Compressed Bio Gas (CBG)

Syllabus: General Studies Paper 3

Addressing the inaugural event of Asia’s largest Compressed Bio Gas (CBG) plant in Lehragaga, Sangrur, Punjab, Union Minister of Petroleum & Natural Gas and Housing & Urban Affairs said that this plant in Sangrur is just the beginning of India’s master plan for a CBG-based rural economy.

• The Compressed Bio Gas (CBG) plant in Sangrur is a step in achieving objectives of the Sustainable Alternative Towards Affordable Transportation (SATAT) scheme, which was launched by Government of India in October 2018 to establish an ecosystem for production of Compressed Bio Gas (CBG) from various waste/ biomass sources in the country. 
• The scheme aims to empower and unleash the rural economy by supporting farmers, increase India’s domestic energy production and self-sufficiency and also reduce the air pollution, and help India lead the world toward a clean energy transition. 
• Apart from this plant, 38 CBG / Biogas Plants have been commissioned under the SATAT initiative.
• The efforts being made to encourage the indigenous manufacturing of CBG Plant equipment such as Cascades, Compressors & Dispensers.
• The scheme aims to empower and unleash the rural economy by supporting farmers, increase India’s domestic energy production and self-sufficiency and also reduce the air pollution, and help India lead the world toward a clean energy transition.

Compressed Biogas(CBG)

• It is a purified form of biogas.
• It is the mixture of hydrocarbon gases and vapours consisting mainly of Methane in gaseous form.
• It can be produced from waste including municipal solid waste, sludge from wastewater treatment plants, market residues, agricultural residues, cattle dung, sugarcane press mud among others.

Process of Producing CBG: 

CBG from biomass involves a two-pronged approach.

• First Step: Biogas is produced through the anaerobic decomposition of biomass.
• Anaerobic Process: In this process, microorganisms break down biodegradable material in the absence of oxygen. The process is used for industrial or domestic purposes to manage waste or to produce fuels.
• Second Step: Biogas contains 55 to 60% methane, 40 to 45% carbon dioxide (CO2) and trace amounts of hydrogen sulphide. The second process involves purifying the gas to remove carbon dioxide and hydrogen sulphide gases to prepare CBG.

CBG different from Compressed Natural Gas(CNG)

• Chemically, CBG is the same as CNG — both are compressed methane — and have the same calorific value.
• But, CNG is a by-product of petroleum, and CBG can be produced from any biomass, be it crop residue, cattle dung, sugarcane press mud, municipal wet waste, or effluents from a sewage treatment plant.
• Hence, this makes CBG a commercially viable option as it can be directly used to replace CNG in transportation fuel. Just like CNG, CBG too can be transported through cylinders or pipelines to retail outlets.