GLYCERIN OPTIONS: SOAP, COMPOST, AND ANAEROBIC DIGESTION

Dickinson College Biodiesel Shop

Carlisle, PA

The Dickinson Biodiesel Shop

Introduction to glycerin byproduct

� Crude glycerin classified as a haz mat

� Complicates storage, transport, and disposal

� Worldwide glut of crude biodiesel glycerin

� Pays to have a plan before getting stuck with a problem

What to do with glycerin backlog?

� glycerin soap production

� composting glycerin

� creating biogas digesters

For starters, do methanol recovery!

Recover the methanol! It’s not much harder than

making biodiesel

Safe handling of glycerin with methanol

Option one: soap making

Using methanol-free glycerin to make soap

Step-by-step soap making

Step-by-step soap making

Step-by-step soap making

Soap recipes that work!

Liquid soap recipe1 L KOH based glycerin900 mL water61 g KOH

Solid soap recipe1 L NaOH based glycerin200 mL water30 g NaOH

Making bar soap is more difficult…

� Failed batches

� Sweating

Marketing Soap

� Methanol content: flash point test

� Soap survey

� The Dickinson shop’s marketing locations

� The Brown Soap Company

� http://www.thebrownsoapcompany.com

Option two: composting glycerin

� Is composting just disposal, or is there a benefit? Is there a detriment?

� Everyone says glycerin can be composted, but there is currently no conclusive data available

What is composting?

� Composting is aerobic digestion of organic wastes

� Composting is NOT dumping waste in a hole in the ground

Composting basics

Small scale: 3’x3’x3’ Large scale: 8’ windrow

Composting basics: ingredients

� “Greens and browns”

� C:N ratio of 30:1

� Moist, but not too wet

� Good structure to allow air flow and prevent anaerobic digestion

Glycerin composting basics

� Cover piles to prevent rain saturation; compostex fabric

Glycerin composting research

� Trial 1: 10 piles; base of hay mixed with cow manure

� Trial 2: 6 piles; base of wood chips mixed with horse manure

� Trial 3: 4 piles; base of fall leaves with waste food

Glycerin composting research:adding the glycerin

• Five Saturation levels established

100% = 18 gallons glycerin

75% = 13.5 gallons glycerin

50% = 9 gallons glycerin

25% = 4.5 gallons glycerin

0% = 0 gallons glycerin

Cucumber bio assay using trial 1compost and soil additives

Compost:potting soil

ratio

% saturation (glycerin)

1:0 0%, 25%, 50%, 75%,

100%

2:3 0%, 25%, 50%, 75%,

100%

1:3 0%, 25%, 50%, 75%,

100%

0:1 0%, 25%, 50%, 75%,

100%

Cucumber bio assay using trial 1 compost and potting soil

Data and preliminary analysis

Cucumber bio assay using trial 1 compost and vermiculite

Data and preliminary analysis

Berlese funnel bio assay using trial 1 compost

Temperature data from trial 3 piles

Temperature data from trial 3 piles

Option three: biogas digesters

� Anaerobic digestion of organic matter into biogas and soil additives

� Research being conducted for large scale production

� Contracting with Robert Crosby of Biorealis Systems (www.biorealis.com) for small scale production research

� First attempts show possibilities

� Further research is underway

� Inoculate

� Feedstock

� Processor Design

� Glycerin feed levels