DESC:TECHNICAL FIELD
[001] The present disclosure generally relates to fire heaters. Particularly, the present disclosure relates to a method and apparatus for performing real-time optimization of fired heaters. 5
BACKGROUND
[002] The following description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or 10 implicitly referenced is prior art.
[003] Fired heaters are crucial for heating process fluids in various industrial applications, and their operation typically incurs a significant fuel cost. In continuous operating plants, the fired heaters are often operated with fixed parameters or with parameters that require minimal adjustments based on existing control loops. However, there are numerous overlooked 15 parameters that, if optimized, could lead to substantial returns. By utilizing real-time analysis and established engineering practices, the fired heater system may focus on these parameters to identify opportunities for more efficient operation. This optimization can result in reduced fuel consumption and greenhouse gas emissions.
[004] Over time, operating conditions for the fired heaters deviate significantly from their 20 design parameters. If the operating team fails to adjust the parameters based on these deviations, it may result in several problems. Firstly, the fired heater may start consuming more fuel than necessary, leading to increased operating costs, and negatively impacting the plant's profitability and competitiveness. Secondly, inefficient operation of the fired heater also contributes to environmental issues by increasing the emissions of greenhouse gases and other 25 pollutants. Thirdly, the performance of the fired heater deteriorates over time, which leads to reduced reliability and increased maintenance requirements, thereby increasing operating costs and reducing overall plant efficiency. To address these limitations, there is a need for a system/apparatus that regularly monitors and optimizes the fired heater operations by adjusting parameters based on the operating conditions. 30
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SUMMARY
[005] The present disclosure overcomes one or more shortcomings of the prior art and provides additional advantages discussed throughout the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a 5 part of the claimed disclosure.
[006] In an aspect, the present disclosure may recite method for real-time optimization of fired heater. The method may include receiving one or more input parameters associated with one or more operations of the fired heater. The method may further include analyzing the one or more input parameters based on operating condition of the fired heater. The method may 10 further include determining, based on the analyzed one or more input parameters, a set of output parameters impacting performance of the fired heater. Finally, the method may include controlling the one or more optimizing tasks, based on the set of output parameters, to improve the performance of the fired heater.
[007] In another aspect, the present disclosure recites that the one or more input 15 parameters may correspond to fuel specification, fuel flow rate, excess air, ambient condition, and process variation.
[008] In another aspect, the present disclosure recites that the operating condition of the fired heater may be selected from the condition of the fired heater present at current time or the condition available at any historical period post designing of the fired heater. 20
[009] In another aspect, the present disclosure recites that the set of output parameters may correspond to excess air, flue gas exit temperature, air preheater bypass damper settings, and stack damper opening.
[0010] In another aspect, the present disclosure recites that the one or more optimizing tasks may be selected from at least one of fired heater leakage, fired heater tuning, equipment 25 protection, and identification of potential heat recovery.
[0011] In another aspect, the present disclosure recites a method of controlling one or more optimizing tasks of the fired heater that may include identifying at least one safe operating condition when the set of output parameters is determined to be present within a predefined range. The method further may include storing the one or more input parameters and 30 corresponding set of output parameters during the safe operating condition.
[0012] In another aspect, the present disclosure recites a method of controlling one or more optimizing tasks of the fired heater that may include identifying at least one unsafe operating condition when the set of output parameters may be determined to be present outside a
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predefined range. The method may further include generating an alert or action summary for an operator of the fired heater to take necessary measures for controlling the one or more optimizing tasks.
[0013] In an aspect, the present disclosure recites an apparatus for real-time optimization of a fired heater. The apparatus may comprise one or more sensors configured to sense and 5 provide one or more input parameters associated with one or more operations of the fired heater. The apparatus may further comprise a processing unit coupled to the one or more sensors and configured to receive the one or more input parameters associated with the one or more operations of the fired heater. Sequentially, the processing unit may be further configured to analyze the one or more input parameters based on operating condition of the fired heater 10 and determine, based on the analyzed one or more input parameters, a set of output parameters impacting the performance of the fired heater. Furthermore, the processing unit may be configured to control the one or more optimizing tasks, based on the set of output parameters, to improve the performance of the fired heater.
