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Plowing Carbon Into the Fields
OzPeter writes "A wheat farmer in Australia has eliminated adding fertilizer to his crop by the simple process of injecting the cooled diesel exhaust of his modified tractor into the ground when the wheat is being sown. In doing so he eliminates releasing carbon into the atmosphere and at the same time saves himself up to $500,000 (AUD) that would have been required to fertilize his 3,900 hectares in the traditional way. Yet his crop yields over the last two years have been at least on par with his best yields since 2001. The technique was developed by a Canadian, Gary Lewis of Bio Agtive, and is currently in trial at 100 farms around the world."
Funny this sounded familiar, I submitted the story about the Canadian farmer three years ago. That article says it was developed by a farmer named Darrel Carlisle and is generally more informative.
Or you can read the article and see that CO2 helps anaerobic bacteria that also happen to be nitrogen fixers...guess the journalists know more than you, after all.
ASCII stupid question, get a stupid ANSI
Not that blowing it into the atmosphere is much better, but doesn't diesel exhaust contain all sorts of nasty toxins?
I don't recall the exact exhaust gas composition, but in my younger days working at a research lab we participated in a series of animal studies on diesel exhaust. You could pump a lot of diesel exhaust through lab animals without any serious side effects. Some of the high dose groups had lungs that looked like they had been smoking, but none of them died from toxins in the exhaust. I don't remember there being any statistical correlation to cancers or cell differentiation, either. But that was a long time ago.
My vague memory of the conclusions were that you breath a lot of diesel exhaust without harmful side effects, although the particulates would keep your pulmonary macrophage in business.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
Fertilizer is nitrogen and phosphorus. Exhaust is carbon and oxygen. Can one pair really be replaced by the other?
"The exhaust gases are believed to stimulate microbial activity and root growth, allowing the plants to more efficiently extract nutrient and moisture from the soil."
What keeps the injected CO2 from leaking back out?
"The system relies on attraction between negatively-charged ions in the gases and the soil’s positively charged alkaline component to hold the gases in the soil, as well as sealing it in."
http://abovecapricorn.blogspot.com/2009/10/soil-carbon-may-come-from-tractor.html
There was a critique of the chapter in Super Freakonomics on realclimate.org:
http://www.realclimate.org/index.php/archives/2009/10/why-levitt-and-dubner-like-geo-engineering-and-why-they-are-wrong/
http://www.realclimate.org/index.php/archives/2009/10/an-open-letter-to-steve-levitt/
I think it's worth reading.
Anyway, I don't believe any geo-engineering solution will help combat GW, for a simple reason: conservation of energy. Fossil fuels are so important because we can use energy at faster rate than we could obtain it from the sun (their EROI is higher), because it has been accumulating for millions years. So any solution to CO2 reduction different from plain reduction of fossil fuel usage will have to ultimately convert excess CO2 somehow, and this will cost same amount of energy (or more) as it would just use a renewable resource (which there is ultimately only one, the Sun) for energy. Basically, the problem is that the rate at which we consume energy is not sustainable; we will have to match our rate to that of what we can get from the Sun.
I found the article by "The Economist". The article debunks the claim that increasing wealth results in a decreasing population. The implications for excessive population growth are alarming.
You didn't find an article that backs your assertion. There are at least two effects to note. First, high HDI countries (which boils down to high GDP per capita countries) tend to have high immigration by more fertile populations from low HDI countries. Second, that hypothetical increased fertility rate is spread over a longer period (ie, people having children later) which results in lower population growth.
That so-called study is a fine example of lying with statistics - see debunking here http://www.stubbornmule.net/2009/09/baby-bounce/
Not sure what diesel engines you've been dealing with, but I've never seen one without a throttle.
A diesel engine receives fuel based on RPM and, you hope, load. The pedal in the car controls the maximum position of a governor which controls maximum fuel delivery. As the engine approaches this speed (as output meets load) the fuel delivery decreases until a given RPM is reached. Or in the words of a pedant, a diesel has an accelerator pedal, but no throttle. In a carbureted vehicle the throttle controls both air and fuel delivery directly. In fuel-injected gasoline vehicles, the pedal usually controls an intake restrictor butterfly valve, and a throttle position sensor which instructs the computer (in unison with the oxygen sensor.) Diesels should have as much intake air as possible.
Even without a throttle they don't burn perfectly, ever.
True.
If done properly it simply results in less than the maximum amount entering the combustion chamber. With fuel injection engines it should not result in an improper ration of air to fuel, just less of both.
In both fuel injected and carbureted engines you err on the side of richness, and during closed loop operation (e.g. cruising, idle, deceleration, or mild acceleration) the mixture continually bounces to either side of rich and lean. The catalytic converter smooths out the rich and lean spots before they become emissions, because it swings back and forth several times a second.
You think all that black you see pooring out of the engine under high load is CO? No.
No, that's partly those PAHs and partly unburned hydrocarbons, one of the primary bad guys when it comes to emissions. The NOx output of diesels is only significant in the aggregate; it's higher than that of typical gasoline-powered vehicles. Biodiesel has more NOx, but less CO. Nitric oxides are a major component of acid rain.
in smaller quantities its not a problem, the body deals with carbon monoxide in our atmosphere by simply replacing the cells that have been rendered useless by carbon monoxide.
but I was using those.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Look at all these carcinogens
All in extremely low quantities and most of which are filtered out/ broken down by modern DPF and/or SCR.
Diesel is not the dirty thing of yesteryear. Reports of hazardous exhaust is greatly exaggerated and outdated. Basically the only thing that comes out of the tailpipe is CO2 and H2O.
And yes I am a diesel emissions engineer.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".