Biochar: Difference between revisions

Latest revision as of 18:11, 16 April 2024

Biochar is a name for charcoal (pyrolized plant matter), especially in usage as soil amendment. It represents a scalable low-tech strategy for carbon sequestration in the soil.

Charcoal has many effects on soil fertility, although it is not much of a nutrient in itself. Some of the world's most productive soils (e.g. Canadian prairies, Russian Chernozem / or "black earth") are very rich in organic carbon. This is now thought to be pyrogenic in origin, likely originating from prairie or forest fires. This carbon is often thousands of years old, demonstrating its stability in soil.

Besides improving agricultural productivity, charcoal in the soil may serve as a long-term carbon sink, trapping elements that would otherwise contribute to greenhouse climate effects. For more extensive background on Biochar, please consult the Wikipedia entry on biochar.

The Biochar Economy[edit | edit source]

Agricultural charcoal production and interment is a key cyclical ingredient in the regeneration of human habitats, with potential economic significance.

List of uses of biochar[edit | edit source]

Inexpensive soil amelioration for degraded land (i.e. biochar as a liming agent)
Need less land = lower startup costs for a Sustainable Village
Increased biomass productivity
Efficient use of biomass waste for energy generation
Reduced need for fertilizer input (e.g. manure)
Combine biochar with vermicompost to make superb fertilizer.
Pyrolysis gas can be used for energy and as a heat source
Bio-oil and tars are also by-products of pyrolysis, can be turned into biodiesel
Add charcoal to compost heap to speed up composting (probably works via enhanced microbial activity)
Biochar for sale as a source of income for an emerging community

Biochar as a method of carbon sequestration[edit | edit source]

The earth absorbs around 18 times the amount of carbon emitted by humans each year.^{[verification needed]}^W However, about the same amount (one figure given is 99.9%) of this carbon is released to the atmosphere through decomposition. This cycle can be closed by a process known as pyrolysis, in which biomass is heated in the absence of oxygen, creating charcoal and locking carbon in the form of biochar.^W

Locking carbon away from the atmosphere and the carbon cycle described is referred to as carbon sequestration. Biochar can potentially lock away carbon carbon for hundreds or even thousands of years. If a real commitment were made, massive reductions in atmospheric carbon could be achieved - locking down carbon emissions and increasing the wealth of our soils. In conjunction with other geoengineering projects, biochar may truly hold the key to saving our earth from climate catastrophe.

Biochar is also an effective and ecologically friendly soil amendment. It may also have applications in energy production^{[verification needed]} and as a dietary supplement for animals.

Its production was practiced by pre-Columbian Amazonian natives ("terra preta"), and natural processes appear to have created a similar affect in other parts of the world, creating rich soils.

Biochar is not a solution on its own, but it appears to be an important element in comprehensive solution. See Measures to stop global warming.

Biochar Technology[edit | edit source]

(for merged content from Biochar Technology page)

Combine with solar thermal heat source to make a solar pyrolysis unit for charcoal production

Biochar Reactors[edit | edit source]

Several small-scale units have been devised for baking charcoal, many with simple common materials. Charcoal making (pyrolisis) dates back thousands of years in human history, traditionally practiced via earthen pits and mounds. Today, steel drums of different sizes are most commonly utilized due to portability, airflow control options, heat resistance, and availability. See articles below for some examples, and a page on Simple Biochar Kilns.

Suitable feedstocks[edit | edit source]

A variety of feedstocks can be used. Since these often constitute agricultural residues in rural communities, a form of waste is turned into an asset. Possible feedstocks include:

agricultural leftovers: straw, rice hulls, corn stalks, chicken/cattle poop
Fast-growing biomass: bamboo, switchgrass, miscanthus,
Wood scrap/salvage: unused or recovered wood byproducts
Other: leaf litter, grasses, macroalgae, bones (high P content),

Terra preta[edit | edit source]

Terra preta is a type of very dark, fertile anthropogenic soil found in the Amazon Basin. It is basically a mixture of charcoal, bone, and manure. It is very stable and remains in the soil for thousands of years.

Criticism[edit | edit source]

Critics are concerned that large scale biochar production may increase deforestation and pollution levels. However, a variety of biomass feedstocks other than wood can be used (see above). Old-growth forest is likely not a good feedstock because of extensive pre-processing that would be required. Small biomass pieces such as pellets or cherry pits make excellent feedstock. Air pollution from biochar production can be greatly reduced and eliminated through proper production system design.