[0014] In another aspect, the one or more sensor units may be further configured to receive 15 reflected signal from the at least one object based on the signal transmitted to the at least one object. The frequency information may be associated with the frequency of the transmitted signal and the frequency of the reflected signal. The time information may be associated with a time at which the signal may be transmitted and a time at which the reflected signal may be received. Particularly, the one or more sensor units may sense a specific parameter for which 20 the sensor is designed, and it may provide the sensed and measured value to the system for further operations.
[0015] In another aspect, the present disclosure recites that the one or more input parameters may correspond to fuel specification, fuel flow rate, excess air, ambient condition, and process variation. 25
[0016] In another aspect, the present disclosure recites the processing unit may be configured to select the operating condition of the fired heater from either the condition of the fired heater present at current time or the condition available at any historical period post designing of the fired heater.
[0017] In another aspect, the present disclosure recites that the set of output parameters 30 may correspond to excess air, flue gas exit temperature, air preheater bypass damper settings, and stack damper opening.
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[0018] In another aspect, the present disclosure recites the processing unit that may be configured to select the one or more optimizing tasks from at least one of fired heater leakage, fired heater tuning, equipment protection, and identification of potential heat recovery.
[0019] In another aspect, the present disclosure recites that to control the one or more optimizing tasks of the fired heater the processing unit that may be further configured to 5 identify at least one safe operating condition when the set of output parameters are determined to be present within a predefined range. The processing unit may be further configured to store the one or more input parameters and corresponding set of output parameters during the safe operating condition.
[0020] In another aspect, the present disclosure recites that to control the one or more 10 optimizing tasks of the fired heater the processing unit that may be further configured to identify at least one unsafe operating condition when the set of output parameters may be determined to be present outside a predefined range. The processing unit may be further configured to generate an alert or action summary for an operator of the fired heater to take necessary measures for controlling the one or more optimizing tasks. 15
[0021] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. 20
BRIEF DESCRIPTION OF DRAWINGS
[0022] The embodiments of the disclosure itself, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings. One or more embodiments are now described, by way of example 25 only, with reference to the accompanying drawings in which:
[0023] FIG. 1 illustrates a schematic arrangement of a fired heater, in accordance with an embodiment of the present disclosure.
[0024] FIG. 2 illustrates by way of a block diagram of an apparatus for real-time optimization of a fired heater, in accordance with an embodiment of the present disclosure. 30
[0025] FIG. 3 illustrates by way of a block diagram of optimization of a task related to fired heater tuning, in accordance with an embodiment of the present disclosure.
[0026] FIG. 4 illustrates by way of a block diagram of optimization of a task related to fired heater leakage, in accordance with an embodiment of the present disclosure.
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[0027] FIG. 5 illustrates by way of a block diagram of optimization of a task related to equipment protection, in accordance with an embodiment of the present disclosure.
[0028] FIG. 6 illustrates by way of a block diagram of optimization of a task related to the identification of potential heat recovery, in accordance with an embodiment of the present disclosure. 5
[0029] FIG. 7 illustrates by way of block diagram of an apparatus for controlling the one or more optimizing tasks of the fired heater, in accordance with an embodiment of the present disclosure.
[0030] FIG. 8 a flow diagram illustrating a method for real-time optimization of a fired heater, in accordance with an embodiment of the present disclosure. 10
[0031] The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION 15
[0032] The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. 20
[0033] Various embodiments of the present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will satisfy applicable legal 25 requirements. The term “or” is used herein in both the alternative and conjunctive sense, unless otherwise indicated. The terms “illustrative,” “example,” and “exemplary” are used to be examples with no indication of quality level. Like numbers refer to like elements throughout.
[0034] The phrases “in an embodiment,” “in one embodiment,” “according to one embodiment,” and the like generally mean that the particular feature, structure, or characteristic 30 following the phrase may be included in at least one embodiment of the present disclosure and may be included in more than one embodiment of the present disclosure (importantly, such phrases do not necessarily refer to the same embodiment).
