A METHOD AND SYSTEM FOR REDUCING START EMISSIONS AND TRANSIENT FUEL IN INTERNAL COMBUSTION ENGINE
FIELD OF INVENTION:
[001] The present subject matter described herein, relates to exhaust system of the vehicle, and, in particular, to an exhaust system which re-circulate engine 5 emissions into catalytic converter of the exhaust system for further purification of the emissions. In more particularly, the present subject matter relates to an exhaust system having a pressurized transfer chamber and a plurality of electrical valves to re-direct the flow of emissions into the catalytic converter for further purification. 10
BACKGROUND AND PRIOR ART:
[002] On-road vehicles are responsible for a significant and rapidly increasing portion of the air pollution in the environment. Untreated and harmful exhaust gases/emissions from the vehicles is the major problem with automobile industry. The vehicle generates emission during cold start, hot start, and transient running 15 conditions. However, the cold start emission contributes majorly for production of harmful or unacceptable pollutants generated by internal combustion engine. The vehicle emissions contain harmful pollutants, such as unburned hydrocarbon HC, carbon monoxide (CO), carbon dioxide (CO2), nitrous oxide (NOx). During Cold/ Hot Starting, the initial fueling applied to propel the engine from stationary 20 position is very high. Further, the post combustion emission treatment systems, such as catalytic converter are not efficient during the cold start because the post combustion emission treatment systems are below their operational temperatures, and hence all the engine emissions are expelled into the environment without getting treated. These expelled emissions comprises of almost 90% of the total 25 emissions measured during vehicular operation cycle. During the cold start condition of engine, the catalytic converter is below the operational temperature, i.e., above 300o C, therefore all the emissions, for a period until catalytic converter is operational after cold engine starting, go to environment without any treatment. The catalytic converter takes time to become operational hence large part of un-30
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treated emissions goes to environment. Therefore, even though the engine exhaust is flowing through the catalytic converter, until the exhaust heats the catalytic converter to its operating range from engine start up, the exhaust flow is only slightly catalyzed during that time period.
[003] The catalytic converter is located in the exhaust system just after the 5 internal combustion engine. Generally, the catalytic converter includes a canister which holds a suitable catalyst, such as a three-way catalytic converter (TWC) catalyst monolith, that will oxygenate unburned, unacceptable components in the exhaust stream including hydrocarbons ("HC"), their partially oxidized derivatives, such as aldehydes and carbon monoxide ("CO"), and at the same time 10 reducing nitrogen oxides ("NOx"), after almost stoichiometric fuel burn with oxygen in the cylinders of the engine. The exhaust gas is passed through the catalyst monolith, thereby completing the oxygenation of unburned HC and CO, and the reduction of NOx in the exhaust to convert these unacceptable emissions into acceptable emissions. Certain unacceptable emissions in the exhaust stream, 15 including unburned hydrocarbons and carbon monoxide, require an oxidation reaction to destroy them so that they end up as the corresponding oxides, e.g. water and carbon dioxide. On the other hand, NOx requires a reduction reaction to develop N2 and O2. The O2 product of this reduction contributes to the oxidation of the HC and CO in the exhaust system. 20
[004] The catalytic converter purifies the emissions only when the temperature of the catalytic converter is above the light-off temperature, i.e., above 350o C. The time period between when the exhaust emissions begin (i.e., "cold start"), until the time when the catalytic converter heats up to work efficiently, is generally referred to as the light-off time. During the light-off time, the emissions 25 pass through the catalytic converter unchanged and pollute the environment.
[005] Therefore the major technical problem with the present exhaust system is to treat emissions during cold start, hot start and transient running conditions. Further, treatment of the emissions through catalytic converter when temperature of the catalytic converter is above the light-off temperature. 30
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[006] In order to treat the cold start emissions from the catalytic converter, several conventional methods are used to address the problem. Current techniques employ one or more of the following methods: electrical heating of the catalytic converter, and placing the catalytic converter adjacent to the engine for heating. All of these methods have drawbacks and limitations. 5
[007] Providing the catalytic converter almost immediately adjacent to the engine for capturing of emissions is not feasible because of the tendency to overheat the catalyst with resulting accelerated degradation of the catalyst due to excessive heat. Thermal insulation is also not an acceptable option because of the same problems, especially during operation under maximum operating 10 temperature ranges. Further, the major disadvantage of this system is that during cold operation ambient condition, the moisture level in the system is high, also during engine operation water is produced as a bi product of combustion. Thus when this water or after vapor come in contact with the hydrocarbon capturing bed (which comprises of charcoal, etc.) gets neutralized as it absorbs all the 15 moisture and water in its surroundings and hence is not able to capture and store hydrocarbons during cold operation.
