This application claims the benefit of priority to Iran Application Serial Number 139550140003014638, filed on Feb. 17, 2017, the entire content of which is incorporated herein by reference.
This subject matter relates generally to converting exhaust fume heat to electricity in an internal combustion engine, and more particularly to generating hydrogen from the energy of engine emissions in existing internal combustion engines while minimizing engine retrofitting and reducing engine emissions.
Great efforts have been spent in recent years in developing system that reduce the amount of fossil fuel consumption and harmful emission of internal combustion (IC) engines. Hybrid vehicles are one of such systems. In hybrid vehicles, a high-power electric motor is used along with an IC engine for power. The IC engine helps charge the electric motor which is in turn used to drive the vehicle for some distance before the electric motor loses its charge. Although, this mechanism reduces emission and fossil fuel consumption, due to the complexity of the transmission lines in these vehicles, which are linked to two sources of power, it is very difficult to retrofit a regular fossil fuel vehicle with a hybrid system. Additionally, hybrid vehicles are sometimes difficult to charge, particularly in public places, because charging stations for these vehicles are not yet commonly established. Another disadvantage of hybrid vehicles is the rapid discharge of the systems' batteries.
Another type of system used to reduce harmful emissions in IC engines utilizes a electrocatalytic converter. In a typical gasoline-run vehicle, the use of an electrocatalytic converter helps reduce emissions and fuel consumption and avoids some of the disadvantages of hybrid systems. Although such electrocatalytic converter systems have many advantages, their operations can be substantially improved.
Therefore, a need exists for providing an improved electrocatalytic converter system for use with IC engines that efficiently reduces harmful emissions and reduces fuel consumption.
A system for reducing fossil fuel consumption and emissions in an engine is provided. In one implementation, the system includes a waste heat recovery unit including a condenser connected to a first pump for injecting a working fluid into a heat exchanger configured to convert the working fluid into steam injected into an expander; a generator connected to the expander for generating electricity; a battery for storing the generated electricity; and a water electrolysis unit including a water container for storing water, and a second pump for pumping the water into an electrocatalytic converter. The electrocatalytic converter includes a plurality of electrode plates for conducting the generated electricity through the water to electrolyze the water and generate a hydrogen gas for injection into the engine. The hydrogen gas reduces an amount of fossil fuel needed for running the engine and reduce engine emissions, and the heat exchanger uses heat from exhaust fumes emitted from the engine to convert the working fluid to steam.
Features of the subject technology are set forth in the appended claims. However, for purpose of explanation, several implementations of the subject technology are set forth in the following figures.
In the following detailed description, numerous specific details are set forth by way of examples in order to provide a thorough understanding of the relevant teachings. However, it should be apparent to those skilled in the art that the present teachings may be practiced without such details. In other instances, well known methods, procedures, components, and/or circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present teachings. As part of the description, some of this disclosure's drawings represent structures and devices in block diagram form in order to avoid obscuring the invention. In the interest of clarity, not all features of an actual implementation are described in this specification. Moreover, the language used in this disclosure has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter, resort to the claims being necessary to determine such inventive subject matter. Reference in this disclosure to “one embodiment” or to “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention, and multiple references to “one embodiment” or “an embodiment” should not be understood as necessarily all referring to the same embodiment.
Recent demands for reduction in fuel consumption and harmful emissions of IC engines have led to the use of electrocatalytic systems in vehicles. An electrocatalytic converter may be installed in gasoline-run vehicles to convert water to hydrogen and oxygen which is then injected into the intake air of the IC to reduce fuel consumption and emissions. However, such systems generally require electrical energy to be supplied to the electrode plates of the electrocatalytic systems. This electric energy is often supplied by the vehicle's main battery which results in rapid discharge of the battery. Furthermore, the battery is generally charged by the alternator which is connected to the motor (engine crank shaft). This means that the energy of the electrode plates of the electrocatalytic converter is supplied from the energy (mechanical power) of the vehicle engine. This in itself creates a source of energy inefficiency.
A solution is proposed here to solve these issues and more by providing an improved electrocatalytic system for use in motor vehicles. In one embodiment, the improved electrocatalytic system involves converting the heat generated by exhaust fumes to electrical energy which then powers an electrocatalytic converter. By reusing the engine's energy loss through the exhaust system, the improved system reduces fuel consumption, increases engine efficiency and reduces engine emissions.
