Schur Ecofuel

[Msilbernagel]

This thread is started for discussion of Hans Schur's "Ecofuel", an alternative fuel best labelled as a vegetable oil blend (not biodiesel).

The following description is a translation from the German Wikipedia pages. The translation has been slightly edited below for readability.

Schur mixture from Wikipedia, the free encyclopedia

The Schur mixture is named after H. Schur. Invented approximately 1993, his idea consists of a procedure which uses pure vegetable oil (Pöl, or SVO) and a mixture of other materials in relatively small portion for use in conventional (unmodified) diesel engines.

Normally, unblended (pure) SVO has a substantially higher viscosity than conventional Diesel fuel. Furthermore the flashpoint is higher, which causes starting problems with cold weather and cold engines.

In October 2000 published report describes the results of its experiments with “SCHUR ECOFUEL”, calling it a Diesel fuel substitute.

Some driver's of direct-injection engines (e.g. the Cummins) are running on this mixture today, despite known issues found in various (unrelated) tests using 100% vegetable oil in unmodified diesel engines and fuel systems.

Production, components:

The vegetable oil forms the largest proportion of the blended mixture at approximately 80%. Two additional components of gasoline and Isopropyl Alcohol (IPA) provide the remaining 20%. The mixing proportion can be adapted depending upon weather and individual experience with each engine, following basic principles (see below) to to improve performance as needed. (Mark: 80/14/6 is the ratio I see most commonly mentioned)

Principle:

Two components, two goals: Gasoline is a suitable additive for reducing viscosity, making the vegetable oil less 'thick'. Even 10% gasoline in the SVO makes a substantial difference. Thus the fuel can be better atomized by the injectors into the combustion chamber, yielding better ignition. A further effect is a so-called cascade ignition. Even with gasoline's tendency to resist self-ignition (low cetane), the volatile fuel supports the burn after the ignition of the mixture. (Mark: diesel starts, gas is lit by diesel)

The isopropyl alcohol is the opposite of gasoline in that IPA does self-ignite under pressure (as required for a good diesel combustion cycle) and causes ignition of the mixture at lower compression temperatures than with pure vegetable oil (approx. 300°C).

In interaction these factors result in a fuel mixture that without transesterification processes (as with bio Diesel), approximates the combustion and performance characteristics of the fossil fuel, Diesel.

Byhttp://de.wikipedia.org/wiki/Schur-Mischung “

Category: Combustion engine

More to come...

FYI - Mark