Effectively managing organic waste has become an environmental and economic imperative in today’s world. Among the emerging technologies, biomethanation stands out as a promising solution. This biological process transforms organic materials into biogas and digestate, in the absence of oxygen, through the action of specific microorganisms. In this article, we will explore in detail what biomethanation is, how it works, and how it compares favorably to composting. We’ll focus especially on the treatment of two specific types of waste: coffee grounds and organic liquids such as expired beer or soft drinks. We’ll also address the significant environmental benefits, particularly the reduction of CO₂ emissions, for companies choosing biomethanation over conventional disposal methods like sewer dumping or field spreading.
The Principle of Biomethanation
Biomethanation, also known as anaerobic digestion, is a biological process that breaks down organic matter in the absence of oxygen. It is carried out by a complex community of microorganisms that convert this matter into biogas — primarily composed of methane (CH₄) and carbon dioxide (CO₂) — as well as into digestate, a nutrient-rich residue.
Process stages:
- Hydrolysis: Complex organic compounds are broken down into simpler substances.
- Acidogenesis: The products of hydrolysis are transformed into organic acids.
- Acetogenesis: Acids are converted into acetate, CO₂, and hydrogen.
- Methanogenesis: Methane is produced from acetate or from CO₂ and hydrogen.
Compared to composting, biomethanation has several advantages. First, it is faster and can be carried out in a controlled, closed environment, minimizing odors and nutrient loss. Second, it produces biogas — a renewable energy source — whereas composting only produces compost. Finally, the digestate from biomethanation often contains more bioavailable nutrients than traditional compost.
Specific Waste Treatment
Coffee Grounds
Coffee grounds are a common waste product in the coffee industry, often thrown away or used in small amounts as a soil amendment. Because of their richness in organic compounds, coffee grounds offer a valuable opportunity for biomethanation. This approach not only reduces waste volume but also transforms this by-product into valuable energy resources.
Benefits of biomethanating coffee grounds:
- Significant waste volume reduction: The grounds are compacted and transformed, lowering their original volume and associated transportation and disposal costs.
- Biogas production: The process recovers energy in the form of biogas, which can be used to generate electricity, heat buildings, or be refined and injected into the natural gas grid.
- Digestate as fertilizer: The residual digestate can be used as an organic fertilizer, rich in essential nutrients for plants.
Application example: Some coffee companies and waste treatment facilities have begun using biomethanation to manage their coffee grounds, seeing it as a path to greater sustainability and reduced ecological footprint.
Organic Liquids
Organic liquids such as expired beer, soft drinks, and other food-grade liquid waste often present a disposal challenge due to their volume and polluting potential. Biomethanation offers an efficient way to valorize them while protecting the environment.
Specific process:
- Pretreatment: Liquids often need to be diluted or have their pH adjusted before entering digesters to optimize microbial activity.
- Emissions management: Gas emissions must be properly managed, especially with volatile substrates like alcoholic beverages.
Benefits of biomethanating organic liquids:
- Waste valorization: Turns an environmental liability into an energy asset.
- Greenhouse gas emission reduction: Prevents uncontrolled anaerobic decomposition in the environment, which would release methane — a potent greenhouse gas.
Environmental and Economic Benefits
Biomethanation not only offers a waste management solution but also contributes to environmental protection and improves the profitability of companies that adopt it. These benefits include reduced CO₂ emissions, lower waste treatment costs, and the production of renewable energy.
CO₂ Emission Reduction
A key environmental benefit of biomethanation is its significant reduction in greenhouse gas emissions, particularly CO₂ and methane. Traditional disposal methods like incineration or landfilling emit large amounts of these gases. In contrast, biomethanation captures them and converts them into usable biogas. The captured methane can be burned to generate energy, emitting CO₂ — but on a much smaller scale and within a shorter, controlled carbon cycle.
Business Savings
Companies using biomethanation to treat their waste can achieve substantial savings:
- Lower waste management costs: Less waste to transport and treat by costly methods like incineration or landfilling.
- Energy production: The biogas generated can be used to power the company’s operations or sold as an energy source, creating a new revenue stream.
- Use of digestate: The digestate can be used or sold as fertilizer, reducing the need for chemical fertilizers and offering an eco-friendly alternative.
Impact on Corporate Social Responsibility
Adopting biomethanation can also enhance a company’s brand image by demonstrating a commitment to sustainable development. This can strengthen customer and stakeholder loyalty and open doors to grants and government incentives for sustainable practices.
2M Resources and Biomethanation: An Eco-Responsible Solution for Expired Liquid Food Waste
For over five years, 2M Resources has established itself as a sustainability leader in Quebec for processing and recovering expired liquid food products. Committed to circular economy principles, this Quebec-based company is known for its innovative, environmentally conscious approach to organic waste management.
In 2023 alone, over 8,000 metric tons of liquid were sent for biomethanation — equivalent to more than three Olympic swimming pools!
2M Resources’ Environmental Commitment
2M Resources provides a turnkey service for destroying liquid food products, ensuring that every aspect of the waste — from the container to the contents — is valorized. This process not only handles the waste efficiently but also transforms it into valuable resources for energy and agriculture.
Valorization Process
Treatment begins with collecting expired products, which are then crushed and blended into a uniform material. This preparation is key for optimizing the anaerobic decomposition that follows. The organic matter is treated by microorganisms in an oxygen-free environment, where it is converted into methane-rich biogas and digestate — a nutrient-dense organic fertilizer.
The biogas is then refined to remove CO₂ and impurities, becoming biomethane. This biomethane can be injected into the natural gas grid or used to produce electricity and heat — or even as vehicle fuel.
Benefits for 2M Resources’ Clients
Clients of 2M Resources benefit from responsible waste management while contributing to sustainable development efforts that protect the environment and water resources. By choosing 2M Resources, companies can meet their ESG (Environmental, Social, and Governance) goals and stand out through forward-thinking, eco-responsible waste management.
2M Resources’ Role in the Circular Economy
Founded in 1999, 2M Resources has developed recognized expertise in glass and material recycling. As a leader in Eastern North America, the company plays a vital role in Quebec’s circular economy value chain. 2M’s approach — combining high-quality glass recycling with organic waste valorization through biomethanation — demonstrates its leadership in developing sustainable, innovative solutions.
By integrating processes like biomethanation, 2M Resources not only creates value for its clients and the environment but also redefines industry standards by promoting practices that move the sector toward a more sustainable future. Through these initiatives, 2M shows that circular economy principles and environmental responsibility can go hand in hand with commercial success and industrial innovation.
