Recycling Fuels

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Recycling Fuels

The push for carbon-neutral fuels and the minimizing of waste has lead to the discovery of some new and emerging forms of recycling for fuels. The new and emerging technologies include carbon capture, the use of trash for heat and fuel, using plastic as fuel, recycling waste fuel, and turning waste food into fuel. A very new and currently being tested source of fuel is CO2 emissions recycling. Each form of recycling is addressed below.

SWEDEN RECYCLING TRASH FOR HEAT & FUEL

Sweden banned organic and combustible waste in landfills during the years 2002 to 2005. In 1975 the average recycled waste per person was around 40 pounds. In 2016 that number rose to 357 pounds being recycled. During that same time period, an average person produced 430 pounds of trash sent to a landfill, and now only 6.6 pounds are produced. This is very important because organic waste in landfills generates methane which is 72 times more potent as a greenhouse gas than carbon dioxide.

These efforts have reduced landfill usage and the burning of fossil fuels. To handle the amount of organic and combustible trash produced, Sweden has shifted to burning the trash. This switch has lead to the avoidance of emitting 467,000 tons of carbon dioxide in just one year.

The trash-burning operations produce heat, electricity, and methane biogas. The biogas is utilized as a fuel for 200+ city buses, along with garbage trucks, taxes, and private vehicles. A special biogas digester is utilized to create methane that is refined, scrubbed of carbon dioxide, and finally distributed to fuel stations.

Critics are claiming that this type of power plant discourages recycling and waste reduction and detracts investments from renewable energy programs. However, Sweden has increased its recycling efforts along with its wind and solar energy capacities, aiming to have 100 percent renewable energy by 2040. They also have the goal of net zero greenhouse gas emissions by the year 2045.

FOOD WASTE TO ENERGY

Similar to Sweden’s initiatives of burning organic waste, companies around the world are building factories to convert food waste. While the idea of using food for a fuel source such as biofuel or ethanol is decades old, the ability to turn food waste into biogas differs in the process and is still an emerging technology. Food waste is considered an untapped resource and a high potential for generating energy.

The idea is to prevent landfill waste and utilize food waste. It is estimated that one-third of all food produced around the world is discarded uneaten. Seventy percent of the world’s food waste still goes to landfills. There are currently 800 industrial-scale waste to energy plants located in more than 36 countries around the world. One such plant claims to convert 180,000 tons of food waste a year into biogas that can fuel power plants, vehicles, and other types of equipment. Organic waste from slaughterhouses, breweries, farms, and coffee shops have the potential to power hundreds of homes each day. (Source 9)

CARBON CAPTURE

Efforts are underway to remove carbon dioxide from the atmosphere and then convert it into carbon-neutral fuels. Doing so will stabilize the climate and negate the need to alter energy systems or force people to change their habits.

A Canadian company called Carbon Engineering has already put this technology into place. Carbon Engineering has raised a total of $82.4 million in funding over four rounds from July 2018 with the last round of funding in March 2019. Bill Gates and BHP Billiton Petroleum are the most recent investors in the company and two of the seven total investors.

The technology works by condensing the air in cooling towers with fans. The carbon dioxide is drawn into an alkaline liquid and then separated, frozen, and reheated into a slurry combined with hydrogen to make liquid fuels such as gasoline and jet fuel. Currently, the commercial application of this technology is to create new fuels. Storing the carbon is also possible, but there is no market for this application at the current time.

Carbon Engineering has commercialized two clean energy solutions to produce a net-zero carbon result. These two technologies are Direct Air Capture and Air to Fuels. Direct Air Capture removes carbon dioxide directly from the atmosphere and delivers large-scale negative emissions. With this system, Carbon Engineering can capture one million tons of CO₂ each year which equates to the annual emissions of 250,000 cars. Air to Fuels reduces the carbon footprint in the transportation industry by creating clean synthetic fuels produced from air, water, and renewable power. The fuels produced burn cleaner than fossil fuels and can be produced with 100 times less land than biofuels require.

PLASTIC WASTE INTO FUEL

European countries have strict management strategies, but even so, only 31% of plastic waste is recycled. This has lead to the examination of whether or not different types of plastics can be recycled into fuel. Chemical recycling of plastic can be done by gasification and pyrolysis which yields both energy carriers and feedstocks for fuels.

A synthesis gas can be produced by heating waste plastic with air or steam. This process known as gasification produces products such as diesel and petrol and can also be burned directly to generate electricity. Pyrolysis involves heating waste plastic in the absence of oxygen which yields a mixture of oil that is similar to crude oil. This product can be refined into other transportation fuels. Both processes have lower emissions of sulfur and nitrogen oxides than incineration and provide more flexible ways of storing energy than burning allows.

Gasification of plastic waste requires significant funding and systems which reduces its availability. On the other hand, pyrolysis is modular, requiring little funding in comparison and is easy to roll out. Plants for pyrolysis have already been constructed in Japan, the UK, and the United States. (Source 5)

WASTE FUEL RECYCLING

Waste fuel recycling management programs arise from the International Convention to prevent sea pollution, known as MARPOL 73/78. This international convention applies to 97% of active ships requiring that they properly manage their waste and do not dump it into the sea.

The conventional method of recycling waste fuel is to collect it and burn it off in industrial furnaces. Centrifuges are employed by some processes and consume much power while producing a wet product. Fuels are not recoverable from this method of recycling.

The company Sequoia employs specially designed heat exchanger and recovery systems to treat waste fuel oils. Their method completely evaporates emulsified and free water and recovers diesel from waste fuel oil. Their technology produces a high-value diesel product that meets residual fuel specifications for flash point and water content.

