DESC:Technical Field
[001] The present invention pertains to the field of noxious gas treatment system that reduces exhaust gas pollutants. The invention employs an improved exhaust gas reduction system that enables effective and uniform mixing of vaporized urea with exhaust gases that have an improved reaction rate which result into harmless gas of molecular nitrogen (N2) and water vapor.
Background
[002] Automobile and like vehicle are considered as a primary source that emit exhaust gases which are rich in oxides of nitrogen. These oxides of nitrogen are root cause of greenhouse gas, air pollutant, and smog. Due to this, these oxides are considered harmful for human and environment.
[003] Various purification devices have been introduced to treat these emitted gases. Popular purification devices are based out of either a selective catalyst reduction (SCR) mechanism or non-selective catalyst reduction (SCNR) mechanism. The Selective Catalytic Reduction mechanism reduces the level of nitrogen oxide in the exhaust gas from the engine by means of catalyst elements and a reducing agent. On the other hand, non-selective catalyst reduction mechanism refers to a catalytic process where the catalyst interacts with multiple reactant molecules without discriminating between them, leading to the simultaneous reduction of various pollutants like nitrogen oxides (NOx), carbon monoxide (CO), and hydrocarbons (HC) into less harmful products like nitrogen (N2) and carbon dioxide (CO2).
[004] Conventionally, an exhaust gas treatment system employs injector unit or atomizer unit to inject urea which is reacts with oxides of nitrogen (NOx) onto a particular catalyst surface. Due to this, nitrogen gas and water is produced which are harmless. However, atomizer/ injector unit in conventional system suffer with a limitation of non-uniform mixing of urea with oxide of nitrogen. Due to this, complete reduction of exhaust gases does not occur. This has disastrous consequences, especially, in countries that have stringent laws on exhaust gas emission reduction. Additionally, this is detrimental because core issue of air-pollution remains unresolved.
[005] Secondly, non-uniform mixing of urea with oxides of nitrogen may cause formation of agglomeration of particulate matter and forming a mass of same which further requires additional cleaning process. Due to this, conventional exhaust gas treatment system is expensive in nature.
[006] Thirdly, conventional exhaust gas treatment system requires atomizer or injector arrangement is an additional concern. Further, its arrangement requires focus on inject spray angle, velocity of urea spray, volume rate of urea spray, and so on. Due to this, conventional exhaust system is incorporated with controller to manage these factors. Therefore, overall weight as well cost is high for such conventional exhaust gas treatment system.
Objective of Invention
[007] The present invention achieves, at least in part, the following objectives, which are described in various embodiments:
[008] The primary objective of the invention is to provide an improved exhaust gas reduction system that treat exhaust gases effectively and efficiently.
[009] Another objective of the invention is to provide a chamber for vaporization of urea solution.
[010] A further objective of the invention is to provide an efficient mixing of vaporized urea and exhaust gases.
[011] Yet another objective of the invention is to enable the improved exhaust gas reduction system with reduced risk of urea deposits.
[012] Still another objective of the invention is to incorporate the improved exhaust gas reduction system that is devoid of auxiliary units such as injector and atomizer units.
Summary
[013] The present invention provides an improved exhaust gas reduction system that includes a urea storage chamber, a vaporization unit, an exhaust gas unit, a mixing chamber, and a catalytic unit.
[014] Further, in present system, urea storage chamber is coupled with the vaporization unit. Further, the vaporization unit and exhaust gas unit are coupled with the mixing chamber through different path respectively. The amalgamation compound from mixing chamber is provided to the catalytic unit.
[015] The urea solution from the urea storage chamber is provided into vaporization unit. In this unit, urea solution is changed to vaporized phase which helps in its heating and decomposition. The vaporized urea reacts with exhaust gases into mixing chamber. In catalytic unit, generated compound from mixing chamber undergoes selective catalyst reaction process to provide harmless molecular nitrogen and water vapor.
[016] The present system enables an effective and improved reaction between vaporized urea and exhaust gases to provide harmless gas. Advantageously, present system is devoid of urea deposit because of which auxiliary cleaning process is not required. Additionally, the lack of urea deposit disables agglomeration of particulate matter thereby reaction between vaporized urea and exhaust gas does not hinder.
Brief Description of the Accompanying Drawings
[017] The foregoing summary and the following detailed description of various embodiments are to be understood in conjunction with the accompanying drawings. These drawings are provided solely for illustrative purposes and depict exemplary embodiments of the invention. It should be noted that the disclosed subject matter is not limited to the specific methods, structures, or instrumentalities shown and described herein.
[018] Figure 1 illustrates an improved exhaust gas reduction system accordance with an embodiment of present invention.
[019] Figure 2 illustrates a method of reducing exhaust gases through an improved exhaust reduction system in accordance with an embodiment of present invention.
List of Reference Numerals Used in the Description and Drawings
100 Exhaust Gas Reduction System 101 Urea Storage Chamber
103 Vaporization Unit 105 Mixing Chamber
107 Exhaust Gas Unit 109 Catalytic Unit

