company news about What is the SCR system in a car?

The SCR (Selective Catalytic Reduction) system in a car is an advanced emissions control technology designed to reduce harmful nitrogen oxides (NOx) in diesel engine exhaust. Here's a detailed breakdown:

1. ‌Core Function‌

The SCR system chemically converts NOx—a major pollutant linked to smog and health issues—into harmless nitrogen (N₂) and water (H₂O) through a reaction with urea solution (commonly marketed as AdBlue). This process occurs in the exhaust system after combustion, helping vehicles meet stringent environmental standards like Euro 6 or China’s National VI‌.

2. ‌Key Components‌
Urea Injection System‌: Precisely sprays a 32.5% urea-water solution into the exhaust stream‌.
Catalytic Converter‌: Contains catalysts (e.g., vanadium or titanium) to facilitate the NOx reduction reaction‌.
Sensors & Control Unit‌: Monitors NOx levels and adjusts urea dosing for optimal efficiency‌.
3. ‌How It Works‌
Urea Decomposition‌: Injected urea breaks down into ammonia (NH₃) and carbon dioxide (CO₂) at high exhaust temperatures (200°C+)‌.
Catalytic Reaction‌: Ammonia reacts with NOx on the catalyst surface, producing N₂ and H₂O. Two primary reactions occur:
4NO + 4NH₃ + O₂ → 4N₂ + 6H₂O
NO + NO₂ + 2NH₃ → 2N₂ + 3H₂O‌.
4. ‌Advantages Over Alternatives‌
Higher Efficiency‌: SCR reduces NOx by 50–90%, outperforming EGR (Exhaust Gas Recirculation) systems‌.
Fuel Economy‌: Lower fuel consumption compared to EGR/DPF systems, as urea usage partially offsets energy demands‌.
Compliance‌: Enables diesel vehicles to meet global emission standards without major engine redesigns‌.
5. ‌Maintenance & Warnings‌
SCR Indicator Light‌: Signals issues like low urea levels or system faults. Ignoring it may reduce engine power or damage components (e.g., urea pump)‌.
Urea Quality‌: Requires specific AdBlue-grade urea to avoid crystallization or catalyst damage‌.

The SCR system is a critical technology for cleaner diesel vehicles, balancing environmental goals with operational efficiency‌.