Plasma Process Turns Garbage into Energy

In the movie “Back to the Future,” Doc Brown, having just returned from the year 2015, poured garbage into a “Mr Fusion” to generate fuel for his sports car/time machine. Here we are in 2015, still waiting for fusion technology to power the world. Here’s the next best thing: “Mr Plasma.”

Okay, so it’s not really called “Mr Plasma”^* and it’s not exactly portable, but it does use plasma to turn garbage into fuel. Advanced Plasma Power (APP) has received funding to build the first plant designed to turn nearly any form of waste into renewable fuels for use in vehicles. The compressed biomethane produced by the plant is equivalent to compressed natural gas, but with a lower carbon footprint. In addition, it doesn’t require hydraulic fracturing (fracking) to obtain it - they just mine the landfills.

The Gasplasma^® Process

The diagram below shows the main steps in the Gasplasma process. After recyclables have been removed, the remaining waste, known as refuse-derived fuel (RDF), is dried and fed into a gasifier. So far, the process is identical to a typical waste-to-energy gasifying operation, with a crude form of syngas being the product. But it’s about to get more interesting...

The low-level syngas and the remaining solids go into the plasma converter, which exposes the material to intense UV light and temperatures around 8000^oC, producing a very clean syngas and a solid product known as Plasmarok^®. The former can be used to create electricity, either as a fuel for a gas turbine or as input to a fuel cell. Syngas can also be converted to a substitute natural gas or a biofuel for vehicles. Plasmarok, the solid byproduct, is an inert, mechanically strong substance that can be used as an aggregate in roads or as a load bearing material in buildings. It’s been independently tested and shown not to leach pollutants into the surrounding environment.

The plasma converter’s intense heat allows it to process virtually any material, including most hazardous waste.

Nature Recycles Everything

In nature, there is no trash; everything is recycled. One organism’s waste is another’s sustenance. That’s why life on our home planet has thrived for several billion years. The Gasplasma process could mine landfills until they’re empty, at which point humanity can start sending its refuse directly to a Gasplasma processing facility, bypassing the landfill altogether. A sustainable future has no room for landfills.

Back to the Future

In the lab where I teach, the bulletin board shows this prediction from a 1949 edition of Popular Mechanics: “Computers in the future may weigh no more than 1.5 tons.” It only took about 20 years for that prophesy to become a reality, so I’ll make a bold prognosis here, and maybe it’ll appear in someone’s lab in 2035:

In the future, plasma-based waste-to-energy plants could weigh less than 1.5 tons.

Remember where you read it first!

APP has a demonstration/R&D plant that’s been operational for several years. The new facility will be the first ever commercial waste-to-energy facility that uses the patented Gasplasma process. Here’s a virtual tour of the plant, which will be constructed in 2016:

If you'd like to read all the gory details, check out  APP’s white paper describing the process.

Images and video courtesy of Advanced Plasma Power

^*Note to the Advanced Plasma Power executives: if you decide to name your product “Mr Plasma,” you may send royalty checks to Tom Lombardo, c/o ENGINEERING.com.