We used this on a pilot project on 50 hectares of potato's along with fish based compost and worm castings .... and at the time I must admit the results were astonishing to say the least .. I have always used charcoal in one form or another in my gardening and the benefits were always plain to see .....
bio char is a bi product of gasification, pyrolysis and 2 a lesser degree plasma technology in which the remains of mbt (mechanical and biological treatment) of land fill waste are cooked under pressure with out oxygen (well all most) .
as incinerator type technology go's its the lesser of evil and is much better than strait forward burning of untreated waste ....I have seen them all working in one way or another in Germany, but am still not convinced about the process but the bio char that is left has very good potential as a soil enhancer and a very good carbon sink long term ................but we shall see
what is bio-char
Biochar is ... plant biomass derived materials contained within the black carbon (BC) continuum. This definition includes chars and charcoal, and excludes fossil fuel products or geogenic carbon.
Biochar is a fine-grained charcoal high in organic carbon and largely resistant to decomposition. It is produced from pyrolysis of plant and waste feedstocks. As a soil amendment, biochar creates a recalcitrant soil carbon pool that is carbon-negative, serving as a net withdrawal of atmospheric carbon dioxide stored in highly recalcitrant soil carbon stocks.
The enhanced nutrient retention capacity of biochar-amended soil not only reduces the total fertilizer requirements but also the climate and environmental impact of crop lands. Char-amended soils have shown 50 - 80 percent reductions in nitrous oxide emissions and reduced run-off of phosphorus into surface waters and leaching of nitrogen into groundwater.
As a soil amendment, biochar significantly increases the efficiency of and reduces the need for traditional chemical fertilizers, while greatly enhancing crop yields. Renewable oils and gases co-produced in the pyrolysis process can be used as fuel or fuel feed stocks. Biochar thus offers promise for its soil productivity and climate benefits.
source and videos
Green guru James Lovelock claims that the only hope of mitigating catastrophic climate change is through biochar - biomass "cooked" by pyrolysis.
It produces gas for energy generation, and charcoal - a stable form of carbon.
The charcoal is then buried in the ground, making the process "carbon negative".
Researchers say biochar can also improve farm productivity and cut demand for carbon-intensive fertilisers.
There's a flurry of worldwide interest in the technology, but is the hype justified?
A ripe whiff of sludge drifts across the sewage works in Bingen, Germany, as a conveyor belt feeds a stream of semi-dried effluent into a steel container.
Behind the container, the treated effluent emerges in the form of glittering black granules. In a flash of eco-alchemy, they are turning sewage into charcoal.
The charcoal is then buried to lock the carbon into the ground and prevent it entering the atmosphere.
Proponents of the technology say it is so effective at storing carbon that it should be included in the next global climate agreement.
Engineer Helmut Gerber from the University of Applied Sciences, Bingen explains how biochar is created.
Burying the biochar can also improve soil fertility, say experts.
Field trials are about to begin at Rothamsted, south-east England, to assess the benefits to soil structure and water retention.
Experiments in Australia, US and Germany are already showing some remarkable results - especially on otherwise poor soils where the honeycomb granules of biochar act as a reservoir for moisture and fertilisers.
Could biochar be used to make plants grow faster?
A growing worldwide movement is now bringing together the soil scientists fascinated by the benefits of biochar, which was first discovered in Pre-Columbian Amazonia, and the engineers devising new ways of making the char.
They are being backed by activists who are concerned about climate change.
At Bingen, the design engineer for the biochar plant, Helmut Gerber, originally devised the pyrolysis equipment to overcome the problem of ash from sewage waste choking conventional boilers.
Normally, sewage treatment is a significant source of greenhouse gases. The waste is usually incinerated (with more emissions) and the resulting ash is used in the building industry.
At Bingen, 10% of the sewage stream is being diverted to the prototype pyrolysis plant, where it is heated with minimum oxygen.
Carbon monoxide and methane are driven off and burned to heat the pyrolysis process.
Mr Gerber claims his process radically cuts the fuel costs and carbon emissions needed to treat the sewage.
'Carbon negative' process
Working with Professor Winfried Sehn from Bingen's University of Applied Sciences, Mr Gerber calculates that 60% of the carbon from the sewage is locked up in the char.
The buried carbon will be kept from entering the atmosphere for a projected 1,000 years or more.
And as the sewage was originally created from plants, which removed CO2 from the atmosphere, the total process is described as carbon negative.
The pyrolyser at Bingen - like others being developed elsewhere - can transform any carbon-based substance, including some plastics.
That means pyrolysis can get energy from agricultural waste, food waste and biomass. But the catch is that it creates less energy than burning biomass in a conventional way.
Research by oil giant Shell, showing a keen interest in biochar as a carbon storage mechanism, suggests that it can capture half the carbon from the biomass by foregoing a third of the potential energy.
Dr Bruno Glaser
Now there is a lot of excitement about what biochar can achieve
Dr Bruno Glaser
For all its apparent benefits, there are substantial barriers to the progress of biochar.
Perfecting and disseminating the technology at an affordable price will be an issue.
Moreover, current financial systems reward energy production from biomass and waste - not carbon storage. Biochar would need clear global incentives.
One key to its progress will be ongoing research into the soil benefits.
The porous biochar attracts worms. It also captures nutrients that would otherwise run off the land, which reduces the need for carbon-intensive fertilisers.
Research at Cornell University in New York, US, suggests that burying biochar appears to double the capacity of soils to store organic carbon (compost releases its carbon in a few years).
Research in Australia suggests that biochar also reduces emissions of the powerful greenhouse gas nitrous oxide from soil.
New studies at the University of Bayreuth, Germany, shows that biochar may almost double plant growth in poor soils.
"Research on biochar began back in 1947," says Dr Bruno Glaser, a researcher from the University of Bayreuth.
"But this has been forgotten until the 1980s. Now there is a lot of excitement about what biochar can achieve."
Dr Glaser is working on studies to see how effective it proves to be on poor soils in northern Germany.
At Newcastle University, Professor David Manning is also an enthusiast. He says with the right incentives biochar could perhaps lock up as much carbon as the amount generated by aviation.
Several biochar stoves have been developed for use in developing countries. Belize and a number of African governments are attempting to get biochar accepted as a climate change mitigation and adaptation technology for the post-2012 treaty to be negotiated in Copenhagen in December.
This post has been edited by ripthedrift: 29 June 2009 - 11:39 AM