Showing posts with label pyrolysis. Show all posts
Showing posts with label pyrolysis. Show all posts

Friday, January 11, 2013

President Obama, here's a climate plan!


President Obama, now is the time to act on climate change! Climate change won't wait. There are encouraging signs indicating that a summit is being organized, to be hosted at the White House, to launch a comprehensive climate action plan with broad-based and bipartisan support.

What plan? Well, here's a climate plan!



The first line of action of most climate plans is to cut emissions. Two types of feebates, working separately, yet complimentary, can cut emissions most effectively and can be implemented locally in a budget-neutral way, without requiring complicated international agreements:
  1. energy feebates (pictured above) in sectors such as electricity, heating and transport, and 
  2. feebates in sectors such as agriculture, land use, waste management and construction (pictured below).
Pictured on the left are feebates that impose fees on sales of Portland cement, nitrogen fertilizers and livestock products. This will make further cuts in emissions.

The revenues are then used to fund rebates on clean construction and on soil supplements containing biochar and olive sand, which will remove carbon dioxide from the atmosphere and store it in buildings, soil, river banks, roads and pavement.

Working seperately, yet complimentary, energy feebates and feebates in agriculture and other sectors can dramatically bring down carbon dioxide levels in the atmosphere and oceans; as a result, atmospheric carbon dioxide could be brought back to pre-industral levels of around 280ppm by the end of the century.

For further discussion, also see Towards a Sustainable Economy
Thus, these two feebates will be effective on two lines of action, i.e. on cutting emissions and on reducing carbon dioxide levels in the atmosphere and oceans.

Even with these measures, temperatures will keep rising for some time, as excess ocean heat will get transferred to the atmosphere over the years and as aerosols (particularly sulfur) fall away that are currently emitted when fuel is burned and thus mask the full wrath of global warming.

Continued warming comes with numerous feedbacks. Combined, these feedbacks threaten to trigger runaway global warming, i.e. warming that will cause mass death, destruction and extinction.

How to avoid mass-scale death, destruction and extinction
This means that, in addition to the first two lines of action, further lines of action will be necessary, i.e. Solar radiation management, and Methane management and further action. Further action includes regulatory measures such as ending commercial flights over the Arctic and support for pyrolysis to avoid burning of biomass. The image below pictures several methods of Arctic methane management that should get high priority, given the threat of hydrate destabilization in the Arctic.
Arctic Methane Management

Fees imposed on commercial flights could fund solar radiation management, while the feebates described above will also be most effective in further lines of action, i.e. in Arctic methane management and further action.

Wednesday, January 2, 2013

Turning forest waste into biochar

Too much biomass waste in tundra and boreal forests makes them prone to wildfires, especially when heatwaves strike. Furthermore, leaving biomass waste in the forest can cause a lot of methane emisions from decomposition.

In order to reduce such methane emissions and the risk of wildfires, it makes sense to reduce excess biomass waste in fields and forests. Until now, this was typically done by controlled burning of biomass, which also causes emissions, but far less than wildfires do. Avoiding wildfires is particularly important for the Arctic, which is vulnerable to soot deposits originating from wildfires in tundra and boreal forest. Such soot deposits cause more sunlight to be absorbed, accelerating the decline of snow and ice in the Arctic.


A team of scientists at University of Washington, sponsored by the National Science Foundation, has developed a way to remove woody biomass waste from forests without burning it in the traditional way. The team has developed a portable kiln that can be assembled around a heap of waste wood and convert it to biochar on the spot, while the biochar can also be burried in the soil on the spot.

Demonstration in Kerby, Oregon,
Nov. 6, 2012, 
 by Carbon Cultures
Credit:
Marcus Kauffman at Flickr
The team initially started testing the effectiveness of a heat-resistant blanket thrown over woody debris.  The team then developed portable panels that are assembled in a kiln around a slash pile.

Students have set up a company, Carbon Cultures, to promote the technology and to sell biochar. CEO of Carbon Cultures is Jenny Knoth, also a Ph.D. candidate in environmental and forest sciences.

The kiln restricts the amount of oxygen that can reach the biomass, which is transformed by pyrolysis into biochar. The woody waste is heated up to temperatures of about 1,100 degrees Fahrenheit (600 Celsius), as the kiln transforms some 800 pounds of wood into 200 pounds of biochar in less than two hours. “We also extinguish with water because it helps keep oxygen out and also activates the charcoal [making it more fertile in soil].”

Currently, the total costs of disposing of forest slash heaps (the collections of wood waste) approximate a billion dollars a year in the United States, according to Knoth.

And of course, adding biochar to the soil is a great way to reduce carbon dioxide levels in the atmosphere. “Biochar is proven to fix carbon for hundreds of thousands of years,” Knoth said.
Demonstration in Kerby, Oregon, November 6, 2012, organized by Carbon Cultures Credit: Marcus Kauffman at Flickr

As said, when biomass waste is left in the open air, methane emissions are produced during its decomposition. Moreover, such waste will fuel wildfires, which produce huge amounts of emissions. The traditional response therefore is to burn such waste. Pyrolyzing biomass produces even less greenhouse gases and less soot, compared to such controlled burning.

Biochar is produced in the process, which can be added to the soil on the spot. This will help soil retain moisture, nutrients and soil microbes, making forests more healthy, preventing erosion and thus reduces the risk of wildfires even further, in addition to the reduction already achieved by removal of surplus waste.

A healthy forest will retain more moist in its soil, in the air under its canopy, and in the air above the forest through expiration, resulting in more clouds that act as sunshades to keep the forest cool and return the moist to the forest through rainfall. Forests reinforce patterns of air pressure and humidity that result in long-distance air currents that bring moist air from the sea inland to be deposited onto the forest in the form of rain. Finally, clouds can reflect more sunlight back into space, thus reducing the chance of heatwaves.

References

Recycling wood waste - The Daily of the University of Washington
Helping Landowners with Waste Wood While Improving Agribusiness and Energy - National Science Foundation

Related

- Biochar
- CU-Boulder gets into biochar