Anaerobic Digestion Anaerobic Digestion of Biodiesel and of Biodiesel and Biodiesel Waste Biodiesel Waste ProductsProducts

James DuncanJames Duncan

Anaerobic DigestionAnaerobic Digestion

Anaerobic Digestion is the microbial Anaerobic Digestion is the microbial process by which organic matter is process by which organic matter is broken down and digested to produce broken down and digested to produce BiogasBiogas

Biogas is a energy resource usually Biogas is a energy resource usually composed of 60% methane, 40% Carbon composed of 60% methane, 40% Carbon Dioxide and trace amounts of Hydrogen Dioxide and trace amounts of Hydrogen SulfideSulfide

Biology of Anaerobic Biology of Anaerobic DigestionDigestion

Microbial conversion occurs in a community Microbial conversion occurs in a community of microbes found in nature, typically in soils of microbes found in nature, typically in soils and in the guts of organismsand in the guts of organisms

Conversion occurs in the following steps Conversion occurs in the following steps hydrolysis, acidogenesis, acetogenesis, and hydrolysis, acidogenesis, acetogenesis, and methanogenesismethanogenesis

All the conversion steps occur in a dynamic All the conversion steps occur in a dynamic equilibrium between facultative organisms equilibrium between facultative organisms and methanogensand methanogens

Microbial Steps to BiogasMicrobial Steps to Biogas

Hydrolysis breaks down organic matter Hydrolysis breaks down organic matter to increase its bioavailabilityto increase its bioavailability

Acetic, propionic, and other organic Acetic, propionic, and other organic acids are produced during Acidogenesis acids are produced during Acidogenesis

Acetate is produced from the organic Acetate is produced from the organic acids during Acetogenesisacids during Acetogenesis

Methanogenesis is the process by which Methanogenesis is the process by which methane and COmethane and CO22 is produced from is produced from acetate or Hacetate or H22 and CO and CO22

Biodiesel and Biodiesel Biodiesel and Biodiesel Waste ProductsWaste Products

Biodiesel is produced from the Biodiesel is produced from the transesterfication or esterfication of oils transesterfication or esterfication of oils

Waste products include glycerol, oil Waste products include glycerol, oil dregs, and wash waterdregs, and wash water

Waste products and the biodiesel itself Waste products and the biodiesel itself are very attractive feedstocks for are very attractive feedstocks for anaerobic digestion because of the high anaerobic digestion because of the high organic content organic content

Project ProposalProject Proposal

To characterize the To characterize the Biodiesel and Biodiesel and biodiesel waste biodiesel waste productsproducts

Feed the byproducts Feed the byproducts into fixed film pilot into fixed film pilot reactors at UF’s reactors at UF’s Dairy Research Unit Dairy Research Unit to measure gas to measure gas production from production from waste productswaste products