External links[edit | edit source]

Biochar forum at Permies.com
Gardening with Biochar FAQ [1]
BioEnergy Lists: Terra Preta (Biochar) [2]
International Biochar Initiative (IBI) [3]
Biochar Fund [4]
Biochar Industries Community Biochar Project[5]

Academic research[edit | edit source]

Lehmann, J., Gaunt, J., and Rondon, M..Bio-char and adaptation strategies for global change. Mitigation and Adaptation Strategies for Global Change (2006). 11: 403-427. [6]

Other Research:

Cornell University Dept. of Crop and Soil Sciences [7]
Biochar Farms
International Biochar Initiative [8]

Page data
Authors	KVDP, ben brownell
License	CC-BY-SA-3.0
Ported from	http://opensourceecology.org/wiki/Biochar (original)
Language	English (en)
Related	0 subpages, 30 pages link here
Aliases	Terra preta
Impact	1,801 page views
Created	August 3, 2012 by KVDP
Modified	April 16, 2024 by Kathy Nativi
Cite as	KVDP, ben brownell (2012–2024). "Biochar". Appropedia. Retrieved April 24, 2024.
API queries	basic, semantic, html, files, more

@@ Line 1: / Line 1: @@
-'''Biochar''' is a name for charcoal when it is used for particular purposes, especially as a soil amendment.
+{{Topic notice}}
-=== Overview ===
+{{Merge|Biochar Technology}}
-'''''Note: This page was transwikified from [http://openfarmtech.org Open Source Ecology] - please help adapt it to Appropedia.
-'''''
-[[Image:Biochar2.jpg]]
-According to the [http://www.biochar-international.org/aboutbiochar.html International Biochar Initiative]:
+'''Biochar''' is a name for [[charcoal]] (pyrolized plant matter), especially in usage as soil amendment. It represents a scalable low-tech strategy for carbon sequestration in the soil.
-''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 croplands. Char-amended soils have shown 50 - 80 percent reductions in nitrous oxide emissions and reduced runoff 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 feedstocks. Biochar thus offers promise for its soil productivity and climate benefits.''
+[[File:Biochar2.jpg|Biochar|thumb]]
-Some of the world's most productive soils (e.g. Canadian prairies, Russian [http://en.wikipedia.org/wiki/Chernozem Chernozem] / or "black earth") are very rich in organic carbon. This is now thought to be pyrogenic in origin, likely originating from prairie or forest fires. This carbon is often thousands of years old, demonstrating its stability in soil. For more extensive background on Biochar, please consult the [http://en.wikipedia.org/wiki/Biochar Wikipedia entry on biochar].
+Charcoal has many effects on soil fertility, although it is not much of a nutrient in itself. Some of the world's most productive soils (e.g. Canadian prairies, Russian [https://en.wikipedia.org/wiki/Chernozem Chernozem] / or "black earth") are very rich in organic carbon. This is now thought to be pyrogenic in origin, likely originating from prairie or forest fires. This carbon is often thousands of years old, demonstrating its stability in soil.
-=== Production ===
+Besides improving agricultural productivity, charcoal in the soil may serve as a long-term carbon sink, trapping elements that would otherwise contribute to greenhouse climate effects. For more extensive background on Biochar, please consult the [https://en.wikipedia.org/wiki/Biochar Wikipedia entry on biochar].
-The pyrolysis temperature appears to be a critical factor determining char yield vs. energy yield (tradeoff). Flexi-pyrolysis units are being developed that can be set for either char yield or gasification yield. Dry biomass can be pyrolyzed at regular atmospheric pressure. For wet biomass, pyrolysis at higher pressure ("supercritical") may be necessary, requiring a more sophisticated technical set-up.
-When large chunks of wood are used as feedstock, the charcoal may need to be crushed before use (beware: coal dust explosion !). Many agrigultural feedstocks and leaf litter will not need to be pulverized but will readily break into smaller pieces by themselves. For information on small-scale gardening, please consult the [http://biochar.pbwiki.com/ Gardening with Biochar FAQ], an excellent resource.
+=== The Biochar Economy ===
+[[File:2959038953 31a102dc5d.jpg|thumb|Image from Flickr user '''visionshare''' by CC license]]
+Agricultural charcoal production and interment is a key cyclical ingredient in the regeneration of human habitats, with potential economic significance.
+==== List of uses of biochar ====
+* Inexpensive soil amelioration for degraded land (i.e. biochar as a liming agent)
+* Need less land = lower startup costs for a Sustainable Village
+* Increased biomass productivity
+* Efficient use of biomass waste for energy generation
+* Reduced need for fertilizer input (e.g. manure)
+* Combine biochar with vermicompost to make superb fertilizer.
+* Pyrolysis gas can be used for energy and as a heat source
+* Bio-oil and tars are also by-products of pyrolysis, can be turned into biodiesel
