SEPUR AN® GR EEN - 1,000 reference plant for efficient biogas upgrading
The Biomass Aggregation
Integration of Power-to-X Technologies in Biogas Plants
Landscape in India
22 In conversation with Mr. Alok Sharma
Fermented Organic Manure (FOM): A Vaue-Added Byproduct of the Biogas System for Sustainable Agriculture
Slurry valve for CBG projects: Planet Valves KGV
Anaerobic Digestion and Biogas Technology: Design, Challenges, and Applications
Reimagining Biogas Infrastructure for Liquid Fuel Synthesis under SATAT and Net-Zero Goals
Making of a Biogas Balloon – From Fabric to Function
“Dear Readers and esteemed members,
The past quarter has been exceptionally dynamic and rewarding for the biogas industry. We successfully hosted two impactful events that have significantly advanced our sector’s visibility and influence.
The first was the BBB Summit, which made headlines across the industry with the esteemed presence of Shri Nitin Gadkari ji, Hon’ble Minister for Road Transport and Highways, and Shri Santosh Kumar Sarangi ji, Secretary, Ministry of New and Renewable Energy. It was Supported by various embassies & industry leaders.The second highlight was the Bioenergy Pavilion at RenewX 2025 in Chennai, a major exhibition that drew an enthusiastic crowd from across South India. The pavilion served as a platform to showcase the potential of biogas and bioenergy.
Also, the Indian Biogas Association and Indian Oil Corporation have partnered to do advancement in the biogas sector.
In this edition, we focus on key topics that offer the latest developments in the sector. From engineering advancements to system-level upgrades, the entire value chain is being reimagined to meet the energy needs. One notable example is the development of biogas balloons—crafted with precision from fabric to full functionality—ensuring safe, efficient gas storage while highlighting the evolving technological depth of the sector.
Anaerobic Digestion and Biogas Technology continue to be at the core of this evolution, offering scalable solutions for waste management and renewable energy generation.
Aligned with India’s SATAT initiative and Net-Zero targets, infrastructure upgrades are enabling biogas plants to synthesize liquid fuels, expanding their role in clean mobility and energy diversification.
Reliable systems, including valves, ensure seamless flow management and sustained plant performance are critical for CBG projects’ long-term success.
Fermented Organic Manure (FOM), a nutrient-rich product, is emerging as a sustainable organic carbon enhancer, enhancing soil health and adding economic value for plant operators.
Looking forward, integrating Power-to-X technologies presents exciting possibilities. These innovations allow biogas plants to convert surplus renewable energy into storable fuels and chemicals, advancing energy security and grid resilience.
This edition captures these forward-looking developments and opportunities, encouraging collaboration and innovation toward a robust, circular bioenergy ecosystem in India.
Dr. A. R. Shukla President Indian Biogas Association
Chief Editor: Dr. Savita Boral
Editors: Abhijeet Mukherjee, Gaurav Kumar Kedia
Copy Editor: Mansha Tejpal, Dr. K. Rohit Srivastava, Lakshey Sehgal, Gautam Pandya
Creative Director: Jyoti Narang
Production: Shikhar Singh, Arjun Gambhir
Tech Support: Sangram Rout
Print Coordinator: Pawan
Sahoo Know us more
The “Indian Biogas Association” (IBA) is the first nationwide and professional biogas association for operators, manufacturers and planners of biogas plants, and representatives from public policy, science and research in India.
The association was established in 2011 and revamped in 2015 to promote a greener future through biogas. The motto of the association is “propagating biogas in a sustainable way”.
/biogasindia
/indianBiogasAssociation
/company/indian-biogasassociation/
IBA's Commitment to Advancing Industry Prospects for Biogas/Bio-CNG
- Period: April '25 - June '25
IBA's Presence at RenewX 2025: Powering the Bioener‑ gy Narrative
The Indian Biogas Association (IBA) made a significant presence by hosting the Bioenergy Pavilion at RenewX 2025, held from 23-25 April at the Chennai Trade Centre. Where IBA played a major role in shaping the bioenergy ecosystem, not only by hosting the Bioenergy Pavilion on the exhibition floor but also by powering a dedicated conference session on the Bioenergy and Bio-Hydrogen Revolution as well as Biogas policies and their economic impact.
The Indian Biogas Association (IBA) provided a platform for leading organizations in the bio-
energy sector across southern India, with the IBA itself serving as a key attraction within the exhibition. The exhibition showcased various technologies and solutions, including biogas digesters, biomethane systems, biomass dryers, and biofuel innovations. The pavilion provided a platform for industry serving in the bioenergy field by creating an ecosystem where consultants, project developers, and investors could engage directly with technical experts and solution providers of bioenergy.
Complementing its exhibition effort, IBA also hosted a high-impact conference titled 'Bio-energy Conference 2025,' featuring two insightful sessions. One on 'Bioenergy and the Bio-Hydro-
gen Revolution' and another one on 'Biogas Policies and Their Economic Impact,' offering valuable perspectives on the future of sustainable energy.
IBA’s contribution to RenewX 2025 aimed to amplify the voice of bioenergy on a platform shared with solar, wind, and e-mobility technologies. IBA successfully highlighted the essential role of biogas in India's transition to a greener, more inclusive energy future.
IOCL Collaboration with IBA: Advancing India's Bioenergy Mission
The Indian Biogas Association (IBA) has joined hands with Indian Oil Corporation Ltd. (IOCL) in a strategic collaboration to develop and expand the bio-energy sector. As one of the country’s leading energy companies, IOCL’s partnership with IBA will bring together industrial strength and sectoral expertise to create an ecosystem for biogas, compressed biogas (CBG), and related technologies. The partnership brings together active interaction with legislators, business executives, industry
players, and think tanks to develop knowledge centers.
This collaboration takes place because of the synergy between both organizations on the R&D efforts in the field of biofuels, with a special emphasis on industry-institute collaboration. The collaboration mainly focuses on the bioenergy and bio-hydrogen sectors.
By combining IOCL’s extensive distribution network and infrastructure with IBA’s deep sectoral expertise, the partnership is helping bridge the gap between policy and practice for bioenergy and bio-hydrogen. The joint efforts are expected to contribute to India’s bioenergy sector.
Together, IBA and IOCL are united by a shared vision: enabling a cleaner, greener, and economically inclusive future powered by indigenous bioenergy resources.
Collaborative Efforts: IBA, Indus Exposium, and Reveil le Energy Organize the BBB Summit
On May 8–9, 2025, IBA and Indus Exposium jointly hosted the BBB Summit—The International Summit on Bioenergy Value Chain at Hotel Le Méridien, New Delhi. With Reveille Energy as the Strategic Partner. With the theme “Fostering Transition Towards a Viksit Bharat,” the twoday summit brought together national and international stakeholders to shape the future of
India’s bioenergy sector through deep discussions, policy forums, and business networking.
The event was supported by the Ministry of Road Transport & Highways (MoRTH), and the MNRE. International support came from multiple embassies, including the Embassy of Brazil and the Embassy of the Netherlands, as well as from the U.S.-India Business Council (USIBC), all of whom served as country partners.
Held under the guidance of Shri Bhupinder Singh Bhalla, IAS (Retd.), former Secretary of MNRE, and inaugurated by Chief Guest Hon’ble Shri Nitin Gadkari, Minister of Road Transport & Highways, in the presence of Shri Santosh Kumar Sarangi, Secretary, MNRE, the summit emerged as a premier platform for advancing India’s bioenergy and biofuels agenda. The sessions addressed critical themes including compressed bioenergy, biofuels, and biomaterials, focusing on Boilers and Biomass Densification (Briquetting & Pelleting), Biofuels: CBG, SAF, E2G, Green Hydrogen, Biomaterials, and Circular Bioeconomy.
At the summit, one full day was dedicated to bioenergy, while the second day focused on biofuels and biomaterials. The prestigious JEEV Awards were also presented to companies making significant contributions to these sectors, with IBA being honoured as one of the recipients.
The summit featured multiple thematic sessions over the two days. It began with “Bioenergy Space in Bharat—Current Challenges and Future Opportunities,” followed by sessions such as “From Farm to Furnace to Field” and “Bugbears in the Bioenergy Sector,” which explored real-world challenges and opportunities in India’s bioenergy journey.
Day two addressed critical themes including “Biofuel: A Critical Pathway to Net Zero 2070,” “Biomobility: Revolutionizing Global Transportation,” and “Advanced Materials: Innovation and Applications.” Each session offered insights into how innovation and sustainability can propel India toward its sustainable development goals.
The summit also featured a ministerial roundtable and panel discussions featuring senior government officials, global thought leaders, and prominent big industry players who offered insights on scaling bioenergy adoption to meet national energy and climate goals.