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[0035] The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations.
[0036] If the specification states a component or feature “can,” “may,” “could,” “should,” “would,” “preferably,” “possibly,” “typically,” “optionally,” “for example,” “often,” or 5 “might” (or other such language) be included or have a characteristic, that particular component or feature is not required to be included or to have the characteristic. Such component or feature may be optionally included in some embodiments, or it may be excluded.
[0037] Disclosed herein is an apparatus for real-time optimization of a fired heater. The apparatus may comprise one or more sensors configured to sense and provide one or more input 10 parameters associated with one or more operations of the fired heater. The apparatus may further comprise a processing unit coupled to the one or more sensors and configured to receive the one or more input parameters associated with the one or more operations of the fired heater. Sequentially, the processing unit may be further configured to analyze the one or more input parameters based on operating condition of the fired heater and determine, based on the 15 analyzed one or more input parameters, a set of output parameters impacting the performance of the fired heater. Furthermore, the processing unit may be configured to control the one or more optimizing tasks, based on the set of output parameters, to improve the performance of the fired heater. Thus, the apparatus may provide efficient and reliable performance of the fired heater, while also reducing fuel consumption, emissions, and maintenance costs of the fired 20 heater. Additionally, the apparatus may provide saving on fuel, carbon based on the best achievable conditions, which in turn leads to economic advantage as well. Additionally, the apparatus may provide reconciliation of instrument accuracy, such as the oxygen analyzer etc.
[0038] Turning now to the drawings, the detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not 25 intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts with like numerals denote like components throughout the several views. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. 30
[0039] FIG. 1 illustrates a schematic arrangement of a fired heater 100. The fired heater 100 may consist of a radiation section 102, a convection section 104, a stack or draft section 106 and an air pre-heater (APH) system 108.
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[0040] The radiation section 102 may be a section where the heat may be generated by the fuel combustion. The convection section 104 may be a section where the heat is transferred from hot combustion gases to the process fluid through the heat transfer surface. This section may be typically located above the radiation section 102 and may consist of a series of tubes or finned tubes that may provide a large heat transfer area. The stack section 106 may be 5 responsible for maintaining the draft in the fired heater 100 and releasing the flue gases into the atmosphere. The APH system 108 may consist of a heat exchanger that may preheat the combustion air before the combustion air may enter a burner in the radiation section 102. The combustion air may pass through the tubes of the heat exchanger, while the hot flue gases may surround the tubes. These sections of the fired heater all together may provide efficient transfer 10 of heat from the combustion gases to the process fluid in the fired heater 100 while minimizing fuel consumption and emissions.
[0041] To maintain efficient and optimal performance of the fired heater 100, certain parameters must be closely monitored and controlled. In particular, the various sections of the fired heater are closely related to the parameters that may be monitored and controlled in order 15 to maintain efficient and optimal performance of the heater.
[0042] These parameters may play a crucial role in optimizing the fired heater performance efficiently. These parameters may be, not limited to, feed inlet temperature, pressure, and flowrate, process absorbed duty, feed outlet temperature, pressure, and flowrate, excess O2%, flue gas (FG) temperature ex-APH, cold end tube metal temperature (TMT), 20 forced draft (FD) fan, an induced draught (ID) fan, bypass damper opening, stack temperature, fuel temperature, and so forth. The forthcoming paragraphs provide an overview related to the parameters.
[0043] For example, the feed inlet temperature, pressure, and flowrate may represent a condition of the process fluid entering the fired heater 100. The feed inlet temperature and 25 pressure may be important for designing a heat transfer surface and a burner system in the fired heater 100. The flowrate may determine the amount of heat that needs to be transferred to the process fluid.
[0044] The process absorbed duty may be amount of heat that may be transferred from the hot combustion gases to the process fluid. This value may depend on the inlet temperature and 30 desired outlet temperature of the process fluid and the flowrate.
