Urea – More Things to Consider

Urea - More Things to Consider

I recently heard a new concern for those of you who will be storing and dispensing Urea for the 2010 diesel trucks. Urea is a very corrosive product that can quickly damage metal tanks, some types of seals, even dispensing nozzles.

Most fuel dispensing nozzles are made from nickel plated aluminum. When Urea is dispensed through such a nozzle, the nickel plating will react changing the Diesel Emission Fluid (DEF) to where it can cause damage to the SCR (Catalytic Converter) system.

The longer the Urea is in contact with the nozzle the more potentially damaging the fluid will become. What this means is that in high volume situations, the fluid will have limited contact with the nozzle and the likelihood of fluid being contaminated is significantly reduced. In lower volume situations where there may be extended periods of time between use, there is a higher likelihood of contaminating the fluid.

It may be desirable to go to a nozzle made of unplated metal or possibly even a composite material to prevent this contamination.

It is considered vital that a non-fuel nozzle be used to prevent the possibility of accidentally adding diesel to the DEF or DEF to the Diesel Fuel. Either mistake will likely cause rapid and catastrophic failure of the engine and or the SCR System.

In Europe a company called ElaFlex provides the defacto standard for AdBlue (Urea) nozzles that have a unique feature that prevents the AdBlue (Urea) from being added to the fuel tank.

ElaFlex has recently signed an agreement with OPW to provide these nozzles to the US and Canadian markets.

We will be providing a comprehensive list of suggestions on how to safely and cost effectively dispense Urea for your fleet operation.

Diesel Doctor

Copyright 2009 – William Richards

Natural Gas as a Transportation Fuel – A Cautionary Note

Natural Gas as a Transportation Fuel – A Cautionary Note

Natural Gas is currently being promoted as a domestic clean, safe, and cheaper alternative to petroleum fuels.


Some thoughts for your consideration.


Natural Gas as domestic source of energy. The US currently imports approximately 16% of its natural gas. Some comes to us by pipeline and some in the form of LNG via ship. Increasing the use of natural gas to replace petroleum fuels simply shifts our imports from one product to another.


Currently the US uses approximately 22% of our natural gas to create electricity. This is a poor use of a valuable resource for a need that has many other fuel sources available. If this was replaced by wind, solar, nuclear, and a future renewable bio-source (see previous article: The Richards Cycle) you could eliminate our imports.


Natural Gas as a clean motor fuel. Compressed Natural Gas (CNG) and Liquefied Natural Gas (LNG) both reduce certain emissions however they are not as clean as some would have us believe. If you look the whole basket of emissions that come out of the exhaust on an internal combustion engine, a 2010 Selective Catalytic Reduction (SCR) Diesel engine actually is less polluting than an equivalent CNG or LNG engine.


While I believe you can safely use CNG and LNG, it requires more training and much greater diligence on the part of drivers and operators vehicles and fueling stations. It is important to remember that it can take far longer to fuel LNG and particularly CNG fueled equipment. This long fueling cycle can lead to lack of attention and added expense in fueling equipment.


Natural Gas as cheaper alternative. Many people incorrectly try to compare a gallon of diesel to a gallon of LNG or a gallon of CNG. While the price per gallon of the LNG and CNG may appear to be cheaper, you need to consider the energy in the gallon. For example a gallon of diesel contains approximately 139,000 Btu’s of energy, while a gallon of LNG contains about 73,500 Btu’s, and CNG works to about 34,750. In short it takes about 4 times the space to store an equivalent amount of CNG as compared to diesel.


The other concerns with vehicles powered by CNG or LNG are that they are far more expensive to purchase, for example a school bus built to run on CNG can be $30,000.00 to $40,000.00 more than its diesel counterpart.



Also when you purchase a vehicle powered by CNG or LNG you locked into one supplier for all fuel system and some engine components for ever. There is virtually no secondary supplier compatibility. You limit the range and usefulness of the vehicle due to limited ability to refuel that vehicle away from its domicile. Lastly, you have to be concerned about the value of those vehicles when it comes time to trade or sell them. In many cases this limited resale market can make a used vehicle worthless.


There is an important and growing place for alternative fuel vehicles and equipment. It takes visionary leaders with long term commitment and very deep pockets to make a change to this type of equipment successful.

You can get more information on this and other fuel related subjects at: http://www.lcbamarketing.com and click on Fuel School Articles.

Please comment here and share your thoughts, ideas, and suggestions.


Diesel Doctor



Copyright 2009© - William Richards

UREA use in 2009 and 2010 Diesel Vehicles

Urea Use in 2009 Light Duty and 2010 Medium and Heavy Duty Diesels

Hold on, here comes the next big change in diesel engines. Starting with the automotive market in 2009 and then with virtually all of the medium and heavy duty diesel vehicles in the 2010 model year, diesel engined vehicles will require an additional fluid to operate.

These vehicles will require an “aqueous urea solution” as defined by ISO 22241-1 using test methods described in ISO 22241-2:2006. This is a solution of 32.5% Urea in deionized water.

This Urea solution is used as part of a Selective Catalytic Reduction (SCR) system to reduce the NOx emissions of diesel fueled engines.

These systems require that a tank of the Urea solution be installed on the vehicle. The Urea is meter injected into the exhaust stream after the turbocharger where the exhaust heat will convert it to ammonia which is then used by a special type of catalytic converter to significantly reduce the formation of NOx. This system will function as long as there is Urea available.

This is a complicated system with maintenance requirements, cold weather operability issues (Urea freezes), and quality concerns.

There is a wide ranging debate on what type of driver information systems are to be required, what will happen if the system runs out of the Urea solution, and where Urea will be available.