IBA’s collaboration with Indus Exposium and the strategic planning by Reveille Energy ensured not only the seamless execution of the event but also promoted sustainable and inclusive energy solutions. The BBB Summit reinforced the bioenergy sector’s critical role in achieving energy independence, empowering rural economies, and driving India’s transition to a cleaner, greener, and self-reliant future.
IBA Supporting Event on CBG: Participation in Biofuel Expo
The Indian Biogas Association (IBA) actively participated in the Biofuel Expo 2025, held from 4–6 June, 2025, at the India Expo Centre in Greater Noida,
Reinforcing its commitment to supporting the growth of compressed biogas (CBG) and sustainable fuel solutions in India. As a supporting partner of the event, IBA extended logo support and marked its presence on the exhibition floor. The expo served as a platform for stakeholders across the biofuel value chain to exchange ideas, technologies, and experiences. Following its impactful presence at the Biofuel Expo, IBA is set to further its engagement with the industry through upcoming flagship events and initiatives. The Indian Biogas Association (IBA) will be hosting the Bioenergy Pavilion at the upcoming REI Expo 2025, taking place from 30th October to 1st November at the India Expo Mart, Greater Noida. We warmly welcome you to be a part of this and join us in showcasing the future of bioenergy.
Agitator Technology from Germany – ‘Made in India’
AGITATOR TECHNOLOGY FOR THE BIOGAS INDUSTRY
PRG Agitators Pvt. Ltd., located in Vadodara, is a 100% subsidiary of a German Multinational.
We have successfully installed agitators for 700+ biogas plants worldwide and boast over 20 years of experience in the biogas industry. We provide a diverse range of sophisticated agitator types that can be perfectly adapted to the respective task and system size –for optimum yields and maximum operational reliability right from the start.
Our product range includes:
• Central Agitators
• Paddle Mixers
• Lateral Agitators
Contact us to find the perfect mix for you.
PRG Agitators Pvt. Ltd.
66 Alindra, Savli GIDC, Manjusar, Vadodara, 391 775 Gujarat, India
Phone: +91 63549 16014
Email: info@prgagitators.com
PRG Präzisions-Rührer GmbH
Anton-Böhlen-Straße 13 34414 Warburg, Germany
Phone +49 (0) 5641 9006-0
Email info@prg-gmbh.de
Visit us at: www.prg-agitators.com
Integration of Power-to-X Technologies
in Biogas Plants
Introduction
Within a context of climate urgency and the energy transition, biogas plants stand out as key players. Starting from organic waste, they not only generate biomethane and energy but can also evolve through the integration of Power-to-X (PtX) technologies. These technologies make it possible to store renewable electricity (solar, wind, hydro, or geothermal) and convert it into advanced energy carriers such as hydrogen, methanol, or high-value synthetic fuels. This synergy represents a concrete opportunity to accelerate the transition toward a carbon-neutral energy system.
1.1 Where does CO₂ in Biogas come from?
CO₂ comes from the anaerobic digester of the biogas plant, which transforms organic waste. This carbon was recently in the atmosphere, so its re-emission does not increase the long-term net CO₂.
1.2 Is the CO₂ released to the environment or captured?
It is not released directly. During upgrading, the CO₂ is separated and concentrated in a purified stream. It can then be:
•Captured and reused, for ex-
ample, to feed reactors for methanation, methanol, or ammonia (Power-to-X).
•Liquefied or purified for industrial uses such as beverages, fire extinguishers, or horticulture.
•Geologically stored (bio-CCS) or converted into solid materials, generating net negative emissions.
1.3 And its climate impact?
•Recycled biogenic CO₂ returns carbon to the atmosphere in a short cycle, neither increasing nor decreasing it (neutral balance).
•If it is used or stored, it can provide negative emissions, helping mitigate climate change.
•In addition, biogas upgrading avoids methane emissions—25 times more potent than CO₂— thus reducing global warming.
What is Power‑to‑X technol ogy (PtX)?
Power-to-X technologies encompass a family of processes that convert green electricity (from sources such as solar, wind, hydro or geothermal) into energetic chemical compounds. The “X” in PtX represents products such as hydrogen (H₂), syn-
thetic methane (CH₄), methanol (CH₃OH), e-diesel (synthetic diesel or renewable diesel), e-kerosene (electro-kerosene), green ammonia (NH₃), dimethyl ether (CH₃OCH₃), synthetic gasoline (CnH₂n+2), among others.
How are Biogas Plants and Power‑to‑X Technology (PtX) related?
Let’s explain this with an example of integration with Power-to-X:
2.1 Power to Methane (Methanation)
• Green hydrogen (H₂) is produced via electrolysis with solar or wind energy.
• This H₂ is combined with biogenic CO₂ in a reactor (chemical or microbial) to generate synthetic methane (CH₄) and water.
• Result: more renewable-quality gas is obtained, supplementing the existing biomethane and reducing emissions.
2.2
Power to Methanol
• The same green H₂ and plant CO₂ are synthesized to produce green methanol (CH₃OH).
• It is a liquid fuel, easy to store and transport, ideal for maritime transport and aviation.
2.3 Power to Ammonia
• Using renewable H₂ and nitrogen (from the air), green ammonia (NH₃) is produced, applicable in fertilizers or as a fuel in industries and ships.
3. Key benefits of this inte
2.4 Products that can be generated beyond methane and their main application:
Product (X) Formula / Mixture PtX production process Main application
Green hydrogen H₂
Synthetic methane (SNG) CH₄
Methanol CH₃OH
Dimethyl ether (DME) CH₃OCH₃
E‑diesel / FT fuels Liquid hydrocarbons
Synthetic gasoline CnH₂n+2
E‑kerosene CnH₂n‑1
Green ammonia NH₃
Water electrolysis with renewable electricity
Methanation of H₂ + CO₂ (Sabatier or biomethanation)
Energy, industry, transport, chemicals
Pipeline injection, heat, fuel
Synthesis from H₂ + CO₂ Fuel, solvent, chemical feedstock
Catalytic dehydration of methanol (or from syngas + Fischer‑Tropsch)
Fischer–Tropsch from syngas (H₂ + CO)
Fischer–Tropsch or methanol‑to‑gasoline conversion
Urea CO(NH₂)₂ From NH₃ + CO₂ Fertilizers, chemical industry
Formate HCOO⁻ / HCOOH
Acetic acid CH₃COOH
Ethylene C₂H₄
Electro‑synthesis from H₂ + CO₂
From ethanol or synthetic methanol
Catalytic conversion of CO₂ + H₂
Hydrogen carrier, preservative
Chemical industry, solvent
Plastics, solvents
Propylene C₃H₆
Syngas CO + H₂
Conversion from syngas or ethylene Plastics industry
Water electrolysis + CO₂ (with SOEC) or catalytic reforming
Base for methanol, FT, ammonia gration:
• Carbon circularity: The captured CO₂ is reused instead of emitted.
• Renewable energy storage: Excess electricity is converted into usable gas.
• Flexibility and efficiency: You can choose to produce methane, methanol or ammonia according to demand.
• More sustainable local econ omy: Clean fuels are created at the same biogas plant, leveraging existing infrastructure.
4. In summary:
• Biogas plants generate CO₂ and CH₄.
• PtX technology converts CO₂ into high-value products such as renewable methane, methanol and ammonia.
• This maximizes energy utilization, reduces emissions and diversifies production at the same facility.
5. Time perspectives:
Regarding the time horizon, various international sources— such as the International Energy Agency (IEA) and the European
Commission—estimate the following:
• 2025–2030: pilots and first integrations in plants with renewable infrastructure.
•2030–2040: commercial expansion of e-fuels and PtX in strategic sectors.
•2040–2050: progressive substitution of fossil fuels, consolidating PtX as key in synthetic supplies.
6. Which energy source has the greatest potential to re‑ place oil?
It depends on the time horizon and the sector considered:
•Immediate: natural gas and liquid biofuels such as bioethanol and biodiesel, due to their compatibility with existing infrastructure.
• Short term (upto 2030): green hydrogen and renewable electricity (solar and wind), especially in light transport and industrial processes.
• Medium-term (2030–2040):
e-fuels (methanol, e-diesel) and green ammonia for aviation and maritime transport.
• Long term (2040+): 100 % renewable grids with large-scale storage (batteries and hydrogen), and sustainable bioenergy use in specialised niches.
7. Conclusion
The integration of PtX in biogas plants represents an innovative and realistic solution for the energy transition. It leverages mature technologies, abundant waste and renewable electricity to generate multiple sustainable energy vectors. The recommendation is clear: invest, experiment and scale up this technological convergence without delay.
