Bio-Composting and Carbon Capture Techniques
Science & Technology › Biotechnology – Applications · Topic 11.4
Bio-composting is the controlled decomposition of organic waste such as kitchen scraps, crop residue, leaves and dung by microbes into a dark, stable, nutrient rich material called compost, which improves soil. Methods include aerobic windrow and pit composting, vermicomposting with earthworms, and anaerobic digestion that gives biogas and a manure slurry. Carbon capture techniques remove carbon dioxide from the air or from industrial gases and store it or put it to use. They include natural methods such as forests, mangroves, soil carbon and algae, and technological methods such as carbon capture, utilisation and storage, direct air capture and bioenergy with carbon capture. Both help to cut greenhouse gas emissions and manage waste.
5 min read · UPSC Prelims · Science & Technology · Biotechnology – Applications
At a Glance
- Composting types Aerobic, vermi, anaerobic
- Product Compost and biogas
- Carbon capture Natural and technological
- Terms CCUS, BECCS, biochar
- Indian scheme GOBARdhan
- Exam link UPSC Prelims, Science & Technology: Biotechnology – Applications
Where Does It Fit?
This topic follows bioremediation. Both use biology to handle the waste and pollution we create, one on contaminated sites and the other on organic waste and carbon dioxide. Previous topic: Bioremediation and Microbial Remediation. Next topic: Bioprocessing, Bioreactors and Enzyme Manipulation in the Food Industry.
How Does Bio-Composting Work?
| Method | Features |
|---|---|
| Aerobic composting | Microbes with plenty of air heat the pile to about 55 to 65 degrees Celsius, which kills pathogens. Takes weeks to months |
| Windrow and pit methods | Long heaps or pits of waste turned regularly for air, used in cities and farms |
| Vermicomposting | Earthworms such as Eisenia fetida eat organic waste and produce vermicompost rich in nutrients |
| Anaerobic digestion | Microbes without air make biogas, a mix of methane and carbon dioxide, and a digestate that serves as manure |
| Carbon to nitrogen ratio | A mix of dry carbon rich and wet nitrogen rich waste, roughly 25 to 30 parts carbon to one part nitrogen, gives good composting |
| Stages | Mesophilic, thermophilic, cooling and curing phases |
| Product use | Compost improves soil structure, water holding and nutrients, and reduces chemical fertiliser need |
What Are the Main Carbon Capture Techniques?
- Forests and afforestation: trees store carbon in wood and soil
- Blue carbon: mangroves, seagrass and salt marshes store large amounts of carbon in coastal soils
- Soil carbon: no-till farming, cover crops and compost raise soil carbon
- Biochar: heating biomass with little air makes a stable charcoal that locks carbon in soil for long periods
- Carbon capture, utilisation and storage: capturing carbon dioxide at power plants, steel and cement units, then using it or storing it underground
- Direct air capture: machines that remove carbon dioxide from the air, still costly
- Bioenergy with carbon capture and storage: burning biomass for energy and storing the carbon dioxide
- Algae and microbes: algal systems use carbon dioxide for growth and can make fuel or feed
What Else Should You Remember?
- Solid Waste Management Rules: the Rules of 2016 required segregation of waste at source and promoted composting. New rules were notified in 2024 to 2026, so check the current version
- Swachh Bharat Mission Urban 2.0: aims at garbage free cities with processing of all wet waste
- GOBARdhan: Galvanizing Organic Bio-Agro Resources Dhan, launched in 2018, converts cattle dung and farm waste into biogas and compost
- Compressed biogas: the SATAT scheme of 2018 supports plants that make compressed biogas for transport
- Indore model: Indore has been ranked the cleanest city in the Swachh Survekshan many times, with strong segregation and processing
- Fertiliser Control Order: fermented organic manure and city compost have standards under the order, and the Market Development Assistance supports sales
- Methane: landfills release methane, a strong greenhouse gas, so diverting wet waste to compost cuts emissions
- Stubble management: crop residue can be composted with decomposer microbes instead of burnt, as with the Pusa decomposer
- India and CCUS: the NITI Aayog published a report in 2022 on carbon capture, utilisation and storage as a tool for hard to abate sectors
- Net zero: India has set a target of net zero emissions by 2070, and removals will support it
- Limits: capture has high energy and money cost, storage sites must be safe and permanent, and natural sinks can be lost to fire or land change
- Link: fuels from biomass connect to National Policy on Biofuels,…">Biofuels: Bioethanol, Biodiesel and Biogas from Biomass
Why Does It Matter for the Exam?