[0045] The feed outlet temperature, pressure, and flowrate may be related to the condition of the process fluid leaving the fired heater 100. The feed outlet temperature and pressure may be maintained within a specified range to meet the process requirements.
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[0046] The excess O2% may be an amount of oxygen present in the combustion gases. This value may be an indicator of the combustion efficiency and may be used to optimize the fuel consumption and reduce emissions.
[0047] The FG temperature ex-APH may be temperature of the combustion gases leaving the APH system 108. This value may be maintained within a specified range to ensure the 5 efficient operation of the APH system 108.
[0048] The cold end TMT may be a tube metal temperature of the coldest end of the metallic air preheater. This value may be maintained above dew point to avoid corrosion.
[0049] The FD Fan may be used to provide the required airflow for the combustion process. The FD fan may be designed to provide the required pressure and flowrate to meet the 10 process requirements.
[0050] The ID fan may be used to aid exhaust of flue gas through stack and to maintain draft.
[0051] The bypass damper opening may be used to control the flow of cold air to the APH system. The bypass damper opening may be adjusted to maintain the required temperature of 15 the combustion at the exit of the air preheater.
[0052] The stack temperature may be temperature of the flue gases leaving the fired heater 100. This value may be maintained within a specified range to ensure the efficient operation of the fired heater 100 and to minimize emissions.
[0053] The fuel temperature, pressure, flowrate may be related to the condition of the fuel 20 entering the fired heater 100. The fuel temperature and pressure may be important for designing the burner system, while the flowrate may determine the amount of fuel that needs to be supplied to meet the process requirements.
[0054] In the traditional process of operating the fired heater 100, a set of parameters are selected without considering the operating conditions. This approach results in inefficiencies 25 and problems such as increased fuel consumption, higher operating costs, and negative impact on the environment. To overcome these limitations, an apparatus for real-time optimization of fired heater is disclosed that may regularly monitor and optimize fired heater operations and is capable of recommending adjustments of the parameters based on real-time operating conditions. The detailed explanation of the functioning of the apparatus is further explained 30 from the Fig. 2.
[0055] FIG. 2 illustrates an apparatus 200 for real-time optimization of fired heater (same as the system 100 of Fig. 1), in accordance with an embodiment of the present disclosure. According to an embodiment of the present disclosure, the apparatus 200 may comprise one or
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more sensors 202 and a processing unit 204. All the elements of the apparatus 200 illustrated in FIG. 2 are essential elements, but the apparatus 200 may also be implemented by the elements other than the elements illustrated in FIG. 2, however the same is not explained for the sake of brevity. All the elements of the apparatus 200 may communicate with each other via wireless/wired communication network. 5
[0056] Further, the processing unit 204 may be constituted by an analyzing unit 206, a determination unit 208, and a control unit 210. All the elements included in the processing unit 204, illustrated in FIG. 2 are essential elements; however, a skilled person may include additional components in the processing unit 204 other than the elements illustrated in FIG. 2. However, the same is not explained for the sake of brevity. All the elements of the processing 10 unit 204 may communicate with each other via wireless/wired communication network.
[0057] In a non-limiting embodiment of the present disclosure, one or more sensors 202 may be configured to sense and provide one or more input parameters associated with one or more operations of the fired heater 100. The one or more input parameters may correspond to fuel specification, fuel flow rate, excess air, ambient condition, and process variation. 15
[0058] In particular, the one or more sensors 202 may be installed at various locations in or around the fired heater 100. The one or more sensors 202 may be, not limited to, temperature sensor(s), pressure sensor(s), flow sensor(s), level sensor(s), gas composition sensor(s), and combination of multiple sensor(s). The one or more sensors 202 may be designed to sense or measure one or more physical or chemical parameters that may be associated with the fired 20 heater operation.
