How To Turn Waste Into Useful Fuel and other products: Plasma Arc Waste Disposal

Introduction

Plasma arc waste disposal is a fairly new technology that can process Municipal Solid Waste (MSW), petroleum coke, coal, and biomass into synthetic gas which can be used to generate electricity, for heating, as well as a feedstock for synthetic fuels such as ethanol. It will also create various forms of inert solid material that can be used to make concrete, recyclable metals, and insulation. Syngas is made up of Hydrogen gas and Carbon Monoxide gas, which could be used as a vehicle fuel in the future with fuel cells or combustion engines.

How does it work?


source

What are its advantages?

1. It reduces the need for landfills.
Sometimes called "artificial lightning," plasma can have temperatures that can exceed 7,000 degrees centigrade -- that's three times hotter than fossil fuels and hotter than the surface of the sun.

The plasma arc would instantly convert organic materials into synthetic gas, often called "syngas," and melt inorganic materials, which when cooled, become rock-like and can be sold as construction materials. With no remaining waste to deal with, landfills become obsolete.

2. Existing landfills could be mined for energy.
In many regions of the United States, it would be more cost-effective to take municipal solid waste to a plasma gasification plant for energy production than to dump it in a landfill. When plasma gasification is fully developed, even existing landfills could be economically mined for energy production, environmental cleanup and land reuse.

3. It's energy efficient.
Plasma gasification of 1 ton of average municipal solid wastes would send about 815 Kilowatt-hours of electricity to the grid. This is 20 to 50 percent more electricity to the grid than any other emerging thermal waste-to-energy technology. In addition, this amount of power is over six times the electricity required to conduct the plasma gasification process.

4. It's working in other countries.
Since 2002, two commercial waste-to-energy plasma gasification plants have been operating successfully in Japan. The Mihama-Mikata facility processes 24 tons of municipal sold waste and 4 tons of sewage sludge per day, producing steam and hot water for local use. The Utashinai plant processes up to 300 tons per day of waste and/or automobile shredder residue. This facility produces up to 7.9 Megawatts of electricity, of which 3.6 MW are used to run the plasma torches and the plant, and up to 4.3 MW are sent to the electrical power grid. In Ottawa, Canada, people are evaluating a demonstration facility that is currently processing 94 tons of waste per day, sending 4 MW of power to the grid.

5. It could produce ethanol fuel.
If all the municipal solid waste in the United States was processed by plasma gasification, over 5 percent of the U.S. electrical energy requirements could be produced. This amount of power is equal to the amount of hydropower produced in the United States, or equal to about 25 nuclear power plants. Similarly, the 2007 U.S. Energy Act recommends that "garbage" be used to replace edible foods such as corn to produce ethanol. It was estimated that waste could produce up to 30 percent of the 36 billion gallons of ethanol required by the year 2022.

6. It could produce the most renewable energy.
Plasma processing of municipal solid waste in the United States has the potential to create more renewable energy than the projected energy from solar, wind, landfill gas and geothermal energies combined.

7. It's clean burning.
Because of the high temperatures, the low volume of gas emissions and the dissociation of organic compounds, gaseous emissions from plasma waste processes are much cleaner than from other kinds of gasification or incineration processes.

8. It reduces greenhouse gas emissions.
In landfills, garbage produces methane, a greenhouse gas. But if that garbage were sent to a plasma gasification facility, it would not have a chance to produce methane. What's more, the energy generated could replace energy made at a coal-fired plant. In fact, for every ton of municipal solid waste sent to a plasma gasification facility for power production, 2 tons of CO2 emissions could be reduced from the atmosphere.

9. It gasifies more than garbage.
At least 15 companies in the United States and Canada are actively developing plasma gasification projects. In addition to municipal solid waste, the plants will process industrial waste, biomass, coal, coke and other carbonaceous materials. The plants will produce electricity as well as ethanol, methanol, diesel fuel, hydrogen and other syngas-based fuel products. Construction on some of these facilities is expected to begin in 2009.

10. It has a future.
Plasma gasification could play even more important roles in the fields of clean coal gasification, secondary oil recovery, and oil shale and tar sands recovery processes. Truly. Plasma gasification is an incipient environmental blockbuster, ready to leap ahead of current concepts of waste disposal, energy production and environmental cleanup.

