Renewable Diesel Process Snapshot

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1. Feedstock

Diamond Green Diesel receives animal fat and used cooking oil primarily from restaurants, supermarkets and other foodservice establishments and inedible corn oil primarily from ethanol plants. Feedstocks can enter the plant through rail, truck or ships and barges. 


2. Processing

The feedstocks are treated to remove impurities and then they are hydro treated with high-pressure hydrogen to remove oxygen and separate the water. The next step is isomerization where cold flow properties are managed to ensure compatibility with existing infrastructure and engines. The final step is fractionation, the separation into finished products.


3. Distribution

Renewable diesel is stored until it is shipped to our customers primarily in low-carbon markets such as California, Canada and Europe. It can be transported via pipeline, ship or railcar.

What is Diamond Green Diesel?

Take a look at what Valero is doing to advance the future of energy with low-carbon fuels, specifically at Diamond Green Diesel.


The Science of Renewable Diesel

  • What is Renewable Diesel?

    Renewable diesel is a true hydrocarbon, like ultra-low sulfur diesel, gasoline, or crude oil, and can be used anywhere those fuels can be used without modifications to the engines or pipelines. 

    Renewable diesel has an energy density value equivalent to ultra-low sulfur diesel (ULSD), which is a cleaner-burning, lower-emission fuel than regular diesel.

    Our low-carbon renewable diesel reduces the life cycle greenhouse gas emissions up to 80%, compared with traditional diesel.

  • How is Renewable Diesel Made?

    The used cooking oil and inedible corn oil are treated to remove impurities. 

    • Hydrotreating: Using high pressure hydrogen to remove the oxygen (which is converted to water).
    • Isomerization: A chemical process that changes the structure of the molecules without changing the number of atoms. This enables the fuel to be used in cold weather.
    • Fractionation: A chemical process to separate the liquid into finished products.
  • What Products are Used to Make Renewable Diesel?

    Fat is collected from supermarkets, butchers, meat processors and other foodservice establishments.

    Used cooking oil from restaurants, supermarkets and other food service establishments and inedible corn oil from ethanol plants.

  • How is Renewable Diesel Distributed?

    Renewable diesel can be distributed using the established petroleum logistics system.

Diamond Green Diesel Employees performing safety test

Diamond Green Diesel (DGD)

Learn about our joint venture to supply renewable diesel to low-carbon markets.