Meet the Author
Oscar Morillo MSc. BSc. Oscar Morillo PE (T&T) Senior Civil/Structural Engineer Independent Biogas Researcher
The Biomass Aggregation Landscape
in India
India has traditionally been an agriculture-based economy with more than 65% of its population still dependent on agri and allied activities. Nearly 200 million ha of land is presently under cultivation with annual agri residue of approx. 500 million MT. This agri residue treated as waste, is either mulched in-situ or burnt in the field. Stubble/Parali burning, especially paddy straw, has been a critical concern for quite some time as it has an adverse impact on climate, health, soil condition and so on.
However, nowadays agri-residues are collected and processed in various forms like bales, silage, pellets, briquettes and so on subject to end-use requirements like fodder, biogas, biofuel, densified fuel, organic manure etc. Aggregation of agri
residue is a nascent industry. To be successful, requires enterprises to be resourceful, skilled and thoughtful. The aggregation ecosystem needs to be developed together with agencies providing easy and affordable finance, skill training of operators, outreach to farmers and FPOs, and so on
Policy drive:
Various policy measures have been taken by the Government to push biomass aggregation. The Government of India and a few state Governments have launched several schemes to subsidize plants and machinery engaged in aggregation and processing. One such scheme is SATAT where both public sector and private institutions are encouraged to set up CBG (Com-
pressed Biogas) plants throughout India. The govt aims to set up 5000 such plants in India. This step is aimed at addressing the pollution challenge and creating a complimentary source of biogas as a Sustainable Alternative Towards Affordable Transportation. This will have a direct impact on the reduction in crude oil import, fiscal deficit & inflation control, forex outflow and other macroeconomic issues. To promote the aggregation of biomass CRM scheme (Crop Residue Management) has been launched in six states to provide capital subsidies to farmers, FPOs, and local entrepreneurs in machinery purchase. Punjab, Haryana, and UP are leading states in biomass aggregation. The government is also providing subsidies and incentives under the GOBARDhan scheme for the offtake of the biogas.
Process:
Paddy straw is a high-volume and relatively low-value product. It is therefore compressed into bales before being transported to the storage unit/processing centres This compression process requires a specialised set of equipment like Balers (Square/ round), Hay Rakes, Cutters and customised Trolleys (flatbeds as well as automatic) driven with tractors. The Cutters first cut the standing straw from above the ground and then they are raked in line using the Hay Rake. Thereafter the balers grab the straw, compress it with high
pressure and release it as bales. Round bales of 250-300 kg and small square bales of 25-20 kg are prevalent models in the market. These bales are then loaded onto the trolleys and sent to the storage units. Typically, in Punjab and Haryana conditions, a baler aggregates approx. 1500-2000 MT during 30-40 days period. The rest of the country witness only 50- 60% output of this.
Capex and Opex:
Balers are mostly imported. Nowadays, square balers are manufactured domestically. Capital costs of the machines, their transportation, spares, repair and maintenance are all capital intensive. A set of square baler (including a Hay rake and two trolleys) costs around INR25 Lakhs where whereas a set of round baler costs approx. 3540 Lakhs. Even though Government subsidies are available to farmers and entrepreneurs, their adoption remains minimal due to high investment, bureaucratic hurdles in financing and subsidy, lack of skill and awareness, fear of loss etc. A few Pvt companies and entrepreneurs
have come into this space. However, the availability of low-cost finance, equity investment, and equipment subsidies are limited. Apart from Capex, the operation incurs huge operational costs. Unless the material is sold off timely, cashflow issues are faced by the aggregators.
Time sensitivity:
The time available for the collection of biomasses is very limited, typically 25-30 days. The farmer would prepare his land for the next crop thereafter. This necessitates absolute planning of resources and preparedness beforehand. Equipment readiness, spares, breakdown support, availability of bale nets, trained operators, labourers etc must be planned adequately. The focus should be purely on the volume of production and haulage.
Manpower readiness:
Not many tractor drivers are trained to operate balers/hay rakes, multi-lever tractors, long and heavy loaded trolleys etc. Dependency on labour has always been a concern for square balers. Experienced human resources to supervise this activity is also remote. In Farmwatt, we are periodically conducting operators’ training with support from different Foundations and service providers to create skilled manpower for this industry. Agriculture and engineering graduates are offered hands-on training and offered jobs.
Transportation:
Given the voluminous nature of the product, it requires largesize tailor-made trolleys for haulage. Often it is a challenge to get tractor drivers with valid Driving licenses to ply other trolleys on the road. Transporting such large and loaded trolleys in the narrow countryside road or on the highways is always difficult and risky. No-entry restrictions, traffic challenges, local disruptions, and all other transport-related matters are to be addressed throughout.
Storage:
Bales collected during the season are stored in an open warehouse (Transit Collection Centres) to be delivered onwards at the buyer's location over the whole year. Land selection for warehousing is critical to minimise the risk of fire and waterlogging. Availability and selection of such land are often difficult and expensive. Capex is also high as the SOP requires proper fencing, weigh bridge installation, power supply and backup, fire safety measures, Portacabin &monsoon shed, CCTV, front loaders, tarpaulin covers and so on. Nor-
mally such storage units are preferred near the catchment area. Typically, each such unit is 10-12 Acre large to accommodate approx. 10000 MT of paddy bales.
Insurance:
Rain, waterlogging and Fire pose maximum risk. If the bales are highly compressed with moisture inside, it is likely to auto-ignite. Parali burning in nearby fields often spread through the wind. Maximum care has to be taken to avoid any kind of fire loss. Being a new concept and product, limited insurance options are available and the premium is often costly.
Challenges and Policy Mea sures:
This industry of biomass aggregation is nascent but promising. Who’s who of the Indian business houses like RIL, IOCL, BPCL, HPCL, IGL, GPS, Samsung, and many others have started estab-
lishing CBG plants throughout the country. Many professionals with diverse backgrounds and experience are now curious to contribute to building the ecosystem. While the industry would mature over time, specific policies and local support would facilitate its early establishment and future growth.
•Subsidy: Subsidy under the CRM scheme is available in Five states only. It should be extended to other states as well. Moreover, the subsidy is available to farmers, VLEs, WSHGs, CHCs, and the plant owners. However, the actual aggregation at a large scale can only be achieved by Professional start-ups willing to take up this challenge. All such promotional schemes should therefore be made available to such Start Ups.
•Local administration and Awareness Generation: Stubble burning is rampant and behavioural in nature. The administration must ensure that offenders are penalized for such practices. On the other hand, the local administration must also create awareness among the villagers and farmers to cooperate in waste aggregation.
•Transportation facilitation: Even though transporters comply with all traffic requirements and follow due care, during haulage, harassment by local police is rampant. Often it is stressful and discouraging to take up such activities that are
minimally rewarding but high on risk. The administration must ensure that the transporter with all compliances should not be unnecessarily harassed.
•Skill Development: The Government should allocate resources and agencies to offer vocational training to drivers to operate loaders, rakers, balers etc. Mechanics, technicians, supervisors, and field coordinators are required in large numbers to develop the ecosystem.
•Availability of Finance: This business is capital-intensive and tedious. The availability of easy, timely and affordable finance holds the key to the success of such enterprises. The Government should encourage banks and FIs to provide such financial support at reasonable interest. CSR funding may also be channelled for this cause.
Expected Outcome:
India imports nearly 85% of its crude oil — a major economic burden. India's reliance on fossil fuels is both environmentally and economically taxing. Bioenergy so produced and blended with fossil fuel, reduces import pressure, and forex outflow, and offers a renewable and cleaner alternative. This shift not only lowers emissions but also supports India’s long-term energy independence goals.
The benefits go beyond energy. The by-products of bioen-
ergy generation, including Fermented Organic Manure (FOM/ LFOM/PROM etc), are rich in nutrients and used as natural soil enhancers, restoring the fertility of farmlands and reducing the dependency on chemical fertilizers. This contributes directly to long-term agricultural sustainability.
Every biogas unit, every aggregating equipment, and every Napier grass farming unit creates new jobs for rural youth and women. This localized employment model strengthens communities and reduces migration to urban centres. Farmer Producer Organizations (FPOs) play a key role in the green energy value chain and it is a self-sustainable mode of business for the FPOs. Through partnerships, FPOs earn income by aggregating agricultural waste, storage and transport of the same thus diversifying their revenue streams and increasing prosperity.
Fermented Organic Manure is rich in organic carbon and recent step of government of India to consider it under carbonic fertilizer is encouraging for Industry. At the same time as a industry we must think of value added fertilizers from FOM so that farmers acceptance is enhanced.
Fermented Organic Manure (FOM) enhances soil health and crop productivity, along with reducing the dependence on synthetic fertilisers. The FOM, rich in organic matter and beneficial microbes, also reduces the loss of organic carbon, particularly in Indian soils in the intensively cultivated regions.
OPINION
Mr.