Detailed Description
[019] Embodiments of the present disclosure are elucidated herein with reference to the accompanying drawings.
[020] Embodiments are presented to comprehensively convey the scope of the present disclosure to those skilled in the relevant art. Detailed descriptions encompass various components and methods, facilitating a thorough understanding of the embodiments. It should be understood that the details provided in the embodiments are not intended to limit the scope of the present disclosure. In certain embodiments, commonly known apparatus structures and techniques are not exhaustively described.
[021] The terminology employed in the present disclosure serves the purpose of elucidating specific embodiments and should not be construed to restrict the scope of the present disclosure. The terms "a", "an", and "the" may encompass plural forms unless context suggests otherwise. Expressions such as "comprises", "comprising", "including", and "having" denote open-ended transitional phrases, indicating the presence of specified features without excluding the addition of other features.
[022] When an element is referenced as being "embodied thereon", "engaged to", "coupled to", or "communicatively coupled to" another element, it signifies direct placement, engagement, connection, or coupling. As used herein, "and/or" encompasses all possible combinations of one or more associated listed elements.
[023] In consideration of increasing greenhouse gas emission and air pollution, strict laws have been introduced in developed and developing countries, wherein automobile or like vehicle must incorporate system that treat exhaust gases. In a conventional exhaust gas emission treatment system, an auxiliary unit of atomizer/injector is deployed. The injector unit is configured to inject urea which reacts with exhaust gas having oxides of nitrogen (NOx). This mixture reacts in accordance with a selective catalyst reduction (SCR) mechanism. Due to this, resultant combination of harmless molecular nitrogen gas and water vapor is produced.
[024] However, conventional exhaust gas emission system suffers from following disadvantage:
- Injector/atomizer are auxiliary units that require to be arrange at a particular angle and increases overall weight of the conventional system;
- Non-uniform mixing of urea with exhaust gases leading to insufficient reduction of exhaust gases;
- Injector/atomizer unit causes formation of urea deposit over catalyst surface that impair and hinder reaction of urea with that of exhaust gases; and
- Urea deposit leading to particulate matter agglomeration which requires additional cleaning process and hence conventional system is quite expensive.
[025] The present invention relates to an exhaust gas treatment system (100) configured for reducing air pollutants such as nitrogen oxides (NOx) from exhaust gases produced by internal combustion engines or combustion-based systems used in vehicles, power plants, or other industrial equipment. The system comprises a urea storage chamber (101) that is configured to store an aqueous urea solution. The chamber (101) is constructed from materials resistant to chemical degradation by urea and is shaped to ensure easy integration into mobile or stationary exhaust systems. A delivery mechanism, such as a controlled conduit or pump, facilitates the controlled flow of urea solution from the chamber to a vaporization unit (103).
[026] The vaporization unit (103) is coupled to the urea storage chamber (101) and receives the urea solution. It is configured to heat the urea solution using thermal energy, preferably harnessed from exhaust steam or another high-temperature medium from the engine. The heating of the urea solution results in its vaporization and decomposition into gaseous components such as ammonia (NH3) and isocyanic acid (HNCO). These gases are referred to collectively as vaporized urea. The system may include thermal sensors or control logic to ensure that the vaporization occurs efficiently and safely, without forming unwanted byproducts or deposits within the unit. Importantly, the amount of urea solution provided to the vaporization unit (103) is regulated based on the operating conditions of the engine or system. For example, in a cold-start scenario or during variable engine loads, a control module adjusts the quantity of urea to ensure that the vaporized output matches the amount of exhaust gases being treated.
