Biodiesel Cold Soak Filterability - ASTM D6751 Annex A1

New ASTM Biodiesel Test Specification for Cold Weather Operability

The American Society for Testing of Materials has recently added a new test requirement to the D6751 Biodiesel Specification.

This new requirement is referred to as ASTM 6217 or as Annex A1 of ASTM D6751– Cold Soak Filterability.

Cold Soak Filtration Analysis is defined as: The time in seconds that it takes for cold soaked biodiesel to pass through two 0.8 micron filters and the amount of particulate matter expressed in milligrams per liter (mg/l) collected on the filter.

What does this mean? When biodiesel is stored in temperatures below 40°F for extended periods of time, certain components will precipitate (fall) out of solution and fall to the bottom of the storage tank. This precipitate will build in a thickening layer at or near the tank bottom. In general the colder the temperature and the longer the biodiesel stays at a given temperature, the more material will fall out.

This material can very quickly plug filters and shut down engines, usually at the worst time.

What is this material? It can have to do with the feedstock from which the biodiesel is created. Certain feedstocks, particularly Used Cooking Oils (UCO), Waste Vegetable Oil (WVO), and Animal Fats (Tallow) will produce high levels of precipitate. The material can also be due to incomplete removal of glycerin during the transestrification process.

This new test is a positive step in making biodiesel a more consistent user friendly product.

Diesel Doctor

Copyright 2009© - William Richards

Synthetic Oils - Are they Worth the Cost?

Synthetic Oils - Are they Worth the Cost?

Image courtesy of outboardmotoroilblog.com

Today we hear a lot of terms thrown around when discussing motor oils. Much of the time, they are being used incorrectly.

So let’s start with mineral oil, this is the oil most of us have used in one form or another since the internal combustion engine was created. Mineral oils are distilled from crude oil as part of the refining process.

There are three categories of mineral oils; Paraffinic, Naphthenic, and Aromatic. Mineral oil can be as simple as baby oil, or as complex as today’s heavy duty motor oils. The chemistry used to create multi-grade oils and pickup and hold contaminants in solution is extremely complex.

Synthetic – Synthetic Oils can be created from many different sources and can offer many helpful characteristics such as lower friction, better high temperature performance, better stability, better sheer stability, better cold start lubrication, reduced oxidation, improved protection against thermal breakdown, less tendency to form sludge, reduces evaporative loss, potentially extends drain intervals.

There are two main categories for synthetic oils the first is:

Polyalphaolefin (PAO) an American Petroleum Institute (API) Group IV Oil Base Oil

The second is:

Synthetic esters an API Group V Base Oils ((non-PAO) synthetics, including alkylated naphthalene’s, alkylated benzenes, diesters, polyolesters, polyglycols etc.)

There is also a category called Semi-Synthetics – a mixture of petroleum and up to 30% synthetic base oils. The name Semi-Synthetic is a misnomer, oils are either Synthetic or not. If they are a mixture then if you subscribe to the theory that a chain is only as strong as its weakest link applies and the mixture will only be as good as worst performing part of the mineral oil.

The primary reasons to change motor oil are because the oil gets dirty and or because the additive package in the oil gets used up. Dirty can mean physical dirt from the environment, soot from combustion, left over combustion products and a nearly endless list of contaminants.

The additive package provides friction reduction, neutralizes acids, holds contaminants in solution, prevents oxidation, prevents corrosion, and many other vital functions. The additives are consumed or used up over time and they need to be replenished or failure will result. The method most often used is to replace the oil. This method has the advantage of taking many or hopefully most of the contaminants out of the engine with it.

Synthetic Oils may or may not have super additive packages, but eventually the oil becomes dirty to the point that it needs to be filtered or replaced and the additive package replenished or again replaced. The problem is that synthetic oil becomes contaminated long before it is “worn out” and has to be replaced to prevent damage from the contaminants. This means that often you are unable to take full advantage of the superior chemistry and characteristics of synthetic oils.

When this happens the cost disadvantage of the synthetics outweigh its other advantages.

In situations of extreme cold, high heat, high loads, extended operation at high rpm, and other related situations synthetic oils offer many superior characteristics that may improve operability, increase engine life, provide better fuel economy, and potentially improve emissions.

However for the average grocery getter or most vehicles in normal operation the added cost of synthetic motor oil is probably not justified.

