Greenleaf Sets the Bar for Safe, Efficient Biodiesel Production
Greenleaf Biofuels recently began producing biodiesel fuel at its New Haven, Connecticut plant. When fully operational the facility is slated to produce up to 10 million gallons of biodiesel fuel per year.
Biodiesel can be produced from a large number of organic terrestrial and aquatic materials including vegetable and algal oils, as well as commercial and industrial wastes, such as waste vegetable oil, animal fat, and/or recycled cooking grease.
After considerable investigation, Greenleaf Biofuels chose to construct its cost-effective, moderate sized biofuel production plant within the fuel storage tank farm of New Haven Harbor, thereby providing easy access to truck, rail, barge and deep-water vessel delivery points. And even though Greenleaf intends to use trucked-in waste vegetable oils collected from restaurants and food manufacturers along the Boston to New York City corridor, the New Haven Harbor location provides Greenleaf the option to use a wide array of feedstock delivery methods.
Bioenergy is renewable energy made from any organic material from plants or animals. Sources of bioenergy are called “biomass,” and include agricultural residues, municipal solid wastes, industrial wastes, and crops grown solely for energy purposes.
Biomass is an attractive petroleum alternative because it is a renewable resource that is more evenly distributed over the Earth's surface than finite energy sources, and it may be exploited using more environmentally friendly technologies.
Today, biomass resources are used to generate power and to produce liquid transportation fuels, such as ethanol and biodiesel. Ethanol is the most widely used liquid transportation fuel, or biofuel. A majority of ethanol is made from corn, but new technologies are being developed to make ethanol from a wide range of renewable agricultural and forestry resources. Continue reading
The New Haven Harbor also strategically places Greenleaf’s biodiesel product at a key home heating oil distribution hub that annually delivers about 400 million gallons of home heating oil to local businesses and residents.
The Biodiesel Process
A growing number of batch- and continuous-feed technology alternatives are available for producing biodiesel. Acid esterification and base transesterification are among the more popular, mainly because they can handle a wide variety of feedstocks ranging from used oils and animal fats to virgin oils. Greenleaf Biofuels evaluated various methods and chose a fully continuous-feed biodiesel production technology developed by JatroDiesel.
JatroDiesel’s process begins by drying the feedstock. Next, acid esterification takes place, using methanol and sulfuric acid to convert free fatty acids into methyl ester. The methyl ester is passed through a dual-stage transesterification process, which converts triglycerides into biodiesel and glycerin. The glycerin and excess methanol are removed from the biodiesel, purified and cycled back for reuse in the process.
The biodiesel is polished using magnesium silicate-based compounds to eliminate any trace amounts of glycerin (soap) and then passes through a final filter on its way to finished product storage.
Compliance Is Just the First Step
Locating the process in the New Haven harbor area allows Greenleaf Biofuels to strategically leverage myriad distribution and transportation options, but it also imparts significant responsibilities. Following local, state and federal regulations, Greenleaf has implemented:
- A high-capacity, water-deluge building sprinkler system designed to protect the entire processing area.
- A building ventilation system designed to draw fresh-air across the entire processing area.
- A foam fire suppression system designed to protect the methanol truck unloading and tank-farm area.
- A hardwired safety-instrumented-system.
- Electrical and electronic devices suitable for use in hazardous areas.
Additional process protection measures include ongoing operator training and a robust process control system designed to assist operators in maintaining the safe and efficient production of biodiesel.
To ensure Greenleaf operators have accurate, timely process information presented in easy to interpret, easy to use graphical displays, Emerson Process Management DeltaV operator stations were implemented using human-centered design (HCD) practices, and standardized dynamos embedded in the DeltaV digital automation system. Rooted in military and international standards, HCD graphic displays use: