From UPSC perspective, the following things are important :
Prelims level : Biochar and its application
Mains level : Use as organic farming option
A new research has shown that Biochar application is more effective in promoting pulses growth and yield in Ghana.
Try this PYQ:
Q.In the context of which one of the following are the terms ‘pyrolysis and plasma gasification’ mentioned? (CSP 2019)
(a) Extraction of rare earth elements
(b) Natural gas extraction technologies
(c) Hydrogen fuel-based automobiles
(d) Waste-to-energy technologies
What is Biochar?
- Biochar is a high-carbon, fine-grained residue that is currently produced through modern pyrolysis processes (direct thermal decomposition of biomass in the absence of oxygen and preventing combustion).
- It produces a mixture of solids (the biochar proper), liquid (bio-oil), and gas (syngas) products.
- Biochar may increase soil fertility of acidic soils (low pH soils), increase agricultural productivity, and provide protection against some foliar and soil-borne diseases.
- Carbon Sink: The burning and natural decomposition of biomass releases large amounts of carbon dioxide and methane to the Earth’s atmosphere. The biochar production process also releases CO2 (up to 50% of the biomass); however the remaining carbon content is stable indefinitely.
- Soil Amendment: Biochar is recognized as offering a number of soil health benefits. The extremely porous nature of biochar is found to be effective at retaining both water and water-soluble nutrients. Its presence in the earth can improve water quality, increase soil fertility, raise agricultural productivity, and reduce pressure on old-growth forests.
- Water retention: Biochar is hygroscopic. Thus it is a desirable soil material in many locations due to its ability to attract and retain water.
What is Pyrolysis?
- Pyrolysis is the thermal decomposition of materials at elevated temperatures in an inert atmosphere.
- It involves a change in chemical composition. The word is coined from the Greek-derived elements pyro “fire” and lysis “separating”.
- It is most commonly used in the treatment of organic materials. It is one of the processes involved in charring wood.
- It is considered as the first step in the processes of gasification or combustion.
How does it work?
- In general, pyrolysis of organic substances produces volatile products and leaves a solid residue enriched in carbon, char.
- Extreme pyrolysis, which leaves mostly carbon as the residue, is called carbonization.
- The process is used heavily in the chemical industry, for example, to produce ethylene, many forms of carbon, and other chemicals from petroleum, coal, and even wood, to produce coke from coal.