Cairns Diesel Service offer AdBlue solutions adjustment solutions on your Agricultural equipment AdBlue is used in diesel engines to reduce nitrogen oxide (NOx) emissions, which is also known as selective catalytic reduction (SCR). However, it is expensive to maintain and many drivers choose to disable it to save money. AdBlue is injected into the exhaust gas stream to convert NOx into harmless water and nitrogen. But, the SCR system is also costly to operate and maintain mechanically.