FORM 2
THE PATENT ACT 1970
(39 of 1970)
AND
THE PATENT RULES, 2005
COMPLETE SPECIFICATION (SEE SECTION 10 AND RULE 13)
TITLE OF THE INVENTION
EMISSION TREATMENT SYSTEM FOR TREATING AN EXHAUST STREAM FROM AN ENGINE
APPLICANTS
TATA MOTORS LIMITED
an Indian company having its registered office
at Bombay house, 24 Homi Mody Street,
Hutatma Chowk, Mumbai 400 001,
Maharashtra, India.
and
TATA MOTORS EUROPEAN TECHNICAL CENTRE Plc
an United Kingdom company
18 Grosvenor Place, London, SW1X 7HS, London
United Kingdom
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
[0001] The present disclosure relates to an emission treatment system and, more particularly, to the emission treatment system for treating an exhaust stream from an engine.
BACKGROUND OF THE INVENTION
[0002] Diesel engine, petrol engine, and hydrogen engine exhaust is a heterogeneous mixture, which contains not only gaseous emissions such as carbon monoxide (“CO”), unburned hydrocarbons (“HC”) and nitrogen oxides (“NOx”), but also condensed phase materials (liquids and solids), which constitute the so-called particulates or particulate matter. Often, catalyst compositions and substrates on which the compositions are disposed, are provided in diesel, petrol or hydrogen engine exhaust systems to convert certain or all of these exhaust components to innocuous components. For example, diesel exhaust systems can contain one or more of a diesel oxidation catalyst, a soot filter and a catalyst for the reduction of NOx. FIG. 1 illustrates a conventional diesel engine, according to prior art. The current diesel treatment systems involves adding Urea to a tank, which is added to an exhaust stream in a controlled dose. There is anecdotal evidence to suggest that end users are replacing the urea with alternative cheaper or free liquids to prevent the dosage system from forcing the vehicle into a “limp” maintenance mode, but the addition of the alternative liquids renders the treatment chemistry useless. Treatment of emission gas exhaust from diesel engines and achieving the diesel particulate and the NOX gas emission regulations imposes an ever-increasing cost to the vehicle manufacturer and the vehicle owner due to addition of complex after treatment technologies and costly additives. There is an ongoing need to

investigate and provide alternative system strategies to improve the treatment of exhaust gas streams containing NOx and particulate matter.
OBJECT OF THE INVENTION
[0003] The principal object of the embodiments herein is to provide emission treatment system for treating an exhaust stream from an engine.
[0004] Another object of the embodiments herein to provide the electrostatic precipitator for capturing soot particles from exhaust stream of the diesel engine using a principle of electrostatic precipitation.
[0005] Another object of the embodiments herein to provide titanium oxide catalyst for converting nitrogen oxide gas into nitrogen and oxygen.
SUMMARY
[0006] In one aspect, an object is satisfied by providing an emission treatment system for treating an exhaust stream from a diesel engine. The emission treatment system comprises an electrostatic precipitator connected to a titanium oxide catalyst. The electrostatic precipitator captures soot particles from exhaust stream of the diesel engine using a principle of electrostatic precipitation. The titanium oxide catalyst converts nitrogen oxide gas into nitrogen and oxygen.
[0007] In an embodiment, the electrostatic precipitator comprises a negatively charged metal plate and a positively charged collecting plate. The negatively charged metal plate charges the soot particles negatively using a voltage ionization array. The positively charged collecting plate charges the

soot particles positively by passing the negatively charged soot particles through a positively charge array.
[0008] In an embodiment, the negatively charged metal plate of the electrostatic precipitator is connected to an output terminal of an ignition coil and the positively charged collecting plate is connected to a primary terminal of the ignition coil.
[0009] In an embodiment, the titanium oxide catalyst comprises a light source and a titanium oxide coated layer. The light source illuminates an exhaust gas through a titanium oxide coated layer to convert the nitrogen oxide gas into the nitrogen and the oxygen.
[0010] In an embodiment, the titanium oxide catalyst converts the nitrogen oxide gas into the nitrogen and the oxygen without using fuel.
[0011] In an embodiment, the captured soot particles are recycled without using fuel or thermal regeneration.
[0012] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF FIGURES
[0013] This emission treatment system is illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0014] FIG. 1 illustrates a conventional diesel engine, according to prior art;
[0015] FIG. 2 illustrates an emission treatment system for a diesel engine, according to an embodiment as disclosed herein;
[0016] FIG. 3 illustrates working of electrostatic precipitator, according to an embodiment as disclosed herein;
[0017] FIG. 4 illustrates working of titanium oxide catalyst, according to an embodiment as disclosed herein;
[0018] FIG. 5a illustrates an example of titanium oxide coated glass beads, according to an embodiment as disclosed herein; and
[0019] FIG. 5b illustrates an example of titanium oxide coated glass beads on a vehicle, according to an embodiment as disclosed herein.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The embodiments herein, the various features, and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. Also, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments. The term “or” as

used herein, refers to a non-exclusive or, unless otherwise indicated. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein can be practiced and to further enable those skilled in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0021] The accompanying drawings are used to help easily understand various technical features and it should be understood that the embodiments presented herein are not limited by the accompanying drawings. As such, the present disclosure should be construed to extend to any alterations, equivalents and substitutes in addition to those, which are particularly set out in the accompanying drawings. Although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are generally only used to distinguish one element from another.
[0022] Referring now to the drawings, and more particularly to FIGS. 2 through 5, there are shown preferred embodiments.
[0023] FIG. 2 illustrates an emission treatment system (1000) for a diesel engine, according to an embodiment as disclosed herein. However, this invention is not limited to the diesel engine. The petrol engine and hydrogen engine also produce NOX and the present invention is equally applicable for both petrol and hydrogen engine to improve the treatment of exhaust gas streams containing NOx and particulate matter. The emission treatment system (1000) comprises an electrostatic precipitator (100) and titanium oxide catalyst (200). The electrostatic precipitator (100) captures soot particles from exhaust stream of the diesel engine using a principle of electrostatic precipitation. The titanium oxide catalyst (200)

