Backyard Biodiesel - How do you know about the quality?

The following letter was written by one of our members to some people in New Zealand who were seeking to determine a national standard for their own home made biodiesel production.

It highlights some of the issues that we have here in Australia relating to this issue. It discusses the issues of national fuel standards being more about politics than about the fuel quality.

This is a good read for anyone who is concerned about making sure they make quality biodiesel at home.

Original letter follows below:

RE: HOMEMADE BIODIESEL

STANDARDS I note from the reply sent by XXXXXX office that there is a development and implementation of a national standard for biodiesel that may be in place by the second half of 2005. I have some experience with the biodiesel standard debate which I will relate.

While working with the Papua New Guinea government on a proposed biodiesel project for Kar Kar Island, I had emphasised that any standards that are set should be only those necessary to prevent problems. I still stand by that position as anything more than that becomes political. It has been my experience that many issues regarding standards relate to influence brought upon the government by a feedstock provider or by manufacturers of biodiesel processing equipment.

 As you know from previous correspondence, I have been involved with various discussions with the Australian government. Here is a quote from a letter to Senator Coonan of 1 April 2004 –

 - Quote –

FUEL STANDARDS

First from a legal perspective, there is no need for fuel standards for homemade biodiesel made for personal consumption. Under the Fuel Quality Standards Act 2000 Sec. 12 creates the offence of supplying non-standard fuel. In Sec. 4 of the Definitions, supply is defined as - “supply” means supply (including re-supply) by way of sale, exchange or gift. However, using a political and/or practical perspective to the view on fuel standards can reveal more complex issues, as many times the standards are set for political reasons not technical reasons. For example, in Europe the former DIN standard was used to keep American soy based biodiesel from being marketed in Europe. The Europeans created a fuel standard that required a maximum iodine level that the European rapeseed could meet, but the American soy bean could not. The iodine level has absolutely nothing to do with the performance of the fuel; the standard was solely a political move.

I should draw your attention to the Australian biodiesel standard as that standard may become a contentious issue in debate. In particular, the requirement for a minimum cetane level of 51. The cetane level is a diesel fuel rating related to its igniting ability, similar to the octane rating for petrol. It has never been explained why the biodiesel standard was set so high. Many of the seed crops in Australia that could be used for biodiesel cannot be used to make biodiesel with a cetane level of 51. For example; safflower oil (49.8), soybean oil (46.2), sunflower oil (46.6) and waste vegetable oil (WVO) from shops and restaurants that contain many of these oils. In fact, one of the most desirable sources of quality WVO for the home brewer comes from Asian restaurants, which use soybean oil almost exclusively – biodiesel made from that oil would fail to meet the cetane standard. Now here is the government’s problem. You see the cetane level for petroleum diesel is only 46 (Fuel Standard (Automotive Diesel) Determination 2001 – Sec. 3(3)).  As you can see from my above comments, it is a fact that ALL biodiesel made from any feedstock will exceed a cetane level of 46. In other words, the Australian petroleum diesel standard cannot meet the Australian biodiesel standard for cetane. It gets worse, the Energy Grants (Credits) Scheme Regulations 2003 specifies a minimum cetane of only 35! So why biodiesel was set at 51 is anybody’s guess. Moving on to safety aspects of the standards of the fuels we see that petroleum diesel must have a minimum flashpoint of 61.5C (see Sec. 5(2) of the above Automotive Diesel Act) whereas biodiesel must have a minimum flashpoint of 120C (see Sec. 4(2) of the above Biodiesel Act). Clearly, biodiesel is considerably much safer than diesel fuel and so much so that petroleum diesel cannot even begin to meet the biodiesel standard.

To illustrate these two concepts of cetane and flashpoint; I have often added homemade biodiesel to some poorly manufactured petroleum diesel to improve the performance of the fuel, that is, to raise the cetane level so that the engine would idle better. Further, if a person puts diesel or kerosene in a kerosene lantern it will burn, but if you put in biodiesel the flame will go out.

