What is a SCR stand for?

Silicon Controlled Rectifier
A.

What is the SCR system?

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).
  • How do they make def fluid?

    Diesel exhaust fluid (DEF) is an aqueous urea solution made with 32.5% urea and 67.5% deionized water.
  • What is the medical term for SCR?

    Acute kidney injury (AKI) is a common and devastating medical condition, but no widely accepted definition exists. A recent classification system by the Acute Dialysis Quality Initiative (RIFLE) defines AKI largely by percentage increases in serum creatinine (SCr) over baseline.
  • What cars use adblue in UK?

    It won't be obviously advertised, but manufacturers like Volkswagen, Audi, Mercedes, Peugeot, Citroen and Jaguar all feature AdBlue technology. Most give a clue in the name – Peugeot and Citroen's BlueHDi engines feature it, while Volkswagen includes the initials SCR in the name of some of its diesel cars.
B.

What is the application 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 a chopper circuit?

    In electronics, a chopper circuit is used to refer to numerous types of electronic switching devices and circuits used in power control and signal applications. A chopper is a device that converts fixed DC input to a variable DC output voltage directly.
  • What is the use of a thyristor?

    A thyristor is a four-layer semiconductor device, consisting of alternating P type and N type materials (PNPN). The four layers act as bistable switches. As long as the voltage across the device has not reversed (that is, they are forward biased), thyristors continue to conduct electric current.
  • What is the holding voltage?

    The term holding current may refer to: Holding voltage (physiology), in electrophysiology, specifically while voltage clamping a cell, the holding current is the current that is passed into the cell in order to hold it at the command potential.
C.

How does SCR technology work?

It is called "selective" because it reduces levels of NOx using ammonia as a reductant within a catalyst system. The chemical reaction is known as "reduction" where the DEF is the reducing agent that reacts with NOx to convert the pollutants into nitrogen, water and tiny amounts of CO2.
  • What is a SCR in a power plant?

    In general, the SCR unit is located between the furnace economizer and the air heater, and the ammonia is injected into the catalyst chamber through an ammonia injection grid. As in other SCR applications, the temperature of operation is critical. Ammonia slip is also an issue with SCR technology used in power plants.
  • What cars use adblue in UK?

    It won't be obviously advertised, but manufacturers like Volkswagen, Audi, Mercedes, Peugeot, Citroen and Jaguar all feature AdBlue technology. Most give a clue in the name – Peugeot and Citroen's BlueHDi engines feature it, while Volkswagen includes the initials SCR in the name of some of its diesel cars.
  • How does ammonia reduce NOX?

    The SCR process chemically reduces the NOx molecule into molecular nitrogen and water vapor. A nitrogen based reagent such as ammonia or urea is injected into the ductwork, downstream of the combustion unit.

Updated: 12th November 2019

Rate This Answer

4 / 5 based on 1 vote.