Diesel Exhaust Fluid (DEF)
Liquefied Natural Gas (LNG)
Liquefied Petroleum Gas (LPG)
Diesel Exhaust Fluid
In the next few years you will start to see a couple of new acronyms when discussing diesel vehicle emissions. A new technology called Selective Catalytic Reduction (SCR) is one of the most cost-effective and fuel-efficient vehicle emissions control technologies available to reduce diesel engine emissions. In commercial trucking, SCR is expected to significantly reduce emissions while also delivering a (claimed) 3-5% fuel savings. SCR relies on the injection of a reducing agent into a reactor after combustion has taken place. The reducing agent reacts with nitrogen oxide (NOx) which may be present to convert the pollutants into nitrogen, water and tiny amounts of carbon dioxide (CO2). The claimed ful savings come from the manufacturer's ability to selectively tune the engine for maximum performance while not having to deal with the exhaust output until after combustion. It remains to be seen if these savings will be realized.
The reducing agent is Diesel Exhaust Fluid (DEF) which is a solution made up of 67.5% deionized water and 32.5% automotive-grade urea. It is used as a carrying agent for the ammonia needed to reduce various nitrogen oxide (NOx) emissions from vehicles into nitrogen, water and carbon dioxide (CO2). For those interested, the reaction is
DEF will be used in a commercial diesel engine at the rate of approximately 2%-6% of diesel consumption (2-6 litres of DEF for every 100 litres of diesel). DEF is not currently widely available in North America, but that is expected to change in the next few years. At first, you will start to see DEF marketed under various trade names and available in prepackaged containers (jugs, totes, drums, etc.). Eventually, we expect to see DEF becoming available through a dispenser located next to the diesel fuel dispenser.
At the time of this writing, there are no known approved DEF dispensers available in Canada or the USA. Purchasers of DEF must be aware that if a dispenser is being used there is a chance that the dispenser is not approved, and likely not appropriate, for the measurement of DEF. You must ensure yourself that the dispenser being used is approved for use with DEF or do not purchase product through the dispenser. Given the high cost of the product, significant measurement errors could prove to be expensive.
We will be adding much more to the DEF page as the product and associated technology becomes more widespread. In the meantime, visit the following links for more information:
- Cummins Engines
- Cummins DEF
- Cummins DEF usage calculator
- Detroit Diesel BlueTec
- Mack Trucks
- PACCAR Emission control
- Volvo Trucks
Motor fuel means any fuel intended for use in internal combustion engines. In same cases these fuels may also have other uses such as Hydrogen for a fuel cell. If it is a fuel burned for internal combustion for locomotion or stationary power, we will discuss it here. The obvious fuels are gasoline or petrol, diesel and propane but we will also discus emerging fuels such as bio-diesel, compressed natural gas (CNG), liquefied natural gas (LNG), Hydrogen and others. Look for the links at the top of the page to see what is currently covered. Stay tuned for even more discussions.
While we are at it, and in keeping with the philosophy of this site, we will discuss the best methods for measuring these fuels, the drawbacks and issues involved and how to address them. We will also look at related emerging liquids such as DEF which is not a fuel at all but may be considered as a mandatory additive for some newer engines.