BIOCHAR: PREPARATION AND IT'S ROLE IN CLIMATE CHANGE MITIGATION

1. Presented by: PUJA SINHA
ID No.- 18230AGC031
Bsc.(Hons.),Agriculture
3rd year, 5th semester
Submitted to: Dr. ARDITH SANKAR
Assistant Professor
Dept. of Agronomy
IAS,B.H.U(R.G.S.C)
AGR-311: Practical Crop Production – I (Kharif Crops)
Topic – BIOCHAR : PREPARATION AND IT’S ROLE IN AGRICULTURE AND CLIMATE
CHANGE MITIGATION

2. CONTENTSC
CONTENTS
Origin of biochar
What is biochar?
Why biochar should be used?
Characteristics of biochar
Sources of feedstocks and process of biochar production
Methods of biochar production
Soil application of biochar
Effects of biochar incorporation in soil
Biochar for climate change mitigation
Critical factors for maximising the benefits of biochar
Implications of biochar use
Prospects
Conclusion

3. FROM WHERE DOES THE IDEA OF BIOCHAR COME?
Left – a nutrient-poor oxisol;
Right – an oxisol transformed into
fertile terra preta using biochar.
 origin dates back to the pre-
Columbian era, when the ancient
Amerindian communities in the
Brazilian Amazon region first made
dark earth soils (Terra Preta de Índio
[black earth of the Indian]), also
known as terra preta, through slash-
and-char.
 considered as the most fertile soil in
the world
 Have high carbon content,
up to 150 g C/kg soil, compared to the
surrounding soils (20–30 g C/kg soil)

4. WHAT IS BIOCHAR?
 Biochar is a fine-grained, carbon-rich, porous product remaining after plant
biomass has been subjected to thermo-chemical conversion process
(pyrolysis) at low temperatures (~350–600°C) in an environment with little or
no oxygen. (Amonette and Joseph, 2009).
 Pyrolysis typically, gives three products: liquid (bio-oil); solid (biochar); and gas
(syngas)
 Yield of each product depends on the pyrolysis process (slow, fast, and flash)
and conditions (ie, feedstock, temperature, pressure, time, heating, and rate)
 Biochar is not a pure carbon, but rather mix of carbon (C approx 70%),
hydrogen (H), oxygen (O), nitrogen (N), sulphur (S) and ash in different
proporties.
(Masek, 2009).

5.  Major constituents of biochar
MOISTURE:
-Can hold large amount of
moisture
ASH:
-Include metals and non
metals
-Depends on feedstock.
-Provide nutrients to plants
and increase soil pH
STABLE CARBON:
-Persistence is indicated by
ratio of Hydrogen to Organic
Carbon
-Makes biochar useful as
long-term climate change
mitigation strategy
UNSTABLE CARBON:
-Relatively rapidly
decomposed
-can influence crop nutrition

6. Agricultural profitability
Management of pollution and
eutrophication risk to
environment
Restoration of degraded land
Sequestration of carbon from
the atmosphere
Residue management
WHY BIOCHAR SHOULD BE USED?

7. CHARACTERISTICS OF
BIOCHAR

8.  PHYSICAL CHARACTERISTICS
 Bulk density:
• Biochars: 0.06 – 0.7 g/cm3 (depends on feedstock sources and temperature)
• Eg:BD of rice and wheat straw biochar was lower than that of maize stover and
pearl millet stalk biochar.
 Particle density:
• Grass biochars: 0.25-0.3 g/cm3
• Wood biochars: 0.47 to 0.6 g/cm3
• affects the ease of mobility and loss of biochar in wind and water.
 Particle size:
• depends on feedstock and its pre-processing, production technique (screw
augers, rotating drums etc.) and temperature.
 Micro and macro porosity:
• Pores can be classified as macro-, meso- and micro-pores, with different
relevance to physiochemical phenomena for biochar interactions with the
environment.
• Micropores are responsible for the high sorption capacity of most biochars.
They have also been shown to provide microhabitats for microorganisms.

9.  Surface area:
• 120 sq.m/gm(400℃ and below) ; 460 sq.m/gm(600-900℃)
• Woody biochars: medium to high surface area.
• Ash biochars: low surface area
 Hydrophobicity:
• caused by tars (aliphatic compounds) condensing on the biochar surface
during pyrolysis.
• affects the water uptake by biochar, and therefore water holding capacity of
biochar, and microbial interactions.
• Low temperature biochars are strongly hydrophobic, but longer pyrolysis time
or washing biochar can reduce hydrophobicity.
• As biochar reacts in soil, hydrophobicity may decrease.
 Grindability:
• The Hardgrove grindability index (HGI) of raw wood, torrefied wood and
charcoal (woody biochar) as a function of the volatile matter content.
• low HGI --- poor grindability
• high HGI --- easily grindable.