Incorporating fermented organic manure into Indian agriculture can significantly contribute to sustainable farming, improved crop yields, and environmental health. Efforts to raise awareness and infrastructure development are key to widespread adoption.
CBG plant helps in conversion of agrowaste in Green fuel and Organic manure. This organic manure reduces chemical fertilizer dependency as well as facilitates climate-resilient and regenerative agricultural practices in India.
Gunther Keinath, ARMATEC-FTS INDIA PVT LTD
Dr. Manoj Shrivastava, IARI
Dr. Vibha Dhawan, TERI
Mr. Bhimashankar Shetkar, National Dairy Development Board (NDDB)
1. India’s bioenergy sector is at a transformative juncture. How do you assess the current land scape of bioenergy in India, and what key drivers are shaping its growth?
India’s bioenergy sector is undergoing a major transformation, backed by strong policy support and growing investment. We’ve already achieved around 19.8% ethanol blending with petrol in May 2025, targeting 20% under the Ethanol Blending Programme. At the same time, the Sustainable Alternative Towards Affordable Transportation (SATAT) initiative of GoI aims to establish 5,000 compressed biogas (CBG) plants, with a goal of replacing 5% of natural gas
Dr. Sharma, Director (R&D) at Indian Oil Corporation (IndianOil), is a seasoned leader in India’s energy sector. A Chemical Engineering postgraduate from IIT Delhi and graduate of Gujarat University, he brings over 30 years of experience in the downstream oil and gas industry. He had served at the Centre for High Technology (CHT) under the Ministry of Petroleum & Natural Gas, where he led national initiatives in refining and alternative energy. Mr. Sharma serves on expert panels of NITI Aayog, MNRE, DST, and BEE, and is affiliated with IAHE and HAI.
Dr. Alok Sharma Director (Research and Development) Indian Oil Corporation
consumption by 2028–29. These plants are expected to produce 15 million tonnes of CBG per annum, which is about 40% of the current CNG consumption of 44 million tonnes per annum in the country. As per India's National Biofuels Coordination Committee, CBG Blending Obligation (CBO) will be voluntary till FY 2024-2025, and mandatory blending obligation would start from FY 2025-26. CBO shall be kept as 1%, 3% and 4% of total CNG/PNG consumption for FY 2025-26, 2026- 27 and 2027-28, respectively. From 2028-29 onwards, CBO will be 5%.
National Biofuels Coordination Committee has also set a target to blend 1% of Sustainable Avi-
ation Fuel (SAF) with jet fuel in 2027 and 2% in 2028 (initially for International flights).
Further, the National Green Hydrogen Mission aims to provide a comprehensive action plan for establishing a Green Hydrogen ecosystem and catalysing a systemic response to the opportunities and challenges in this sunrise sector. The Mission is expected to reduce a cumulative ₹ 1 lakh crore worth of fossil fuel imports by 2030.
2. IOCL has been a pioneer in driving clean energy innova tions through its R&D efforts. Could you share how IOCL R&D is contributing to the advance‑ ment of technologies in bio-
CNG, biomass valorization , or biohydrogen?
Indian Oil Corporation Limited (IOCL), through its dedicated R&D Centre in Faridabad and collaborative innovation ecosystem, is playing a pivotal role in advancing India’s clean energy mission. With a strategic focus on CBG/bio-CNG, biomass valorization, and biohydrogen, IOCL is not only developing indigenous green technologies but also deploying them at a commercial scale to facilitate a circular and low-carbon economy. Some notable contributions and technological developments include the following:
Compressed BioGas (CBG) technology
• A complete technology basket for CBG including the proprietary feed agnostic microbial blend (BioXeed), patented process (IBG-Plus) as well as innovative solutions for smooth operation of CBG plants including IBG-Booster for sustained biogas yields, IBG-F5 for feedstock quality management and IBGSRA for scum reduction and other troubleshooting options. Brief details of the IndianOil technology basket are as follows:
o BioXeed- A feed agnostic, robust, patented bioinoculant for increased biogas yield.
o IBG-Plus- A single-stage bio-methanation technology tailored to handle various types of feedstocks in a streamlined
manner. This innovation simplifies plant operations, reduces capital costs, and enhances overall efficiency.
3. Collaboration is key to accel‑ erating progress. How do you see strategic partnerships, such as the one with the Indian Bio gas Association, enabling faster adoption and innovation in the bioenergy ecosystem?
Strategic partnerships play a pivotal role in fostering innovation and accelerating the adoption of technologies in the bioenergy ecosystem. IOCL has done many collaborations with academic excellence as well as industrial partners to adopt, accelerate and establish the innovations in the area of the energy sector. These types of collaborations always have mutual benefit as well as societal benefit on a larger scale. Collaborations such as the one with the Indian Biogas Association (IBA) bring together complementary strengths of stakeholders from industry, academia, government, and startups, leading to a more holistic and coordinated approach toward clean energy goals.
Major key benefits of such collaborations in enabling faster adoption and innovation include:
• Partnerships allow for rapid sharing of emerging technologies, best practices, and pilot-scale results. For example, IBA can bring together its pan-India network of CBG (Com-
pressed BioGas) stakeholders onto a single table, for the faster upgradation of the CBG technology.
• Collaborative efforts with bodies like the IBA help in shaping favourable policies, creating unified standards, and addressing regulatory bottlenecks. This facilitates a smoother rollout of technologies across regions.
4. What are some of the most promising bioenergy technol‑ ogies or pathways that IOCL is currently exploring or support ing through pilot or scale-up projects?
IOCL’s bioenergy strategy is ambitious and holistic, spanning second- and third-gen biofuels, carbon capture & utilization, CBG upscaling, hydrogen transition including mobility sector, and waste valorization. With several pilot plants already in operation or nearing scale-up, these projects are accelerating India’s energy transition while supporting farmers, generating rural jobs, and reducing emissions. IOCL R&D is also looking at the possible solutions of biorefinery and circular economy options to meet the net zero targets without compromising on the rising energy demand and changing energy landscape.
CBG technology has been commercially implemented at different locations across India. A 100 TPD cattle dung-based plant is operational in Jaipur, Rajasthan, demonstrating efficient
conversion of organic waste into CBG. Similarly, a 200 TPD paddy straw-based plant in Gorakhpur, Uttar Pradesh, highlights the scalability of IndianOil’s technology in utilizing agricultural residues. Additionally, a 100 TPD cattle dung-based plant is under commissioning in Gwalior, Madhya Pradesh, further reinforcing IndianOil’s commitment to expanding green energy infrastructure. These projects exemplify IndianOil’s robust and feedstock-agnostic technologies, which optimize resource utilization for sustainable CBG production, aligning seamlessly with India’s SATAT initiative.
5. Given your experience at the intersection of research, policy, and implementation, what are the critical policy or infrastruc ture gaps that still need atten tion for India to fully unlock its bioenergy potential?
India has tremendous bioenergy potential, but to fully unlock it, certain critical enablers need urgent attention. First, we need a more integrated policy framework under a single unified national mission. Second, there’s a pressing need for organized biomass supply chains and robust logistics infrastructure, especially to support 2G ethanol and CBG projects. Third, the viability of bioenergy projects depends on financial innovations, like offtake guarantees and viability gap funding. On the technology front, we must create real-world validation platforms to fast-track promising innovations from lab
to market.
Bioenergy sector, despite its promising potential, faces several hurdles that impede its largescale adoption. These challenges include feedstock availability and logistics, high capital investment, technological limitations, and market-related issues. The seasonal nature and dispersed geography of biomass sources make collection and transportation difficult, while the substantial initial investment in plant setup deters entrepreneurs. Technological challenges, such as managing feedstock variability and ensuring operational stability, further complicate plant operations. Additionally, the limited awareness about the economic and environmental benefits, coupled with the lack of established supply chains for by-products. Addressing these challenges requires a combination of technological innovation, policy support, and capacity-building initiatives.
Finally, stronger integration of farmers, government bodies and industries is key. If we can bridge these gaps, biofuels/bioenergy can play a transformative role in India’s clean energy transition.
6. Looking ahead, how do you envision the role of bioenergy within India’s broader future energy mix, particularly in the context of achieving net-zero targets and energy security?
Looking ahead, bioenergy will play a vital and strategic role in
India’s future energy mix, particularly in achieving our net-zero ambitions and strengthening energy security. Unlike intermittent renewables, bioenergy offers a dispatchable, carbon-neutral alternative that integrates well with existing infrastructure and supports rural economies.
At IndianOil R&D, we view bioenergy not just as a fuel, but as a key pillar in the circular economy, converting agri-residues and wastes, organic waste, and industrial emissions into valuable energy carriers like ethanol, CBG, other biofuels such as SAF, and even green hydrogen. This directly addresses our twin goals of decarbonization and import reduction.