[008] Providing a heater inside the catalytic converters in order to heat and bring the catalyst at light off temperature to convention the engine emissions into more acceptable emissions, such as carbon dioxide (CO2). The primary limitation on 20 electrical preheating is the electrical energy required by the heater. The typical car battery is not a practical power source to supply the electrical power because the electrical load on the vehicle battery during the period required may exceed the rated battery output. In any event, the load placed on a typical 12 volt vehicle battery will shorten the lifetime of the battery. Also, there is a measurable delay 25 between the time the operator of the vehicle places the ignition switch in the "on" position and the time the heater brings the catalyst to light-off temperature. Further the heater unit placed inside the catalytic converter cannot withstand with the temperature attained by the catalyst during operating temperature and its wire and jacket disoriented and malfunctions. 30
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[009] Till date, there has not been any exhaust system which efficiently treats the cold start emissions with the conventional catalytic converter without the inherent drawbacks stated above. In view of the above, it is beneficial to have an exhaust system that reduces the cold start, hot start and transient condition emissions and treat the emissions again by the catalytic converter for improving the acceptability 5 of emission pollutants. Therefore, there is a need in the art to provide an exhaust system that is more simple and inexpensive, and which can be placed in the exhaust system of vehicle to reduce the cold start and hot start emissions effectively without incorporating any other electrical or purifier device for treatment of emissions. 10
OBJECTS OF THE INVENTION:
[0010] The principal object of the present invention is to provide an exhaust system for treating emissions of internal combustion engine and converting the emissions into acceptable form.
[0011] Another object of the present subject matter is to provide a pressurized 15 transfer chamber in the exhaust system for capturing the emissions during cold start condition of the internal combustion engine.
[0012] Another object of the present subject matter is to provide a pressurized transfer chamber which opens above the catalytic converter to release the captured emissions for treatment of captured emission through catalytic converter. 20
[0013] Another object of the present subject matter is to provide a secondary exhaust pipe to capture emissions during sudden acceleration of engine and releasing the captured emission in the catalytic converter for converting the emissions into acceptable form.
[0014] Another object of the present invention is to reduce Hydrocarbons, NOx 25 and Carbon monoxide from the engine emissions.
[0015] Another object of the present invention is to provide a plurality of electrical valves that are coupled with the electronic control unit for opening and closing.
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[0016] Yet another object of the present invention is to reduce NOx generation in the catalytic converter without any extra fuel injection.
[0017] Yet another object of the present invention is to provide a simple and inexpensive exhaust system for reducing emission during cold and hot start condition of engine and sudden acceleration condition of engine. 5
SUMMARY OF THE INVENTION:
[0018] The subject matter disclosed herein relates to an exhaust system for reducing engine emissions during cold and hot start of the engine. The present exhaust system converts unacceptable emissions pollutant, such as hydrocarbon, carbon monoxide, and nitrous oxide (NOx) into acceptable emission pollutants, 10 such as CO2 before releasing in environment. The exhaust system has a main exhaust pipe connected with exhaust of engine cylinders in the engine compartment at the front side of vehicle to receive the emissions/exhaust gases and release the emissions in the environment from rear ride of the vehicle. The exhaust system has a catalytic converter which is provided in the exhaust pipe 15 after the engine to treat and convert the non-acceptable pollutants into acceptable pollutants. Further, the exhaust system has a pressurized transfer chamber which is provided after the catalytic converter in the main exhaust pipe to receive the emissions. One end of the pressurized transfer chamber is connected with the main exhaust pipe with a Tee connection after the catalytic converter. Where other 20 end of the pressurized transfer chamber is provided above the catalytic converter for releasing the captured emissions in the catalytic converter for treatment. The pressurized transfer chamber has one electrical valve at both the ends. Further, the exhaust system has a plurality of electrical valves at different location in the main exhaust pipe to recirculate the emissions in the catalytic converter for further 25 purification. The plurality of electrical valves is controlled by Electronic Control Unit of the vehicle. During the cold and hot start condition, the electrical valve at the tee connection of the pressurized transfer chamber opens to trap the emission of the engine in the pressurized transfer chamber. Once the emissions are captured inside the pressurized transfer chamber, the electrical valve at the tee connection 30
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and at the releasing end of the pressurized transfer chamber is closed. Capturing of emissions after the catalytic converter helps to raise the operating temperature of the catalytic converter. When the engine is running at a steady state and operating temperature of the catalytic converter is above light-off temperature, the ECU opens the electrical valve available at the releasing end of the pressurized 5 transfer chamber to release the captured emissions slowly in the catalytic converter for conversion of unacceptable pollutants into acceptable pollutants.