[0059] For example, the one or more sensors 202 may measure the type of fuel being used in the fired heater 100 and its properties, e.g., sulphur content. The one or more sensors 202 may detect a fuel changeover. Additionally, the one or more sensors 202 may measure oxygen content in flue gas exiting the fired heater 100, which may be used to calculate the excess air 25 required for the fired heater 100. The excess air may correspond to the amount of air that may be supplied to the fired heater 100 in addition to the amount required to ensure complete combustion. Additionally, the one or more sensors 202 may measure relative humidity, relevant environmental parameters, and ambient temperature around the fired heater 100. Additionally, the one or more sensors 202 may measure parameters related to process variation. The process 30 variation may refer to any changes in the conditions or parameters of the process being performed by the fired heater 100. For example, if the flow rate or temperature of the process fluid changes, this may affect the performance of the fired heater 100.
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[0060] In a non-limiting embodiment of the present disclosure, the processing unit 204 may be configured to receive the one or more input parameters associated with the one or more operations of the fired heater 100.
[0061] In particular, after sensing the information related to the input parameters, the one or more sensors 202 may provide the input parameters to the analyzing unit 206. The analyzing 5 unit 206 may receive the fuel specifications (such as fuel sulphur content or fuel changeover), fuel flow rate, excess air, ambient conditions (such as temperature and humidity), and process variation from the one or more sensors 202.
[0062] In an alternative embodiment, the input parameters may be received manually by an operator or technician. Particularly, the operator or technician may physically measure and 10 record the values of the various parameters using instruments. The instruments may be, not limited to, flow meters, thermometers, pressure gauges, gas analyzers, and so forth. After measuring the parameters, the operator or technician may provide the parameters as the input parameters to the processing unit 204.
[0063] In a non-limiting embodiment of the present disclosure, the analyzing unit 206 may 15 be configured to select the operating condition of the fired heater 100 from either condition of the fired heater 100 present at current time or condition available at any historical period post designing of the fired heater 100. After that the analyzing unit 206 may be configured to analyze the one or more input parameters based on the selected operating condition of the fired heater 100. 20
[0064] In particular, the selection of the operating condition for analysis of input parameters may be performed based on the requirements of the real-time optimization process. The analyzing unit 206 may select the operating condition of the fired heater from either the current state of the fired heater or based on any historical data available after the design of the fired heater. The operating condition may be, not limited to, heater outlet temperature, heater 25 outlet pressure, heater firing rate, combustion air temperature, furnace draft, and so forth.
[0065] In order to select the current operating condition of the fired heater, the analyzing unit 206 may analyze the output from one or more sensors 202 which provide information about the current state of the fired heater 100, such as the temperature, pressure, and fuel flow rate, ambient condition, excess air, current efficiency of the fired heater 100, and process 30 variation etc. Based on this information, the analyzing unit 206 may determine the current operating condition of the fired heater 100 and use it to analyze the input parameters.
[0066] In an exemplary embodiment, the analyzing unit 206 selects parameters form a historical period as an operating condition of the fired heater 100. The analyzing unit 206 may
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analyze past performance of the fired heater based on certain parameters, to determine the appropriate operating condition for the current process. This may involve analyzing data such as temperature profiles, fuel consumption, and process variables from previous operation of the fired heater. The analyzing unit 206 may use this as historical data to identify historical operating condition post designing of the fired heater 100. 5
[0067] After selecting the operating condition, the analyzing unit 206 may analyze the input parameters based on the selected operating condition. The analyzing unit 206 may include a model that may perform analysis of the input parameters of the fired heater 100. The Model may be, not limited to, First-principles models, Empirical models, Hybrid models, and so forth. In particular, the analyzing unit 206 may identify expected values of each of the input 10 parameters for the selected operating condition. These expected values may be determined during the design phase of the fired heater 100 and may be based on factors such as the fired heater size, capacity, and so forth. Once the expected values may be identified, the analyzing unit 206 may compare the expected value to actual values of each input parameter. If there is a deviation between the expected and actual values, this indicates that there may be an issue 15 with the fired heater's performance or with an instrument that measures one or more parameters related to fired heater’s performance.
