SYSTEM AND METHOD FOR WASTE HEAT RECOVERY

Abstract

ABSTRACT Disclosed is a system and a method for recovering energy from waste heat. The system comprises a recuperator, a heat exchanger, an evaporator, an expansion unit, a condenser, and a pump. The recuperator is fluidly connected to the exhaust manifold of a dual fuel engine and is adapted to preheat a working fluid using heat of exhaust gases from the dual fuel engine. The heat exchanger is adapted to transfer additional heat from the exhaust gases to the preheated working fluid. The evaporator is adapted to vaporize the preheated working fluid using the heat received from the heat exchanger. The expansion unit is adapted to cause an expansion of the vaporized working fluid and convert thermal energy into mechanical energy. The condenser is adapted to condense the expanded working fluid into a liquid state. The pump is adapted to circulate the liquid working fluid to the recuperator and the heat exchanger in a closed-loop cycle. FIG. 1

Specification

Description:SYSTEM AND METHOD FOR WASTE HEAT RECOVERY
TECHNICAL FIELD
[0001] The present disclosure relates to the field of energy recovery systems, specifically for converting waste heat into useful energy. In particular, the present disclosure relates to a waste heat recovery system that captures and converts heat energy from exhaust gases of dual fuel engines and improves overall energy efficiency in industries such as automotive, marine, and power generation.
BACKGROUND
[0002] The subject matter discussed in the background section should not be assumed to be prior art merely because of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in prior arts. The subject matter in the background section merely represents different approaches, which in and of themselves may correspond to implementations of the claimed technology.
[0003] Energy efficiency has become a point of focus for various industries, particularly those relying on Internal Combustion (IC) engines for power generation, transportation, and other applications. Conventional IC engines, including dual fuel engines, generate substantial amounts of waste heat during operation, a significant portion of which is expelled through exhaust gases. The waste heat represents a lost opportunity for energy recovery and fuel efficiency improvement.
[0004] Dual fuel engines, which typically operate using a combination of fuels such as natural gas and diesel, are designed to reduce emissions and optimize fuel consumption. However, the dual fuel engines, similar to the conventional IC engines, are inefficient in terms of fully utilizing the energy potential of the fuel. During combustion, only a fraction of the fuel's energy is converted into mechanical work, while the remainder is lost as waste heat, primarily through exhaust gases and cooling systems.
[0005] Heretofore, various methods have been developed to capture and reuse the waste heat in order to improve overall engine efficiency. For instance, steam-based Rankine cycles and heat exchangers have been used to recover high-temperature waste heat in power plants and other industrial applications. However, the same have not been successful in recovering the waste heat owing to large size, complexity and non-suitability to lower-temperature waste heat, particularly in mobile applications such as automotive and marine industries.
[0006] Moreover, existing waste heat recovery systems struggle to perform efficiently when applied to engines with fluctuating exhaust gas temperatures and compositions, as in the dual fuel engines. The combination of diesel and natural gas combustion produces exhaust gases that vary in temperature, flow rate, and chemical composition, depending on the engine's operating conditions and fuel mixture. This variability poses challenges to the design of heat recovery systems, which are typically optimized for more stable conditions.
[0007] One of the main limitations of the existing waste heat recovery systems is the inability to adapt dynamically to the variable conditions since the existing waste heat recovery systems rely on fixed configurations, which suffer from reduced efficiency or operational issues when conditions change. For example, in the dual fuel engines, the presence of varying fuel mixes can cause temperature fluctuations that the existing waste heat recovery systems are not equipped to handle effectively.
[0008] Therefore, to meet the above-mentioned challenges associated with the existing waste heat recovery systems, there lies a need for an adaptable and efficient system that can maximize energy recovery under varying exhaust gas conditions, leading to reduced fuel consumption and emissions while increasing power output.
SUMMARY
[0009] This summary is provided to introduce a selection of concepts in a simplified format that is further described in the detailed description of the invention. This summary is not intended to identify key or essential inventive concepts of the invention, nor is it intended for determining the scope of the invention.
[0010] According to an aspect of the present disclosure, a system for recovering energy from waste heat is disclosed. The system comprises a recuperator, a heat exchanger, an evaporator, an expansion unit, a condenser and a pump. The recuperator is fluidly connected to an exhaust manifold of a dual fuel engine. The recuperator is adapted to preheat a working fluid using heat of exhaust gases from the dual fuel engine. The heat exchanger is fluidly connected to the recuperator and is adapted to transfer additional heat from the exhaust gases to the preheated working fluid. The evaporator is fluidly connected to the heat exchanger and is adapted to vaporize the preheated working fluid using the heat received from the heat exchanger. The expansion unit is fluidly connected to the evaporator and is adapted to cause an expansion of the vaporized working fluid and convert thermal energy into mechanical energy. The condenser is fluidly connected to the expansion unit and is adapted to condense the expanded working fluid into a liquid state. The pump is fluidly connected to the condenser and is adapted to circulate the liquid working fluid to the recuperator and the heat exchanger in a closed-loop cycle.