[027] The vaporized urea is directed into a mixing chamber ( 105), which is coupled to both the vaporization unit (103) and an exhaust gas unit ( 107). The exhaust gas unit ( 107) supplies hot exhaust gases from the combustion system, including pollutants such as NOx, CO, CO2, unburnt hydrocarbons, and particulate matter. [028] The mixing chamber ( 105) is designed to uniformly combine the vaporized urea with these exhaust gases. The phase uniformity between the vaporized urea and the exhaust gases enhances the reaction rate and mixing efficiency, promoting optimal conversion of NOx during the next stage. The mixing process may also lead to the formation of precipitates such as cyanuric acid or urea-based residues under certain thermochemical conditions. These precipitates are separated from the gas stream and collected in a separate collection chamber (not shown in the claims but provided for system integrity and maintenance). This chamber is positioned adjacent or below the mixing chamber ( 105) to utilize gravity-assisted deposition and may be removable or self-cleaning.
[029] The uniformly mixed gas stream is then passed into a catalytic unit (109), which is coupled to the mixing chamber ( 105). The catalytic unit (109) includes a surface embedded or coated with catalyst materials selected from a group consisting of vanadium (V), titanium (Ti), tungsten (W), or combinations thereof. These catalysts facilitate a selective catalytic reduction (SCR) mechanism, wherein the ammonia present in vaporized urea reacts selectively with NOx species to produce harmless nitrogen gas (N2) and water vapor (H2O), without forming secondary pollutants such as ammonia slip or nitrous oxide. The catalyst surface is structured to offer high surface area, temperature resistance, and optimized gas residence time to enhance the overall efficiency of pollutant conversion.
[030] The system operates in coordination with real-time sensors and a control module, which monitor engine load, exhaust temperature, NOx concentration, and urea levels. Based on these readings, the amount of urea supplied to the vaporization unit (103) is modulated to match the quantity of NOx present in the exhaust stream, thereby ensuring stoichiometric balance and improving efficiency. In some embodiments, the system can be integrated with existing onboard diagnostics to enable compliance with emissions regulations and allow fault detection or maintenance alerts.
[031] Overall, the system (100) as described provides a compact, efficient, and adaptable solution for reducing NOx and other gaseous pollutants using vaporized urea and SCR, suitable for use across a wide range of combustion-driven equipment. The inclusion of phase-unified mixing, adaptive dosing, and precipitate collection further improves its reliability and environmental performance.
[032] In accordance with the present invention, a method for treating exhaust gases using an improved exhaust gas treatment system is provided. The method begins with storing a urea solution in a urea storage chamber (101), which is constructed from chemically inert materials capable of withstanding temperature fluctuations and urea-induced corrosion. This chamber acts as the primary reservoir for the urea solution used throughout the treatment process. A conduit or pumping mechanism ensures fluidic communication between the urea storage chamber and the vaporization unit (103), allowing for a controlled supply of urea solution based on the operational requirements of the system.
[033] Once transferred to the vaporization unit (103), the urea solution is subjected to thermal energy, preferably provided by the engine’s exhaust heat or an auxiliary heater, resulting in the formation of vaporized urea. The vaporization process may cause partial decomposition of the urea into ammonia (NH3) and isocyanic acid (HNCO), thus enhancing the chemical reactivity needed for downstream processing. The amount of urea delivered to the vaporization unit is adaptively controlled depending on engine operating conditions such as cold start, load demands, or emission levels, thereby optimizing treatment efficiency and conserving reagent usage.
[034] Simultaneously, exhaust gases produced by the engine are routed through an exhaust gas unit ( 107), which channels the gas stream toward the mixing chamber (107). These gases typically contain nitrogen oxides (NO?), carbon monoxide (CO), hydrocarbons, and other pollutants. The vaporized urea from the vaporization unit (103) and the exhaust gases from the exhaust gas unit ( 107) are introduced into the mixing chamber ( 105) through distinct inlets. The mixing chamber is geometrically and thermodynamically configured to promote phase matching between the vaporized urea and the hot exhaust gases, which enhances the rate and uniformity of reaction. Turbulent flow dynamics within the chamber support complete and homogeneous interaction of these reactants.