View all of the Fuel School articles at: www.lcbamarketing.com and click on Technical Articles

Please post your comments, thoughts, ideas, and suggestions.

Diesel Doctor

Copyright 2009© - William Richards

E-Diesel – A Fuel for the Future?

E-Diesel – A Fuel for the Future?

Image Courtesy of University Of Illinois

E-Diesel is a blend of Ethanol and Diesel Fuel together with a multifunctional additive package. E-diesel is typically a 7% to 15 % blend of Ethanol in #2 diesel fuel together with 2% to 5% of additive. Early on it was referred to as “Oxygenated Diesel”, now however; most call it E-Diesel.

E-diesel is popular in Brazil as they produce a large amount of Ethanol from biomass left over from growing and processing sugar cane. Brazil has a limited supply of domestic crude oil and this has given them a huge incentive to develop alternative fuels and their government has stepped up to the plate to make it happen.

As a result Brazil is today an energy independent country, something we should aspire to become.

E-diesel has not been popular in the US, although it has been tested in some large fleets here with mixed results.

However the problems with Ultra-Low Sulfur Diesel, with Biodiesel being forced into our diesel and the recent very high price of fuel (now temporarily better) have made this technology worth another look.

E-diesel has a number of negative characteristics, it is hygroscopic (soaking up huge amounts of water if allowed to do so), Ethanol lowers the flash point of the diesel, Ethanol destroys lubricity in the fuel, and Ethanol makes the fuel less stable.

The pluses are that it improves cold weather characteristics, lowers CO and NOx, potentially (when derived from cellulosic biomass) lowers cost of the finished fuel, and increases the amount of non-petroleum renewable fuel available.

E-diesel using Ethanol produced from Bagass (the parts leftover from making sugar from sugar cane) is winner. Ethanol made from corn is a loser, the yield is very low, and it affects human and animal feedstocks.

The biggest winner is if you make diesel fuel from algae and use the biomass left over to produce Cellulosic Ethanol which can be burned in boiler, added to gasoline, or added to diesel. It is possible that Ethanol produced in this manner could cost as little as $1.00 per gallon.

The potential of producing a high quality cellulosic Ethanol from biomass is a game changer.

Ethanol in fuels presents significant problems in many areas. However these problems can be overcome or managed through changes in the way we handle fuels and blending, changes in equipment using these fuels, and though the use of properly formulated additive packages.

For more information please go to: http://www.lcbamarketing.com

Please comment with thoughts, ideas, and suggestions.

Diesel Doctor

Copyright 2009© - William Richards

What Happens when Gasoline is Burned in an Engine

What happens when gasoline or other petroleum fuel is burned in an Engine?

Gasoline (or any petroleum fuel) is mostly carbon that when burned releases energy in the form of heat. This heat energy makes the engine run and allows it to do work.

The bad part of this process is that the carbon when burned is converted into Carbon Dioxide (CO2). Imagine that a gallon of gasoline weighs between 5.93 to 6.42 lbs (depending on type, temperature, blend and other factors) and as it is burned most of it is converted into CO2 weighing between 5 and 6 lbs per gallon.

If this CO2 was a visible solid, you would have to constantly plow the roads as it would build up like snow in a blizzard. But as it is an invisible gas that floats away, nobody pays any attention to it.

Now imagine that worldwide we burn 80,000,000+ barrels (3,486,000,000+ gallons) (Note: The US uses approximately 25,000,000+ barrels or 1,050,000,000+ gallons) of oil per day and 90% - 95% of that becomes CO2.

That’s 20,916,000,000+ lbs. (Twenty Billion, Nine Hundred Sixteen Million Pounds per Day) of CO2 per day, an incredible amount of carbon that we expect the atmosphere to magically absorb. Again if this was a visible solid, we would be buried in a matter of weeks.

Now, I am a proponent of diesel engines, if for no other reason that they are far more efficient than gasoline engines (30+%). If the portion of this fuel that is refined into gasoline was instead refined into diesel you would reduce that consumption by 30+%.

If you capture CO2 from the atmosphere or better yet from the source and use it to grow algae or other plants, you are using photosynthesis to sequester this carbon. If that biomass is then converted into a biofuel and burned in efficient manner you have formed a closed loop where you can nearly stop the increase of carbon released into the environment.