Once the working fluid is vaporized, it enters the expander 130 where the pressure created by the steam moves the expander blades (not shown) thus causing the expander to start rotating. The rotation causes an output shaft (not shown) of the expander 130 to turn. The output shaft of the expander 130 is connected to an electric generator 135. The rotation of the expander shaft causes the electric power generator 135 to produce electricity with a voltage range and alternating current.
After moving through the expander 130, the steam is routed to a condenser 140 for converting the steam back to liquid. In one implementation, the condenser 140 includes a fan (not shown) for cooling. Using the fan, the steam is converted from vapor to liquid form before moving back into the pump 120 to be pumped into the heat exchanger 125 for another cycle. This cycle may be referred to as an Organic Rankine cycle, which is known in the art as a cycle where an operating organic fluid is continuously evaporated and condensed.
In addition to the energy generating section 105 for producing electric energy, the system 100 includes an electric transmission and control section 110. The electric transmission and control section 110 includes, in one implementation, a rectifier 145 which may be a diode bridge rectifier used for converting alternating-current (AC) to direct-current (DC). Once converted, the DC current enters a relay switch 150 which is connected to a fuel switch key 155. The fuel switch key 55 may be located inside the vehicle for easy accessibility for a user of the vehicle. For example, the fuel switch key 155 may be placed around the steering vehicle for enabling the driver to select the type of fuel they desire to use for the vehicle at a given time. The switch may present two options to the driver for selecting either a single only fuel mode or a hybrid fuel mode. When the gasoline only fuel option is selected, power is not sent from the fuel switch key 155 to the relay 150. As a result, the relay contact does not change, which causes the electrical energy generated by the energy generating section 105 to flow into the battery 160. In this manner, the electric energy is stored in the battery 160 for future use. When the fuel switch key 155 is on the hybrid fuel mode, electric energy is sent to the relay 150, thereby changing the contact of the relay such that the energy produced by the energy generating section 105 is transferred to the electrocatalytic converter plates 165.
The battery 160 is, in one implementation, a hybrid battery system having 12 or 24 volts, or a different voltage. The battery 160 is charged when the vehicle is in single-fuel mode. The energy stored on the battery 160 can be used to supply energy to the first pump 120 of the energy generating section 105, the water transfer pump 175 of the water electrolysis section 115 and/or the cooling fan of the condenser 140. The battery 160 can also be used when there is a problem with the main battery of the vehicle. In this manner, the system 100 not only does not require additional energy for operation, but also can be used to supplement the vehicle's battery, when needed.
The water electrolysis section 115 of system 100 includes a water tank 170, a water transfer pump 175 and the electrocatalytic converter 165. The water tank 170 contains water used in the electrolysis mechanism. The water transfer pump 175 is connected to and transfers water from the water tank 170 to the electrocatalytic converter 165. The electrocatalytic converter 165 contains electrode plates (see
By supplying electrical current to the electrode plates, the water inside the electrocatalytic converter 165 is electrolyzed to produce oxygen and hydrogen gases. The produced oxygen and hydrogen gases are then transported to the combustion chamber (not shown) of the IC engine 185. Thus, the engine is fed with oxygen and hydrogen gases in addition to the traditional source of fuel it uses for operation. These oxygen and hydrogen gases increase the thermal value of the traditional fuel and as a result increase its combustion, thereby decreasing the amount of fossil fuel needed for the engine's operation. To reduce the amount of fossil fuels used by the system 100, when the electrocatalytic converter 165 begins injecting oxygen and hydrogen into the combustion chamber of the IC engine 185, an oxygen sensor (not shown) sends an enriched-fuel message to an engine control unit (ECU) (not shown) to inform the ECU of the existence of oxygen and hydrogen fuel. As a result, the ECU reduces the fuel injection rate of the injectors that provide the fossil fuel to the engine 185. ECUs are well known in the art and as such their structure and function is not described in detail here. However, even though, the amount of traditional fuel used by the engine is reduced, the mechanical energy of the engine will remain the same as before, as hydrogen is substituting some of the required fossil fuel.