[035] During this process, any non-gaseous byproducts or precipitates formed in the mixing chamber, such as cyanuric acid, are diverted into a separate collection chamber designed to isolate solid waste without obstructing gas flow. The combined stream of uniformly mixed vaporized urea and exhaust gases is subsequently directed to a catalytic unit (109). The catalytic unit contains one or more catalyst substrates made of materials such as vanadium, titanium, tungsten, or their composites. Upon contacting the catalyst surface, the NO? in the exhaust gases undergoes selective catalytic reduction (SCR) reactions with the ammonia derived from the vaporized urea. These reactions primarily convert harmful NO? into benign nitrogen gas (N2) and water vapor (H2O).
[036] The catalyst is designed to facilitate reaction selectivity while minimizing ammonia slip, thus ensuring environmental compliance. Additionally, a control module integrated within the system may use engine performance data and sensor inputs to continuously adjust the urea injection rate and vaporization profile in real time. This method, therefore, allows dynamic exhaust gas treatment suitable for diverse applications such as automotive systems, thermal power plants, and other pollutant-generating apparatuses.
[037] In some embodiments, the quantity of urea solution provided to the vaporization unit (103) is dynamically adjusted based on operating conditions of the engine, such as cold starts, idle periods, or full load. Sensors detecting temperature, pressure, or engine RPM may relay data to a control module, which in turn regulates the urea dosing rate accordingly. The control system is configured to optimize the amount of vaporized urea generated in response to varying exhaust gas conditions, thereby improving the efficiency of the exhaust gas reduction process.
[038] The described system (100) is not limited to automotive applications but may be employed in a variety of transport mediums and industrial applications. Such applications may include, but are not limited to, diesel generator exhausts, maritime vessels, locomotives, and thermal power plants, where reduction of NOx and other pollutants is required.
[039] In one embodiment, the system (100) may include a redundant dosing line or dual vaporization units to ensure uninterrupted operation in the event of partial failure or clogging. Additionally, the system may incorporate error-checking routines that detect under-dosing or inefficient mixing, providing notifications or adjusting parameters to maintain optimal performance.
[040] The catalyst surface of the catalytic unit (109) may comprise at least one of vanadium, titanium, tungsten, or other suitable catalytic materials, such as cordierite, silicon carbide, or metal monoliths, as a support for the active catalyst compounds. The shape, porosity, and thermal stability of the catalyst support material may vary depending on the specific application of the system and the concentration of NOx in the exhaust gases.
[041] The exhaust gas treatment system (100) may further be integrated with an onboard diagnostic system configured to monitor and report the performance of the system. The diagnostic system may monitor various parameters, including but not limited to, catalyst efficiency, urea consumption, and the level of emissions produced, supporting compliance with regulatory emission standards.
[042] The system (100) may include provisions for routine maintenance, such as cleaning ports or access valves located within the mixing chamber ( 105) or collection chamber, to remove solid deposits that may accumulate over time. These provisions ensure that the system maintains its efficiency and performance over extended operational periods.
[043] The exhaust gas treatment system (100) and method described herein offer a highly efficient and adaptable solution for the reduction of harmful pollutants, particularly NOx, from exhaust gases. By leveraging a dynamic urea dosing mechanism, the system responds to varying engine conditions, optimizing the amount of vaporized urea to match exhaust gas output. The integration of a mixing chamber and catalytic unit ensures uniform reaction and effective selective catalytic reduction, converting harmful nitrogen oxides into harmless nitrogen gas and water vapor. This invention provides a robust solution applicable not only in automotive systems but also in a wide range of industrial and transport applications, with flexibility for maintenance, error-checking, and compliance monitoring. Furthermore, the incorporation of various catalytic materials and operational configurations enhances the system's adaptability, making it a versatile and long-lasting solution for exhaust gas treatment.