- Compost types: aerobic, vermicomposting, anaerobic digestion
- Schemes: GOBARdhan, SATAT and Swachh Bharat
- Carbon terms: CCUS, BECCS, direct air capture, biochar
- Current affairs link: net zero plans and waste rules
- Common errors: saying that vermicompost is made without worms or that biogas is mainly carbon dioxide
As an analytical point, composting turns a waste problem into a soil and energy benefit, while carbon capture offers a way to cut emissions from sectors that are hard to clean. India needs both to meet its climate goals.
Why Is This Topic Important?
- Waste Composting methods
- Climate Capture techniques
- Schemes GOBARdhan
What Came Next?
The next topic covers bioprocessing, bioreactors and enzymes in the food industry. Next topic: Bioprocessing, Bioreactors and Enzyme Manipulation in the Food Industry.
Key People and Terms
- Compost Decomposed organic matter
- Vermicompost Worm made compost
- Biogas Methane rich gas
- CCUS Capture, use and storage of carbon
- Biochar Charcoal for soil
- Blue carbon Coastal carbon store
Exam Corner
Points to Remember
- Biogas is mainly methane.
- Vermicomposting worm: Eisenia fetida.
- GOBARdhan launched: 2018.
- India net zero target: 2070.
- Thermophilic phase is about 55 to 65 degrees.
Do Not Confuse With
- Compost and biogas digestate Aerobic product versus anaerobic residue
- CCS and CCUS Storage only versus use and storage
- Carbon capture and carbon credit Removing carbon versus a tradable certificate
Memory Hook
Heap with air, worm in the bed, digest without air; capture, use, store or plant.
Mains Angle
Questions ask about methods, schemes and climate links. These points help.
- Waste Segregation and compost
- Climate Capture options
- Policy Schemes and rules
A Question You May Face
An original practice question, not a past paper question.
“Discuss the role of bio-composting and carbon capture techniques in waste management and in meeting India’s climate goals.”
How to Answer
- Waste Composting.
- Carbon Natural and technology capture.
- Policy GOBARdhan, rules.
- Way Segregation, finance.
GS Relevance
Frequently Asked Questions
What is vermicomposting?
Vermicomposting is a method of making compost with earthworms, usually Eisenia fetida, which eat organic waste and release castings rich in nutrients. The product, called vermicompost, improves soil structure and plant growth. It is suitable for kitchen waste, farm residue and cattle dung and can be done at household and farm scale.
What is the difference between aerobic composting and anaerobic digestion?
Aerobic composting uses microbes that need oxygen and heat the pile, giving compost in weeks to months. Anaerobic digestion happens without oxygen in a closed digester and produces biogas, mainly methane, and a nutrient rich slurry. The first is used for manure, while the second also gives a fuel.
What is CCUS?
CCUS stands for carbon capture, utilisation and storage. It is a set of technologies that capture carbon dioxide from industrial gases or the air, then use it in products such as fuels or building materials, or store it permanently underground. It is considered important for hard to abate sectors like cement and steel.
What is biochar?
Biochar is a stable form of charcoal made by heating biomass, such as crop residue, with very little oxygen in a process called pyrolysis. When added to soil, it can hold carbon for hundreds of years and improve soil water holding and fertility, so it is both a soil improver and a carbon removal method.
What is the GOBARdhan scheme?
GOBARdhan, launched in 2018, is an Indian scheme to convert cattle dung, kitchen waste and agricultural residue into biogas, compressed biogas and organic manure. It supports clean cooking and energy and creates rural income, and is linked to the Swachh Bharat Mission and the SATAT initiative for compressed biogas.
PYQ Practice — Statement Analysis
1 Biogas consists mainly of methane.
Produced by anaerobic digestion.
2 Vermicomposting uses earthworms to decompose organic waste.
Eisenia fetida is common.
3 Biochar is made by burning biomass with excess oxygen.
It is made with little oxygen.
4 GOBARdhan was launched in 2018.
To turn dung into energy and manure.
Past Mains Questions on This Topic
This topic comes under Biotechnology – Applications. UPSC Mains questions asked on the matching syllabus topic, year-wise with marks:
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