TODAYS BOILER | NOVEMBER 2023
How to Lower Your Boiler’s Carbon Footprint with Sustainable B100 Biodiesel
Key design and regulatory considerations when transitioning industrial boiler systems from running on fossil fuels to pure biodiesel.
FIGURE 1. B100 offers a number of benefits compared to more dilute biodiesel blends. Images courtesy of Emerson
The environmental risks associated with carbon emissions have escalated over the last several decades. While modern technologies, such as industrial burner and boiler systems, have enhanced our standard of living, they have contributed to these rising emissions. According to the U.S. Environmental Protection Agency (EPA), burning fossil fuels for commercial and residential heating accounted for 13% of U.S. greenhouse gas emissions in 2020, with the total amount of emissions across all economic sectors totaling 5,981 million metric tons of carbon dioxide.
One of the ways we can effectively reduce these risks is by modifying the fuels we use within heating applications, converting legacy fuel trains from running on petroleum and other fossil fuels to clean, renewable, and biodegradable biofuels. Unlike fossil fuels, which slowly form naturally from dead plant and animal remains, biofuels are produced over a short period of time from plant-based biomass.
One major type of biofuel is biodiesel, which is derived from vegetable oils; animal fats; and nonedible raw materials, such as the frying oils in fast-food restaurants. It can be used as a drop-in; stand-alone fuel; or blended with conventional fuels, like petroleum, to power diesel engines and distribution infrastructure. One type of biodiesel that is gaining ground in the industry is B100. This fuel source, which is 100% pure biodiesel, offers a number of benefits compared to more diluted biodiesel blends.
Yet, while biodiesel — particularly B100 — is an excellent carbon-neutral fuel upgrade for legacy combustion systems, there are still regulatory considerations to keep in mind when working with these fuel sources. Let’s explore some of these considerations and their impact on your choice of combustion components, ensuring you minimize your burner’s carbon footprint as much as possible.
What is Biodiesel and B100?
Whereas traditional diesel fuel is derived from petroleum, biodiesel is made from a variety of renewable feedstocks, such as vegetable oils and animal fats. It is produced through a process called transesterification, during which the feedstock chemically reacts with an alcohol and a catalyst to produce biodiesel and glycerin.
The resulting biodiesel can be blended with conventional diesel fuel (petrodiesel) in different proportions to create biodiesel blends. For example, the B20 blend contains 20% biodiesel and 80% petrodiesel. Unlike B20 and other blends, B100 is 100% pure biodiesel.
So what makes this pure blend so advantageous? For one, it can be used in industrial boilers and burners designed to use petrodiesel — no modifications are necessary. B100 also has a higher cetane number than petrodiesel, meaning it burns more cleanly and efficiently. By reducing the buildup of deposits in the fuel system compared to petrodiesel, B100 even helps to extend the service life of combustion equipment. Additional benefits of B100 include the following:
- B100’s flash point is 130°-150°F, which is higher than petrodiesel’s flash point (125°). As a result, B100 is less likely to ignite accidentally; and
- Because B100 has a higher lubricity than petrodiesel, it can protect the fuel system from wear and tear.
Emerging B100 Regulatory Requirements
Given biodiesel’s potential to significantly lower emissions, the Intergovernmental Panel on Climate Change (IPPC) released guidelines for governments and industries to invest in biodiesel as a fuel source for industrial burners and boilers. The U.S. government, for example, tasked the EPA with creating biodiesel targets that align with IPCC guidelines. Early adopters of these targets include New York, Rhode Island, and Connecticut.
In response to the EPA’s biodiesel targets, major standards organizations, like the American Standards for Testing (ASTM) and Underwriters’ Laboratories (UL), have already created and released regulatory requirements for biodiesel, including the use of B100. For example, the ASTM D6751 specification covers B100 in Grades S15 and S500 for use as a blend component with middle distillate fuels, while the UL 428B standard can certify fuel oil safety shut-off valves for B100.
Implementing the Right Components
By upgrading boiler fuel trains to support B100 biodiesel, it’s possible to reduce emissions by as much as 50%, moving you closer to net-zero targets and avoiding costly state penalties for emissions levels. To ensure compliance, it’s important to work with boiler manufacturers that use components — including the valves on the fuel and pilot lines — that meet B100 standards.
Examples of components that are certified for B100 standards include ASCO™ Series 262 and 263 two-way solenoid valves. Valves like these make it possible to transition to a more sustainable energy source while simplifying compliance with evolving regulations. As part of their compliant design, these valves feature elastomers that have been tested to ensure their long-term chemical compatibility with corrosive biodiesel. Compared to the required testing for biodiesel blends, like B20, B100 requires a more rigorous evaluation of elastomer resistance and performance in order to ensure the materials can withstand the more chemically aggressive nature of pure biodiesel.
To learn more about how to optimize your industrial burner application, whether to reduce emissions, maximize efficiency or improve productivity, visit www.emerson.com/combustion.
By Yussef Abou-Ghanem, product marketing manager of combustion, Americas, Emerson
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