Backyard Biodiesel by Lyle Estill

Author:Lyle Estill [Armantrout, Bob; Estill, Lyle]
Language: eng
Format: epub
ISBN: 9781550925913
Publisher: New Society Publishers
Published: 2015-03-19T16:00:00+00:00

All of this lab equipment will cost about $200, a small investment to be able to ensure producing quality fuel.

In addition to equipment, you’ll need to get lab reagents (chemicals). You can make your own 0.1 N KOH solution by dissolving 5.6 grams of KOH in 1 liter of distilled water. Measure both the KOH and the water very precisely to make an accurate solution. A 1,000 ml volumetric flask (along with your scale) will do the trick, available online for about $15.

That’s the backyard take.

Commercial producers are required to measure and report impurities in their fuel. Methanol, catalyst, glycerin and unreacted or partially reacted oils can all lead to difficulties with your engine and need to meet ASTM D6751 in order to be legal for on-road sale.

Determining the temperature at which it “flashes” typically involves measuring the quantity of methanol in fuel. A sample of biodiesel is heated up in a device called a flash point tester; the fuel should not flash below 93°C. If it flashes below that, wash your fuel again. Flash point testers range from $700 to thousands of dollars, which is why backyard brewers seldom bother with them.

The amount of free glycerin allowable in on-spec fuel is .02% of the overall mass. And the amount of total glycerin, free plus bound (unreacted oils), is .24% of mass. Measuring this number is typically done with a gas chromatograph, which will report on the glycerol, monoglycerides, diglycerides and triglycerides in your fuel. A used gas chromatograph can cost $5,000 and will need a monthly maintenance budget in order to stay happy.

Commercial producers are required to report their acid number. This can be done through manual titration, which reports results visually, or it can be done with an auto-titrator, which measures changes in the conductivity of the fuel. An auto-titrator can cost $600.

A water and sediment number, another important part of the specification, is determined in commercial biodiesel laboratories with a desktop centrifuge. These range from $300 to thousands of dollars.

Measuring the metal content of fuel is also required. Potassium, sodium and phosphorus (which is not actually a metal) are measured using an inductively coupled plasma (ICP) machine. Even used ICP machines can cost close to $20,000.

You also don’t want sulfur in your fuel. This is measured by optical emission spectroscopy (OES) that is typically coupled as an ICP/OES machine. While biodiesel is famous for its absence of sulfur, some feedstocks, such as trap grease, can be extremely high in sulfur and can lead biodiesel to be out of specification.

For $200, and some care, you can make high-quality, on-specification fuel in the backyard. But before you dream of turning commercial, be aware that a single commercial analytical machine can cost more than your entire backyard operation.

Note that not every commercial producer possesses all this gear. Piedmont generates a certificate of analysis for every drop of fuel that ships from its plant. Part of that analysis is generated in our onsite laboratory, which possesses analytical gear; part is generated

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.