[0068] For example, if the expected fuel flow rate for a given operating condition is 10 Kg per hour, but the actual flow rate being sensed by the fuel flow rate sensor is 8 Kg per hour, in such scenario, the analyzing unit 206 may identify this as an issue with the fuel flow rate and 20 may try to analyze the factors responsible for fuel flow rate.
[0069] In a non-limiting embodiment of the present disclosure, the determining unit 208 may be configured to determine, based on the analyzed one or more input parameters, a set of output parameters impacting the performance of the fired heater 100. The set of output parameters corresponds to excess air, flue gas exit temperature, air preheater bypass damper 25 settings and stack damper opening.
[0070] In particular, the determination unit 208 may receive the analysis result from the analyzing unit 206. After receiving the analysis result, the determination unit 208 may determine deviation from the expected values. This deviation may be used to determine the corresponding impact on the set of output parameters. 30
[0071] For example, if the fuel flow rate is lower than the expected value, this may result in a higher excess air value, as less fuel is being burned and more air may be present in the combustion process. This, in turn, may impact the flue gas exit temperature and air preheater
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bypass damper settings, as the higher value of excess air may lower the heater efficiency and require adjustments to the air preheater bypass damper settings.
[0072] In a non-limiting embodiment of the present disclosure, the control unit 210 may be configured to control the one or more optimizing tasks, based on the set of output parameters, to improve the performance of the fired heater. The one or more optimizing tasks 5 may be fired heater leakage, fired heater tuning, equipment protection and identification of potential heat recovery. The controlling of the optimizing tasks of the fired heater 100 may be further explained in fig. 7 in forthcoming paragraphs. Further, how these tasks may be affected based on input parameters is further explained in Figs. 3-6 in forthcoming paragraphs.
[0073] Fig. 3 discloses the optimization of a task of fired heater tuning. The optimization 10 task of fired heater tuning 300 may be performed by an apparatus 302 (same as the apparatus 200 of Fig. 2) based on the input parameters and their affecting output parameters. The affecting output parameters may be, not limited to, by-pass damper regulation, FD fan regulation, and so forth. The forthcoming paragraphs may explain how each output parameter may be affected by at least one of the input parameters. 15
[0074] For example, the bypass damper regulation may be affected by multiple input parameters. A detailed explanation of how the input parameters may affect the by-pass damper regulation is explained in upcoming paragraphs.
[0075] Fuel oil flow and specifications, and fuel gas flow and specifications may affect the combustion process and, in turn, the flue gas temperature and acid dew point. APH bypass 20 damper serves a critical function in ensuring that the flue gas temperature coming out from the APH is at its optimum level. In case the flue gas coming out from APH is too high, it may lead to valuable energy going out of the stack and wastage of energy. Conversely, if the flue gas temperature coming out of APH is very low, it may lead to acid corrosion issues in the downstream equipment which again lead to loss in production time and associated costs for 25 critical equipment replacement. Thus, controlling and modulation of the APH bypass damper helps in operating the heater at an optimized cost.
[0076] Further, for the FD fan regulation which may be affected by multiple input parameters. The detailed explanation of how the input parameters may affect the FD fan regulation may be explained in upcoming paragraphs. 30
[0077] FD Fans are required to be modulated to control the amount of air being fed to the furnace to ensure proper combustion of fuel. In general, fired heaters operate at 15-25% of excess air than that stoichiometrically required. This is to ensure that complete fuel is properly combusted and there are no incombustibles. Incombustibles in flue gas lead to valuable fuel
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wastage. Proper combustion is monitored through oxygen analyzers and CO analyzers fitted on the furnace. In case the amount of air is not adequate, the oxygen analyzer reads lower value than that desired and accordingly fan speed has to be increased to send more air. Conversely, if the amount of oxygen reading is very high, it indicates that more than required air is sent to the furnace and accordingly, FD fan speed has to be reduced to reduce the amount of air being 5 fed to the furnace. The excess air impacts the efficiency calculation heavily. CO analyzer works in converse way to the oxygen analyzer.
