Volvo VN, Руководство оператора

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Volvo, US10 Emissions Solution 347
Exhaust Aftertreatment System Components
and Operation
Selective Catalytic Reduction (SCR)
Selective Catalytic Reduction (SCR) is an emissions-reduction technology with the
ability to deliver near-zero emissions of nitrogen oxides (NOx), a smog-causing
pollutant and greenhouse gas. SCR’s performance has been proved in millions of
miles of real-world truck operations in other countries, as well as in long-term field
tests in the U.S.
SCR reduces NOx emissions to very low levels, while at the same time delivering
excellent fuel economy and reliability. The system doesn’t change the design or
operation of the basic engine. Rather, SCR is an Aftertreatment system which
converts NOx in the exhaust stream into harmless gases. Modern diesels already use
exhaust Aftertreatment systems, called diesel particulate filters, to control emissions
of another pollutant, soot (also known as particulate matter or PM).
SCR works by injecting Diesel Exhaust Fluid (DEF) into the exhaust. DEF is a
solution of ultra- pure water and urea. DEF works with the heat of the exhaust and
a catalyst to convert NOx into nitrogen and water vapor - two harmless and natural
components of the air we breathe. The end result is cleaner air, excellent fuel
efficiency and a reliable emissions control system for today’s modern diesel engine.