Dr. Louis J. Circeo is a principal research scientist and director of plasma research at the Georgia Tech Research Institute. He has been involved with plasma technology research since 1971, and holds five U.S. patents relating to plasma technology applications.

www.thesciencecouncil.com...

• Plasma processing of MSW has the potential to supply ~5% of U.S. electricity needs - Equivalent to ~25 nuclear power plants
  
• Can create more renewable energy than the projected energy from solar, wind, landfill gas and geothermal energies combined
  
• When fully developed, it may become cost-effective to mine existing landfills for energy production
  

www.thesciencecouncil.com...

What can the slag be used for?

Roads, concrete, asphalt, recyclable metals, insulation, sound proofing, and agriculture.

What do the critics say

The intense heat from plasma arc will not destroy heavy metals. Heavy metals, such as lead,
cadmium, mercury and chromium, will be vaporized. It is very difficult and expensive to trap heavy
metals once they are in vapor form. There is no known air pollution device that can monitor toxic
metal emissions on a continuous basis. So, heavy metals invariably will be released through the
smokestacks endangering the public s health and the environment.

The life-span of the left over slag is uncertain since there have been no studies on how long the slag
will keep its structure. Without testing for harmful leaching of heavy metals and other toxics in the
slag, knowledge about the public health impact of plasma are technology is incomplete and
inadequate.

www.essentialaction.org...

Thanks.

reply to post by C0bzz


Interesting! I wonder what the energy returned on energy invested is for something that involves making plasma though? Either way converting garbage into fuel sounds pretty good to me.

**edit because upon closer reading I see the EROEI is 6 - not too shabby at all!

I have been harping about this technology for years. It is a fantastic way to recycle materials and produces a net energy gain. In addition you get raw materials and the Bio-Gas. Thanks for bringing this back to ATS member's attention.

The idea is great but very similar to a old Fischer–Tropsch process just up dated to use a plasma torch to heat the waste.

The one problem i have with the output is that they want to make ethanol for fuel.
ethanol is a very inefficient bio fuel. low BTUs cars get 20% less mpg with ethanol over gasoline. plus the cars have to be modified to run on pure ethanol.

This same process would make butanol that has the same BTU as gasoline.
cars can run on pure butanol without modifications and get the same mpg as gasoline.
I know if a couple people that buy butanol to run there cars on during smog test and they can get most cars to pass, These cars will fail on gasoline.
Butanol has a high flashpoint of 35 °C, which is a benefit for fire safety,
Butanol can also be used for fuel cells.
www.butanol.com...
auto-racing.speedtv.com...
nabc.cals.cornell.edu...

Using ether this process or the Fischer–Tropsch process all trash, toxic organic chemical waste. sewage and AG waste should be turned into fuel.

The congress should be passing laws to eliminate/ban landfills.
This would force cities to find a use for the materials put on landfills like making fuel from it.

One way would be to tax by cubic foot all organic waste that is buried.
Then when the cities find they can make money making fuel from organic waste instead of paying a tax to bury it these plants will take off.

This would eliminate landfills for organic waste in the US. It also would eliminate drug metabolites from our rivers that are caused by sewage treatment plants.

No more toxic seepage into ground water.

Ethanol is a cheap additive or fuel that gets less MPG allowing more fuel to be sold.
The fuel companies just love this as they make more money.

A city like LA Calif could turn all there trash into fuel.
A small amount of this fuel would be used for there public transportation system and all city fleet vehicles and the rest sold for profit.
Because this synthetic fuel is much cleaner then petroleum fuel they would have less maintenance cost on the public transportation fleet and city fleet.
The taxpayers would pay less as the surplus would be sold for a profit offsetting cost.
If trucks going to and from the port of LA used this fuel they would run cleaner and the air would be cleaner.

After about 10 years the system would pay for its self and the taxpayers would have a win win situation.
less smog because this synthetic fuel burns cleaner.

If the cost of oil went up like it did in 2007-8 to $120 a barrel the city would not have to pass on the cost because they would no longer be using petroleum fuel and the taxpayer would really win.