Whether or not it is true, there are many in the biodiesel industry that believe the biodiesel cetane level was set at 51 is so that cheap imported palm biodiesel (cetane 52+) from Asia could receive the government tax advantages and grants under the new grants scheme. When one looks at the lack of gel point and cold filter plug point specifications in the biodiesel standard, it tends to corroborate this position.  On a practical basis, I will also state that standards are usually broad enough to cover potential litigation problems for a broad range of users. However, a person who makes homemade biodiesel can customize the biodiesel for their own engine. Commercial biodiesel has a conversion rate of around 96%. However, it has been found that a conversion rate of 90% is adequate for most direct and indirect injection engines. Many home brewers with indirect injection engines will seek to save a bit of money and produce 85% conversion fuel for their engines – it works just fine with no problems.

- Unquote-

WATER CONTENT

Although trace amounts of water in biodiesel may seem prima facie relevant, when one looks at the moisture issue in more depth it doesn’t, shall we say, hold water. I draw your attention to the work of Lubrizoil and Citgo in America and CamTec in Europe. Those firms have developed diesel fuels that incorporate large quantities of water in the fuel. The fuel utilizes chemical emulsifiers to keep the water in suspension. The water content of the fuels can reach 20 PERCENT!

Compared to the large quantity of water used in those fuels, the miniscule amounts of moisture that may result from the biodiesel production process, including washing without drying, is so small as to be negligible.

Let’s look at this water issue more closely. Although biodiesel is much more environmentally friendly than petroleum diesel, the only emission pollutant that exceeds the levels of petroleum diesel is nitrogen oxides. The use of a bit of water in the fuel reduces the nitrogen oxide emissions of the fuel. So, if we were really trying to design a more environmentally friendly biodiesel fuel then we should actually be encouraging a bit of water in the biodiesel.

I understand that both of you have made biodiesel, so you know that during the process of making biodiesel a person may use a water wash to remove water soluble elements in the fuel. If that water wash has been fairly aggressive then the biodiesel will contain fine droplets of water. Usually a drying process of some sort is then used to “dry” the biodiesel. However, from personal experience, I can confirm that if the biodiesel is not dried, but simply put in the tank and run as “wet” fuel – there is no perceivable difference in performance.

The only real issues of concern about the water in the fuel is whether it might drop out of suspension or result in corrosion. Those issues will be dealt with shortly.

FLASHPOINT/ALCOHOL LIMIT

I have dealt with some aspects of the flashpoint issue in my comments to Senator Coonan. The balance of the issues related to the alcohol content can be summed up with a reference to DIESOHOL (sometimes referred to as E-Diesel).

As you know, diesohol is a fuel wherein 10% ethanol (and a bit of emulsifier) is added to  petroleum diesel. I have tried such fuel produced here in Australia and I did not experience any problems. I find it paradoxical that the Government can on one hand authorize the inclusion of 10% alcohol in a fuel, and then turn around and command through “standards” that lesser percentage amounts of alcohol in a diesel fuel are prohibited.

Here is a trick that homebrewers have used when confronted with “wet” biodiesel and have an urgent need to use the fuel without drying it. They simply add a bit of alcohol to prevent the fine water droplets from dropping out of solution. It has been found that Isopropyl alcohol works best and it may only take 1-2% Isopropyl alcohol to instantly clear the biodiesel and put the water in solution.

Of course, this fuel would not meet any international standard - but it is possible that it would be a more environmentally friendly fuel than anything else on the market. By thinking outside the box, one could imagine a scenario whereby a country could actually mandate through its standards that a small amount of water be included in the biodiesel and that is should be held in suspension with locally grown and produced ethanol.

SOAP

During the process of neutralizing the FFAs in a feedstock, there is the production of soap. Significantly, this soap has a high PH.

It is acid that etches a steel component, not a base. A small amount of soap introduced into the fuel will neutralize acids in any water that has settled in the fuel tank. A small amount of soap in the fuel will prevent any rust from attacking the important components in a fuel pump or fuel injector.

A little soap is good, so the question then becomes how much soap is too much? Well, so far the homebrewers have never been able to reach that limit.