Moreover, with the right policy push and scale-up mechanisms, bioenergy can create decentralized energy access, generate rural employment, and provide a sustainable pathway for sectors that are hard to electrify, such as heavy transport and industry. In essence, bioenergy will be a bridge, linking India’s development needs with its climate commitments.
Fermented Organic Manure (FOM):
A Value-Added Byproduct of the Biogas System for Sustainable Agriculture
ABSTRACT
The creation of clean energy and sustainable waste management are two advantages of integrating biogas systems into agriculture. Fermented Organic Manure (FOM), a nutrient-rich, humus-based fertilizer made from anaerobic digestion and aerobic fermentation of organic waste, is one of the system's main value-added outputs. FOM strengthens the soil, and lessens the need for chemical fertilizers.
By turning municipal and agricultural waste into valuable inputs, it also plays a critical role in advancing climate-smart agriculture and reaching zero-waste targets. FOM is a scalable and eco-friendly option for Indian farming systems, bolstered by recent technical advancements and national policies.
The agriculture industry is confronted with two challenges: the responsible management of organic waste and the preservation of soil fertility. In addition to providing a clean energy source, the development of biogas technology creates digestate, which can be converted into Fermented Organic Manure (FOM) with the right processing. FOM is a powerful biofertilizer that embodies the fundamental ideas of a circular bioeconomy, which closes the gap between production and consumption by turning organic waste into nutrient-rich fertilizer and sustainable energy [1,2].
2. Biogas Systems and FOM Production
Anaerobic digestion (AD), the process by which methanogenic bacteria break down organic materials like animal dung, agricultural residues, and food waste in an oxygen-free environment, is the basis for how biogas plants work. The process produces digestate and biogas, primarily methane and CO₂ [1,3]. The digestate develops into FOM, a stable, pathogen-free, and humus-rich organic amendment, after undergoing additional regulated aerobic or semi-aerobic fermentation.
3. Composition and Proper ties of FOM
Parameter
C:N Ratio
pH
Microbial Load
12:1 to 18:1
Neutral to slightly alkaline
High; includes Bacillus spp., Trichoderma, Rhizobium
4. Agricultural Benefits of FOM
FOM improves soil fertility both immediately and over time by acting as a slow-release organic fertilizer. Following are some of its contribution:
1. Enhances moisture retention and soil structure.
2. Raises microbial activity and organic matter.
3. Provides macro- and micronutrients in balance.
4. Lessens reliance on artificial inputs, which lowers expenses and improves the sustainability of soil health.
Figure 1: Biogas production and its application
Table 1: Physico-Chemical and Microbial Characteristics of Fermented Organic Manure (FOM)
Field studies have shown that FOM application can increase crop yields by 15–30%, particularly in cereals, pulses, and horticultural crops [4].
5. Role in Waste Manage‑ ment and the Circular Econ‑ omy
FOM supports the objectives of climate-smart farming and zero-waste agriculture by turning organic waste streams from cities and farms into a useful product. FOM-producing biogas systems aid in mitigating:
3. Overuse of landfills for municipal and food waste
The Sustainable Development Goals (SDGs) of the UN, such as soil conservation, clean energy, and responsible consumerism, are directly impacted by this nutrient recycling [5].
6. Technological Advance‑ ments in FOM Handling
The manufacturing and use of FOM have been enhanced by recent innovations:
1. Slurry separation units separate digestate into liquid and solid components for specific uses.
2. Granulation and pelletizing equipment facilitate the storage
and transportation of FOM.
3. Treatment facilities are delivered right to the field by mobile FOM fermenters.
4. Composting with sensors guarantees ideal conditions for microbial fermentation.
These developments are essential for expanding the use of FOM in smallholder agriculture, which frequently lacks access to extensive composting facilities. [6]
7. Case Studies and On‑ Ground Impact
FOM is applied to vegetable crops by more than 50 farmers in Ahmednagar, Maharashtra, who use home biogas units. Results indicate a yield improvement of up to 28% and a 30% decrease in chemical input costs.
Kangra, Himachal Pradesh: With better soil health indicators, the need for synthetic fertilizer in apple orchards has decreased by 40% as a result of community biogas facilities that provide
Biogas Magazine | Edition 32
both cooking gas and FOM. [7] According to research from Punjab Agricultural University, applying FOM to wheat and maize enhances microbial biomass and root development more than using standard FYM (farmyard manure).
8. Policy Support and Institu tional Framework
The government of India aggressively promotes the merger of FOM and biogas by:
1. New National Biogas and Organic Manure Programme (NNBOMP)
2. Under the Swachh Bharat Mission, the GOBAR-DHAN Scheme
3. To encourage the use of organic inputs, the Paramparagat Krishi Vikas Yojana (PKVY)
4. Financial rewards for commercial and community-scale biogas facilities that generate FOM
9. Challenges and Way Forward
Challenges Suggested Solutions
Lack of awareness Farmer training & demonstration farms
CONCLUSION
A sustainable and valuable byproduct of the biogas system, fermented organic manure (FOM) provides a comprehensive answer to the problems of soil fertility and organic waste management in agriculture. It is a viable substitute for chemical fertilizers because of its nutrient-rich makeup, slow-release characteristics, and microbial advantages. By incorporating FOM into farming systems, we may improve soil health and crop yield while simultaneously advancing a circular economy strategy that supports climate-resilient and zero-waste farming objectives. Government initiatives, technological advancements, and real-world success stories further support its practicality.
REFERENCES
1. Jameel MK, Mustafa MA, Ahmed HS, jassim Mohammed A, Ghazy H, Shakir MN, Lawas AM, khudhur Mohammed S, Idan AH, Mahmoud ZH, Sayadi H. Biogas: Production, properties, applications, economic and challenges: A review. Results in Chemistry. 2024 May 20:101549.
2. Srivastava A. A Review On Biogas: Sustainable Energy Source For India. International journal of creative research thoughts. 2024;12:639-48.
3. Sileshi G, Barrios E, Lehmann
J, Tubiello FN. Organic matter database (omd): Consolidating global residue data from agriculture, fisheries, forestry and related industries. Earth System Science Data Discussions. 2023 Oct 10;2023:1-46.
4. Verma M, Singh P, Dhanorkar M. Sustainability in residue management: a review with special reference to Indian agriculture. Paddy and Water Environment. 2024 Jan;22(1):1-5.
5. Li P, Zhao M, Zhang H, Zhang O, Li N, Yue X, Tan Z. An Operational Optimization Model for Micro Energy Grids in Photovoltaic-Storage Agricultural Greenhouses Based on Operation Mode Selection. Processes. 2025 May 22;13(6):1622.
6. Garkoti P, Thengane SK. Techno-economic and life cycle assessment of circular econo-
my-based biogas plants for managing organic waste. Journal of Cleaner Production. 2025 May 1;504:145412.
7. Assandri D, Cavallo E, Tamagnone M, Pampuro N. Performances of methane-powered crawler tractor tested in stationary and field conditions. Energy Conversion and Management: X. 2025 Apr 22:101031
Meet the Author
Er. Ramesh Chand
Assistant Professor, Department of Agriculture
Maharishi Markandeshwar (DEEMED TO BE UNIVERSITY) Mullana
Dr. Ridhima Arya
Assistant Professor, Department of Agriculture
Maharishi Markandeshwar (DEEMED TO BE UNIVERSITY) Mullana
Dr. Stuti Pathak
Assistant Professor, Department of Agriculture
Maharishi Markandeshwar (DEEMED TO BE UNIVERSITY) Mullana
Slurry valve for CBG projects:
Planet Valves KGV
A knife gate valve is a type of gate valve and is primarily designed for isolation and on-off services in systems with highly suspended particle contents. The main features of knife gate valve include simple structure, good sealing performance, corrosion resistance, and flexible operation.
Knife gate valves are designed to cut through thick fluids and solids. Hence these are commonly used in CBG plants, mining, coal washing, steel industry, pulp & paper industry, power plant ash removal, purification system etc. They’re known for their sharp gates, which make them ideal for handling abrasive materials.
The straight-through design of the knife gate valve minimizes pressure drop across the valve, which enhances slurry flow control. This is essential in applications where maintaining a consistent flow rate is crucial for operational efficiency.
Knife gate valves should only be used for applications that require a completely open or completely closed position, and should not be used to regulate flow unless they are specifically intended for that purpose. A vibration occurs whenever fluid is pressed against a partially closed gate, progressively eroding the disc and seat.
Knife gate valves are categorized by their design, which directly impacts their functionality and suitability for various applications.
Unidirectional knife edge gate valve- Unidirectional valves are designed to allow flow in one direction and seal effectively against any reverse flow. These valves are ideal for applications where backflow prevention is necessary like wastewater treatment, mining, and pulp & paper industries etc.
