ARB staff posts five more LCFS fuel pathways: biodiesel, RD, ethanol
21 February 2014
California Air Resources Board (ARB) staff has posted five new Low Carbon Fuel Standard (LCFS) fuel pathway applications to the LCFS public comments website: two for biodiesel, one for renewable diesel, and two for ethanol.
The baseline CI value for gasoline is 95.86 g CO2e/MJ; for diesel fuel, it is 94.71 g CO2e/MJ.
Biodiesel. Methes Energies Canada produces biodiesel from Used Cooking Oil (UCO) and Corn Oil (CO) in a biodiesel plant in Sombra, Ontario, Canada. The plant uses a standard FAME transesterification process to produce biodiesel and has a production capacity of 13.5 million gallons per year. The corn oil that Methes obtains is from a dry mill ethanol plant that dries all of its DGS.
Methes calculates that the total carbon intensity (gCO2e/MJ), including land use or other indirect effects, for the biodiesel produced from UCO is 19.75. The carbon intensity (CI) for biodiesel from CO is 9.78.
Renewable diesel. Neste Oil Singapore Pte Ltd. produces non-ester renewable diesel (RD) from multiple feedstocks at its plant in Singapore. The plant produces approximately 250 million gallons of RD annually; the product is marketed under the NExBTL trademark.
Neste has applied for a Low Carbon Fuel Standard (LCFS) pathway covering the RD produced from tallow obtained in New Zealand. (Neste has also applied for a pathway for RD produced from Australian tallow, earlier post.)This feedstock is rendered in New Zealand and shipped by ocean tanker an estimated 5,780 nautical miles to the Neste plant. The energy consumption data for the rendering process was taken from eight existing rendering plants that currently supply Neste. The carbon intensity of the tallow rendering phase of this pathway was estimated using the average energy consumption from these eight plants. Once the rendered tallow has been converted to renewable diesel, the finished fuel is transported an estimated 7,677 nautical miles by ocean tanker to Los Angeles.
Neste’s process generates a propane-rich off-gas as a co-product. The high pressure portion of this off-gas (both high- and low-pressure gas is generated) is conveyed via a dedicated pipeline to a hydrogen plant located on Jurong Island. There, it displaces natural gas that would otherwise have been consumed as both a process fuel and a feedstock at the steam-methane reformer. The hydrogen supplied at the Jurong Island plant is piped back to the Neste plant where it is used for hydrotreatment. The low-pressure propane-rich off-gas is sent to a natural gas steam boiler that provides process heat to the RD plant.
Neste calculates the CI for RD from New Zealand tallow to be 36.57 gCO2e/MJ, including a 3.09 gCO2e/MJ credit for the natural gas displaced by the propane-rich off-gas from the RD plant.
Ethanol. POET Biorefining Chancellor (Chancellor) produces ethanol from corn and sorghum at a dry mill plant in Chancellor, South Dakota; the plant can produce up to 120 million gallons of undenatured ethanol per rolling twelve-month period. The plant utilizes biogas and waste wood products in addition to natural gas (NG) and electricity for process energy. The biogas originates as landfill gas from the Sioux Falls Regional Sanitary Landfill (SFRSL). It is collected and processed at SFRSL, and delivered to the plant via a dedicated pipeline.
NG, which is delivered to the plant through a separate pipeline, is used in the distiller’s grains with solubles (DGS) dryers, in the thermal oxidizer, and in the boilers during periods when biogas from the landfill is unavailable. The plant obtains NG and electricity from local utility distribution grids. The plant dries 100% of the DGS it produces. Both feedstocks are obtained from Midwestern suppliers.
Chancellor applied for one corn and one sorghum ethanol pathway. Adding to the complexity of the plant’s process power mix is the fact that the biogas the plant utilizes results in a carbon intensity (CI) credit for the methane emissions avoided at the SFRSL.
Chancellor calculates its corn ethanol to have a total CI of 63.88 gCO2e/MJ (30 of which is indirect); the sorghum ethanol has a calculated total CI of 67.50 gCO2e/MJ (30 of which is also indirect).
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