How does SCR technology work?
An SCR (Selective Catalytic Reduction) system is a system installed on diesel vehicles to reduce harmful Nitrous Oxide (NOx) emissions. It works by injecting an automotive grade urea, or Diesel Exhaust Fluid (DEF) through a specially designed catalyst, into the exhaust stream of a diesel engine.
What is SCR emission control?
Selective Catalytic Reduction (SCR) is an advanced active emissions control technology system that injects a liquid-reductant agent through a special catalyst into the exhaust stream of a diesel engine. The reductant source is usually automotive-grade urea, otherwise known as Diesel Exhaust Fluid (DEF).
What is SCR catalyst made of?
SCR catalysts are made from various porous ceramic materials used as a support, such as titanium oxide, and active catalytic components are usually either oxides of base metals (such as vanadium, molybdenum and tungsten), zeolites, or various precious metals.
Which catalyst is used in SCR?
Urea-SCR technology—using urea as the ammonia precursor—has been adapted for mobile diesel engines in both heavy- and light-duty applications….Table 3.
| Catalyst Technology | Temperature Range, °C |
|---|---|
| Vanadium (V2O5) | 300 – 450 |
| Fe-zeolite (high temperature) | 350 – 600 |
| Cu-zeolite (low temperature) | 150 – 450 |
What are the applications of SCR?
Applications. SCRs are mainly used in devices where the control of high power, possibly coupled with high voltage, is demanded. Their operation makes them suitable for use in medium- to high-voltage AC power control applications, such as lamp dimming, power regulators and motor control.
What is SCR warning light?
Selective Catalytic Reduction (SCR) System Indications
| Status | Warning sound | SCR warning light |
|---|---|---|
| Problem with SCR system (Maximum driving distance : 700 km (435 miles) or less) | Sound is activated when there is a problem Sound is activated when ignition is switched ON | Flashes |
What is the difference between DPF and SCR?
A DPF’s core can be made of a few different materials but the most common are cordierite composites. An SCR catalyst has valuable filter contents in the form of ceramic materials and precious metals.
Can you clean a SCR catalyst?
SCR catalyst systems need to be cleaned to remove contaminants and plugs. If the catalyst is not kept clean and the ammonia injection system is not tuned, ammonia slip occurs.
What is SCR inducement?
“Inducement” is an Environmental Protection Agency (EPA) term aimed at. keeping engines which utilize Selective Catalytic Reduction (SCR) aftertreatment. operating properly. An ‘inducement’ may also be referred to as an engine derate.
What are the advantages of SCR?
Advantages of SCR
- It can handle large voltages, currents and power.
- The voltage drop across conducting SCR is small. This will reduce the power dissipation in the SCR.
- Easy to turn on.
- Triggering circuits are simple.
- It can be protected with the help of a fuse.
- We can control the power delivered to the load.