10.  CHEMICAL CHARACTERISTICS
 pH and liming value:
• pH value: 8.2-13 (increases with ash content and pyrolysis temperature)
• Eg: pH of most woody biochars is around 6 at 350°C, increases to about 8 at
450°C, and continues to increases with temperatures above 450°.
• The liming value of biochars determines their capacity to lower soil acidity
expressed as calcium carbonate (CaCO3) equivalent.
 Cation exchange capacity(CEC):
• Low temperature biochars usually have higher CEC, but high temperature
biochars can adsorb more nutrients and OM.
• Directly proportional to production temperature
 Electrical conductivity(EC):
• Softwood biochars - 19-4mS/m;Hardwood biochars – upto 3 times.
• Corn stalks are around 200mS/m, poultry manure up to 500mS/m.
• Biochar added to soil can increase soil EC
 Total carbon content and C/N ratio:
• vary from 33.0 to 82.4%.
• algae-based biochars have low C/N ratios and that wood (hard and soft)
feedstock biochars have the highest C/N ratios.

11.  Macronutrient content:
• N and S compound tends to volatize at a temperature above 200 and
375°C, respectively, whereas, K and P volatilize between 700 and 800°C
• High-temperature biochars (800°C) have a higher extractable NO3-,
while low-temperature biochars (350°C) have greater amounts of
extractable P, NH4 +, and phenols

12. ELECTROCHEMICAL
CHARACTERISTICS
 Most biochars are semiconductors and can store
electrons and give out electrons.
 High temperature biochars (>600℃) are conductors
of electricity.
 Some carbon in the biochar can react with oxygen
to produce CO2, H2O and electrons. These
electrons can be accepted by oxygen, Fe3+, nitrates
or some bacteria.
 Thus biochar can assist in making nutrients more
available.

13. SOURCES OF FEEDSTOCKS AND PROCESS OF
BIOCHAR PRODUCTION :
FIG: Potential and concurrent sources of biochar production

14. SOME COMMON METHODS OF PREPARATION OF BIOCHAR
1) HEAP METHOD
a) Traditional earth kiln b) Holy mother biochar kiln

15. 2) DRUM METHOD:
Biochar preparation at IARI: Drum used for preparation of biochar (A); Drum filled with maize
stover (B); Drum covered with lid (C); Drum placed inside the firebrick kiln heating provide
at the base of drum externally (D); Biochar removed from drum (F); and
Biochar the final product with little percentage of ash (F)
A B C
D E F

16. 3) BIOCHAR STOVE:

17. BIOCHAR SOILAPPLICATION:
-Broadcasted
mechanically by
spreader or hand
-can be incorporated
through hand hoe,
drought animals or
by mechanical
ploughing and
discing
-Deep-banded
application in rows
-biochar is placed into
the rhizosphere
-applied in bands of
about 50mm to
100mm wide, with a
spacing of
approximately 200mm
to 600 mm and at a
suitable depth
-Incorporation with
composts and
manures
-The compost or
manure mixed with
biochar can be
applied by uniform
topsoil mixing or can
also be top-dressed
between rows of
trees and vines
without incorporation
-FIG.(left) Trenching
method to
incorporate biochar
and correct wilting of
a pine tree; (right)
addition of biochar to
holes around mature
orchard trees
a. METHODS OF APPLICATION

18.  Application rate of biochar:
• 5-50 tonnes/hectare(in general)
 Frequency of application:
• single application is sufficient for several growing season.

19. EFFECTs OF BIOCHAR INCORPORATION IN AGRICULTURAL SOIL:
 Improved soil fertility and crop yields
 Increased fertiliser use efficiency(10-30%)
 Improved water retention(upto 18%), aeration and soil tilth
 Higher CEC(upto 50%) and less nutrient runoff
 Decreased methane(100%) and nitrous oxide(50%) emission from soil
 Increases soil organic carbon
 Can use wide variety of feedstocks including crop residues such as wheat and
corn straw, poultry litter, cow manure, forest debris, and other farm based
biomass resources
 Reduce the acidity of soil by acting as liming agent
 Reduced aluminium toxicity
 Supports soil microbial life
TABLE:The impact of biochar on the three most common and most problematic soils:
Acrisols, Lithosols (Lixisols) and Nitosols.

20. EFFECTS OF BIOCHAR ON PLANT GROWTH AND YIELD:

21. BIOCHAR FOR CLIMATE
CHANGE MITIGATION

22. A) CARBON SEQUESTRATION:
 removal of atmospheric CO2 through photosynthesis to form organic matter, which is ultimately
stored in the soil as stable forms of C. The maximum sustainable technical potential for carbon
abatement from biochar is 1-1.8 giga ton (Gt) C per year by 2050.
 biochar leads to sequestration of about 50% of the initial carbon compared to the low amounts
retained after burning (3%) and biological decomposition (less than 10-20% after 5-10 years)
CARBON CYCLE BIOCHAR CYCLE

23. B) MITIGATION OF GREENHOUSE GAS EMISSIONS:
FIG: Potential mechanisms of soil greenhouse gas (GHG) fluxes in response to biochar amendment.
The red line and blue line represent the positive and negative regulations, respectively.
 Soil is a significant source of nitrous oxide (N2O) and both a source and sink of
methane (CH4). These gases are 23 and 298 times more potent than carbon
dioxide (CO2) as greenhouse gases in the atmosphere.

