4 Methods of Capturing CO2 From Fermentation

Capturing CO2 from fermentation can be achieved through various methods. One approach is to use absorption technology, where a solvent is used to absorb the CO2 released during fermentation. Another method involves using membranes that selectively allow CO2 to pass through, capturing it in the process. 

In a world grappling with the urgent need to reduce greenhouse gas emissions, the search for innovative solutions has become paramount. One such groundbreaking technique gaining attention is the capture of carbon dioxide (CO2) from fermentation processes. 

Fermentation, a widely used method in industries such as brewing, biofuel production, and food processing, releases significant amounts of CO2 into the atmosphere. However, by implementing CO2 capture technologies, we can transform this waste product into a valuable resource. Not only does capturing CO2 from fermentation help mitigate climate change by reducing emissions, but it also presents exciting opportunities for carbon utilization and storage. 

Join us as we delve into the fascinating realm of CO2 capture from fermentation, exploring its environmental benefits, technological advancements, and its potential to revolutionize sustainable practices across various industries. 

The Role Of CO2 In Fermentation Processes

Carbon Dioxide (CO2) is a byproduct of fermentation, and its role cannot be overstated. It is responsible for the bubbles in your champagne, the rise of your bread dough, and the tangy flavor of your sauerkraut. Without CO2, fermentation as we know it would not be possible.

In the world of wine and beer production, CO2 plays a vital role in creating the effervescence that we all love. During fermentation, yeast consumes sugar and converts it into alcohol and CO2. The CO2 gets trapped in the liquid, creating those delightful bubbles that tickle our taste buds. In fact, the amount of CO2 produced during fermentation can determine the level of carbonation in a beverage. Winemakers and brewers carefully control this process to achieve the desired level of fizziness.

In baking, CO2 is equally important. When yeast is added to the dough, it ferments and releases CO2 gas. This gas gets trapped in the dough’s gluten network, causing it to rise and become light and fluffy. The CO2 also contributes to the distinctive flavor and texture of baked goods.

But CO2 is not only present in alcoholic beverages and bread. It also plays a role in the production of other fermented foods like yogurt, pickles, and cheese. In these processes, bacteria consume sugars and produce lactic acid and CO2 as byproducts. The lactic acid gives these foods their tangy taste, while the CO2 adds a bit of fizziness.

One thing all these fermentation processes have is the byproduct of CO2, so what can you do with this colorless odorless gas?

Benefits Of Reusing CO2 From Fermentation

Capturing and reusing CO2 from fermentation has gained attention due to its potential environmental and economic advantages. By repurposing this gas, industries can significantly reduce their carbon footprint and reliance on fossil-fuel-derived CO2 sources. Additionally, reusing fermentation CO2 can lead to cost savings by eliminating the need to purchase CO2 from external suppliers. Below we explore the various methods used to capture CO2 during fermentation and the innovative ways in which it can be reused.

Methods Of Capturing CO2 During Fermentation

Several techniques are employed for capturing CO2 released during fermentation. These methods can be broadly categorized as absorption, adsorption, membrane separation, and cryogenic separation. Each technique has its unique advantages and applications, allowing industries to select the most suitable method based on their specific requirements.

Absorption

Absorption involves the use of solid absorbent materials or a liquid to capture CO2 from the gas mixture. Substances like sodium hydroxide (NaOH) or monoethanolamine (MEA) are commonly used. The CO2 is absorbed into the material, and then through heating, the CO2 gas is released and collected for reuse.

Adsorption

Adsorption relies on solid adsorbent materials, such as zeolites or activated charcoal (activated carbon), to capture CO2. These materials have a high affinity for CO2, allowing them to adsorb the gas while allowing other gases to pass through. The captured CO2 is released by increasing the temperature or decreasing the pressure, making it available for reuse.

Membrane Separation

Membrane separation utilizes specialized membranes that selectively allow CO2 to pass through while retaining other gases. The gas mixture is transferred through the membrane, allowing CO2 to permeate through the membrane, separating it from the other gases. This method is particularly useful when a high purity of CO2 is required for specific applications.