[0019] Further, the present exhaust system has a secondary exhaust pipe which directs the emissions generated during sudden acceleration condition of engine to the catalytic converter. An electrical valve available at end of the exhaust main 10 pipe is closed by the ECU upon getting sudden acceleration inputs and directs flow of the emissions into the secondary exhaust pipe. The secondary exhaust pipe releases the redirected emissions in to the catalytic converter to avoid production of NOx.
[0020] In order to further understand the characteristics and technical contents of 15 the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit scope of the present subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] It is to be noted, however, that the appended drawings illustrate only 20 typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same 25 numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
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[0022] Fig. 1a and 1b illustrate an exhaust system for reducing engine emissions, in accordance with an embodiment of the present subject matter.
[0023] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and 5 methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0024] The subject matter disclosed herein relates to an exhaust system for reducing engine emissions during cold and hot start of the engine. The present 10 exhaust system converts unacceptable emissions pollutant, such as hydrocarbon, carbon monoxide, and nitrous oxide (NOx) into acceptable emission pollutants, such as CO2 before releasing in environment. The exhaust system has a main exhaust pipe connected with exhaust of engine cylinders in the engine compartment at the front side of vehicle to receive the emissions/exhaust gases 15 and release the emissions in the environment from rear ride of the vehicle. The exhaust system has a catalytic converter which is provided in the exhaust pipe after the engine to treat and convert the non-acceptable pollutants into acceptable pollutants. Further, the exhaust system has a pressurized transfer chamber which is provided after the catalytic converter in the main exhaust pipe to receive the 20 emissions. One end of the pressurized transfer chamber is connected with the main exhaust pipe with a Tee connection after the catalytic converter. Where other end of the pressurized transfer chamber is provided above the catalytic converter for releasing the captured emissions in the catalytic converter for treatment. The pressurized transfer chamber has one electrical valve at both the ends. Further, the 25 exhaust system has a plurality of electrical valves at different location in the main exhaust pipe to recirculate the emissions in the catalytic converter for further purification. The plurality of electrical valves is controlled by Electronic Control Unit of the vehicle. During the cold and hot start condition, the electrical valve at the tee connection of the pressurized transfer chamber opens to trap the emission 30
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of the engine in the pressurized transfer chamber. Once the emissions are captured inside the pressurized transfer chamber, the electrical valve at the tee connection and at the releasing end of the pressurized transfer chamber is closed. Capturing of emissions after the catalytic converter helps to raise the operating temperature of the catalytic converter. When the engine is running at a steady state and 5 operating temperature of the catalytic converter is above light-off temperature, the ECU opens the electrical valve available at the releasing end of the pressurized transfer chamber to release the captured emissions slowly in the catalytic converter for conversion of unacceptable pollutants into acceptable pollutants.
[0025] Further, the present exhaust system has a secondary exhaust pipe which 10 directs the emissions generated during sudden acceleration condition of engine to the catalytic converter. A electrical valve available at end of the exhaust main pipe is closed by the ECU upon getting sudden acceleration inputs and directs flow of the emissions into the secondary exhaust pipe. The secondary exhaust pipe releases the redirected emissions in to the catalytic converter to avoid production 15 of NOx.
[0026] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the 20 same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to 25 aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. The novel features which are believed to be characteristic of the present subject matter, both as to its organization and method of operation, 30
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together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures.