+* Add charcoal to compost heap to speed up composting (probably works via enhanced microbial activity)
+* Biochar for sale as a source of income for an emerging community
+=== Biochar as a method of carbon sequestration ===
-===Biochar as a method of carbon sequestration===
+The [[earth]] absorbs around 18 times the amount of [[carbon]] emitted by humans each year.{{Verification needed}}{{W|Carbon cycle}} However, about the same amount (one figure given is 99.9%) of this carbon is released to the atmosphere through decomposition. This cycle can be closed by a process known as pyrolysis, in which biomass is heated in the absence of oxygen, creating charcoal and locking carbon in the form of biochar.{{W|Biochar}}
-The [[earth]] absorbs around 18 times the amount of [[carbon]] emitted by [[humans]] each year.{{fact}}{{w|Carbon cycle}} However, about the same amount (one figure given is 99.9%) of this carbon is released to the atmosphere through [[decomposition]]. This cycle can be closed by a process known as [[pyrolysis]], in which biomass is heated in the absence of oxygen, creating charcoal and locking carbon in the form of biochar.{{w|Biochar}}
 Locking carbon away from the atmosphere and the carbon cycle described is referred to as [[carbon sequestration]]. Biochar can potentially lock away carbon carbon for hundreds or even thousands of years. If a real commitment were made, massive reductions in atmospheric carbon could be achieved - locking down carbon emissions and increasing the wealth of our soils. In conjunction with other geoengineering projects, biochar may truly hold the key to saving our earth from climate catastrophe.
-Biochar is also an effective and ecologically friendly soil amendment. It may also have applications in [[energy production]]{{fact}} and as a dietary supplement for animals.
+Biochar is also an effective and ecologically friendly soil amendment. It may also have applications in energy production{{Verification needed}} and as a dietary supplement for animals.
 Its production was practiced by pre-Columbian Amazonian natives (''"terra preta"''), and natural processes appear to have created a similar affect in other parts of the world, creating rich soils.
@@ Line 28: / Line 42: @@
 Biochar is not a solution on its own, but it appears to be an important element in comprehensive solution. ''See [[Measures to stop global warming]].''
-=== The Biochar Economy ===
+=== Biochar Technology ===
-[[Image:2959038953 31a102dc5d.jpg]]
+(for merged content from [[Biochar Technology]] page)
+* Combine with solar thermal heat source to make a ''solar pyrolysis unit'' for charcoal production
+=== Biochar Reactors ===
+Several small-scale units have been devised for baking charcoal, many with simple common materials. Charcoal making ([[pyrolisis]]) dates back thousands of years in human history, traditionally practiced via earthen pits and mounds. Today, steel drums of different sizes are most commonly utilized due to portability, airflow control options, heat resistance, and availability. See articles below for some examples, and a page on [[Simple Biochar Kilns]].
+==== Suitable feedstocks ====
+A variety of feedstocks can be used. Since these often constitute agricultural residues in [[rural communities]], a form of waste is turned into an asset. Possible feedstocks include:
+* '''agricultural leftovers:''' straw, rice hulls, corn stalks, chicken/cattle poop
+* '''Fast-growing biomass:''' bamboo, switchgrass, miscanthus,
+* '''Wood scrap/salvage:''' unused or recovered wood byproducts
+* '''Other:''' leaf litter, grasses, macroalgae, bones (high P content),
+==== Terra preta ====
+[[Terra preta]] is a type of very dark, fertile anthropogenic soil found in the Amazon Basin. It is basically a mixture of charcoal, bone, and manure. It is very stable and remains in the soil for thousands of years.
-(image from Flickr user '''visionshare''' by CC license)
+== Criticism ==
-=== Charcoal/biochar in the Appropriate Technology context ===
+Critics are concerned that large scale biochar production may increase deforestation and pollution levels. However, a variety of biomass feedstocks other than wood can be used (see above). Old-growth forest is likely not a good feedstock because of extensive pre-processing that would be required. Small biomass pieces such as pellets or cherry pits make excellent feedstock. Air pollution from biochar production can be greatly reduced and eliminated through proper production system design.
-An obvious question to ask is why we need charcoal. The answer is that as an energy source, it's more energy dense, and most importantly, the calorific value is higher (heat per weight). This means that a higher temperature can be achieved.