Cryogenic Separation

The process of cryogenic separation entails lowering the temperature of the gas mixture to extremely low levels, resulting in the condensation of CO2, with the remaining gases staying in a gaseous state. 

The separated CO2 can then be collected and stored for future use. This method is commonly used when high-purity CO2 is required.

The Process Of Reusing Captured CO2 From Fermentation

Once the CO2 is captured during fermentation, it can be repurposed for various applications. One of the primary uses of recaptured CO2 is as an inert gas for filling the headspace in tanks during storage and transportation. By replacing oxygen with CO2, the risk of oxidation and spoilage is minimized, ensuring the quality and longevity of the product.

Additionally, recaptured CO2 can be used in carbonation processes, such as in the production of sparkling wines and carbonated beverages. The reuse of fermentation CO2 reduces the reliance on external sources of carbonation and provides a sustainable alternative.

Implementing CO2 Capture And Reuse

One notable example of successful CO2 capture and reuse comes from Familia Torres, a renowned wine group in Spain. They have developed an innovative system to capture and reuse CO2 produced during fermentation, significantly reducing their environmental impact.

The system involves collecting the CO2 released during winemaking in inflatable balloons positioned above the fermentation tanks. The gas is then compressed and stored in a pressure tank for later use. When needed, the captured CO2 is mixed with nitrogen or used as an oxidation-preventing protective gas during processes like tank filling.

Familia Torres estimates that they can reuse approximately 20 tonnes of emission-neutral CO2 per year, accounting for one-third of the gas required by their winery. This technology not only reduces their carbon footprint but also offers cost savings by eliminating the need to purchase fossil-fuel-derived CO2.

The Future Of CO2 Capture And Reuse In Fermentation

As industries become increasingly aware of the environmental impact of their operations, the adoption of CO2 capture and reuse technologies in fermentation is expected to grow. The development of more efficient and cost-effective methods will likely make these practices more accessible to a wider range of businesses.

By capturing and reusing CO2 from fermentation, industries can reduce their reliance on fossil-fuel-derived CO2 sources and contribute to a more sustainable future. The benefits extend beyond environmental considerations, as cost savings and improved product quality are also significant advantages.

How To Measure CO2 During Fermentation?

It is important to measure the levels of CO2 to ensure that the fermentation is proceeding as expected and it allows you to measure how much CO2 you are capturing and reusing. One effective way to measure CO2 during fermentation processes is by using a CO2 meter/sensor.

A CO2 meter is a device that is specifically designed to measure carbon dioxide levels in the air. It works by using a sensor to detect the presence of CO2 and then displays the concentration in parts per million (ppm) on a digital screen. 

To measure CO2 during fermentation, place the CO2 meter near the fermentation vessel, ensuring it is near to where the CO2 is released. The meter will then start detecting and measuring the CO2 levels in real-time. Measuring CO2 allows you to monitor the progress of the fermentation and make any necessary adjustments to temperature, yeast activity, or other variables.

Using a CO2 meter provides several advantages when measuring CO2 during fermentation. First, it provides accurate and precise measurements, allowing you to have a better understanding of how the fermentation is progressing. This information can be crucial in ensuring the quality and consistency of your final product.

Additionally, using a CO2 meter allows you to track the levels of carbon dioxide throughout the entire fermentation process. This can help you identify any potential issues or anomalies that may arise, such as stalled fermentations or excessive CO2 production. By monitoring these levels, you can take timely action to rectify any problems and ensure a successful fermentation.

Summary

Capturing and reusing CO2 from fermentation offers a promising solution for reducing greenhouse gas emissions and promoting sustainability in various industries. With ongoing advancements in technology and the adoption of innovative practices, the role of CO2 in fermentation is evolving from a by-product to a valuable resource that can benefit both the environment and the bottom line.

By implementing these practices, businesses can contribute to a more sustainable future while maintaining the quality and integrity of their products.

If you have any questions regarding fermentation, or which CO2 meter will best suit your testing needs, do not hesitate to contact the world-class team at Atlas Scientific.

CO2 Sensor & Scrubber