24. IMPLICATIONS OF BIOCHAR USE:
 Economic implications
 Environmental implications
 Potential health issues
 Dry biochar is liable to wind erosion
 Response of local communities to adopt
 Unavailability of farm labour, higher wage rates for collection and
processing of crop residue
 Lack of appropriate farm machines for on-farm recycling of crop
residue and inadequate policy support/ incentives for crop residue
recycling
CRITICAL FACTORS FOR MAXIMISING BENEFITS FROM BIOCHAR:
 Quality of feedstock biomass
 Optimum temperature for biomass production
 Soil carbon level
 Soil types and soil moisture
 Soil pH and soil contamination

25. PROSPECTS:
 As a soil additive for soil remediation
 Soil substrates – Highly adsorbing and effective for in cleaning wastewater; in
particular urban wastewater contaminated by heavy metals.
 A barrier preventing pesticides getting into surface water – berms around fields
 Treating pond and lake water – bio-char is good for adsorbing pesticides and
fertilizers, as well as for improving water aeration.
 In Japan and China bamboo-based bio-chars are being woven into textiles to
gain better thermal and breathing properties and to reduce the development of
odours through sweat. The same aim is pursued through the inclusion of bio-
char in shoe soles and socks
 It is potentially applicable as the reactive medium for groundwater remediation
 It serves as a good platform for doping and immobilizing nanomaterials
 the petrochemical sector – as it is obliged to secure sustainable C-based
feedstocks in the face of dwindling fossil fuel reserves
 the agricultural residues and by-products sector – as land scarcity stimulates
the need to optimize the sustainable values of these materials

26. CONCLUSION
 Store recalcitrant form of carbon in soil
 Crop residue management
 Reduce GHGs emission
 Carbon sequestration by photosynthesis
 Improve soil physical and chemical properties
 Overcome wastelands by reclaimation of soil
 Improve soil fertility and crop yields
 Increase fertliser use efficiency
 Can produce electricty, bio-oils, and/or hydrogen fuels
 Lack of awareness and inadequate policy support
 Potential health issues like pneumoconiosis and silicosis
 Involves large biomass demand for production
 Need to investigate and utilise it to reduce our emissions and sustain
soils, but we cannot rely on it for solving our emerging problems

27. REFRENCES:
 Use of Biochar for Soil Health Enhancement and Greenhouse Gas Mitigation in
India:Potential and Constraints - Ch. Srinivasarao, K.A. Gopinath, G. Venkatesh, A.K.
Dubey, Harsha Wakudkar,T.J. Purakayastha, H. Pathak, Pramod Jha, B.L. Lakaria, D.J.
Rajkhowa, Sandip Mandal, S. Jeyaraman, B. Venkateswarlu and A.K. Sikka (BIOCHAR
BULLETIN BY CRIDA)
 Biochar Production and its Use in Rainfed Agriculture: Experiences from CRIDA - G
Venkatesh, K A Gopinath, K Sammi Reddy, B Sanjeeva Reddy, J V N S Prasad, G
Rajeshwar Rao, G Pratibha, Ch Srinivasarao, G Ravindra Chary,M Prabhakar, V Visha
Kumari, Arun K Shankar and B Venkateswarlu(CRIDA-NICRA Research Bulletin
02/2018)
 Biochar: Production, Characterization, and Applications, edited by Yong Sik Ok, Sophie M.
Uchimiya, Scott X. Chang, Nanthi Bolan
 Biochar for Environmental Management Science and Technology, Edited by Johannes
Lehmann and Stephen Joseph
 BIOCHAR APPLICATION ESSENTIAL SOIL MICROBIAL ECOLOGY ,Edited by
T. Komang Ralebitso-Senior, Caroline H. Orr

28.  Guidelines on Practical Aspects of Biochar Application to Field Soil in Various Soil
Management Systems - Julie Major , PhD, Extension Director (International
Biochar Initiative)
 https://www.bioenergyconsult.com/applications-of-biochar/
 http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-
548X2020000200327
 https://www.researchgate.net/figure/Comparison-of-normal-and-biochar-carbon-cycles-
Lehmann-2007_fig6_277667665
 https://onlinelibrary.wiley.com/doi/full/10.1111/gcbb.12376
 https://biochar.international/guides/properties-fresh-aged-biochar/
 https://warmheartworldwide.org/putting-biochar-to-use-at-the-edge-quality-soils-and-
measurement/

29. THANKYOU