×

Urea pyrolysis chamber and process for reducing lean-burn engine NOx emissions by selective catalytic reduction

  • US 6,203,770 B1
  • Filed: 08/20/1999
  • Issued: 03/20/2001
  • Est. Priority Date: 05/12/1997
  • Status: Expired due to Term
First Claim
Patent Images

1. An apparatus for reducing the emissions of Nox from a lean-burn engine having associated therewith an exhaust system having an exhaust passage leading to a SCR reactor effective for selective catalytic Nox reduction, comprising:

  • a pyrolysis chamber for pyrolizing urea fed as an aqueous solution including heated internal surfaces and having openings therein to permit discharge of gases generated by pyrolysis of urea and vaporization of water;

    means for passing the gases generated by pyrolysis into the exhaust passage containing exhaust gases;

    means for passing the exhaust gases containing the gases generated by pyrolysis to a SCR reactor;

    spray means capable of spraying the urea solution into the pyrolysis chamber; and

    said spray means comprising an injector nozzle having associated lines for feeding the solution to the nozzle and returning solution not discharged from the nozzle.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×