Reductant injection in exhaust manifold

Patent metadata

Field	Value
Publication number	US-11408321-B2
Application number	US-202117361773-A
Country	US
Kind code	B2
Filing date	Jun 29, 2021
Priority date	Dec 5, 2014
Publication date	Aug 9, 2022
Grant date	Aug 9, 2022

Abstract

An aftertreatment system comprises a first passageway having a first temperature and a second passageway having a second temperature different than the first temperature. A turbine is disposed downstream from the first passageway and upstream from the second passageway. The turbine is in fluidic communication with the first passageway and the second passageway. The turbine is structured to receive an exhaust gas from the first passageway, generate energy using the exhaust gas flowing through the turbine and communicate the exhaust gas to the second passageway. The aftertreatment system also includes an insertion device structured to insert an exhaust reductant into the first passageway. A selective catalytic reduction system is configured to receive the exhaust gas from the second passageway and treat the exhaust gas. The first temperature can be higher than the second temperature.

First claim

What is claimed is:

1. An aftertreatment system, comprising:
a turbine;
a selective catalytic reduction system positioned downstream of the turbine;
an exhaust gas loop structured to receive an exhaust gas, the exhaust loop comprising:
a first branch fluidly coupled to the turbine, the first branch structured to communicate a first portion of the exhaust gas into the turbine,
a second branch structured to communicate a second portion of the exhaust gas to a part of the exhaust gas loop downstream of the turbine, the second branch bypassing the turbine so that the second portion of the exhaust gas does not flow through the turbine, the first portion of the exhaust gas and the second portion of the exhaust gas combining downstream of the turbine;
an insertion device structured to insert an exhaust reductant into the second branch; and
an exhaust valve positioned upstream of the first branch and the second branch, the exhaust valve structured to control the flow of the exhaust gas.

2. The aftertreatment system of claim 1 , wherein the first portion of the exhaust gas has a first portion first temperature upstream of the turbine and a first portion second temperature downstream of the turbine, the first portion first temperature greater than the first portion second temperature, and wherein the second portion of the exhaust gas has a second portion temperature lower than or equal to the first portion first temperature and higher than the first portion second temperature.

3. The aftertreatment system of claim 1 , wherein a mesh is positioned upstream of the turbine, the mesh structured to prevent reductant deposits from entering the turbine.

4. The aftertreatment system of claim 1 , wherein an exhaust gas recirculation system is fluidly coupled to the first branch, thereby receiving exhaust gas free of exhaust reductant therefrom.

5. The aftertreatment system of claim 1 , wherein the insertion device includes an injector structured to inject the exhaust reductant into the second branch.

6. The aftertreatment system of claim 1 , wherein the aftertreatment system is fluidly coupled to an exhaust gas recirculation system, and wherein the exhaust reductant is used as a coolant for the exhaust gas recirculation system, the exhaust reductant absorbing heat from the exhaust gas before communicating into the first passageway.

7. The aftertreatment system of claim 1 , wherein the turbine is coated with a corrosion resistant material.

8. The aftertreatment system of claim 1 , further comprising an oxidation catalyst disposed downstream of the turbine and upstream of the selective catalytic reduction system.

9. The aftertreatment system of claim 1 , further comprising a filter disposed downstream of the turbine and upstream of the selective catalytic reduction system.

10. The aftertreatment system of claim 1 , wherein the turbine comprises a twin entry asymmetric turbine.

11. A system, comprising:
an engine producing exhaust gas; and
an aftertreatment system, comprising:
a turbine;
a selective catalytic reduction system positioned downstream of the turbine;
an exhaust gas loop structured to receive the exhaust gas, the exhaust loop comprising:
a first branch fluidly coupled to the turbine, the first branch structured to communicate a first portion of the exhaust gas into the turbine,
a second branch structured to communicate a second portion of the exhaust gas to a part of the exhaust gas loop downstream of the turbine, the second branch bypassing the turbine so that the second portion of the exhaust gas does not flow through the turbine, the first portion of the exhaust gas and the second portion of the exhaust gas combining downstream of the turbine;
an insertion device structured to insert an exhaust reductant into the second branch; and
an exhaust valve positioned upstream of the first branch and the second branch, the exhaust valve structured to control the flow of the exhaust gas,

wherein the first portion of the exhaust gas has a first portion first temperature upstream of the turbine and a first portion second temperature downstream of the turbine, the first portion first temperature greater than the first portion second temperature, and wherein the second portion of the exhaust gas has a second portion temperature lower than or equal to the first portion first temperature and higher than the first portion second temperature,
wherein the exhaust loop is disposed downstream of the engine, the engine employing variable valve timing so as to produce the exhaust gas at the first portion first temperature, the first portion first temperature being sufficient for vaporizing the exhaust reductant.

12. A system, comprising:
an engine producing exhaust gas; and
an aftertreatment system, comprising:
a turbine;
a selective catalytic reduction system positioned downstream of the turbine;
an exhaust gas loop structured to receive the exhaust gas, the exhaust loop comprising:
a first branch fluidly coupled to the turbine, the first branch structured to communicate a first portion of the exhaust gas into the turbine,
a second branch structured to communicate a second portion of the exhaust gas to a part of the exhaust gas loop downstream of the turbine, the second branch bypassing the turbine so that the second portion of the exhaust gas does not flow through the turbine, the first portion of the exhaust gas and the second portion of the exhaust gas combining downstream of the turbine;
an insertion device structured to insert an exhaust reductant into the second branch; and
an exhaust valve positioned upstream of the first branch and the second branch, the exhaust valve structured to control the flow of the exhaust gas,

wherein the aftertreatment system is fluidly coupled to the engine, and wherein the exhaust reductant is used as a coolant for the engine, the exhaust reductant absorbing heat from the engine so that the exhaust reductant is heated before communicating into the first passageway.

Assignees

• Cummins Inc

Inventors

• Heichelbech John K
• Buechler John G
• Ancimer Richard J
• Yonushonis Thomas M

Classifications

• F01N9/00

  Electrical control of exhaust gas treating apparatus (monitoring or diagnostic devices for exhaust-gas treatment apparatus F01N11/00; conjoint electrical control of two or more combustion engine functions F02D43/00) · CPC title

• F01N3/208

  Control of selective catalytic reduction [SCR], e.g. by adjusting the dosing of reducing agent · CPC title

• F01N3/2892 Primary

  Exhaust flow directors or the like, e.g. upstream of catalytic device · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title