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Plasma Plants Vaporize Trash While Creating Energy
Jason Sahler writes "Recently St. Lucie County in Florida announced that it has teamed up with Geoplasma to develop the United States' first plasma gasification plant. The plant will use super-hot 10,000 degree Fahrenheit plasma to effectively vaporize 1,500 tons of trash each day, which in turn spins turbines to generate 60MW of electricity — enough to power 50,000 homes!"
Most of what we produce, most 'trash' is going to be hydrogen, carbon, and oxygen. So I have to wonder, is this 'burning' it, or is it going to be producing diatomic hydrogen and oxygen? Does anyone have any experience with plasma gasification that could explain why this wouldn't produce unwanted byproducts from the gaseous components cooling down?
10,000 degrees fahrenheit is around 5,600 degrees celcius, which is approximately the surface temperature of the sun.
If ever the whatcouldpossiblygowrong tag were appropriate...
How much energy is used in generating that 10,000 degree plasma, hmm? Less than what it'll output by incinerating trash? I'd like to see that.
It's apparently self sustaining.
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FINALLY! The Mr. Fusion is only a few years away!
No longer will I need Plutonium to generate the 3.3 Jigawatts nessecary to power my Flux Capacitor.
From working with a garbage to energy plant in Virginia, they had the ability to generate much more then the 80MW (from memory) they were generating. They had to impose the limit or they would qualify as a utility under the state guidelines, and be subject to regulation. Since the plant was privately owned, and wanted run themselves, they had to let a lot of the power go as heat.
They would regulate it some by the rate at which the garbage went in, but when it starts backing up, you have no choice but to burn it.
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Their web site just screams "vaporware". In fact, the useful-scale project has been cancelled, and only a small "demonstration plant" will be built.
The real questions about this are 1) do they really get out more energy than they put in, and 2) how much processing of the exhaust gases is required? Westinghoue Plasma Corporation (which, sadly, has little to do with Westinghouse) claims that 1000 tonnes (metric?) of solid waste produces the energy equivalent of 1 (one) barrel of oil. So this isn't a big energy producer. Ordinary waste-to-energy plants do better than that, but don't burn as clean as a plasma arc.
The other problem is what comes out. Organic compounds are literally blasted apart into atoms at those temperatures, so it deals with biowaste just fine. CO2 comes out, of course. NOx, maybe. Everything heavier (metals, etc.) is supposed to come out as a "molten slag" suitable for cement aggregate. Not sure what the cement industry thinks of this. They're usually quite picky about what's allowed in cement aggregate. Some contaminants interfere with the chemistry of concrete curing and make bad concrete. It might be good for filling in swamps and such.
This process will NOT "create" energy. In fact, I doubt it will have any more efficiency than the current conventional methods of turning trash into useful components. Keep in mind that vaporization of any solids from room temperature it going to take a massive amount of energy. Spinning turbines with the gasses until it condenses is an obvious step to take, but there is a lot of legislation that can be made to supplant the need for more technology. Just take a look at Germany. You can get a hefty fine for putting a can in the bio-degradable receptacle, but those guys have one helluva disposal system.
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Still asleep here, so my visualizing of this was:
"Plasma " ok that's the hot stuff
" plants " O, the beautiful trees, the nature... hmm, wait a second. Plasma trees? plasma grass?! What the...
" Vaporize trash " Dear freaking gawd! trash vaposizing red hot trees?!? Scorching grassy plains to vaporise trash on?
" While creating energy " They are self sustaining?! It's the end of the world! We're all gonna diiie!
Self-sustaining != Self-starting
It is self sustaining in the way your car's electrical system is: It provides enough juice to start the engine, which recharges your battery and runs your radio/lights/cigarette lighter.
Am I the only person who upon reading the title had the sudden mental image of flora with glowing plasma leaves that devour trash like venus fly-traps devour flies? Whew, I need to lay off the midnight sushi...
The standard conversion is actually closer to 1MW per 1000 homes (1kW per home) on average. When you're running the drier or the electric stove, sure it's a lot more. But if you're just watching TV with a few lights on it is probably closer to a 400W load. The big problem happens around 4:45PM. Businesses are still open, but people have gone home and turned all the lights on. So the load usually peaks around that time. Obviously the grid has more capacity than 1kW per home, but on average this is about the average usage. What does your monthly bill say? If it is around 650-800 kW-hr then you only use about 1kW on average. (I have worked for a large utility and now work for a turbine manufacturer)
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
I think you're seeing this from the wrong angle. The trash is "fuel" for the turbine. Think along the lines of coal burning power plants. The coal isn't free, it's a resource that is used to create electricity. I don't see how burning trash would be that different?
The article is offline right now.. so i'm really just guessing here. But the purpose of the plant isn't just another powerplant, it's a trash removal plant as well.
http://soylentnews.org/~tibman
I do a LOT of work on refuse disposal options, principally for the UK food industry. From the top of my head:- Use of plasma for waste disposal, this is not new, there was a french system proposed a few years ago for disposal of medical waste, looks like pathogens get a bit uncomfortable at tempertaures of several thousands of C. (this is from a New Scientist article, unable to refernce at the moment) The article references syngas, this is usually derived from anaerobic heating (>600oC) of organic matter and was used to make town gas from coal for street lighting. This can be used on food wastes (there is a huge amount in the UK) and run through the Fischer Troupe process to make petrol etc. The downsides :-
High pressure - increases capital costs geometrically with scale.
Chemical plant - NIMBYS do not like them (what a suprise. )
Process does not like water - food waste is 60% water.
Energy intensive (work out how much energy is needed to volitise teh 5 Million tonnes of food waste generated in the UK each year - its a lot).
The upsides :-
Established and proven technology.
Lots of very cheap raw material.
Use the energy content of the raw material to dry and vaporise the residue (an approx. 30% energy cost penalty - but the source is cheap)
Will consume anything organic, so mixed and contaminated food waste not a problem - will accomodate glass and metal contaminants
Best of all, as the plant scales down, there is an exponential decrease in the wall thickness needed for pipework etc. needed, so cost decreases at the same rate. You could have a pallet sized unit getting through a tonne per hour (Perdue University have done this for cleaning up waste at militry bases) for a very worthwhile cost. Note in the UK, landfill costs are now in the region of £60/tonne and rising by £8/year due to land fill tax. God help you if you have to render high risk material prior to landfill, your are then looking at a cost of about £100/tonne. A £25M t/o food plant will easily generate 2000 tonnes of food waste per year. This is significant, given most food manufacturers are operating on net margins in the very low single figures. A back of the metaphorical fag packet calculation showed that we could generate enough petrol from such sources in the UK to meet our commitment to add 5% from renewables to our petrol every year.
If you want more vegetables, there are plenty of scientific ways to make that happen on any quality of land, not necessarily requiring soil. You can grow tomatoes in hydroponic greenhouses in the desert like this company does, for example.
The reality is that we don't have enough planet for everyone to be a meat-eater, at least not in the American sense. For every 100 pounds of grain protein you give to cattle as feed, you only get back 10 pounds of protein as meat. So although American cattle typically spend their lives in a feedlot rather than on arable land, the fact still remains that that land must be used to grow grain to feed the cattle. We could support roughly 10 times more people with the same amount of arable land if everyone was vegetarian.
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