[0078] Moving towards Fig. 4 which may disclose the optimization of a task related to fired heater leakage. The optimization of a task related to fired heater leakage 400 may disclose the optimization performed by an apparatus 402 (same as the apparatus 200 of Fig. 2) based on 10 the input parameters and their affecting output parameters. The affecting output parameters may be, not limited to, Air flow through APH, Air flow through bypass damper, flue gas flow through APH, flue gas flow through Stack Damper, and so forth.
[0079] The air flow through the APH may be affected by a number of factors. APH choking due to fallen off pieces can impact the air flow as that induces additional resistance in 15 the circuit. Similarly, in case the APH bypass damper is kept open inadvertently, some of the air may bypass the APH and thus, lower air flows through the APH and lower heat is recovered from the outgoing flue gas.
[0080] Additionally, the air flow through the bypass damper determines the air temperature going to the burners. Partial open bypass damper shall cause the cold air to mix 20 with hot air coming out of APH and the resultant air temperature will be lower than that just at the exit of the APH.
[0081] Additionally, the flue gas flow and heat recovery through APH may be influenced by the level of heat recovery permitted by the flue gas sulphur dew point conditions. Partial opening of bypass damper helps in maintaining the APH and downstream metallic components 25 above its dew point level, whereas closing of bypass damper ensures that maximum heat is recovered, and highest efficiency is attained.
[0082] The flue gas damper at stack in case of balanced draft operation remains 100% close in case of normal operation. The function of this damper in balanced draft mode is to divert the flue gas to the APH system and prevent any flue gas bearing valuable heat from 30 escaping out of the system. In case of an upset in the APH system, the stack damper is fully opened to permit the heater to run on forced draft mode and draft for pulling out the flue gas is being created by the stack.
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[0083] Fig. 5 discloses the optimization of a task related to equipment protection. The optimization of a task related to equipment protection 500 may disclose the optimization performed by an apparatus 502 (same as the apparatus 200 of Fig. 2) based on the input parameters and their affecting output parameters. The affecting output parameters may be, not limited to, APH bypass damper regulation, FD fan regulation, and so forth. The forthcoming 5 paragraphs may explain how each output parameter may be affected by at least one of the input parameters.
[0084] The APH bypass damper regulation may be affected by the flue gas S-dew point, flue gas ex-APH temperature, APH cold-end metal temperature, CO analyzer, O2 analyzer, and flame detection status. For example, Flue gas S-dew point may affect the APH bypass damper 10 regulation for ensuring that the flue gas metallic components in the flue gas always remain above the sulphur dew point. If the S-dew point is high due to high sulphur fuel, it may cause the condensation of sulfuric acid H2SO4in the flue gas, which may lead to corrosion in the APH. This can be prevented through the bypass damper to open up to avoid corrosion. The flue gas ex-APH temperature may affect the bypass damper regulation as it may provide an 15 indication of the heat transfer rate from the flue gas to the APH. If the ex-APH temperature may be low, it can cause the bypass damper to open up to maintain the desired APH inlet temperature. The APH cold-end metal temperature may provide an indication of the heat transfer rate from the APH to the cold air. If the temperature may be high, it may cause the bypass damper to close to maintain the desired temperature at the flue gas outlet from the APH. 20
[0085] The FD fan may be affected by different parameters as described in the foregoing paragraphs and description of Fig. 3.
[0086] Fig. 6 discloses the optimization of a task related to the identification of potential heat recovery. optimization of a task related to the identification of potential heat recovery 600 may disclose the optimization performed by an apparatus 602 (same as the apparatus 200 of 25 Fig. 2) based on the input parameters and their affecting output parameters. The affecting output parameters may be, not limited to, augmentation of existing Convection Section/cast APH, retrofitting of new APH/outboard steam generator (OBSG), retrofitting of low temperature APH, combustion air distribution, burner fine-tuning/component replacement, arresting air-ingress, and so forth. The forthcoming paragraphs may explain how each output 30 parameter may be affected by at least one of the input parameters.
[0087] The augmentation of existing Convection Section/cast APH may be affected by the stack temperature and excess O2. A higher stack temperature and excess O2 may indicate that
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the existing convection section/cast APH may need to be augmented to improve heat transfer and reduce emissions.
