Heating system for an exhaust gas treatment system

Patent metadata

Field	Value
Publication number	US-10082065-B2
Application number	US-201515115822-A
Country	US
Kind code	B2
Filing date	Jan 20, 2015
Priority date	Feb 6, 2014
Publication date	Sep 25, 2018
Grant date	Sep 25, 2018

Abstract

The present disclosure relates to a heating system for an exhaust gas treatment system. The heating system comprises a first heating element comprising a receiving surface for receiving a reductant fluid and a second heating element, which may surround the first heating element. The second heating element may be a thermochemincal or thermophysical device. In a first mode of operation the second heating element is arranged to receive thermal energy from engine exhaust gas. In second mode of operation the second heating element transfers thermal energy to heat the first heating element.

First claim

The invention claimed is:

1. A heating system for an exhaust gas treatment system, comprising:
a first heating element comprising a plurality of flow passages and a receiving surface for receiving a reductant fluid; and
a second heating element;
wherein in a first mode of operation the second heating element is arranged to receive thermal energy from engine exhaust gas and, in a second mode of operation, transfer thermal energy to heat the first heating element.

2. The heating system as claimed in claim 1 in which the first heating element is at least partially surrounded by and in contact with at least a part of the second heating element.

3. The heating system as claimed in claim 1 in which the second heating element is a device which utilises thermal energy from exhaust gas to effect a thermochemical or a thermophysical process.

4. The heating system as claimed in claim 3 which the second heating element is a heat pump or a heat battery.

5. The heating system as claimed in claim 4 which the second heating element is a heat pump comprising a reactor vessel and a condenser vessel fluidly linked by a connecting pipe and a valve operable to open and close the connecting pipe.

6. The heating system as claimed in claim 1 in which the reductant fluid is urea or a urea composition.

7. An engine comprising:
an exhaust gas treatment system configured to receive exhaust gas produced during operation of the engine, said exhaust gas treatment system comprising a reductant fluid injector and a catalyst located downstream of the reductant fluid injector;
an exhaust passage;
a heating system located downstream of the reductant fluid injector and upstream of the catalyst; the heating system comprising:
a first heating element having a plurality of flow passages and a receiving surface for receiving a reductant fluid; and
a second heating element;
wherein in a first mode of operation the second heating element is arranged to receive thermal energy from engine exhaust gas and, in a second mode of operation, transfer thermal energy to heat the first heating element; and

an exhaust gas feedback passage fluidly coupled between the exhaust passage and the second heating element to convey a portion of exhaust gas to the second heating element.

8. The engine as claimed in claim 7 which the exhaust gas feedback passage is fluidly coupled to the exhaust passage downstream of the exhaust gas treatment system.

9. A method of heating a reductant fluid in an exhaust gas treatment system of an engine, comprising the steps of:
in a first mode of operation, transferring thermal energy from exhaust gas to a second heating element; and
in a second mode of operation, transferring thermal energy from the second heating element to a first heating element, the first heating element comprising a receiving surface for receiving the reductant fluid.

10. The method as claimed in claim 9 in which thermal energy from the exhaust gas is used to effect a thermochemical or a thermophysical process in the second heating element.

11. The method as claimed in claim 10 in which, in the first mode of operation, the exhaust gas is used to effect a thermochemical process comprising the steps of evaporating a working fluid from an adsorbent in a first vessel in an endothermic reaction, passing the vapour to a second vessel having a fluid connection with the first vessel, condensing the vapour and closing the fluid connection between the vessels, wherein a partial vacuum is formed in the first vessel.

12. The method as claimed in claim 10 in which, in the second mode of operation, the fluid connection between the vessels is opened and the working fluid in the second vessel evaporates and passes into the first vessel in which it is exothermically adsorbed by the adsorbent, thereby releasing heat and heating the first heating element.

13. The method as claimed in claim 12 wherein, in the second mode of operation, reductant fluid is introduced onto the first heating element, whereby it is heated to a temperature at which the reductant fluid decomposes.

14. The method as claimed in claim 9 , in which the reductant fluid is urea or a urea composition and the first heating element is heated by the second heating element to at least 180° C.

Assignees

• Perkins Engines Co Ltd

Inventors

• Silver Ronald
• Moore Paul
• Strashny Igor
• Heaton David

Classifications

• Y02T10/24

  Cross-Sectional Technologies · mapped topic

• F01N3/208

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

• F01N5/02 Primary

  the devices using heat · CPC title

• F01N3/2066 Primary

  Selective catalytic reduction [SCR] · CPC title

• F01N2610/102

  after addition to exhaust gases, e.g. by a passively or actively heated surface in the exhaust conduit · CPC title