UNDERSTANDING THE BIOGAS CHILLING AND DEHYDRATION PROCESS
Biogas is a useful alternative energy source derived from transforming organic landfill materials, digester substances, and wastewater. Before this gas can be efficiently utilized, it must be dehydrated. Gas drying is a critical final step in optimizing biogas as a fuel source and significantly improving its usefulness in diverse applications.
How Moisture Affects Biogas
As mentioned earlier, newly synthesized biogas contains significant amounts of moisture, making it unsuitable for immediate use. The higher the moisture content, the lower the calorific or heating value.
In other to improve the heating characteristics, biogas should be subjected to a dehydration process that will reduce its water vapor levels. In the rest of this article, we will consider how this dehydration process works and the benefits associated with an effective moisture elimination strategy.
What Other Contaminants Can Be Found in Biogas?
Apart from having a high moisture content, unrefined biogas is often found to possess high proportions of hydrogen sulfide. This is particularly true for biogas sourced from animal wastes, including dairy and swine manure. Hydrogen sulfide is a highly poisonous gas that limits the ability of biogas processing plants to synthesize useful biomethane.
The hydrogen sulfide elimination process for biogas can be achieved by carefully oxygenating the biogas transport channels limiting the amount of hydrogen sulfide that flows downstream. This additional process step is instrumental in protecting equipment such as valves, pipelines, and collection vessels from gas-related damage.
Biogas Drying and Cooling Process
The biogas dehydration process requires specialized heat exchanger and chiller systems to properly eliminate excess moisture. Several configurations for gas drying systems are used with biogas; however, the underlying process is similar.
To begin with, saturated biogas recovered from landfills and digester plants is redirected into a cooling plant that integrates a heat exchanger and/or a chiller unit. The temperature of the biogas is reduced significantly by conducting it through a heat exchanger that pulls heat away from the gas. Cooling within the dehydration system is facilitated by a chiller system connected to the heat exchanger.
The most used industrial chiller variants are air-cooled or water-cooled models. The chiller unit attached to the drying plant will decrease the temperature of the biogas conducted through it to very low levels resulting in moisture condensation. The water vapor precipitant will condense out of the biogas and drop into collecting tanks. Meanwhile, the dried biogas flows through into separate storage vessels or directly to applications requiring its use.
Benefits of Drying and Chilling Biogas
The benefits of drying biogas include the following:
- Improved calorific value due to lower moisture content.
- Greater fuel efficiency as dried biogas will achieve more effective heating than saturated biogas.
- Reduced likelihood of moisture-associated damage to biogas-powered engines.
- Compliance with minimum permitted moisture levels for transport via industrial pipelines.
Explore Cold Shot’s Biogas Chillers
At Cold Shot Chillers, we manufacture state-of-the-art biogas chillers in various configurations targeted at diverse industrial applications. We offer both portable and larger-sized chillers depending on your intended application.
Why Choose Cold Shot Biogas Chillers?
Biogas dehydration is a crucial step in the synthesis of top-quality biomethane, and our air-cooled and water-cooled chillers are well-suited to the task of properly drying the gas. In addition, our services include the installation and maintenance of water-cooled heat exchangers powered by our custom chillers.
Highlighted below are some benefits of choosing Cold Shot Chillers.
- Design customization to suit your required specifications.
- Our chiller units provide you with cost-effective options. Our cooling systems are priced competitively to give the best value for your budget.
- We have a great, welcoming, and highly experienced team available around the clock to provide all the information you need when selecting your process chiller.
- We also offer a same-day quote for all your inquiries. You can get a quote for your application within 30 minutes of contacting us as we prioritize the value of your time.
To learn more about our products and services, please contact us today!