Sertego, another company pioneering the way in waste fuel recycling, developed an innovate set of techniques to treat and recover fuel while minimizing the impact on the environment. They can convert MARPOL waste fuel into motor oil which can be introduced back into the market.

CO2 EMISSIONS RECYCLING

The ability to recycle CO2 emissions is an exciting emerging technology. Researchers from the University of Toronto feel that capturing CO2 can turn it from waste into a valuable energy resource. The idea revolves around the ability to capture the CO2 emitted from power stations and other sources and reduce it into simple hydrocarbon fuels or other small molecules that can then be used as the building blocks for more complex fuels.

Currently, scientists feel that the process is not efficient nor economically feasible. Companies such as Opus-12, Mitsui Chemicals, Carbon Recycling International, Dioxide Materials, and Carbon Electrocatalytic Recycling Toronto are all working to commercially viable solutions.

In addition to the CO2 emission capturing technology, scientists are also experimenting with bio-hybrid approaches and genetically modified bacteria to convert CO2 into more complex chemicals. With the speed of research and advancements in understanding, it is felt that industrial impact could be made within the next five to ten years.
Sources
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Quotes
  • "Methane generated from organic waste in landfills is reduced. This is important. In the short term, methane is about 72 times more potent as a greenhouse gas than carbon dioxide."
  • "Along with reducing landfill, proponents say using trash as an energy supply also reduces burning fossil fuels extracted from the earth and shipped around the world using even more fossil fuels."
  • "“Waste-to-energy is a reasonable short-term solution,” said Owen Gaffney, director of international media and strategy at the Stockholm Resilience Center, which conducts environmental research. “It is less carbon intensive than coal and it uses resources more efficiently than simply putting them in landfill where they would decompose and release greenhouse gases anyway.”"
Quotes
  • "The company has developed technology at its plant in British Columbia that can both remove carbon dioxide from the atmosphere and convert it into carbon-neutral fuels, suggesting such technology could be a meaningful part of the fight against climate change."
  • "This opens up the possibility that we could stabilize the climate for affordable amounts of money without changing the entire energy system or changing everyone's behavior."
  • "The technology works by sucking air into cooling tower-like structures with fans. The acidic carbon dioxide is attracted to an alkaline liquid within the towers that is then taken into the factory where acid and base are separated. The carbon-dioxide containing liquid is frozen and then reheated into a slurry that is combined with hydrogen to make liquid fuels like gasoline and jet fuel."
Quotes
  • "Most rigid plastic products can only be recycled a few times before they lose their original properties and become non-recyclable. Even in European countries with strict waste management strategies, only 31% of plastic waste is recycled."
  • "There are two types of recycling: mechanical and chemical. Mechanical recycling involves sorting, cleaning and shredding plastic to make pellets, which can then be fashioned into other products. This approach works very well if plastic wastes are sorted according to their chemical composition."
  • "Australia has invested a serious amount of funding into research, particularly in waste conversion. It has a solid industrialised infrastructure and a highly skilled workforce."
Quotes
  • "Sequoia’s customers can produce a high-value diesel product, a residual fuel meeting specifications for flash point and water content."
  • "The cost of recycling waste fuel oil into distilled water, diesel fuel and heavy fuel products is about 1.5-3.0 US cents per gallon (approximately US$ 4-8 per m³)."
Quotes
  • "MARPOL waste management arises from the International Convention to prevent sea pollution, MARPOL 73/78, which is an international convention applied to, at least, 97% of active ships, requiring that their waste be properly managed and to avoid dumping waste into the sea."
  • "Sertego works with all types of MARPOL waste included in the international convention, however our activity is mainly focused on MARPOL annex I: bilge waste (basic port service) and tank sludge."
  • "At Sertego, we work on the treatment and recovery of MARPOL waste from Annex I: hydrocarbon waste present in engine room bilges or from fuel purification machines and motor oil."
Quotes
  • "The facility promises to convert 180,000 tons of food waste a year to biogas to fuel a power plant, vehicles and other equipment."
Quotes
  • "Some one third of all food produced around the world gets discarded uneaten, and environmentalists, energy analysts and entrepreneurs are beginning to take notice. Diverting even just a portion of this waste to so-called waste-to-energy (WTE) systems could free up large amounts of landfill space while powering our vehicles and heating our homes, and thus putting a significant dent in our collective carbon footprint."
  • "Currently there are some 800 industrial-scale WTE plants in more than three dozen countries around the world, and likely thousands of smaller systems at individual sites."
  • "The waste from small slaughterhouses, breweries, dairy farms and coffee shops can power hundreds of typical homes each day if the infrastructure is in place to sort, collect and process the flow of organic material."
Quotes
  • "A new paper in the journal Joule argues that technology that uses electricity and water to reduce CO2 into simple hydrocarbon fuels or small molecules that can act as feedstock for more valuable chemicals could be economically viable in the next five to ten years."
  • "Similar to how a plant takes carbon dioxide, sunlight, and water to make sugars for itself, we are interested in using technology to take energy from the sun or other renewable sources to convert CO2 into small building block molecules which can then be upgraded using traditional means of chemistry for commercial use."
  • "There are also a number of potentially disruptive technologies yet to make it out of the lab that could turbo–charge the approach, the researchers added. There has been considerable progress on photocatalytic approaches that use direct sunlight rather than electricity to power the conversion process. That would remove the need for any kind of electricity infrastructure, making the approach far more flexible and portable."
Quotes
  • "[It’s] kind of like a reverse fuel cell. There’s a cathode and an anode; at the anode, water is split into protons and oxygen gas, and at the cathode, CO2 is electrochemically reduced to other value-added chemicals, such as carbon monoxide, methane, ethylene. So you are feeding CO2 protons and electrons [from the water and the electricity], and you are electrochemically reducing them."