[044] Technical Advantages: The present invention provides several significant technical advantages. First, the system (100) offers enhanced efficiency in the reduction of nitrogen oxides (NOx) in exhaust gases through a combination of precise urea dosing and selective catalytic reduction. By dynamically adjusting the amount of vaporized urea based on engine operating conditions, the system ensures optimal NOx reduction under varying loads and temperature conditions, including cold starts. This results in improved overall system performance and reduced environmental impact.
[045] Additionally, the use of a mixing chamber ( 105) to uniformly mix vaporized urea with exhaust gases ensures a more efficient reaction at the catalyst surface, reducing the likelihood of incomplete NOx conversion. The catalyst unit (109) is designed to operate effectively with various catalyst materials, such as vanadium, titanium, and tungsten, providing flexibility in selecting the most suitable catalyst for specific operational requirements. Furthermore, the system's ability to integrate with existing onboard diagnostic systems allows for real-time monitoring of system performance, enabling prompt identification of any issues, such as under-dosing or catalyst inefficiency, thereby maintaining optimal performance over the long term.
[046] Economical Advantages: The invention also provides substantial economical advantages. The system's dynamic control over urea dosing ensures that the urea solution is efficiently utilized, minimizing waste and reducing the overall cost of urea consumption. By adjusting the dosing rate based on real-time engine conditions, the system prevents overuse of urea, which can lead to unnecessary operational costs. Furthermore, the efficient reduction of NOx and other pollutants results in reduced wear and tear on the exhaust treatment components, leading to lower maintenance costs and extended service life of the system.
[047] From an environmental perspective, the system helps vehicles and industrial systems comply with stringent emission standards, avoiding potential penalties or fines associated with non-compliance. The system's ability to maintain consistent and efficient NOx reduction across varying engine conditions also contributes to improved fuel efficiency, offering long-term savings in fuel costs.
[048] Overall, the invention provides a cost-effective and environmentally friendly solution for exhaust gas treatment, making it economically advantageous for both manufacturers and end-users seeking to reduce operational expenses while adhering to environmental regulations.
[049] The embodiments described herein, along with their various features and advantageous details, are explained with reference to specific non-limiting embodiments provided in the following description. The examples presented are intended solely to facilitate an understanding of the invention's implementation and to enable those skilled in the art to practice the embodiments described herein. Those skilled in the art, by applying their current knowledge, may modify or adapt these embodiments for various applications without departing from the fundamental concept of the invention. Such modifications and adaptations are intended to be within the scope and meaning of the disclosed embodiments. ,CLAIMS:CLAIMS
I/We Claim
1. An exhaust gas treatment system (100) comprising:
• a urea storage chamber (101) configured to store a urea solution;
• a vaporization unit (103) operatively coupled to the urea storage chamber (101), the vaporization unit (103) configured to receive and heat the urea solution to produce vaporized urea;
• a mixing chamber (105) operatively coupled to the vaporization unit (103) and an exhaust gas unit ( 107), the mixing chamber ( 105) configured to receive the vaporized urea and exhaust gases and to facilitate uniform mixing thereof; and
• a catalytic unit (109) operatively coupled to the mixing chamber ( 105), the catalytic unit (109) comprising a catalyst surface configured to enable selective catalytic reduction of nitrogen oxides (NO?) into nitrogen gas and water vapor.