I believe that short of someone developing cold fusion, the development of algae oil biofuels is our best choice for continued use of liquid fuels. This technology could be made commercially viable in just a few years and produce a high quality oil that could be converted into diesel and other fuels for about $20.00 per barrel. Even if I am wrong by 100%, the cost would still be where the cost of crude is today (02/25/2009).

These are things we need to be thinking about. What’s your opinion?

Diesel Doctor

Copyright 2009©- William Richards

Fuel Storage Tank Maintenance - Keep It Clean

Keep It Clean - Fuel Storage Tank Maintenance

Most owners and operators of fuel storage tanks do not understand that maintenance is required to safely and successfully operate fuel storage tanks.

We constantly hear that customers have tanks that have never been cleaned and worse yet, that they believe that they never need to check to see if they have any problems.

This is made even worse by the information that some fuel suppliers tell their customers; for example that it OK to have some water at the bottom of the tank.

Well here is some real world information for everyone on this subject.

Fuel Storage Tanks all require regular maintenance. They are designed with the pickup tube 3" to 6" from the tank bottom so that small amounts of water, sediment and other contaminants have a space they can settle out so that they will not be drawn into the vehicle or equipment tanks as fuel is pumped out. This water and sediment material will accumulate over time and will cause problems if not removed periodically.

Some will tell you that 1/2" or 1" or even 2" of water is alright, and they are flat out wrong. Every time fuel is transferred into that tank it stirs up all that material and it may take as long as a day for it to settle out again. In the meantime every tank you dispense fuel into gets some of this material.

If you have a steel tank that water is corroding your tank from the inside out and putting rust particles into your fuel. We often find above ground tanks only a few years old that have rusted from the inside to the point of leaking from water and sludge in the tank.

Many customers have electronic monitoring systems that provide constant readings showing fuel level, water level, and leak detection. Some of these customers will see 1/2" or a few gallons of water on these system and ignore it because they have been told it is not important.

One problem we see time and again is that the sensors on these monitoring systems fail and they don't tell you when they fail, they just go on showing the last reading forever. This goes on until they start pumping water into their equipment at which point someone checks the tank with a stick and water finding paste only find that they actually have several inches of water.

We have told all of our customers for many years that even though you have spent several thousand dollars for a state of the art monitoring system, you still need to have some one check every tank at least once a month with a stick and water finding paste.

And this rule should be written next to the monitor and maybe next to where you store the measuring stick: "The Only Acceptable Amount of Water in Any Fuel Storage Tank is ZERO (0)".

For those of your with in-ground steel tanks, these tanks have Sacrificial Anodes attached to them. These Anodes take the weak electrical current generated by the tank and pass it into the ground through them. This prevents the tank metal from corroding, however the Anode "Sacrifices" itself in this process. The Anode is used up over a period of time. When the Anode is "used up" the tank begins to corrode often very quickly. Tank owners should periodically check these Anodes and Replace them as necessary. In many states this is part of the required maintenance and testing procedures, however you should know this and check to be certain it has been properly done.

Caps, Sumps, and Vents should all be checked for integrity and to see that they are doing their intended job.

Fuel Storage is a vital link in getting clean fresh fuel safely and efficiently into vehicles and equipment. You have a big investment in the tank, its installation, and in the fuel in it. It only makes sense to properly maintain and protect this investment.

Today we have new challenges with Ultra-Low Sulfur Diesel (ULSD), Biodiesel, Gasohol, Conventional Gasoline, and Reformulated Gasoline containing any amount of Ethanol. These fuel products hold much higher levels of water and are much more corrosive than fuels we have traditionally dealt with. They require much higher levels of monitoring and maintenance to have a safe and trouble free delivery system.

We are happy to offer analysis and suggestions on how to operate and maintain your systems.

Please post your comments or questions here.

Diesel Doctor

Fuel and Water - They Don't Go Together

Fuel and Water

They don't mix and you shouldn't try to make them.

One of the more interesting characteristics that is shared by diesel, biodiesel, gasoline, and gasohol is that all these fuels are hygroscopic.

Hygroscopy is the ability of a substance to attract water molecules from the surrounding environment through either absorption or adsorption.

Some examples of this phenomenon are that Ultra-Low Sulfur Diesel (ULSD) will hold approximately 2/10 of 1% dissolved water. This may not sound like much, but if you do the numbers they show that 2/10 of 1% equals 2 gallons of water dissolved in 1000 gallons of fuel. If you work backwards, that would equal 1 gallon of water in 500 gallons of fuel, or 1 quart (32 ozs.), in 125 gallons, or 1 pint (16 ozs.), in 62.5 gallons, down to about 8 ozs. in a 30 gallon tank.

