biofuels.php (accessed November 5, 2016).

Hydrothermal liquefaction — the most promising path to a sustainable bio-oil production. https://www.eurekalert.org/pub_releases/2013-02/au-hl020613.php (accessed November 5, 2016).

Graphene Batteries: A Better Alternative

There’s been a lot of fuss recently regarding the new phones. The Samsung Note 7 and the iPhone 7, particularly, seem to exhibit a major flaw: They tend to explode. Well, exploding may be overstating the actual situation, as most of the time they just catch on fire, but it is still quite a major inconvenience.

So why is this happening? Its not like lithium-ion batteries are a new technology, right?

Well, it is true that companies have been using these batteries for a long time now, but the problem has to do with how companies have began to stretch out the limits of the design in order to satisfy its customers.

The lithium-ion batteries work like this:

lithium-ion-battery-powering-device

Simplified diagram of a Lithium-ion battery. (Image courtesy of Sustainable-nano.)

Where the solution inside the battery helps move the electric charge in and out of the battery.

This these batteries, there are certain limits such as size and charge that dictate the safety and stability of the battery. Therefore, when the companies begin to push the limits of the battery design so that they can give a longer charge, and use less space. What this creates is a very unstable battery, and a very unhappy customer.

So what can we do to fix this?

Meet the Graphene battery.

Graphene is a material that has many wonderful properties. It’s lightweight, conducts electricity extremely well, and is incredibly stable, forming a sturdy yet flexible material. The best part is: it is found in everyday items such as pencils and charcoal, so it won’t be a limited resource either.

Graphene batteries work by using layers of graphene to act as the plates that move electricity in and out of the battery. By using graphene instead of lithium or other metal plates, we fix two major problems:

  1. Graphene holds a much larger amount of charge, and is able to charge up in just a fraction of the time. Pictured below is the G-King graphene battery. At the size of a regular smartphone, it holds more than 3 times the charge of a regular phone battery. Best of all, it can be fully charged in fifteen minutes.

    dongxu-g-king-battery-1000x665

    The G-King, in all its glory. (Image courtesy of Graphene-info.)

  2. Since graphene is so safe and flexible, it opens up new venues of battery design. Graphene batteries are made in all sorts of shapes and sizes, enabling batteries in all sorts of convenient places.

    vorbeck-vor-power-img_assist-400x216

    A bag strap with an attached graphene battery inside as a easy to use recharging station. (Image courtesy of Graphene-info.)

Although most graphene products are still under development, expect to see some great results coming through the next couple of years. I, for one, will be sure to pick these up as soon as they hit the general market. In the meantime, you can watch this video about the unveiling of the G-King battery.

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-Dennis Lin, Undergrad Chemistry