2. The system (100) as claimed in claim 1, wherein the vaporization unit (103) is configured to heat the urea solution using hot exhaust steam from the exhaust gas unit ( 107).

3. The system (100) as claimed in claim 1, wherein heating the urea solution in the vaporization unit (103) causes decomposition into ammonia (NH3) and isocyanic acid (HNCO).

4. The system (100) as claimed in claim 1, wherein the vaporized urea and exhaust gases are mixed in the mixing chamber ( 105) in a common gas phase to enhance reaction efficiency.

5. The system (100) as claimed in claim 1, wherein the catalytic unit (109) comprises at least one catalyst selected from the group consisting of vanadium, titanium, and tungsten-based catalysts.

6. The system (100) as claimed claim 1, wherein the exhaust gas unit ( 107) is configured to supply exhaust gases containing oxides of nitrogen (NO?), carbon monoxide (CO), hydrocarbons (HC), and particulate matter (PM).

7. The system (100) as claimed in claim 1, wherein the selective catalytic reduction in the catalytic unit (109) reduces at least NO? and optionally reduces other exhaust pollutants.

8. The system (100) as claimed in any of the preceding claims, wherein the system (100) is integrated into a vehicle, a thermal power plant, or an industrial emission control apparatus.

9. The system (100) as claimed in claim 1, wherein the vaporization unit (103) is thermally insulated to improve heating efficiency.

10. The system (100) as claimed in any of the preceding claims, wherein a control unit regulates the flow of urea solution to the vaporization unit (103) based on exhaust gas temperature or flow rate.

11. The system (100) as claimed in any of the preceding claims, wherein the amount of urea solution supplied to the vaporization unit (103) is dynamically controlled based on engine operating conditions.

12. The system (100) as claimed in claim 11, wherein the engine operating conditions include at least one of: engine temperature, engine load, cold start conditions, and exhaust flow rate.

13. The system (100) as claimed in any of the preceding claims, wherein the vaporization unit (103) is configured to produce an amount of vaporized urea substantially proportional to the quantity of exhaust gases received from the exhaust gas unit ( 107).

14. The system (100) as claimed in any of the preceding claims, wherein a control module is configured to adjust the injection rate of the urea solution based on real-time sensor data from the exhaust gas unit ( 107).

15. The system (100) as claimed in any of the preceding claims, wherein the mixing chamber ( 105) is operatively connected to a separate collection chamber configured to collect precipitates or by-products formed during the mixing of vaporized urea and exhaust gases.

16. The system (100) as claimed in claim 15, wherein the collection chamber is configured to isolate and store solid or liquid residues without interfering with the flow of vaporized urea and exhaust gases toward the catalytic unit (109).

17. The system (100) as claimed in any of the preceding claims, wherein the collection chamber is detachable or includes a cleaning mechanism for periodic removal of accumulated substances.

18. A method for treating exhaust gases, comprising:
• storing a urea solution in a storage chamber (101);
• supplying the urea solution to a vaporization unit (103);
• heating the urea solution in the vaporization unit (103) to generate vaporized urea;
• directing the vaporized urea and exhaust gases into a mixing chamber ( 105) for uniform mixing; and
• conveying the mixed gases to a catalytic unit (109) to perform selective catalytic reduction of NO? into nitrogen gas and water vapor.
19. The method as claimed in claim 18, wherein the vaporized urea is generated by heating the urea solution using hot exhaust steam.

20. The method as claimed in claim 18, wherein the urea solution decomposes into ammonia (NH3) and isocyanic acid (HNCO) during vaporization.

21. The method as claimed in claim 18, wherein the mixing of vaporized urea and exhaust gases occurs in the same phase to enhance reaction uniformity.

22. The method as claimed in claim 18, wherein the exhaust gases comprise oxides of nitrogen (NO?).

23. The method as claimed in claim 18, wherein the catalytic unit (109) comprises a catalyst selected from vanadium, titanium, tungsten, or a combination thereof.

24. The method as claimed in claim 18, wherein the system is implemented in an internal combustion engine of a vehicle, a thermal power plant, or an air-polluting apparatus.

25. The method as claimed in claim 18, wherein the vaporization unit (103) and mixing chamber ( 105) are integrated into a compact exhaust treatment module.

26. The method as claimed in claim 18, wherein the vaporized urea and exhaust gases are uniformly mixed before being introduced to the catalytic unit (109).

27. The method as claimed in claim 18, further comprising regulating the vaporization temperature based on engine parameters.

28. The method as claimed in claim 18, wherein the amount of urea solution supplied to the vaporization unit (103) is varied based on engine operating conditions.

29. The method as claimed in claim 28, wherein the engine operating conditions include at least one of: engine temperature, engine load, or cold start conditions.

30. The method as claimed in claim 18, wherein the quantity of vaporized urea generated is substantially proportional to the flow rate of exhaust gases.

31. The method as claimed in claim 18, further comprising detecting engine operating parameters and dynamically adjusting urea injection in real time.

32. The method as claimed in claim18, further comprising collecting by-products or precipitates formed in the mixing chamber ( 105) in a separate collection chamber.

33. The method as claimed in claim 32, wherein the collection chamber is configured to isolate and retain solid or liquid residues without impeding gas flow.

34. The method as claimed in claim 32, wherein the collection chamber includes a cleaning mechanism or is detachable for maintenance.