“Unwashed” biodiesel has a long history of use around the world. As you know, unwashed biodiesel still contains trace amounts of alcohol (usually 3-4%), glycerin and soap. There is anecdotal evidence from thousands of users over millions of miles/kilometers is that there is no effect to any component from the ingestion of the soap left in unwashed biodiesel. I might add that the anecdotal evidence is obtained from people that are using the unwashed biodiesel in a neat form and not blended.

The amount of soap that can be ingested by an engine is so far undetermined. I have used biodiesel that has only settled for one hour in vehicles. Using biodiesel with this limited amount of settling time guarantees that around 10cc of soap/glycerin will be ingested into the engine for each litre of fuel that is burnt. There is no build up of deposits in the combustion chamber, nor the exhaust system. There are issues related to fuel filter clogging when using poorly settled unwashed biodiesel, but even those problems are all manageable.

The extreme limits of soap/glycerin ingestion has been tried using “un-separated” biodiesel. This is a new concept that is still being worked on. So far, there have been no reported problems, but initial work has only been done with vegetable oil and very low FFA feedstock. This type of biodiesel fuel uses ethanol rather than methanol for the chemical reaction. Whereas biodiesel production using methanol is a very easy process, ethanol is much more difficult to work with and usually results in biodiesel where the glycerin/soap does not or does not fully separate from the biodiesel. This trait of the ethanol reaction is capitalized in this new type of fuel. The idea is to create a fuel wherein the glycerin/soap remains fully suspended in solution – and the whole lot is used as fuel.

In a world that is rapidly running out of liquid fuel, this un-separated biodiesel could  significantly increase the amount of fuel that is available. Whereas, excess alcohol is normally removed from the production process with the glycerin/soap, in this type of fuel the alcohol is used to help reduce the viscosity of the glycerin/soap component of the fuel. There is no loss by extracting either the glycerin or the alcohol.

GLYCERIN

I note that New Zealand has already experimented with straight canola oil as a diesel fuel. The usual problems associated with this kind of fuel relate to viscosity, which may effect mechanical components, and FFA that causes corrosion. Biodiesel eliminates both of those problems. A small amount of glycerin in biodiesel is not a problem – especially when blending is involved.

Again the homebrewers have tried other ways in which to process biodiesel. The efforts are usually related to trying to maximize the amount of fuel for the amount of alcohol that is used. For example, if one makes biodiesel using smaller quantities of methanol the percentage of conversion decreases. This results in more glycerin in the fuel, whether it is by triglycerides, diglycerides or monoglycerides.

In PNG, because of the poverty and lack of resources, I discussed a type of stoichiometric approach to the production of coconut based biodiesel. Coconut oil has a very low Iodine value and is theoretically capable of being run neat in an engine without the build-up that other neat oils suffer. A stochiometric chemical reaction with coconut oil will result in maximum utilization of the methanol and still produce a usable fuel.

Another creative approach which has had some success (and is used to decrease monoglycerides) is to create a high conversion batch using the higher percentages of methanol. Then, before the glycerin is drained off, another quantity of feedstock is introduced into the batch and mixed up with the freshly made biodiesel and glycerin. This further quantity of feedstock is not transesterfied, but instead it has it’s various impurities and the FFAs removed by the glycerin.

CONCLUSION ON STANDARDS

As you can see, there are still considerable issues related to what should or should not constitute biodiesel fuel standards. Returning to the issue of Peak Oil, we need to ensure that any commercial standards that are set for a country are consistent with the overriding need to provide fuel for the country – we simply cannot afford to lose any fuel without a compelling reason. As long as the fuel is free of problems, then anything else which inhibits the production of the fuel should be discouraged.

The issue of standards for homemade biodiesel should not even arise. Humans are not only creative, they are protective of their own assets – especially their vehicles. Homebrewers constantly push the envelope to see how much fuel they can create with little resources – that is something the Government should encourage. The only restriction that should be necessary in regards to homebrewed biodiesel is limiting the use of the fuel for the personal use of the homebrewer.