This is a great process that ticks a lot of boxes as far as energy is concerned but its downfall IMHO is that it accelerates the return of the carbon content in waste to the atmosphere which will make it unattractive from a climate change point of view and subject to whatever penalties are applied to CO2 producers. Let's imagine this process is adopted on a very large scale globally and consider the consequences of releasing the carbon in the world's landfill waste back into the atmosphere in the form of CO2 over a period of years or decades as opposed to centuries or millenia. There's a double whammy here too because the process of 'burning' carbon monoxide is extracting an extra oxygen atom from the air for every CO molecule 'burned'.

Originally posted by Pilgrum
This is a great process that ticks a lot of boxes as far as energy is concerned but its downfall IMHO is that it accelerates the return of the carbon content in waste to the atmosphere which will make it unattractive from a climate change point of view and subject to whatever penalties are applied to CO2 producers. Let's imagine this process is adopted on a very large scale globally and consider the consequences of releasing the carbon in the world's landfill waste back into the atmosphere in the form of CO2 over a period of years or decades as opposed to centuries or millenia. There's a double whammy here too because the process of 'burning' carbon monoxide is extracting an extra oxygen atom from the air for every CO molecule 'burned'.

If you put trash in a landfill you get methane a lot more potent green house gas.

if you make Butanol instead of gasoline
Butanol reduced hydrocarbons by 95%,
Butanol reduced carbon monoxide to 0.01%
Butanol reduced oxides of nitrogen by 37%
Butanol increased auto mileage by 9%

butanol C4H9OH
gasoline C8H18

As you can see gasoline has 8 carbon over 4 for butanol.
This means that gasoline puts twice as much carbon into the atmosphere.

gasoline also has toluene and benzene in it.
benzene C6H6
toluene C6H5CH3

Along with having more carbon both are cancer causing chemicals.
Butanol can be used in Direct Alcohol Fuel Cells (DAFC's) so this would make it a low cost conversion fuel both types of cars could use the same fuel from the same pump as the country changed over.

Butanol can be blended in any percentage with gasoline seamlessly as we increase production till we reach 100% butanol
No need to build a completely new fuel supply infrastructure like you would have to with hydrogen fuel cell systems.
news.mongabay.com...

www.thesciencecouncil.com...

I should still stop methane from going into the atmosphere, which should mean that overall it reduces emissions.


I am unsure of how well this compares to recycling, although I presume we could use this for waste that can not be recycled.

One of the problems with conventional incineration is emissions of Benzene, and Dioxines. I did a search on this technology and found this:

13.2.2 Performance

The results show that:
The technology can process media contaminated with both organic scheduled compounds and inorganic (heavy metal) compounds which are incorporated into a non-leachable material during treatment.
The destruction and removal efficiency (DRE) of organic compounds is greater than 99.99%.
Volatile metals and products of incomplete combustion (PIC) can be generated and may need to be removed by an appropriate scrubber. If required, disposal of the scrubbing water would add additional cost.

The process has been demonstrated successfully under the USEPA SITE program, with the treatment of a mixture of 28000 mg/kg zinc oxide and 1000 mg/kg HCB in diesel oil. destruction and removal efficiency (DRE) exceeded 99.996% (HCB was not detected in the stack gas) and the treated material met TCLP requirements. Particulate emissions in the test did not comply with the regulatory standard and the off-gas treatment system was to be modified accordingly. Particulate emissions from a PACT system in Muttenz were well within the US regulations. Dioxins were not detected in the stack gas (USEPA, 1992).

www.environment.gov.au...

Which means it should are significantly better in that regard.


Thanks.

The temperatures are high enough that you would burn up Dioxines.

With a bag house dust collector and good soda scrubbers you will remove ash and the heavy metals and the scrubbers will remove any acids.

If the plants release any CO2 flue gas it could be removed with MEA (monoethanolamine)

This MEA scrubber system has been used to capture CO2 at the Argus chemical plant in Trona Calif for many years.
They use the CO2 from a large coal fired co-gen power plant to process soda ash(sodium carbonate) into bicarbonate of soda.
I use to run this MEA plant as a operations technician.