converts nitrogen oxide gas into nitrogen and oxygen. Unlike conventional diesel engine, the proposed emission treatment system (1000) treats the exhaust of a diesel engine in two stages using the principle of electrostatic precipitation for capturing soot particles and photo catalysis using titanium oxide for converting the nitrogen oxide gas into the nitrogen and the oxygen.
[0024] In an embodiment, the titanium oxide catalyst (200) converts the nitrogen oxide gas into the nitrogen and the oxygen without using fuel.
[0025] In an embodiment, the captured soot particles are recycled without using fuel or thermal regeneration.
[0026] FIG. 3 illustrates working of an electrostatic precipitator (100), connected to a conventional ignition coil (300), according to an embodiment as disclosed herein. In an embodiment, the electrostatic precipitator (100) comprises a negatively charged metal plate (101) connected to a positively charged collecting plate (102). The negatively charged metal plate (101) charges the soot particles negatively using a voltage ionization array. The positively charged collecting plate (102) charges the soot particles positively by passing the negatively charged soot particles through a positively charge array.
[0027] Further, the ignition coil (300) comprises an output terminal (301), a primary terminal (302), a primary coil (303), a secondary coil (304), and an iron core (305). The negatively charged metal plate (101) of the electrostatic precipitator (100) is connected to an output terminal (301) of the ignition coil (300) and the positively charged collecting plate (102) is connected to a primary terminal (302) of the ignition coil (300).

[0028] FIG. 4 illustrates working of the titanium oxide catalyst (200), according to an embodiment as disclosed herein. The titanium oxide catalyst (200) comprises a light source (201) and a titanium oxide coated layer (202). The light source (201) illuminates an exhaust gas through a titanium oxide coated layer (202) to convert the nitrogen oxide gas into the nitrogen and the oxygen. Unlike the conventional diesel system, the photocatalytic breakdown of the nitrogen oxide using the titanium oxide works at any temperature and does not require any fuel.
[0029] FIG. 5a illustrates an example of titanium oxide coated glass beads and FIG. 5b illustrates an example of titanium oxide coated glass beads on vehicle, according to an embodiment as disclosed herein. A bench experiment consisting of a test tube filled with spherical glass beads coated in a thin but transparent layer of titanium oxide is illustrated in FIG. 5a. When the NOX gas was passed over the beads, say from left to right, ambient light is used to convert the NOX into N + O. Further, FIG. 5b shows a possible scaled-up version of the bench experiment with titanium coated glass beads held in a canister (which does not need to be transparent and will likely be a steel fabrication). The canister is inline to the exhaust gas stream and NOX enters from the engine side. The NOX passes over the glass beads and light is introduced into the canister. The light is refracted through the canister by passing through the thin titanium oxide layer through the glass beads and into the adjacent bead. This treats any NOX in the interspaces between the beads before the separate N + O gasses are exhausted to the atmosphere. Although the glass beads are used and illustrated in FIG. 5a as it is easy to produce, it is to be noted that the proposed invention is not limited to glass beads. A person ordinary skilled in the art may appreciate that other glass or component in a different form, in which an increased surface area is deemed necessary, can be used.

[0030] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

We Claim:
1. An emission treatment system (1000) for treating an exhaust stream
from an engine, the system (1000) comprising:
an electrostatic precipitator (100) for capturing soot particles from exhaust stream of the engine using a principle of electrostatic precipitation; and
an titanium oxide catalyst (200) for converting nitrogen oxide gas into nitrogen and oxygen.
2. The emission treatment system (1000) as claimed in claim 1, wherein
the electrostatic precipitator (100) comprises:
a negatively charged metal plate (101) for negatively charging the soot particles using a voltage ionization array; and
a positively charged collecting plate (102) for positively charging the soot particles by passing the negatively charged soot particles through a positively charge array.
3. The emission treatment system (1000) as claimed in claim 2, wherein the negatively charged metal plate (101) of the electrostatic precipitator (100) is connected to an output terminal (301) of an ignition coil (300) and the positively charged collecting plate (102) is connected to a primary terminal (302) of the ignition coil (300).
4. The emission treatment system (1000) as claimed in the claim 1, wherein the titanium oxide catalyst (200) comprises:
a light source (201); and

a titanium oxide coated layer (202), wherein the light source (201) illuminates an exhaust gas through a titanium oxide coated layer (202) to convert the nitrogen oxide gas into the nitrogen and the oxygen.
5. The emission treatment system (1000) as claimed in the claim 1, wherein the titanium oxide catalyst (200) converts the nitrogen oxide gas into the nitrogen and the oxygen without using fuel.
6. The emission treatment system (1000) as claimed in the claim 1, wherein a titanium oxide coated glass beads is used for converting the nitrogen oxide gas into the nitrogen and the oxygen.
7. The emission treatment system (1000) as claimed in the claim 1, wherein the captured soot particles are recycled without using fuel or thermal regeneration.
8. The emission treatment system (1000) as claimed in claim 1, said engine is selected from diesel engine, petrol engine, and hydrogen engine.