[0027] These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be 5 noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0028] Fig. 1a and 1b illustrate exhaust system for reducing emissions in vehicle, 10 in accordance with the present subject matter. The exhaust system 100 has a main exhaust pipe 9, a pressurized transfer chamber 1, a secondary exhaust pipe 2, and a catalytic converter 10. Further, the exhaust system 100 has a plurality of electrical valves 3, 4, 5, 6, 7. The plurality of electrical valves 3, 4, 5, 6, 7 is butterfly valves. The plurality of electrical valves 3, 4, 5, 6, 7 is controlled by 15 Electronic Control Unit (ECU) of the vehicle. Further, the plurality of electrical valves 3, 4, 5, 6, 7 are present at different location in the main exhaust pipe 9 to re-circulate the emissions in the catalytic converter 10 for further purification. The main exhaust pipe 9 is connected with exhaust of engine cylinders in the engine compartment at the front side of vehicle to receive the emissions/exhaust gases 20 and release the emissions in the environment from rear ride of the vehicle. The catalytic converter 10 is provided in the main exhaust pipe 9 after the engine to treat and convert the non-acceptable pollutants, such as hydrocarbon, carbon monoxide, and NOx into acceptable pollutants, such as carbon dioxide and H2. In the exhaust system 100, the pressurized transfer chamber 1 is provided after the 25 catalytic converter 10 in the main exhaust pipe 9 to receive the emissions passed by the catalytic converter 10. During the cold start condition, the emissions produce by the engine passes through the catalytic converter 10 and remain un-converted. However these emissions provide some heat to the catalytic converter 10 for raising the operating temperature of the catalytic converter 10 which helps 30
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in converting process. Similarly, during the hot start condition, the emissions passes through the catalytic converter 10 heats up the catalytic converter for better conversion.
[0029] One end of the pressurized transfer chamber 1 is connected with the main exhaust pipe 9 with a Tee connection after the catalytic converter 10. Where other 5 end of the pressurized transfer chamber 1 is provided above the catalytic converter 10 for releasing the captured emissions in the catalytic converter 10 for further treatment. The pressurized transfer chamber 1 has one electrical valve 7 at the tee connection and other electrical valve 3 at the connection of the other end of the pressurized transfer chamber 1 which is just above the catalytic converter 10. Both 10 the electrical valves 3 and 7 are controlled by the ECU. During cold and hot start condition of the internal combustion engine the ECU judges the time required for the exhaust gas to reach the electrical valve 7 which is located downstream of the catalytic converter 10. During this time the pressure around the electrical valve 7 is higher than the pressure around the electrical valve 3 which is located at 15 upstream of the catalytic converter 10. The ECU calculates the time required by un-burnt hydrocarbons, Nox, and Co to reach the electrical valve 7 with the help of front and rear O2 sensor signal voltage along with calculated air mass flow across the internal combustion engine with respect to crank angle. When the unacceptable pollutants, such as carbon monoxide (CO), un-burnt hydrocarbons 20 (HC), and nitrous oxide (Nox) that get emitted from the internal combustion engine during cold and hot starting reaches the electrical valve 7, the electrical valve 7 and the electrical valve 3 open to trap all the un-acceptable emission inside the pressurized transfer chamber 1. Once the unacceptable emissions during cold and hot start of engine are captured inside the pressurized transfer chamber 1, 25 the electrical valve 7 at the tee connection and electrical valve 3 at the releasing end of the pressurized transfer chamber 1 is closed. Further, as soon all the starting emissions get captured inside the pressurized transfer chamber 1 the electrical valve 7 and the electrical valve 3 closes either together or one after the other in order to accommodate leak proof capturing of emissions. 30
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[0030] The ECU monitors the temperature of the catalytic converter 10 and the internal combustion engine. When the temperature of the catalytic converter 10 is above the light-off temperature, i.e., 350o to 450o C, the ECU opens the electrical valve 3 and the electrical valve 7 to purge captured emissions back into the catalytic converter 10 from the releasing end which equipped with electrical valve 5 3. The ECU determines the temperature of the catalytic converter through Modeled temp or through a Temperature probe. If the temperature of the catalytic converter 10 is below the light off-temperature, the ECU keeps the electrical valve 3 and the electrical valve 7 close. When the temperature of the catalytic converter 10 is above the light-off temperature, the catalytic converter 10 converts the 10 captured emissions from un-acceptable pollutant forms to acceptable pollutants by burning the un-acceptable hydrocarbons and carbon dioxide completely. The catalytic converter 10 converts the unacceptable pollutants into acceptable pollutants, such as carbon dioxide and H2O.