After burning the fuel, emitted gases from the engine 185 are routed to the turbine 195 to be transferred to the heat exchanger 125, where their heat is utilized for vaporizing the working fluid, before they are routed through the exhaust pipe outlet (see
It has been established that vehicles often produce the most amount of pollutants when they are running on low speeds. For example, when a bus stops at the bus station or vehicles are stuck in traffic or waiting behind a red light, they generate the most of amount of pollutants. The inventors have determined that if system 100 is activated when the vehicle is running at a slow speed, in one implementation, the organic Rankine cycle can supply the electrocatalytic convertor power requirement completely because the low boiling temperature of the organic working fluid. This means that, in one implementation, the system 100 achieves its best results when the system is activated while the vehicle is running at a slow speed (and low exhaust gas temperature) and producing increased pollutant emissions. The performance of this system 100 is almost the same as hybrid vehicles.
The length of the heat exchange tube 200 can vary depending on the size and dimensions of the vehicle and/or other variables. For example, the length of the heat exchange tube 200 could extend up to 2 meters. In one implementation, multiple heat exchange tubes 200 are used to form a triangular arrangement with a 30 degrees angle between each two heat exchanger tubes, for maximum efficiency. According to some analyses conducted by the inventors, the heat exchanger 125 is capable of transferring about 70% of the exhaust gas heat to the working fluid with a back pressure of less than 30 kPa. Thus, the working fluid enters the skin of the heat exchange tube 200 in a liquid state and exits a superheated steam state.
In one implementation, the electrocatalytic converter 165 is different from currently used electrocatalytic converters in at least a few ways. For example, as discussed above, the electrode plates used in the electrocatalytic converter 165 have increased contact areas. Furthermore, to increase the conductivity of the electrocatalytic converter 165, two types of steel may be used for the cathode and anode plates. For example, stainless steel 302 and 304 may be used for the cathode plate and steel 316L may be used for the anode plates. Moreover, in one implementation, an inverse electron pump is created by placing two absorbing poles in the outlet path. The absorbing poles introduce a stimulating force to the ion gases produced by the electrocatalytic converter, which generally increases the engine's volumetric efficiency. In another implementation, an active carbon filter fuel dryer is also utilized in the electrocatalytic converter for dehydrating the generated hydrogen and oxygen gases.
Accordingly, the improved electrocatalytic system provides an efficient, less costly and retrofittable system for reducing harmful emissions and fossil fuel consumption in vehicles by utilizing a Rankine cycle system that takes advantage of exhaust fume heat to generate electricity. The generated electricity is used in electrolyzing water which produces hydrogen used as a supplemental fuel in the engine.
The separation of various components in the examples described above should not be understood as requiring such separation in all examples, and it should be understood that the described components and systems can generally be integrated together in a single packaged into multiple systems.
While the foregoing has described what are considered to be the best mode and/or other examples, it is understood that various modifications may be made therein and that the subject matter disclosed herein may be implemented in various forms and examples, and that the teachings may be applied in numerous applications, only some of which have been described herein. It is intended by the following claims to claim any and all applications, modifications and variations that fall within the true scope of the present teachings.
Unless otherwise stated, all measurements, values, ratings, positions, magnitudes, sizes, and other specifications that are set forth in this specification, including in the claims that follow, are approximate, not exact. They are intended to have a reasonable range that is consistent with the functions to which they relate and with what is customary in the art to which they pertain.
The scope of protection is limited solely by the claims that now follow. That scope is intended and should be interpreted to be as broad as is consistent with the ordinary meaning of the language that is used in the claims when interpreted in light of this specification and the prosecution history that follows and to encompass all structural and functional equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirement of Sections 101, 102, or 103 of the Patent Act, nor should they be interpreted in such a way. Any unintended embracement of such subject matter is hereby disclaimed.
Except as stated immediately above, nothing that has been stated or illustrated is intended or should be interpreted to cause a dedication of any component, step, feature, object, benefit, advantage, or equivalent to the public, regardless of whether it is or is not recited in the claims.
It will be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein. Relational terms such as first and second and the like may be used solely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “a” or “an” does not, without further constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.
The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various implementations for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed implementations require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed implementation. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter.
Number | Date | Country | Kind |
---|---|---|---|
13955014000301463 | Feb 2017 | IR | national |