Bi-directional knife edge gate valve- Bi-directional Knife Gate Valves are capable of controlling the flow in both direc-
tions. This adaptability makes them well-suited for dynamic applications like CBG, power plants, chemical processing, food production etc. offering enhanced performance in varying conditions.
Several factors need to be considered when selecting a Knife Edge Gate Valve, in‑ cluding,
1. Nature of fluid & required flow rate: The valve should be able to handle the fluids, Pulp, Powder, slurry or solids.
2. Flow direction: Find out whether the specific application will need a uni-directional or a bi-directional valve.
3. Operating Conditions: Make sure the valve is able to withstand operating pressure, temperature and required flow rate.
4. Actuation Method: depending on your operational needs choose from manual, pneumatic operation.
5. Valve size & pressure rating: Choose the right size and pressure class of the valve according to the service conditions that the valve will experience.
6. Material of construction: Knife Gate Valves are used in corrosive services; therefore, the selection of material of construction is an important factor, stainless steel or other suitable anti-corrosive materials.
Like any mechanical equipment, even the best-maintained valves fail, and knife gate, slurry valves are no exception. Being valves that generally handle tough media, they tend to fail more frequently than conventional valves due to a variety of reasons, often not easily predictable. Understanding the Solutions to common problems of Knife Gate Valves is key to preventing downtime and improving efficiency. However, detailed study and analysis of field failures can give us many pointers to take effective measures to extend service life.
The initial step is to evaluate their operational status to determine the nature of the malfunction. Thereafter, conduct a systematic investigation into potential causes following the observed symptoms. Common fault causes may include power
supply issues, actuator malfunctions, damaged seals and many more.
To reduce the occurrence of faults in knife gate valves, preventive measures should be taken. This includes selecting reliable valve products & manufacturers, ensuring proper valve installation, regularly conducting maintenance etc. Prioritize safety measures during the troubleshooting process to prevent secondary damage. Utilize measuring tools during the troubleshooting process to pinpoint the exact location of the fault more accurately. For different fault causes, corresponding troubleshooting methods should be employed.
Solutions to common prob‑ lems of Knife Edge Gate Valve:
1. Gland Leakage
Improper tightening of gland bolt causes water leakage during testing/use.
Solution:
• Remove the bolt from the gland hole, tighten it again diagonally
2. Valve body and gland joint leakage
Unequal tightening of flange bolts causes misalignment and can lead to subsequent leakage. Worn seals, damaged flange gas-
kets damage to the joint surface between the valve body and gland, damage to gland packing or insufficient gland packing etc. cause leakage at the joints. Using packing materials which are not suited to operating conditions may also lead to leakage.
Solution:
• During the installation of the valve, tighten the flange bolt evenly and diagonally to ensure proper alignment and sealing.
• Use better quality gaskets & gland packing.
• Check the seals periodically for any damage or wear and replace the same if required.
• Consider parameters like temperature, pressure, and nature of fluid while selecting the packing material, sealing material etc.
3. Stem sticking
Inadequate clearance between the stem and the bushing may lead to increased friction and operational difficulties. Apart from this, excessive packing compression, improper material selection for the valve stem and bushing, tortuous stem, applying excess force during operation, improper filling of packing into the stuffing or packing box, rough surface finish of thread etc. are the main reasons for stem sticking/jamming.
Solution:
• Maintain proper alignment/ clearance between valve stem and bushing to prevent operational difficulties.
• Loosen the packing gland screws appropriately to ensure proper packing compression.
• Ensure appropriate material selection.
• Operate the valve gently and avoid excessive force. While opening the valve, avoid reaching the upper dead point, instead, stop before it and turn the handwheel back one or two turns to prevent the medium from pushing the valve stem upward.
• Maintain a smooth stem surface by addressing any damage to facilitate easier movement and control the roughness of the thread’s surface finish within the specification.
4. Gate Jamming
A variety of situations can cause the valves to jam and prevent operation or closing. Foreign materials or debris within the valve body obstruct the gate’s movement, leading to incomplete closing or jamming. Overtightening of the packing gland to arrest leakage can also cause the valves to jam. Mechanical wear and tear of internal components over time, improper installation, media settlement or solidification in the body cavity are the reasons for hindering the gate’s proper operation.
Solution:
• Ensure regular cleaning to remove debris and prevent blockages that could affect valve operation.
• Loosen the packing gland screws appropriately.
• Perform regular and appropriate lubrication of moving parts to facilitate smooth operation.
• Prefer the IOM (Installation, Operation and Maintenance) manual while installing and regularly inspect and adjust the alignment of valve components to ensure proper functioning and prevent jamming.
5. Seat Damage or Erosion
Inappropriate valve selection for the application and handling of abrasive substances causes undue stress, and wear and tear on the valve seat over time. Also, extreme temperature exposure may lead to thermal stress resulting in seat damage.
Solution:
• Check and confirm the compatibility of seat material with the specific fluid or slurry being handled.
• Check and confirm compatibility of seat material with design temperature.
• Periodically inspect for signs of seat erosion or wear and replace damaged seats.
6. Pneumatic / Electric Actu‑ ation difficulties
There are many reasons which may affect the performance of the actuator and ultimately the valve, insufficient or excessive supply of air or electricity, overloading & improper sizing of the actuator, worn-out actuator components, lack of lubrication or maintenance, load misalignment etc.
Solutions:
• Verify that the actuator is receiving the correct supply pressure or voltage.
• Match the actuator type (manual, pneumatic, electric) and size to the application requirement.
• Replace worn-out components and conduct regular performance checks.
• Regularly lubricate moving parts to prevent wear
• Re-align the cylinder and load.
In conclusion, the knife gate valve’s working principle revolves around its ability to efficiently handle thick, viscous, or solid-laden fluids by utilizing a sharp-edged gate. The advantages of precise flow control, minimal pressure drop, and suitability for abrasive fluids make Knife Edge Gate Valves indispensable in applications where reliability is non-negotiable.
While Knife Edge Gate Valves are known for their low maintenance requirements, regular inspection and preventive maintenance are essential to ensure their optimal performance. Addressing common knife gate valve issues such as stem failure, leakage, jamming, and corrosion through targeted solutions like proper material selection, regular lubrication, correct installation, periodic checks for wear and erosion and operator training significantly enhances operational efficiency and extends the valve’s lifespan. Additionally, following the manufacturer’s maintenance guidelines and conducting routine tests can help mitigate potential issues.
When choosing to use knife gate valves, it is important to weigh their advantages and disadvantages based on actual working conditions and requirements to ensure the normal operation and efficient use of the equipment.
Ms. Divya Raut-Gejge Design & QC Head
Anaerobic Digestion and Biogas Technology:
Design, Challenges, and Applications
8. Biogas Flaring: Design and Operational Considerations
Biogas flaring is a critical safety measure for managing surplus biogas when energy recovery is not feasible, ensuring the safe combustion of methane to prevent environmental hazards and mitigate the risk of fire or explosion, particularly when methane concentrations are between 5% and 15% in air. The flaring process involves the oxidation of methane in an open flame, converting it into carbon dioxide, which has a significantly lower
Article of Edition 31
global warming potential compared to methane.
Combustion Process
The complete combustion of methane requires two moles of oxygen per mole of methane, as described by the equation:
CH4+2O2→CO2+2H2O
In practice, achieving complete combustion involves providing excess air, typically 10 volumes of air per volume of methane, to ensure thorough oxidation and cool the flame.
Design Considerations
The design of biogas flares is influenced by the composition of the biogas and its flow rate. The air requirement for combustion and the flow rate determines the height of the flare, velocity, and residence time of the biogas within the flame. Enclosed flare systems are preferred over open systems due to their ability to maintain uniform burning conditions, prevent quenching, and meet performance and emission standards. These systems often include air dampers to control combustion temperature, enhancing safety and environmental compliance.
9. Operational and Safety Aspects
Before operation, a thorough flare inspection is necessary to ensure proper installation and safety. This includes leak detec-
tion in the gas supply pipe network to prevent accidents and minimize thermal and noise emissions from flaring. Regular maintenance is crucial to maintain the integrity of the flare system and ensure continuous safe operation.
10. The design of a biogas plant
The design of a biogas plant hinges on optimizing reactor volume and operational parameters to balance efficiency, stability, and economic viability. Key considerations include:
Feedstock Analysis and Process Configuration
Design begins with evaluating feedstock quantity, quality (TS, VS content), and characteristics (wet/dry digestion). Future variations in feedstock availability and composition must be anticipated to ensure long-term plant adaptability. Co-digestion of multiple substrates is often incorporated to enhance biogas yield and process stability.