[0031] In another way, when the engine is running in steady condition or running 15 in transient condition, the ECU opens the electrical valve 3 and the electrical valve 7 to purge the captured emissions in the pressurized transfer chamber 1 to the catalytic converter for treatment and reduction to stable state of pollutants. Further, purging of captured emissions into the catalytic converter 10 depends on the emission reduction strategy of the vehicle. 20
[0032] By capturing of emissions after the catalytic converter 10 helps to raise the operating temperature of the catalytic converter 10 earlier. Even the starting emissions from the internal combustion engine has temperature, if these emissions are captured after passing through the catalytic converter 10, the starting emissions helps to raise the temperature of the catalytic convert 10 at an early 25 stage.
[0033] The plurality of electrical valves 3, 4, 5, 6, 7 are located at different locations in the main exhaust pipe 9 to re-circulate the emissions into the catalytic converter 10 for further purification. Further, opening and closing of the plurality of electrical valves 3, 4, 5, 6, 7 can be synchronized to avoid emission of un-30
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acceptable pollutants in the environment. As explained above, the electrical valves 3 and 7 are located in the pressurized transfer chamber 1. Where the electrical valve 4 and 5 are located in between the tee connection of the pressurized transfer chamber 1 and the tail of the main exhaust pipe 9. The opening and closing of the electrical valves 4 and 5 can be synchronized with the working of the pressurized 5 transfer chamber 1 to capture more emissions efficiently. The electrical valve 6 is provided just before the tail end of the main exhaust pipe 9. Further, the electrical valve 6 is provided after the opening of the secondary exhaust pipe 2.
[0034] The secondary exhaust pipe 2 re-circulates the emissions from the end of the main exhaust pipe to the catalytic converter 10. One end, i.e., receiving end of 10 the secondary exhaust pipe 2 is located near the end of the main exhaust pipe just before the electrical valve 6 to trap the emissions into the secondary pipe 2 and purge or redirects the trapped emissions into the catalytic converter 10 from the other end directly. The secondary exhaust pipe 2 captures the emissions which are escaped from the pressurized transfer chamber 1 and electrical valve 3, 4, 5, and 15 7. When there is sudden acceleration in the engine, the emissions if escaped from electrical valve 3, 4, 5, and 7 are trapped by the electrical valve 6 at the end of the main exhaust pipe 9. Upon determination of the sudden acceleration, the ECU closes the electrical valve 6 and redirects the emissions back into the catalytic converter for further purification. 20
[0035] During the event of sudden acceleration or fuel cut revival after deceleration of the vehicle, conventionally, extra fuel was provided in order to remove extra O2 from the catalyst of the catalytic converter 10 and the engine in order to avoid NOx production. Generally, the engine fueling becomes a little leaner during accelerations and fuel cut revival due to which NOx emissions are 25 get generated.
[0036] The exhaust system 100 reduces generation of NOx during sudden acceleration and deceleration without any extra fuel injection. The ECU understands if there is a sudden acceleration in the engine and immediately operates the plurality of electrical valves 7, 3, 4, 5. And 6. By the operations of the 30
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electrical valve 3 and 7, the pressurized transfer chamber 1 captures either CO from the emission or a mixture of CO and hydrocarbons during the event of cold / hot starting of the engine. By the operations of ECU, the pressurized transfer chamber 1 expels the captured emissions into the upstream of the catalytic converter 10 using the electrical valve 3 in order to remove the access O
2 and 5 avoid production of NOx. During sudden acceleration and deceleration revival, if the unacceptable pollutants, such as CO, THC, NOx escape further away from the pressurized transfer chamber 1, the electrical valves 4, 5, 6 are operated by the ECU in order to capture the emissions in the secondary exhaust pipe 2.
[0037] Upon closing of the electrical valve 6, the emissions are directed into the 10 secondary pipe 2 which purge the directed emissions into the catalytic converter for further purification. The pressurized transfer chamber 1 and the secondary exhaust pipe 2 works collectively with the help of electrical valves to convert the un-acceptable pollutants into acceptable pollutants effectively and efficiently.
[0038] It is easy to manufacture the present exhaust system in the vehicle. The 15 present exhaust system is cost efficient as compared to other existing solutions. Further, the present exhaust system is robust which can effectively work in any condition or at any temperature of the engine and catalytic converter to avoid emissions of harmful pollutants into environment. This exhaust system improves the fuel consumption of vehicle in sudden acceleration. 20
[0039] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures 25 depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. Plural structural components or steps can be provided by a single integrated structure or step. Alternatively, a single integrated structure or step might be divided into separate plural components or steps. In addition, while a feature of the present invention may have been 30
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described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses 5 intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature.
[0040] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present 10 subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations 15 which fall within the scope of the present subject matter.

