Diesel exhaust fluid formulation that reduces urea deposits in exhaust systems
AssigneeDeere & Company
InventorsPonnaiyan Ayyappan, Danan Dou, Thomas Miller Harris
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Abstract
A Diesel Exhaust Fluid (DEF) that includes urea, demineralized water and between 5 and 300 ppm formaldehyde, this formulation of DEF include less than 0.6 ppm of phosphates, calcium, iron, aluminum, magnesium, sodium, and potassium, the formulation also includes less than 0.3 ppm copper, zinc, chromium, and nickel. This formulation of DEF reduces the accumulation of urea deposit in the diesel exhaust system relative to other formulation of specification grade DEF that include less formaldehyde.
Claims20
A formulation for reducing oxides of nitrogen in diesel engine exhaust, comprising:
- about 19.0 wt. % to about 40 wt. % urea;
- at least 0.0010 wt. % formaldehyde;
- and
- demineralized water.
A method for reducing an oxide of nitrogen in diesel exhaust, comprising the steps of:
- providing a Diesel Exhaust Fluid formulation, wherein the formulation includes:
- urea;
- ammonium carbamate;
- formaldehyde;
- demineralized water;
- no more than about 0.6 ppm of phosphates, calcium, iron, aluminum, magnesium, sodium, and potassium;
- and
- no more than 0.3 ppm copper, zinc, chromium and nickel, wherein said formulation is suitable for use in the Selective Catalytic Reduction of NOx in diesel engine exhaust gases;
- and
- introducing the formulation into diesel exhaust such that the formulation reacts with NOx on the surface of a SCR.
The method according to claim 14, wherein the determining step includes measuring the amount of urea in said formulation.
A system for reducing the level of NOx released into the atmosphere by the combustion of diesel fuel;
- comprising
- a formulation, wherein said formulation includes:
- urea;
- ammonium carbamate;
- formaldehyde;
- and
- demineralized water;
- wherein said formulation is suitable for the Selective Catalytic Reduction of NOx in diesel exhaust gases;
- and
- a reservoir for holding at one component of said formulation.
Dependencies are inferred from the claim text.