Reactor Volume Determination
Reactor volume is calculated using hydraulic retention time (HRT) and organic loading rate (OLR). HRT, the theoretical time substrates remain in the digester, is influenced by feedstock biodegradability, temperature (mesophilic: 30–40°C; thermophilic: 50–55°C), and reactor type (e.g.,
CSTR, plug-flow). Shorter HRTs (8–12 days) suit easily degradable substrates like sugars, while fibrous materials require longer retention (≥15 days) to prevent microbial washout. Multi-stage systems separate acidogenesis and methanogenesis phases to optimize conditions for distinct microbial communities.
Hydraulic Retention Time (HRT)
HRT is critical for microbial activity and substrate degradation. Excessively short HRTs risk VFA accumulation and methanogen inhibition, while overly long HRTs increase digester size and costs. Thermophilic conditions accelerate methane production but demand precise temperature control.
Organic Loading Rate (OLR)
OLR dictates the daily organic matter input per reactor volume. High OLRs boost biogas output but risk process instability due to VFA buildup and pH drops, which inhibit methanogens. Optimal OLR balances feedstock degradability, microbial capacity, and digester design. For recalcitrant substrates, lower OLRs (2–4 kg VS/m³/day) prevent overloading, whereas easily digestible materials tolerate higher loads (5–10 kg VS/m³/ day).
11. Design Optimization
Reactor sizing must account for
substrate degradation rates, microbial propagation, and operational temperature. Thermophilic digesters achieve faster degradation but require rigorous monitoring. Multi-stage configurations or pre-treatment (e.g., mechanical or thermal) improve hydrolysis efficiency for complex substrates like lignocellulosic biomass. Process stability relies on maintaining HRT-OLR equilibrium to avoid overloading or underutilization, ensuring consistent biogas production and system longevity.
12. Conclusions
Biogas technology faces significant challenges that limit its widespread adoption despite its potential as a renewable energy source. The high upfront investment costs, particularly for small-scale plants, deter farmers and investors due to long payback periods and competition with cheaper alternatives like diesel or grid electricity.
Additionally, operational and maintenance expenses further strain profitability, especially for advanced systems requiring specialized equipment. Biogas systems also lack efficiency and scalability, with limited advancements to simplify processes or reduce costs, and complex designs like lagoons demand substantial land. Not all organic waste is suitable for biogas production, and consistent feedstock supply is critical.
Furthermore, biogas struggles
against established renewables like solar, wind, and hydropower, which offer lower operational costs and broader scalability, and limited market demand for upgraded biogas further hampers adoption. Despite these limitations, biogas remains a unique solution for simultaneous waste management and energy generation, particularly in regions with abundant organic waste and aligned environmental goals.
Meet the Author
Mr. Mainak Ray Deputy Manager - R&D and Innovation HPCL- Mittal energy LTD
Membrane separators for Biogas upgrading and dehydration
Air Products Membrane Solutions specializes in the development of high-efficiency, high-productivity hollow fiber membrane separators for on-site gas generation systems, which could be used for biogas upgrading, biogas dehydration, hydrogen recovery, nitrogen generation.
Membrane manufacturing expertise since 1979
Proven track record of quality and reliability
Designed for high criticality application
Over 500,000 membranes in use in over 70 countries
We have many successful biogas upgrading and dehydration cases around the world. Please contact us (https://membranesolutions.com/contact/) for more information.
Reimagining Biogas Infrastructure for Liquid Fuel
Synthesis under SATAT and Net-Zero Goals
Introduction
India’s pledge to achieve Net Zero emissions by 2070 and the national SATAT (Sustainable Alternative Towards Affordable Transportation) initiative have placed compressed biogas (CBG) at the heart of the country’s green energy ambitions. Presently, the focus of SATAT is predominantly on the injection of CBG into the transportation and industrial sectors. However, the rapidly evolving field of synthetic liquid fuels opens new and transformative opportunities. As sectors such as aviation, marine transport, and heavy industries face rising decarbonization pressure, biogas offers an adaptable and carbon-neutral feedstock
for the synthesis of Sustainable Aviation Fuel (SAF), green methanol, and electrofuels (e-fuels). Rethinking India’s biogas infrastructure and moving beyond simple purification units to an integrated bio-refinery cluster can enable a shift toward high-value, liquid energy carriers. This article explores how biogas can be technologically and strategically leveraged under SATAT and national climate goals to support liquid fuel production.
From Biogas to Syngas: The Crucial Intermediary
Biogas, comprising roughly 60% methane (CH₄) and 40% carbon dioxide (CO₂), can be upgraded beyond direct combustion by
converting it into syngas a blend of hydrogen (H₂), carbon monoxide (CO), and CO₂ via reforming processes. Two major pathways dominate this conversion. Steam Methane Reforming (SMR) is a commercially mature and widely used technique where methane reacts with steam at high temperatures (700-1000°C), yielding CO and H₂. Despite its high energy demand, SMR can be integrated with a water-gas shift (WGS) reaction to tailor the H₂/CO ratio as per downstream needs. An equally compelling method is Dry Reforming of Methane (DRM), where methane reacts directly with CO₂ to produce syngas. This method aligns perfectly with biogas composition, utilizing both CH₄ and CO₂. However, the DRM process requires advanced catalyst systems to counter carbon deposition issues. The resulting syngas serve as a building block for synthesizing SAF, methanol, and other hydrocarbons, thereby enabling biogas to become a versatile forerunner for clean liquid fuels.
Biogas to Sustainable Avia tion Fuel (SAF )
India’s aviation sector is poised to triple by 2040, making low-carbon, drop-in fuels an urgent requirement. SAF produced through the Fischer–Tropsch (FT) synthesis route from biogas-derived syngas offers a viable solution. The FT process involves the catalytic reaction of H₂ and CO at 200-350°C and 2030 bar, producing long-chain hy-
drocarbons (C₈-C₂₀) suitable for jet fuel after hydrocracking and isomerization. These fuels match the specifications required for flash point, freezing point, and aromatic content for aviation use. The FT process currently operates at TRL 7-8, especially in centralized petrochemical settings. However, its adaptation for decentralized bio-refineries remains an emerging challenge due to cost, reactor miniaturization, and catalyst longevity. Modular scalability remains a key advantage, enabling SAF micro-refineries to be co-located with decentralized biogas plants under SATAT.
At the research organizations and universities, collabora tive research is underway ex ploring catalytic upgrading of biogas to liquid fuels, includ ing small-scale FT synthesis and DRM catalyst stabilization using transition-metal and perovskite-based systems. Pi lot-scale SAF production linked with anaerobic digesters is also being conceptualized. This distributed model of SAF production not only supports green aviation but also promotes rural employment, decentralized energy generation, and circular waste valorization, directly aligning with India’s socio-economic development priorities.
Biogas to Green Methanol: A Strategic Fuel and Feedstock
Methanol synthesized from syngas represents another high-value pathway, serving not only as
a marine fuel compliant with IMO 2020 standards but also as a base chemical for plastics, olefins, and hydrogen storage. Methanol synthesis occurs through the catalytic reaction of CO and H₂ (and CO₂ with H₂) over Cu/ZnO/Al₂O₃ catalysts at 200300°C and high pressures (50100 bar). Methanol synthesis is considered TRL 8 9, but biogenic syngas introduce variability in feed composition that demands robust gas conditioning. Optimal H₂/CO ratios (~2) are essential, which can be achieved through a combination of SMR, DRM, and WGS adjustments. India’s growing interest in green hydrogen can further amplify this value chain. By integrating solaror wind-powered electrolyzers with biogas plants, electrolytic hydrogen can be combined with biogenic CO₂ from digesters to co-synthesize methanol.
Challenges remain in coupling these systems economically, particularly regarding hydro gen availability and continu‑ ous CO₂ supply. Such integrated biogas-hydrogen platforms enhance the economic output per tonne of biogas while contributing to decarbonized fuel, chemical, and energy storage sectors.
Biogas in the e-Fuels Ecosys tem
Electrofuels, or e-fuels, are synthetic hydrocarbons created by combining green hydrogen with CO₂ closing the carbon loop. Biogas, inherently rich in biogenic CO₂, becomes an excellent can-
didate for this emerging sector. Through the Sabatier reaction, CO₂ from biogas can be converted to synthetic methane (SNG) using renewable hydrogen. Likewise, FT synthesis can be employed to convert H₂ and CO₂ or CO into liquid fuels such as e-diesel, e-gasoline, and e-kerosene. This model positions biogas digesters as dual-purpose units: generating renewable gas and capturing CO₂ for synthetic fuel synthesis.
Such integration redefines the CBG plant as a multi-output bio-refinery producing both gaseous and liquid fuels. This strategy creates synergies between biogas infrastructure, renewable electricity, and chemical conversion systems offering a scalable blueprint for carbon-neutral fuel production. The primary commercialization challenges lie in scale economies, investment costs, and policy incentives for fuel offtake.