We claim:
1. An exhaust system (100) for treating emissions of internal combustion engine and converting the emissions into acceptable form, the exhaust system (100) comprising:
a pressurized transfer chamber (1) provided after catalytic converter 5 (10) in exhaust downstream direction to capture emission passes from the catalytic converter (10); and
a plurality of electrical valves (3, 4, 5, 6, 7), control by Electronic Control Unit (ECU), provided in the exhaust pipe (9) at different locations, wherein the ECU, during the cold and hot start condition, controls opening 10 and closing of the electrical valves (3) (7) for capturing of the emissions in the pressurized transfer chamber (1) and releasing of the captured emissions in the catalytic converter (10) for further treatment of emissions.
2. The exhaust system (100) as claimed in claim 1, wherein one end of the pressurized transfer chamber (1), equipped with electrical valve (7), is 15 provided in the exhaust pipe (9) after the catalytic converter (10) to capture the emissions and other end of the pressurized transfer chamber (1), equipped with electrical valve (3), is provided above the catalytic converter (10) to release the captured emissions in the catalytic converter (10) for treatment. 20
3. The exhaust system (100) as claimed in claim 1, wherein a secondary exhaust pipe (2) provided at end of the exhaust pipe (9) to capture emissions which escapes from the pressurized transfer chamber (1), wherein the secondary pipe captures the emissions after closing of electrical valve (6) 25 controlled by the ECU.
4. The exhaust system (100) as claimed in claim 3, wherein the secondary exhaust pipe (2) opens above the catalytic converter (10) to release the captured emissions in the catalytic converter (10). 30
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5. The exhaust system (100) as claimed in claim 1, wherein the ECU, during cold start condition, determines time required by the emissions to reach location of the electrical valve (7) with help of front and rear O2 sensor signal voltage along with calculated air mass flow across engine with respect to crank angle, and the ECU sends signals to the plurality of 5 electrical valves (3, 4, 5, 6, 7) for opening and closing based on cold and hot start of engine and acceleration and deceleration of the engine.
6. The exhaust system (100) as claimed in claim 1, wherein the ECU monitors temperature of the catalytic converter (10) with the help of sensors, 10
if the temperature of the catalytic converter (10) is above light-off temperature, the electrical valve (3) opens and slowly purge the captured emissions back into the catalytic converter (10) for treatment and converting the emissions to stable state; and
if the temperature of the catalytic converter (10) is below light off 15 temperature, the electrical valve (3) remain close.
7. The exhaust system (100) as claimed in claim 1, wherein the ECU opens the electrical valve (3) to purge the captured emissions in the pressurized transfer chamber (1) slowly when the internal combustion engine is in 20 steady running condition.
8. The exhaust system (100) as claimed in claim 1, wherein the opening and closing of the plurality of electrical valves (3, 4, 5, 6, 7) is controlled by the ECU for filling, purging of emissions and recirculation of emissions in the 25 catalytic converter for complete burning hydrocarbons and CO through the pressurized transfer chamber (1) and the secondary pipe (2).
9. A method for treating emissions of internal combustion engine and converting the emissions into acceptable form in exhaust pipe system (100), the method comprising: 30
capturing the emission passes by catalytic converter (10) in a pressurized transfer chamber (1) which is provided after the catalytic
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converter (10), other end of the pressurized transfer chamber (1) is provided in upstream above the catalytic converter (10), wherein the pressurized transfer chamber (1) is equipped with one electrical valve (3,7) at both ends;
opening, by Electronic control unit (ECU), the electrical valve (7) to capture the emissions in the pressurized transfer chamber (1) during cold/hot 5 start condition;
opening, by the ECU, the electrical valve (3) slowly to purge the captured emissions in the catalytic converter (10) for complete combustion of un-burnt hydrocarbons and converting the emissions into acceptable form. 10
10. The method as claimed in claim 9, wherein the method comprises:
opening of atleast one electrical valve from a plurality of electrical valves (4, 5, 6, 7), by the ECU during sudden acceleration, to capture emissions atleast in the pressurized transfer chamber (1) and in secondary 15 pipe (2);
purging the captured emissions in the catalytic converter (10) during steady running condition to convert the emissions into acceptable form.
11. The method as claimed in claim 9, wherein the ECU opens the electrical 20 valve (3) to purge the captured emissions in the pressurized transfer chamber (1) slowly when the internal combustion engine is in steady running condition.