[0011] In one or more implementations, the system further comprises an Organic Rankine Cycle (ORC) to recover the energy from the waste heat.
[0012] In one or more implementations, the recuperator is adapted to dynamically adjust a flow rate of the working fluid based on temperatures and compositions of the exhaust gases, to optimize heat exchange.
[0013] In one or more implementations, the expansion unit comprises a turbine, structurally coupled to a generator, and arranged to convert the mechanical energy into electrical energy.
[0014] In one or more implementations, the working fluid corresponds to a low boiling point organic compound to maximize energy recovery from low-temperature exhaust gases.
[0015] According to another aspect of the present disclosure, a method for recovering energy from waste heat is disclosed. The method comprises directing exhaust gases from an exhaust manifold of a dual fuel engine into a recuperator. The method further comprises preheating, in the recuperator, the working fluid using heat of the exhaust gases. Thereafter, the method comprises transferring, using a heat exchanger, additional waste heat from the exhaust gases to the preheated working fluid and vaporizing the working fluid in an evaporator positioned downstream of the heat exchanger. The method further comprises expanding, in an expansion unit, the vaporized working fluid to convert thermal energy of the vaporized working fluid into mechanical energy and condensing, using a condenser, the expanded working fluid into a liquid state. Furthermore, the method comprises circulating, using a pump, the liquid working fluid to the recuperator and the heat exchanger in a closed loop cycle.
[0016] In one or more implementations, the method further comprises utilizing an Organic Rankine Cycle (ORC) to recover the energy from the waste heat.
[0017] In one or more implementations, the method further comprises dynamically adjusting, through the recuperator, a flow rate of the working fluid based on temperatures and compositions of the exhaust gases, to optimize heat exchange.
[0018] In one or more implementations, the expanding the vaporized working fluid comprises operating a turbine structurally coupled to a generator, to convert mechanical energy into electrical energy.
[0019] To further clarify the advantages and features of the method and system, a more particular description of the method and system will be rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The accompanying drawings constitute a part of the description and are used to provide a further understanding of the present invention. Such accompanying drawings illustrate the embodiments of the present invention used to describe the principles of the present invention. The embodiments are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which references indicate similar elements. It should be noted that references to "an" or "one" embodiment in this invention are not necessarily to the same embodiment, and they mean at least one. In the drawings:
[0021] FIG. 1 illustrates a block diagram depicting a schematic representation of a waste heat recovery system for dual fuel engines using a Recuperative Organic Rankine Cycle (ORC), in accordance with an embodiment of the present disclosure.
[0022] FIG. 2 illustrates a flowchart depicting a method for recovering waste heat from the dual fuel engines, in accordance with an embodiment of the present disclosure.
[0023] Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the invention. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.
DETAILED DESCRIPTION OF THE INEVENTION
[0024] It should be understood at the outset that although illustrative implementations of embodiments are illustrated below, the system and method may be implemented using any number of techniques. The disclosure should in no way be limited to the illustrative implementations, drawings, and techniques illustrated below, including the exemplary design and implementation illustrated and described herein, but may be modified within the scope of the appended claims along with their full scope of equivalents.
[0025] The term "some" and "one or more" as used herein is defined as "one, or more than one, or all." Accordingly, the terms "one," "more than one," but not all" or "all" would all fall under the definition of "some." The term "some embodiments" or "one or more embodiments" may refer to one embodiment or several embodiments or all embodiments. Accordingly, the term "some embodiments" is defined as meaning "one embodiment, or more than one embodiment, or all embodiments."
[0026] The terminology and structure employed herein are for describing, teaching, and illuminating some embodiments and their specific features and elements and do not limit, restrict, or reduce the spirit and scope of the claims or their equivalents.
[0027] More specifically, any terms used herein such as but not limited to "includes," "comprises," "has," "have" and other grammatical variants thereof do not specify an exact limitation or restriction and certainly do not exclude the possible addition of one or more features or elements, unless otherwise stated, and must not be taken to exclude the possible removal of one or more of the listed features and elements, unless otherwise stated with the limiting language "must comprise" or "needs to include."
