Clean Energy From Garbage

Clean engergy from garbage, without a catch?

http://www.popsci.com/popsci/science...cbccdrcrd.html

What's tha' catch.

[Bullitt]

That thing is solid.
wow

“That obsidian-like slag contains toxic heavy metals and breaks down when exposed to water,” claims Brad Van Guilder, a scientist at the Ecology Center in Ann Arbor, Michigan, which advocates for clean air and water. “Dump it in a landfill, and it could one day contaminate local groundwater.” Others wonder about the cleanliness of the syngas. “In the cool-down phases, the components in the syngas could re-form into toxins,” warns Monica Wilson, the international coordinator for the Global Alliance for Incinerator Alternatives, in Berkeley, California.

There's your possible catch. funny how he was talking about using the obsidian waste as bathroom tiles earlier.

[glatt]

Pretty cool. It's not completely clean, of course. When the fuels are burned to make electricity, there is some pollution.

They've been talking about this for years. It's time for some cities to implement it.

I posted about another company's similar process a few years ago.

[HungLikeJesus]

Originally Posted by glatt

Pretty cool. It's not completely clean, of course. When the fuels are burned to make electricity, there is some pollution.

They've been talking about this for years. It's time for some cities to implement it.

I posted about another company's similar process a few years ago.

Here's an update on the Changing World Technologies TDP: http://i-r-squared.blogspot.com/2007...s-reality.html

It's a little long. Here's a short excerpt:

The Bloom Comes off the Rose

So, where does the technology stand today? How far off were those $8 or $15/bbl costs estimates? After all they had run the pilot plants. They had "done so much testing in Philadelphia", they "already know the costs." Turns out they didn't:

Reports from 2005 summarized some economic setbacks which the Carthage plant encountered since its planning stages. It was thought that concern over mad cow disease would prevent the use of turkey waste and other animal products as cattle feed, and thus this waste would be free. As it turns out, turkey waste may still be used as feed in the United States, so that the facility must purchase that feed stock at a cost of $30 to $40 per ton, adding $15 to $20 per barrel to the cost of the oil. Final cost, as of January 2005, was $80/barrel ($1.90/gal).

There's a lot more.

If you're still interested, there's a follow-up to that article here: http://i-r-squared.blogspot.com/sear...20Technologies

[glatt]

Cool. So the technology was proven, but it just wasn't as economical as they hoped due to market reasons.

[HungLikeJesus]

It seems that the technology works, it just wasn't as efficient as they projected (I don't know how they did all the pilot tests without finding that), plus the economics were highly optimistic.

Also, the person in charge is a salesman and not an engineer, and keeps using known-bad data.

I work in this field and see this, unfortunately, too often.

[Kitsune]

The system breaks down materials into basic forms, so I have a difficult time believing that the only byproducts are "an obsidian-like glass" and "a mixture of primarily hydrogen and carbon monoxide". Any materials containing toxic elements, like chlorine and heavy metals, are going to break down to, well, chlorine and heavy metals. That has to go somewhere. Dump old computer components into this and you're going to release lots of lead.

You trap the gasses and use them.

[glatt]

Originally Posted by rkzenrage

You trap the gasses and use them.

Sorry. I only read the first page.

They still come out ahead energy-wise when they trap the gases?

[Clodfobble]

Maybe I'm dumb. Explain to me why the plasma doesn't also vaporize the stainless steel chamber it's inside?

Because the chamber is not in contact with the plasma. I have welded with plasma. It is very hot, but you have to be in contact with the arc.

[BigV]

Consumables. Besides compressed air or nitrogen, there can be as few as two consumables needed for plasma arc cutting. These are the tip and the cutting electrode. If either the tip or the electrode become worn or damaged, the quality of the cut will be affected. The consumables will wear with each cut, but factors like moisture in the air supply, cutting excessively thick materials or poor operator technique will increase the deterioration of the consumables. You will want to have consumables available when you need them, so the ability to order and receive them in a timely fashion is important. Best practice is to replace the tip and the electrode together for optimal quality cuts. It is especially convenient if the cutting machine has a storage compartment for these consumables to save on downtime.

Clodfobble, what happens inside the stainless steel chamber is that the electrodes provide the two points that the plasma "touches". In between, it's that glowing superhotness. But it's not touching the containment vessel.

Imagine an incandescent light bulb. Where the filament glows, that's where the plasma is. Where the filament is supported and receives it's electricity supply, those are the electrodes (in a plasma cutter, as in the example quoted above, they're made of carbon). The glass bulb is analogous to the stainless steel chamber. The filament is very very hot, but the glass is safe, since it's not touching the filament.

The plasma is very very very very hot but the stainless steel chamber is "safe" because it's not touching / in the path of the plasma. The electrodes, however, are, and are indeed consumed. I reckon for the Jetson's garbage disposal, there's some regular maintenance schedule for replacing the electrodes inside the stainless steel chamber.

[BigV]

Back to the opening post's question...

I believe there's a catch too. Leave out for now the garbage processing angle. Even leave out the possibility of water soluble toxic waste. The whole "get more than put in" angle does not compute for me.

Why, oh why in the world wouldn't we just build this thing for the net plus in electrical generation? We could feed it water, or dirt or the cheapest, cleanest, nearest fuel, (no chlorine in, no chlorine out.). And then, what? Just watch the electricity pour out? Something's not right there. This was the promise of a fusion reactor. I've read (beginner level) documentation of these, and I can see "how the math works" to get more energy out than you put in. But I have not seen the same support for this technology. I would think that Al Gore would be all over it, neh? So. Your question stands, rkz. What's the catch?

[Kitsune]

Originally Posted by BigV

The whole "get more than put in" angle does not compute for me.

I thought they were essentially burning trash without flame to generate electricity. They have to provide fuel, gasification takes place, and the resulting products are burned to further the process. This isn't free energy.

But why would we need this when we will see free energy later this year, anyway?

Originally Posted by Kitsune

I thought they were essentially burning trash without flame to generate electricity. They have to provide fuel, gasification takes place, and the resulting products are burned to further the process. This isn't free energy.

But why would we need this when we will see free energy later this year, anyway?

This is not only about the energy, but a clean, efficient, way to deal with waste.
My concern is that this would cause some to reduce their recycling efforts if/when put to widespread use.
I do think it is a great idea and should be fully embraced and will have far more uses in the arena of waste than we currently suspect.
If it is nothing more than a self-sustaining waste process that is needed more than most know and would lose sleep if they had an inkling.
To have any power as profit as well as gasses and excess, such as the slag used a tile, etc, would just be wonderful icing.