-This makes has made the fuel more suitable than wood for transport purposes, at least if it is burned as is (ie for fueling a steam engine). If it was to be compared to ie a [[wood gas]] system, the total amount of energy that can be extracted from charcoal (which is also the original source of charcoal) would without question be lower than that of wood. Perhaps confusing at first glance, this can be explained quite simply: energy is needed to transform wood to charcoal (the first burn (or the "[[pyrolysis]]") will waste a lot of energy. Also, a wood gas system is much more efficient overall (steam engines are only 15% efficient, IC engines are 30% efficient).
+== External links ==
-For other tasks as [[blacksmithing]], the firing of material (ie using a [[kiln]], casting, ...) charcoal is the ''only'' natural material that can be used (wood can not be used). Nowadays, blacksmithing is no longer practiced much, and for casting and firing materials, other (non-natural) materials are being used instead (usually as it allows to better control the temperature, use more efficient kiln/forge designs, ...)
+* [https://permies.com/f/190/biochar Biochar forum at Permies.com]
+* Gardening with Biochar FAQ [http://biochar.pbwiki.com/]
+* BioEnergy Lists: Terra Preta (Biochar) [http://terrapreta.bioenergylists.org/]
+* International Biochar Initiative (IBI) [http://www.biochar-international.org/]
+* Biochar Fund [http://biocharfund.org]
+* Biochar Industries Community Biochar Project[http://www.biocharproject.org/]
-[[File:Homemade waterfilter.jpg|thumb|right|350px|Using charcoal as a filter]]
+== Academic research ==
-Other, more useful purposes of charcoal (from a AT-standpoint) are of a different kind. Water for example can be filtered by means of charcoal. In developed countries, activated charcoal is mostly used rather than regular charcoal, but charcoal can also be used (although it is less efficient).
-==== List of further uses====
+* Lehmann, J., Gaunt, J., and Rondon, M..Bio-char and adaptation strategies for global change. Mitigation and Adaptation Strategies for Global Change (2006). 11: 403-427. [https://web.archive.org/web/20170810234604/http://www.biochar.info/52/downloads/MitAdaptStratGlobChange_Lehmann_2006.pdf]
-*Inexpensive soil amelioration for degraded land (i.e. biochar as a liming agent)
-*Need less land = lower startup costs for a Sustainable Village
-*Increased biomass productivity
-*Efficient use of biomass waste for energy generation
-*Reduced need for fertilizer input (e.g. manure)
-*Combine biochar with vermicompost to make superb fertilizer.
-*Pyrolysis gas can be used for energy and as a heat source
-*Bio-oil and tars are also by-products of pyrolysis, can be turned into biodiesel
-*Add charcoal to compost heap to speed up composting (probably works via enhanced microbial activity)
-*Biochar for sale as a source of income for an emerging community
-*Combine with solar thermal heat source to make a ''solar pyrolysis unit'' for charcoal production
-*Charcoal is useful for other purposes, e.g. metal smelting
-*Charcoal as filter: it has very high absorptive capacities and therfore can be used for water purification and filtration, later become biochar; can also be used to filter pyrolysis gas itself, although it may not be suitable as biochar later (depending on feedstock and potentially hazardous polycyclic aromatic hydrocarbons produced during combustion)
-*Lastly, charcoal powder can also neutralize smell when put into a composting toilet. Then it becomes biochar, ultimately.
-=== Suitable feedstocks ===
+Other Research:
-A variety of feedstocks can be used. Since these often constitute agricultural residues in [[rural communities]], a form of waste is turned into an asset. Possible feedstocks include:
-*'''agricultural leftovers:''' straw, rice hulls, corn stalks, chicken/cattle poop
+* Cornell University Dept. of Crop and Soil Sciences [http://www.css.cornell.edu/faculty/lehmann/research/index.html]
-*'''fast-growing biomass:''' bamboo, switchgrass, miscanthus,
+* Biochar Farms
-*'''other:''' leaf litter, grasses, macroalgae, bones (high P content),
+* International Biochar Initiative [http://www.biochar-international.org/research/education]
-=== Criticism ===
+{{Page data
-Critics are concerned that large-scale biochar production may increase deforestation. However, a variety of biomass feedstocks other than wood can be used (see above). Old-growth forest is likely not a good feedstock because of extensive pre-processing that would be required. Small biomass pieces such as pellets or cherry pits make excellent feedstock.
+| ported-from = http://opensourceecology.org/wiki/Biochar
+}}
-== Terra preta ==
+[[Category:Biochar]]
-'''Terra preta''' is a type of very dark, fertile anthropogenic soil found in the Amazon Basin. It is basically a mixture of charcoal, bone, and manure. It is very stable and remains in the soil for thousands of years.
+[[Category:Fertilizers]]
+[[Category:Soil]]