[0028] The term "unit" used herein may imply a unit including, for example, one of hardware, software, and firmware or a combination of two or more of them. The "unit" may be interchangeably used with a term such as logic, a logical block, a component, a circuit, and the like. The "unit" may be a minimum system component for performing one or more functions or may be a part thereof.
[0029] Unless otherwise defined, all terms, and especially any technical and/or scientific terms, used herein may be taken to have the same meaning as commonly understood by one having ordinary skill in the art. Embodiments will be described below in detail with reference to the accompanying drawings.
[0030] The present disclosure relates to a waste heat recovery system for dual fuel engines, designed to capture and convert waste heat into useful work, such as mechanical energy or electricity, using a Recuperative Organic Rankine Cycle (ORC). The waste heat recovery system is engineered to improve an overall efficiency of the dual fuel engines by recovering heat from exhaust gases, which would otherwise be lost, and converting the recovered heat into additional power. This not only reduces fuel consumption but also contributes to lowering emissions and increasing engine sustainability.
[0031] An aspect of the present disclosure is to provide an efficient waste heat recovery system for dual fuel engines using a Recuperative Organic Rankine Cycle (ORC) that converts waste heat into useful work or electricity. Another aspect of the present disclosure is to optimize a heat exchange process by incorporating a recuperator that preheats a working fluid, enhancing efficiency of the waste heat recovery system under varying exhaust gas conditions. A further aspect of the present disclosure is to reduce fuel consumption and emissions of the dual fuel engines by maximizing waste heat recovery from exhaust gases.
[0032] Another aspect of the present disclosure is to provide a waste heat recovery system capable of adapting to fluctuating exhaust gas temperatures and compositions, typical in dual fuel engine operations. Yet another aspect of the present disclosure is to increase overall power output of the dual fuel engines by converting waste heat into additional mechanical or electrical energy.
[0033] FIG. 1 illustrates a block diagram depicting a schematic representation of a waste heat recovery system 100 for dual fuel engines 118 using a recuperative Organic Rankine Cycle (ORC), in accordance with an embodiment of the present disclosure.
[0034] The waste heat recovery system 100 (hereinafter may also be referred to as a system 100) is designed for use with the dual fuel engines 118 (hereinafter may also be referred to as the dual fuel engine 118). The dual fuel engine 118 equipped with the recuperative ORC is designed to enhance the efficiency of the dual fuel engine 118 by recovering the waste heat and converting the waste heat into useful work or electricity. The dual fuel engine 118 operates by burning a combination of two fuels, typically diesel and natural gas. This combustion process generates power to drive the dual fuel engine 118 and produces a significant amount of the waste heat. The dual fuel engines 118 produce the exhaust gases during the combustion process, which are a source of waste heat. The exhaust gases contain thermal energy that can be captured and repurposed by the system 100. After combustion, the exhaust gases, which contain a large amount of thermal energy, are expelled from the dual fuel engine 118 via an exhaust manifold, which channels hot gases into the system 100. The exhaust manifold (not shown in FIG.1) serves as the entry point for a waste heat recovery process, ensuring that the high-temperature gases are efficiently captured and directed into the next stage.
[0035] The system 100 further includes a preheater 102, a recuperator 104, a heat exchanger 106, an evaporator 108, an expander 110 (such as a turbine), an electricity generation unit 112, a condenser 114, a pump 116, and an intercooler 120. The components of the system 100 are arranged in a closed-loop configuration that allows the working fluid to continuously circulate through the system 100, undergoing different thermodynamic processes to maximize energy recovery.
[0036] The preheater 102 is positioned downstream of the exhaust manifold of the dual fuel engine 118. The preheater 102 improves the efficiency of the system 100 by raising the temperature of the working fluid before it absorbs the heat from the exhaust gases in the heat exchanger 106. This reduces the amount of heat that must be extracted from the exhaust gases, thereby improving the overall energy heat transfer efficiency. The preheater 102 typically utilizes residual heat from the cooling systems or the intercooler 120 to precondition the working fluid. The preheater 102 helps in raising the temperature of the working fluid, making the heat exchange process more efficient in subsequent stages.
[0037] The recuperator 104 is fluidly connected to the heat exchanger 106 and preheats the working fluid by transferring residual heat from the exhaust gases before the working fluid enters the heat exchanger 106. The recuperator 104 helps to maximize energy efficiency by utilizing the remaining heat from the exhaust stream. The recuperator 104 plays a critical role in improving the thermodynamic efficiency of the ORC cycle. The recuperator 104 preheats the working fluid before the working fluid enters the heat exchanger 106, reducing the amount of additional heat needed to vaporize the fluid. This preheating step not only enhances the efficiency of the waste heat recovery system 100 but also ensures that the working fluid enters the heat exchanger 106 at an optimal temperature.