Infrastructure and Policy Re imagination under SATAT
The SATAT scheme envisions 5,000 CBG plants generating 15 million tonnes of CBG annually. To move toward value-added liquid fuels, India must broaden SATAT’s scope.
Firstly, biogas plants should be designed or retrofitted with reforming units and syngas conditioning systems to enable downstream fuel synthesis. Modular FT and methanol reactors should be incorporated to facilitate on-
site or near-site liquid fuel production.
Cluster-based integration is also critical. Developing regional bioenergy parks that co-locate feedstock aggregation, anaerobic digestion, reforming, electrolyzers, and fuel synthesis units will optimize scale, logistics, and economic returns, while real-time analytics ensure syngas quality, catalyst health, and fuel compliance.
Standardization, certification, and carbon accounting frameworks are equally vital. Monitoring, reporting, and verification protocols must be established for tracking the carbon intensity of synthetic fuels. Regulatory bodies such as the Bureau of Indian Standards and the Ministry of Petroleum and Natural Gas must fast-track the development of SAF and e-fuel standards to ensure market readiness.
Conclusion
India stands at a pivotal moment where appropriate R&D can catalyze the evolution of de centralized bio-refineries from conventional biogas plants. By integrating mature and emerging technologies such as SMR,
DRM, FT, methanol synthesis, and electrolytic hydrogen coupling, biogas infrastructure can be repurposed for high-value liquid fuel production. This tran sition not only supports India’s SATAT and Net Zero goals but also unlocks rural employment, industrial decarbonization, and waste valorization.
Key challenges such as TRL mismatches, integration complexity, and economic feasibility must be addressed through targeted research, pilot projects, and supportive policy. With active R&D contributions and strategic alignment of SATAT with syn thetic fuel pathways, the jour‑ ney from biogas to flight-ready fuel, green methanol, or e-die sel is not a distant dream; it is a technically achievable and eco nomically viable future. Biogas thus becomes more than a gas; it becomes the cornerstone of India’s carbon-neutral transition.
Meet the Author
Dr. Bharath G Assistant Professor, Department of Environmental Studies University of Delhi
Making of a Biogas Balloon
– From Fabric to Function
In the transition toward cleaner, renewable energy sources, biogas has gained traction as a practical and sustainable solution. Derived from the anaerobic digestion of organic waste, biogas offers energy generation with minimal environmental impact. A key component in the infrastructure of many biogas systems is the biogas balloon—a flexible structure used for gas capture and storage.
This article outlines the complete process of how biogas balloons are made, from the selection of suitable materials to
the final, functional product installed in the field. Understanding this process is essential for engineers, project developers, and environmental professionals working with biogas technologies.
1. The Role of Biogas Bal‑ loons in a Biogas Plant
Before diving into the making process, it’s important to understand what biogas balloons are and what they do.
A biogas balloon, also known as a biogas gasholder or stor
Material Science & Engg.
age balloon, is a flexible, sealed structure that stores the biogas produced from anaerobic digestion. These balloons can be mounted in different configurations:
• Digester-mounted
• Ground-mounted
• Storage balloons
Their primary purpose is to store and regulate biogas safe ly, ensuring there is no leakage, contamination, or environmental hazard.
2.
Choosing the Right Mate rial: The Fabric Matters
The effectiveness of a biogas balloon begins with selecting the right fabric. The material must withstand environmental exposure and chemical interaction with biogas, which often contains methane, carbon dioxide, hydrogen sulfide, and traces of moisture and ammonia.
Key properties required in bal loon fabric:
• Low Gas permeability: To prevent the seepage of methane, a
potent greenhouse gas.
• UV and weather resistance: For durability in outdoor installations.
• Chemical resistance: Especially to hydrogen sulfide and other corrosive components in biogas.
• Tensile strength and elastici‑ ty: To maintain structural integrity under variable pressure conditions.
• Flame retardancy: For safety against fire hazards.
European PVC-coated is a commonly used fabric due to its layer structure, durability and balance between cost and performance. These fabrics are engineered for long-term exposure, reliability, and welding performance.
3. Design and Fabric Plan ning
Once the appropriate fabric is selected, the design phase begins. Engineers use CAD (Com puter-Aided Design) software to model the balloon according to project specifications.
• Integration points for valves, sensors, and mountings.
Plotting software is used to generate flat patterns for cutting, optimizing material use while ensuring structural balance and load distribution.
4. Cutting with Precision: Au tomated Technology
Fabric panels are then cut according to the plotted designs. Precision in this stage is vital— irregular cuts can compromise the balloon’s performance and longevity.
Cutting can be done manually or through automated cutting machines equipped with software-guided controls. Automated systems offer:
• High accuracy,
• Reduced material waste,
• Improved consistency,
• Better efficiency for large-scale production.
Labelling and marking during the cutting process also help in efficient assembly later.
5. Advanced Welding Tech nology: Making Leak-Proof Joints
To convert individual panels into a continuous, leak-proof membrane, high-frequency welding & seamless welding are employed. This process uses
electromagnetic energy to fuse thermoplastic materials at the molecular level.
thermoplastic materials at the molecular level.
Advantages of high-frequency welding & Seamless welding:
•Creates strong, uniform seams,
•Ensures airtight and watertight joins,
• No need for additional adhesive,
• Long-term reliability under pressure fluctuations.
Welding requires precise alignment and strict control over temperature, pressure, and duration. Overlapping sections are carefully sealed, and the resulting seams are visually and mechanically inspected.
6. Assembly: From Panels to Structure
Once all fabric panels are cut and welded, they’re assembled
into the final balloon structure. Depending on the design (digester-top, ground-mounted, or buffer), the balloon includes:
• Gas inlet and outlet valves
• Over-pressure safety vents
• Anchoring points and mount ing belts
• Support structures for dual membranes
Each component is selected to match the chemical and pressure characteristics of biogas and is integrated carefully to ensure no weak points exist. Also, the weldable webbing-europe an accessory has a crucial role in the assembly of biogas balloons. It can be heat welded directly to the PVC-coated fabric of biogas balloons. It acts as a rein forcement layer for load-bearing points like tie-downs, lifting straps, or anchor loops.
7. Testing and Quality Con‑ trol
Before deployment, the assembled balloon undergoes a series
of quality checks to ensure safety and performance standards are met. These tests include:
• Pressure tests: The balloon is inflated to test for leaks and pressure retention.
• Visual inspection: Checks for surface defects, weak welds, or misalignments.
• Dimensional verification: Confirms shape and volume compliance with design.
• Valve functionality: Ensures smooth operation of gas control and safety features.
Testing is critical to reduce the risk of failure during operation and to validate design integrity.
8. Transportation and OnSite Installation
Biogas balloons are rolled, packed, and shipped to the site. Installation procedures vary based on the balloon type and application. Common steps include:
• Unfolding and positioning the
balloon on the prepared base or digester,
• Securing anchor points and tensioning straps,
• Connecting valves to the plant’s pipework,
• Inflating the outer membrane (in double-membrane systems),
• Calibrating sensors and monitoring systems.
Installation must be done by trained personnel to ensure alignment with technical specifications and safety standards.
9. Operational Role in a Bio gas Plant
Once installed, the balloon becomes a key operational component:
• It stores biogas produced during digestion,
• Balances supply and demand during fluctuations in gas production or usage,
• Supports pressure stabilization across the system,
• Acts as a buffer during maintenance or temporary shutdowns of other equipment.
In dual-membrane systems, the pressure between the membranes can be adjusted to maintain consistent inner gas pressure, aiding in flow control to engines, flares, or purification units.
10. Maintenance and Lon‑ gevity
With proper installation and regular maintenance, biogas balloons can operate efficiently for 8 to 12 years, depending on the material and exposure conditions.
Maintenance best practices in clude:
• Routine inspections for wear, UV damage, or material fatigue,
• Cleaning of external surfaces to prevent buildup of dirt or biofilms,
• Regular valve checks and pressure monitoring,
• Ensuring blower and air systems (for dual membranes) are functioning properly.
Any observed sagging, gas odour, or pressure drop should be investigated promptly to prevent system downtime.
Conclusion: From Fabric to Function, A Precision Engi neered Process
Biogas balloons play a vital role in the storage and regulation of renewable gas in anaerobic di-
gestion systems. Their construction, from fabric selection to on-site deployment, involves a precise and methodical process combining materials science, engineering, and quality control. Understanding the making of biogas balloons not only highlights the complexity behind what might appear to be a simple structure but also reinforces their importance in ensuring safe, efficient, and reliable biogas operations.
As the demand for renewable energy grows, so too will the importance of robust, well-designed infrastructure—starting from the fabric that holds it all together.
Meet the Author
Mr. Punit Jhaveri Director- Strategic Growth LUCKY-TECH Membranes Private Limited