That much water can cause severe corrosion of fuel system components such as injectors, pumps, connectors, and even metal fuel tanks.

That level of water speeds the oxidation and chemical breakdown of the fuel.

That level of water is enough to encourage the growth of bacteria and fungi.

One of the most insidious characteristics of water dissolved in fuel is that the fuels ability to hold water is dependent on temperature. Simply put the warmer the fuel (up to a point) the more water it hold.

What often happens is that fuel stored for example at 60°F will absorb that 2/10% water then as the fuel in a vehicle gets colder more and more of that water is pushed out of the fuel becoming liquid water droplets.

These droplets can collect in filters and if the temperature drops below 32°F those droplets turn to ice crystals quickly plugging filters and causing other problems.

Fuel at 28°F can hold approximately 1/2 as much water as fuel at 60°F.

This means that you can have clear fuel with no liquid water at 60°F and if the temperature drops sufficiently, you can have large amounts of free water suddenly appear as the temperature drops.

To make matters worse biodiesel can pickup and hold 10 times as much water as ULSD. So adding 2% or 5% biodiesel to regular diesel can dramatically increase the level of dissolved water.

Gasoline containing Ethanol suffers the same problem.

A 10% Ethanol blend can hold 3.8 teaspoons of dissolved water at 60°F.

However if more water is added or if the temperature drops significantly this fuel suffers a problem called "Phase Separation".

In Phase Separation the dissolved (or liquid) water binds to the Ethanol and this Water/Ethanol mixture will drop out of the fuel.

This has a series of negative affects on the fuel quality and can have catastrophic effects on engines.

We will discuss more about this later.

We look forward to your comments and questions.

New Cold Weather Problems with Biodiesel Identified

New Cold Weather Problems with Biodiesel Identified

The recent bout of very cold weather in the northern tier states has shown new issues with biodiesel blends containing as little as 2% biodiesel.

We are seeing a significant number of customers that are having problems with the filters on their diesel fuel dispensers.

In nearly every case the customers are receiving a B2 to B5 blend.

In most of these cases they are not having vehicle or equipment problems, but rather problems getting the fuel from the storage tank to the vehicle tank. The dispenser filters seem to plug anywhere from a few hours to a few days of operation.

These filters when opened contain what at first appears to be wax. However when analyzed this material appears to be a glycerin type material. If you then bottom sample the storage tank, you generally find a material that resembles cottage cheese. There is often a layer that starts at the tank bottom and can be several inches thick of this material.

When this layer reaches the level of the pickup tube it can very quickly plug the dispenser filter.

This issue has several variations and we have identified several potential causal factors.

1. 
   Fuel that has a high level of dissolved water. This high water content seems to be a significant factor in all of these cases.
2. 
   Fuel derived from animal fats (including plant / animal blends of biodiesel) seems to be a factor in these problems.
3. 
   Long periods (more than 72 hours) of temperatures below 32 °F (the longer it is cold and the colder the average temperature the greater the problem).
   Above ground versus in-ground fuel storage.
4. 
   Use of additives – Some help, some make things worse.
   CP, CFPP, PP of the diesel portion of the blended fuel.
5. 
   Quality of the blend procedure and temperature at which the fuel and biodiesel are blended.
6. 
   Storage period.

Another factor in the rapid plugging of these dispenser filters is that as filter media starts to plug the filter actually begins to reduce the micron size of the media so that the filter picks more and more material that is smaller and smaller.

Also consider that a diesel engine tends to heat the fuel during the recirculation process whereas a dispenser provides no heat.

We offer some suggestions for users experiencing these problems.

1. 
   If you have this problem today you can go to a dispenser filter with a large micron size. There are winter filters available from Cim-Tek with a cleanable 144 micron stainless steel mesh.
2. 
   You can have the tank pumped from the bottom to remove this material. Depending upon your tank size, you may need to remove 50 to as much as 300 gallons to eliminate this problem.
3. 
   You can add certain types of additives that will break this material down and return it to solution.
4. 
   You can add kerosene (Note: if you have Ultra-Low Sulfur Diesel, you MUST use Ultra-Low Sulfur Kerosene). ULSD Kerosene is very expensive and it can take a lot of it to resolve this problem.
   Ask for your next two or three loads of diesel to be delivered with no biodiesel.
5. 
   Ask for biodiesel blends derived only from plant base oils during the fall and winter months.
6. 
   Additization with the correct products can help to prevent these problems.
   If you have access to biodiesel that has been through a distillation process, you will have far less problems.

