Overcoming the 4 biggest challenges facing biodiesel producers

By Julie Valentine, Director, Refining Flow Solutions, Emerson Automation Solutions, special to The Digest

More and more countries are seeking greener energy and solutions to meet stricter environmental standards, and biofuels are emerging as a go-to energy source. As demand increases, so too do the challenges for energy producers, including diversity of feedstocks, reliability of equipment, ever-changing regulatory standards and low-carbon outputs.

Automation technologies, software and analytics are vital tools to navigate these challenges – yet the industry is just beginning to tap into their potential. When used the right way, they can help jump-start the renewable energy industry while laying the groundwork for long-term sustainability.

Feedstock flexibility: What do yak fat, cooking oil and agricultural waste have in common?

Biodiesel production typically requires a more expensive buy-in due to a number of factors, starting with the extreme differences in feedstock sources – chicken fats, soybean oil, corn oil, forest residue and more. This kind of feedstock variability, all of which have different fluid properties associated with them, poses challenges to the way facilities determine everything from fluid dynamics to maintenance to production forecasting.

These dynamics make it essential for producers to rely on advanced automation technologies and industry knowledge to design, build and operate their biorefineries with the flexibility and adaptability diverse feedstocks demand. Automation technologies help optimize operations under varying feedstocks to improve pretreatment, increase yields and reduce equipment damage downstream. Advanced instrumentation and smart metering allow renewable diesel facilities to measure yield more accurately, either through the use of Coriolis meters and radar technology to measure fluids that are independent of the feedstock properties or onboard diagnostics that help verify instrument health.

In a similar vein, software analytics technology identifies optimal and sub-optimal operating conditions for each feed type, enabling better control of the reactions and maximizing diesel yield (not over-cracking), while also improving the safety of the plant by keeping reactors within the operational limits.

Some of the world’s largest producers of renewable diesel and sustainable aviation fuel produced from renewable waste implement software and technology to digitally automate and optimize production. Singapore-based Neste, for example, expanded its refinery to have additional capacity to produce up to 1 million tons of sustainable aviation fuel and renewable raw materials for polymers and chemicals, which supports the company’s goal to reduce customers’ greenhouse gas emissions by at least 20 million tons annually by 2030.

Equipment reliability: Monitoring assets and preventing corrosion

One of the ways biorefineries can lower their carbon footprint is by operating their processes more efficiently, minimizing downtime and actively monitoring equipment performance.

An example of this is utilizing wireless, ultrasonic sensors that can continuously monitor the thickness in pipes and in vessels. This enables personnel to accurately assess what parts of the process may be experiencing corrosion or require inspection before they fail.

The same sensors can also collect corrosion data that is analyzed, interpreted and visualized into actionable reports. Key to these sensor software solutions are predictive algorithms that interpret operational data to anticipate maintenance needs.

Innovations like these add up to increased uptime, reduced costs for the replacement of specialty components, a safer work environment, and reduced chance of potential accidents like a loss of containment.

Play by the rules: Meeting regulatory standards

Biofuel production can be a more complicated process than its fossil fuel-based equivalent, which leads the regulatory framework surrounding the industry is becoming increasingly complex. Depending on the country, companies face different regulations on everything from taxes to government incentives. In order to meet these extensive reporting requirements, renewable diesel plants need to gather and integrate data from many sources including the fuels pathway, modes of transportation of feedstocks and products, energy usage, contracts and invoices.

Operators can collect, host and validate this information through automated data lakes, which leverage software to automate the data gathering, provide visualization tools and distribute reports in the format needed to meet regulatory requirements. The flexibility of this automated software is key to the process as well since regulatory reporting requirements are continually changing. The data management platform ultimately helps reduce costs associated with data collection, but also makes all the data auditable moving forward as standards change.

From well to wheel: Sustainability solutions and metrics

The last major challenge renewable diesel producers face is delivering a low-carbon product at all stages of the lifecycle of the product.  As sustainability standards increasingly incorporate scope 1, 2 & 3 emissions, biorefineries must be more mindful of everything from how they source feedstocks, produce the fuels, transport their product, and finally to its end use as a transportation fuel.

To help support tracking of emissions during the production phase, continuous and predictive emissions monitoring technology can be integrated into combustion operations to monitor and optimize those processes.  Gaining a better understanding of emissions generated during various operational modes and scenarios will help to evaluate and optimize operations.

Another technology which supports the monitoring and reduction of emissions are wireless acoustic transmitters, which work in conjunction with pressure relief valves. These transmitters can locate the source, time, and duration of PRV leaks or releases, providing important environmental and safety data that can help reduce overall emissions. Performing a compositional analysis using an on-line gas chromatograph can detail what components went to the flare to be released.

When combined correctly, these automated and advanced diagnostics ease the overall burden on the operator, while also enabling more efficient problem solving and improved overall control.

It’s also important to measure the carbon intensity of the fuel – its lifecycle from well to wheel that is impacted by type of feedstock, distance from the feedstock source to processing, the efficiency of the energy used in production, and emissions. Renewable diesel plants are large consumers of energy and hydrogen with complicated process interactions, so energy management systems with AI-based analytics are critical to minimize energy use. Instead of relying on monthly energy reports, operators can monitor energy usage in real-time. Emerson data shows plants that implement energy management systems see a 5-10% reduction of site energy usage, which greatly improves a refinery’s carbon intensity score.

There might not be one well-to-wheel path for all renewable fuels, and the feedstocks run the gamut from corn oil, yak fat or yard waste, but one thing is for certain: existing digital technologies can help producers build in flexibility and system integrity to meet changing requirements and demand.