[0038] The recuperator 104 is particularly important for the system 100 operating with the dual fuel engine 118, where exhaust gas temperatures fluctuate due to changes in the fuel mixture. By dynamically adjusting the heat recovery process, the recuperator 104 ensures consistent performance and maximizes the recovery of the waste heat even under variable operating conditions.
[0039] The heat exchanger 106 is responsible for capturing thermal energy from the exhaust gases. As the exhaust gases flow through the heat exchanger 106, the working fluid absorbs the heat and is gradually heated to a higher temperature. This process transfers the energy from the exhaust gases to the working fluid, preparing it for vaporization in the next stage. In an implementation, the working fluid corresponds to an organic compound with a low boiling point.
[0040] The heat exchanger 106 is designed to accommodate varying exhaust gas temperatures and compositions, which are characteristic of the dual fuel engine 118. This adaptability is crucial for maintaining efficiency across different operating conditions, ensuring that the system 100 recovers waste heat even when the fuel mixture or load of the dual fuel engine 118 changes.
[0041] After passing through the recuperator 102, the preheated working fluid enters the evaporator 108, where it is vaporized using the heat extracted from the exhaust gases in the heat exchanger 106. The evaporator 108 is responsible for converting the liquid working fluid into a vapor state. The vaporized fluid contains high thermal energy, which can be harnessed to perform mechanical work.
[0042] In an implementation, the evaporator 108 is configured to handle low and medium temperature exhaust gases, making it suitable for use in the dual fuel engines 118. The organic working fluid, chosen for its low boiling point, allows the system 110 to efficiently capture the waste heat even when the exhaust gases are not at high temperatures.
[0043] Once the working fluid is vaporized, it is directed into the expander 110, which converts the thermal energy of the vaporized fluid into mechanical work. The expander 110 is typically a turbine that rotates as the high-pressure vapor expands through it. The mechanical work can be used to drive an external device, such as a generator, to produce electricity, or it can be used to supplement the power output of the dual fuel engine 118.
[0044] The expander 110 is coupled to the generator, for converting the waste heat into the electrical energy. This enables the system 100 to generate additional power, which can either be used to reduce the engine's fuel consumption or to provide electricity for other applications.
[0045] The electricity generation unit 112 is mechanically connected to the expander 110 and is responsible for converting the mechanical work produced by the turbine into the electrical energy. The generated electricity can either be stored batteries, or fed back into the electrical grid, depending on the application.
[0046] After expanding through the expansion unit 110, the working fluid is cooled and condensed in the condenser 114. The condenser 114 is responsible for rejecting the remaining heat from the working fluid, converting it back into its liquid state so that it can be reused in the system 100. In an embodiment, the rejected heat may be utilized for auxiliary heating purposes, such as cabin heating in automotive applications, or dissipated into the environment.
[0047] The condenser 114 is designed to operate efficiently even under varying ambient conditions, ensuring that the working fluid is cooled to a sufficient temperature to be pumped back into the system 100.
[0048] The pump 116 is adapted to circulate the liquid working fluid back to the recuperator 104 and the heat exchanger 106. The pump 116 maintains a consistent flow rate and pressure, ensuring that the working fluid continuously circulates through the system 100 without interruption. This closed-loop configuration enables the system 100 to operate efficiently over long periods, recovering waste heat and converting it into usable energy in a repetitive cycle.
[0049] The intercooler 120 helps to control the temperature of the working fluid and prevents overheating of the working fluid during the thermodynamic cycle. The intercooler plays a crucial role in enhancing the efficiency of the heat exchange process.
[0050] In waste heat recovery from the dual-fuel engine 118 equipped with the recuperative ORC, several thermodynamic and heat transfer equations are essential. These equations describe the behavior of energy transfer, efficiency, and system dynamics. Below are some key equations:
[0051] First Law of Thermodynamics (Energy Balance): The first law of thermodynamics for a closed system is applied to the engine and components of the ORC:
Q-W=?U …………(1)
wherein Q corresponds to the heat added to the system 100 (from waste heat), W is the work done by the system (output from the ORC), and ?U is the change in internal energy.
[0052] Heat Transfer Equation: For the heat exchanger 106, the rate of heat transfer can be calculated using:
Q=m?Cp?T ………..(2)
wherein m? is the mass flow rate of the working fluid, Cp is the specific heat capacity at constant pressure, and ?T is the temperature difference between the inlet and outlet.
[0053] Thermodynamic Efficiency of the ORC: The thermal efficiency of the ORC can be defined as:
?ORC=Qin/Wnet …………..(3)
wherein Wnet is the net Work output, and Qin is the heat input from the waste heat.
[0054] Carnot Efficiency: The Carnot efficiency provides the theoretical maximum efficiency for the cycle:
?Carnot=1-Thigh/Tlow
wherein Tlow is the temperature of the cold reservoir, and Thigh is the temperature of the hot reservoir (waste heat source).
[0055] Organic Rankine Cycle Process Equations: The ORC follows a series of thermodynamic processes similar to the standard Rankine cycle, with the working fluid (organic compound) undergoing evaporation, expansion, condensation, and pumping:
[0056] Evaporation (Heat Addition):
Qin=m?(h2-h1)
wherein h2 is the enthalpy after evaporation, and h1 is the enthalpy before evaporation.
[0057] Expansion (Work Output):
Wturbine=m?(h3-h2)
wherein h3 is the enthalpy after expansion in the turbine.
[0058] Condensation (Heat Rejection):
Qout=m?(h4-h3)
wherein h4 is the enthalpy after condensation.
[0059] Recuperator Effectiveness: In a recuperative ORC, the recuperator 104 recovers heat from the turbine exhaust and preheats the working fluid:
[0060] ?=Qactual/Qmax=Cmin(Tout,hot-Tin,cold)/Cmin(Tin,hot-Tin,cold)
[0061] wherein ? is the recuperator effectiveness, Cmin is the minimum heat capacity rate, and T values represent the temperatures at the heat exchanger inlets and outlets.
[0062] Heat Transfer in Recuperator 104: The heat transfer rate in the recuperator 104 is given by:
Qrecup = m?recup Cp(Tin,recup-Tout,recup)
[0063] These equations describe the energy flow and efficiency in the waste heat recovery system with a dual-fuel engine coupled to an ORC. Key parameters include mass flow rates, temperature differences, and heat exchanger effectiveness, all of which are crucial for optimizing the system's performance.
[0064] FIG. 2 illustrates a flowchart depicting a method 200 for recovering the waste heat from the dual fuel engines, in accordance with an embodiment of the present disclosure. The method 200 comprises a series of steps 202 through 210. The method 200 starts at step 202.
[0065] At step 202, the method 200 comprises directing the exhaust gases from the exhaust manifold of the dual fuel engine 118 into the recuperator 102.
[0066] At step 204, the method 200 comprises preheating, in the recuperator 102, the working fluid using the heat of the exhaust gases.
[0067] At step 206, the method 200 comprises transferring, using the heat exchanger 106, additional waste heat from the exhaust gases to the preheated working fluid.
[0068] At step 208, the method 200 comprises vaporizing the working fluid in the evaporator 108 connected to the heat exchanger 106.
[0069] At step 210, the method 200 comprises expanding, in the expansion unit 110, the vaporized working fluid to convert thermal energy of the vaporized working fluid into mechanical energy.
[0070] At step 212, the method 200 comprises condensing, using the condenser 114, the expanded working fluid into the liquid state.
[0071] At step 214, the method 200 comprises circulating, using the pump 116, the liquid working fluid to the recuperator 104 and the heat exchanger 106 in the closed loop cycle.
[0072] The integration of the ORC cycle with the dual fuel engine 118 allows for the efficient use of waste heat that would otherwise be lost. By converting this waste heat into additional power or electricity, the overall efficiency of the engine is significantly improved. The system 100 is designed to adapt to varying exhaust gas temperatures and compositions, which are characteristic of the dual fuel engines 118. This adaptability ensures consistent performance under different operating conditions. By recovering the waste heat, the system 100 reduces the engine's overall fuel consumption, leading to cost savings. The present disclosure enables improved efficiency resulting in lower fuel usage, which in turn reduces the engine's emissions, contributing to environmental sustainability. Further, the additional power generated by the ORC cycle of the system 100 can be used to enhance the engine's overall power output or to provide electrical power for other systems.
[0073] The descriptions of the various embodiments of the present invention have been presented for purposes of illustration but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the embodiments described. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.
[0074] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one more other features, integers, steps, operations, element components, and/or groups thereof.
[0075] The flow diagrams depicted herein are just one example. There may be many variations to this diagram, or the steps (or operations) described therein without departing from the spirit of the invention. For instance, the steps may be performed in a differing order, or steps may be added, deleted, or modified. All of these variations are considered a part of the claimed invention.
[0076] While the preferred embodiment of the invention has been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described.
[0077] Those skilled in the art will appreciate that the methodology described herein in the present disclosure may be carried out in other specific ways than those set forth herein in the above disclosed embodiments, without departing from essential characteristics and features of the present invention. The above-described embodiments are therefore to be construed in all aspects as illustrative and not restrictive.
[0078] The drawings and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processed described herein may be changed and not limited to the manner described herein. Any combination of the above features and functionalities may be used in accordance with one or more embodiments.
[0079] In the present disclosure, each of the embodiments has been described with reference to numerous specific details, which may vary from embodiment to embodiment. The foregoing description of the specific embodiments disclosed herein may reveal the general nature of the embodiments herein that others may, by applying current knowledge, readily modify and/or adapt for various applications of such specific embodiments without departing from the generic concept, and therefore such adaptations and modifications are intended to be comprehended within the meaning of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and is not limited in scope.
, Claims:We Claim:

