How Technological Intervention can Bolster Compressed Biogas/ Biomethane Plant Profitability

Energy safety and security, the barometers of development, have seen an influx in deploying and expanding into Renewable Energy space. Waste to biomethanation projects have witnessed renewed interest across the globe – Biogas generated through anaerobic digestion of biodegradable organic feedstocks i.e. municipal and industrial wastes, animal and agricultural residues, etc. have drawn interests across the developing and developed economies. Biogas contains high methane content (40–70%) that can further be upgraded (75–99% methane content), which can be injected into the National gas grid to be used as low carbon transport fuel.

Anaerobic digestion of biodegradable organic wastes provides numerous social and environmental benefits in addition to energy and manure. Biogas helps to reduce the negative externalities associated with organic wastes, such as pollution of groundwater and soil, emission of local air pollutants including dioxins and furans, and methane, a strong greenhouse gas. When compared to untreated animal dung, the nitrogen concentration of the slurry following anaerobic digestion increases, allowing it to be utilised as organic fertiliser, which would partially or completely replace the requirement for chemical fertilisers, which have a significant energy demand during manufacturing. Even though the environmental, health, and social benefits of biogas generation are well acknowledged, the CBG sector development has still some grounds to cover in India, when compared to the developments on a global scale.



If one considers developments in countries where biomethane production is being embraced on a large scale, two factors have played a major role in its development: strong policy support, and technology innovation. While the Indian Government has given a positive thrust to this market to gain significant interest from investors and entrepreneurs, it is technology innovation that will be crucial for the next phase of growth. Biogas generation is a well-established technique, but its commercial use is limited due to the necessity for on-site purification prior to shipment or usage. A thorough purification and up-gradation procedure that eliminates pollutants is required before biogas can be supplied into the National Gas Grid system or utilised as biofuel. While conventional techniques for biogas purification and upgrading remain in use, worldwide technological developers have also created cutting-edge purification and up-gradation innovations, resulting in technology that not only gives highgrade purity of methane but is also sustainable for the environment.



Investing in dependable, high-quality technology will allow making the most of the biogas generated to be converted to Bio-CNG. This will allow investors and entrepreneurs to get the most out of their CBG plant while lowering the total cost of ownership, considering the chosen biogas production or upgrading method will certainly have an impact on project expenses.

The membrane separation technique is very appealing for biogas purification because of its low energy consumption, excellent selectivity, readily designed modules, and hence lower operational costs. High methane recovery efficiency (>95%) can be achieved, while pure CO2 can be produced as a by-product for various industrial purposes, therefore enhancing the business. The biogas can be upgraded to the chosen methane concentration depending on the grid or user needs. Evonik’s newest Membrane technology, marketed as “SEPURAN® Green,” employs highly selective polymer membranes to convert raw biogas into extremely pure CBG in a simple and economical manner (biomethane). With more than 600 references worldwide, SEPURAN® Green membrane technology has the highest CO2/CH4 selectivity and is, therefore, a superior technology for upgrading biogas.

Deploying membrane technologies also have advantages for CBG project investors on profitability and sustainability - traditional technologies need comparatively large amounts of energy as well as auxiliary materials and chemicals, resulting in wastes and wastewater generation that must be treated and disposed of. Also, methane loss during the extraction and up-gradation process via Membrane technology is much lower than the methane loss value of several other biogas purification methods. Membrane technology hence is the ground-breaking method of biogas separation and purification for deploying the benefits of waste to biomethanation projects.

The nation has huge promise in the area of biomethanation projects, considering the country has huge biomass and organic wastes – potential waiting to be unlocked. According to research published in Science Direct, it is envisaged that Biogas will emerge as a promising fuel in the next two decades in India - 310 to 655 billion m3/year in the year 2040, owing to rising waste generation and adequate disposition of relevant infrastructure for waste collection efficiency.

Since 1982, India, among other countries, has promoted ‘Waste-to-Energy’ projects. CBG has lately emerged as an important component of India’s future green mix, as described in the Government of India’s 2018 Sustainable Alternative towards Affordable Transportation (SATAT) programme. The Indian government, under the SATAT scheme, envisages setting up 5,000 CBG plants by 2023- 24 with a production target of 15 MMT. Biogas produced from different waste and biomass sources in the country has several benefits, including reduced natural gas imports, reduced GHG emissions, reduced burning of agricultural residues, remunerative income to farmers, job creation, better waste management, and so on. The SATAT project is consistent with the objectives of the ‘AatmaNirbhar Bharat’, ‘Swachh Bharat Mission,’ and the national precedence to boost the MSME sector. Conclusion While cost plays a key role in shortlisting technology for biogas purification, it is important to remain cognisant of the long-term implications of using technologies that are not friendly to the environment. After all, CBG is intended to be a green and sustainable fuel source that will only be so if the processing that goes into its production remains eco-friendly as well.
 

- Mohan NS, CEO, SLPP RENEW
  Praveen Badiger, COO, SLPP RENEW