Please let us know about your experiences with these problems

Biodiesel Confusion New Labeling Requirements

Biodiesel Confusion

The diesel fuel/biodiesel market has recently gotten a lot more confusing. We now have another Federal agency involved in the diesel fuel marketplace.

The Federal Trade Commission (FTC) has now created labeling requirements for diesel, biodiesel, and biomass based diesel.

These requirements have wide ranging consequences for all diesel fuel users.

First, diesel fuel may now contain up to 5% biodiesel or biomass-based diesel with no retail labeling required as long as the blended product meets ASTM D975 (note: ASTM D975 is being changed to allow up 5% biodiesel/biomass-based diesel to be blended as part of a diesel fuel).

Second, there are (according to the FTC) now two types of biodiesel, the first is the one most people are familiar with, where a plant, seed or animal derived oil is through transestrification converted to a Methyl Ester that is defined by ASTM D6751 and commonly referred to as biodiesel. The other is known as “Biomass-based Diesel”, this a fuel derived from biomass that does not contain Methyl Esters (note: there currently is not an ASTM specification for this product).

Third, effective December 16th, 2008, all retail fuel pumps are subject to the following labeling requirements based on Section 205 of the Energy Independence and Security Act of 2007 (EISA): Fuel blends containing no more than five percent (5%) biodiesel or no more than five percent (5%) biomass-based diesel and that meet ASTM D975 require no label.

Fuel blends containing more than five percent (5%), but no more than twenty percent (20%) biodiesel require a dispenser label 3”w x 2.5”h with a Blue background and a Bxx reporting the exact percentage or “Between B5 and B20” statement.

Fuel blends containing more than twenty percent (20%) biodiesel require a dispenser label with a Blue background and a Bxx reporting the exact percentage or “Containing more than 20% biodiesel statement.

Biodiesel that is “neat” or B100 must be labeled as “B100 Biodiesel” and “Contains 100 percent Biodiesel” on a Blue background.

Fuel blends containing more than five percent (5%), but no more than twenty percent (20%) biomass-based diesel require a dispenser label 3”w x 2.5”h with an Orange background and text reporting the exact percentage or “Between 5% and 20% Biomass-based Diesel” text statement.
Fuel blends containing more than twenty percent (20%) biodiesel require a dispenser label with an Orange background and text reporting the exact percentage or “Containing more than 20% Biomass-based Diesel” statement.Biomass-based Diesel that is “neat” or 100% must be labeled as “100% Biomass-based Diesel” on an Orange background.

Note: You should visit the FTC website at: http://www.ftc.gov/ at look at: 16 CFR Part 306 - RIN #3084-AA45 for more complete information on these requirements.

What this means in the real world is that suppliers can now add up to 5% biodiesel in retail fuels without notification to customers.

If you want biodiesel and have done your homework on what is required to successfully and safely use this fuel you should note what you want as you order your fuel.

If you do not want any biodiesel you should issue a written purchase order to your supplier telling them exactly what you want, e.g. no biodiesel.

Note: under the new ASTM D975 spec, 5% is allowed.

Biodiesel and Cold Weather Issues

We have recently seen a new cold weather problem related blended biodiesel fuels.
The problem has been seen with B5 and greater blends where the diesel portion has been treated with certain lubricity agents.
What is being seen is that when the stored fuel is cold (below 15F) for extended periods of time (generally 48 hours or more) the dispenser filters will plug with an orange colored material. When this fuel filter is removed and the fuel poured out into a container that will allow it to be viewed you see an orange cloud floating in the fuel. The colder it gets the more of this material is found in the filter.
This appears to be the result of the fuel becoming more viscous as it gets colder. As the fuel becomes thicker it will begin to reduce the pore size of the filter media. As the pore size gets smaller, the filter begins to filter out the lubricity additive and the filter will concentrate it until the restriction is such that little or no fuel will pass through the filter.
This is a separate issue from gelling. The fuel when tested can have a very good CFPP or LTFT number and still see this problem.
If anyone has seen this issue, please let me know and I can offer suggestions for how to deal with this problem.