1. A system for recovering energy from waste heat, comprising:
a recuperator fluidly connected to an exhaust manifold of a dual fuel engine, the recuperator adapted to preheat a working fluid using heat of exhaust gases from the dual fuel engine;
a heat exchanger fluidly connected to the recuperator, the heat exchanger adapted to transfer additional heat from the exhaust gases to the preheated working fluid;
an evaporator fluidly connected to the heat exchanger, the evaporator adapted to vaporize the preheated working fluid using the heat received from the heat exchanger;
an expansion unit fluidly connected to the evaporator, the expansion unit adapted to cause an expansion of the vaporized working fluid and convert thermal energy into mechanical energy;
a condenser fluidly connected to the expansion unit, the condenser adapted to condense the expanded working fluid into a liquid state; and
a pump fluidly fluidly connected to the condenser, the pump adapted to circulate the liquid working fluid to the recuperator and the heat exchanger in a closed-loop cycle.

2. The system as claimed in claim 1, further comprising an Organic Rankine Cycle (ORC) to recover the energy from the waste heat.

3. The system as claimed in claim 1, wherein the recuperator is adapted to dynamically adjust a flow rate of the working fluid based on temperatures and compositions of the exhaust gases, to optimize heat exchange.

4. The system as claimed in claim 1, wherein the expansion unit comprises a turbine, structurally coupled to a generator, and arranged to convert the mechanical energy into electrical energy.

5. The system as claimed in claim 1, wherein the working fluid corresponds to a low boiling point organic compound to maximize energy recovery from low-temperature exhaust gases.

6. A method for recovering energy from waste heat, the method comprising:
directing exhaust gases from an exhaust manifold of a dual fuel engine into a recuperator;
preheating, in the recuperator, the working fluid using heat of the exhaust gases;
transferring, using a heat exchanger, additional waste heat from the exhaust gases to the preheated working fluid;
vaporizing the working fluid in an evaporator positioned downstream of the heat exchanger;
expanding, in an expansion unit, the vaporized working fluid to convert thermal energy of the vaporized working fluid into mechanical energy;
condensing, using a condenser, the expanded working fluid into a liquid state; and
circulating, using a pump, the liquid working fluid to the recuperator and the heat exchanger in a closed loop cycle.

7. The method as claimed in claim 6, further comprising utilizing an Organic Rankine Cycle (ORC) to recover the energy from the waste heat.

8. The method as claimed in claim 6, further comprising dynamically adjusting, through the recuperator, a flow rate of the working fluid based on temperatures and compositions of the exhaust gases, to optimize heat exchange.

9. The method as claimed in claim 6, wherein the expanding the vaporized working fluid comprises operating a turbine structurally coupled to a generator, to convert mechanical energy into electrical energy.

10. The method as claimed in claim 6, wherein the working fluid corresponds to a low boiling point organic compound to maximize energy recovery from low-temperature exhaust gases.

Dated this 30th day of October, 2024

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