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  • Writer's pictureOlivia

Why Are Diesel Exhaust Fluid Essential in Diesel Engines

Fleet managers, long-haul truckers, and diesel truck enthusiasts all collectively had a "Chicken Little" moment in 2010 when the Environmental Protection Agency (EPA) enforced the use of selective catalytic reduction in diesel engines. Why? Diesel car owners must supply diesel exhaust fluid, a consumable fluid, to their vehicles in order for SCR to operate correctly. Nobody likes being forced to spend extra money on a hassle.

Pollutants from diesel engines may affect both people and the environment. In order to lessen adverse impacts, international standards mandate extremely effective exhaust after-treatment systems. AdBlue® is the common trade name for diesel exhaust fluid (DEF), which is used in the after-treatment process to break down dangerous pollutants. You now have all the details you require regarding DEF, including an explanation of what it is, why you require it, and how to use it.

What is Diesel Exhaust Fluid?

NOx emissions, which are damaging pollutants, are converted into nitrogen and water by diesel exhaust fluid (DEF), a solution of urea and water that is poured into the exhaust stream of diesel vehicles. Automobile manufacturers used the Selective Catalytic Reduction (SCR) method in 2010 to comply with EPA emissions regulations. In this approach, the standards can be met without sacrificing engine performance or fuel economy. DEF is kept in separate tanks because it is not a gasoline additive.

Despite the EPA only recently starting to require targeted catalyst reduction, the technology is not new. It has been in use for over 50 years and was initially used to lower nitrogen oxide emissions from coal-fired power plants.

Never underestimate the importance of nitrogen oxides since they are the main compounds that interfere with diesel combustion and have had a big detrimental impact on the automotive industry. These chemicals include nitrogen monoxide and nitrogen dioxide.

When diesel exhaust fluid, also known as DEF or AUS 32, is added to the diesel exhaust stream, the heat from the exhaust, the fluid, and a catalyst work together to convert the NOx into harmless gases.

Diesel exhaust fluid is a distilled water solution of 32.5% technically pure urea. For the SCR unit to work properly, the DEF must adhere to certain purity standards. This ISO standard aims to ensure that the diesel exhaust fluid used in vehicles with SCR satisfies the requirements for quality and purity set forth by diesel engine producers in order to safeguard the environment and the emissions control system.

The API Diesel Exhaust Fluid (DEF) Certification Program is a voluntary program designed to confirm and monitor the quality aspects of diesel exhaust fluid approved for use in motor vehicles with diesel engines. Marketers of diesel exhaust fluid may be permitted to use the API Diesel Exhaust Fluid Certification Mark if they can demonstrate that their products meet the requirements of the most current edition of ISO 22241 that is currently available.

How does DEF work?

The exhaust stream from a vehicle with an SCR must first pass through a particle filter to fully capture all soot and ash produced by utilizing relatively dirty gasoline. As a result, the "rolling coal" issue with antique diesel engines is resolved, which removes the reason why they were despised in the US during the 1960s, 1970s, and 1980s. As the exhaust gas passes a nozzle that exits the particle filter, diesel exhaust fluid is injected into the gaseous stream. Deionized water and an incredibly pure type of urea are used to make DEF. The substance, which is mostly used in fertilizer in the agricultural sector, is now accessible in a more refined form.

Heated exhaust gas and DEF are carried to the catalytic converter after entering the engine. There, urea in the DEF reacts with the exhaust gas and various metallic components to produce nitrogen and water from nitrogen dioxide and monoxide. The main element of the air we breathe, nitrogen, is harmless for the ecosystem. The element of water itself is everything.

Diesel Affecting Human Health

Diesel fuel has various hazards despite its benefits. Diesel fuel exhaust contains nitric oxide and nitrogen dioxide (together known as NOx). NOx is dangerous to humans even at relatively low concentrations when inhaled. According to the International Agency for Research on Cancer, it is far more dangerous than gasoline (petrol) emissions, which are categorized as a Category 2B or "possible" cause of cancer.

Diesel exhaust contains a group of compounds known as polycyclic aromatic hydrocarbons (PAH), which damage DNA and raise the risk of cancer. Pulmonary inflammation and cell changes brought on by particles can result in the development of lung cancer. Some drugs have also been linked to bladder cancer.

How Much DEF Do You Need?

Two to ten percent of all fuel is consumed by diesel vehicles. A technology known as exhaust gas recirculation is frequently used with DEF (EGR). EGR and DEF have an inverse relationship; the more EGR an engine uses, the less DEF it requires.

The climate in which a vehicle works has some bearing on whether it needs DEF. Your car need less DEF if you live in a humid or cool region than if you do in a dry or hot one. The good news is that DEF is increasingly becoming a standard and is frequently supplied at the pump at most gas stations and truck stops. You can buy enough fuel to supply all of the diesel vehicles in your fleet.

The vehicle's speed will decrease if you run out of DEF before recharging. If you don't finish your drinks, they won't go back to normal. if your car was created by hand

To Sum it Up

An oil change for a car is comparable to replacing your diesel exhaust fluid. If you keep it running for too long, your engine can suffer permanent harm. Keep an eye on your DEF levels, make sure you top them off often and take pleasure in the knowledge that you're contributing to environmental protection.

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