[0088] Further, retrofitting of new APH/OBSG may be affected by the stack temperature and excess O2. A higher stack temperature and excess O2 may indicate that retrofitting a new APH or OBSG may be necessary to improve heat transfer and reduce emissions. 5
[0089] Further, retrofitting of low temperature APH may be affected by the amount of heat going out of the stack unused. Low temperature heat recovery options like glass air preheater (heat transfer surface made of corrosion resistant glass tubes) are generally preferred to exact the flue gas heat going out of the stack.
[0090] Further, combustion air distribution may be affected by excess O2, and module 10 optimized excess O2. A high excess O2 and module optimized excess O2 may indicate that the combustion air distribution needs to be adjusted to optimize combustion and reduce excess oxygen levels.
[0091] Further, burner fine-tuning / component replacement may be affected by excess O2, and module optimized excess O2. A high excess O2 and the module optimized excess O2 may 15 indicate that the burner needs to be fine-tuned or that certain components need to be replaced to improve combustion and reduce excess oxygen levels.
[0092] Further, arresting air-ingress may be affected by the excess O2, and the module optimized excess O2. A high excess O2 and the module optimized excess O2 may indicate that air-ingress needs to be arrested to improve combustion and reduce excess oxygen levels. 20
[0093] FIG. 7 illustrates an apparatus 700 (same as the apparatus 200 of Fig. 2) for real-time optimization of fired heater (such as the fired heater 100 of Fig. 1), in accordance with an embodiment of the present disclosure. As discussed in forgoing paragraphs in view of description of figure 2, the apparatus 700 may include a control unit 702 (same as the control unit 210 of Fig. 2) that may be configured to control the one or more optimizing tasks of the 25 fired heater 100. The elements of the control unit 702 may include one or more sub-units including but not limited to an identification unit 704, a memory module 706, and a generation unit 708. All the elements of the control unit 702 illustrated in FIG. 7 are essential constituent elements, and the control unit 702 may be implemented by more elements than the elements illustrated in FIG. 7, however the same is not explained for the sake of brevity. All the elements 30 of the control unit 702 may communicate with each other via wireless/wired communication network.
[0094] In a non-limiting embodiment of the present disclosure, the identification unit 704 may be configured to identify at least one safe operating condition when the set of output
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parameters are determined to be present within a predefined range. After that, the memory module 706 may be configured to store the one or more input parameters and corresponding set of output parameters during the safe operating condition.
[0095] In particular, the identification unit 704 may receive the set of the output parameters from the determination unit (such as the determination unit 208 of Fig. 2). After 5 that, the identification unit 704 may monitor the output parameters and compare them to a predetermined safe range. In an embodiment the predefined safe range for each of the output parameters may be stored in the memory module 706. The identification unit 704 may extract the predefined safe range from the memory module 706. In an alternative embodiment, the predefined safe may be provided by an operator/technician manually. After the comparison, if 10 the output parameters are determined to be within the predefined safe range, the identification unit 704 may identify that as a safe operating condition.
[0096] Additionally, the identification unit 704 may provide these output parameters and corresponding input parameters to the memory module 706. The memory module 706 may store the one or more input parameters and corresponding set of output parameters during the 15 safe operating condition for future reference. This information may be used to establish a baseline for future operations or to analyze the performance of the fired heater under safe operating conditions.
[0097] For example, the fired heater 100 may be operating with an input parameter of a fuel flow rate of 50 kg/h, and the output parameters being monitored may be the stack 20 temperature and excess oxygen level. The safe operating range for stack temperature may be between 250°C and 350°C, and for excess oxygen, it may be between 2% and 4%. If the identification unit 704 may determine that the stack temperature is 300°C and the excess oxygen level is 3%, the identification unit 704 may identify this as a safe operating condition because both output parameters may be within their respective safe ranges. In addition, the 25 identification unit may store the input parameter of the fuel flow rate at 50 kg/h and the corresponding set of output parameters (stack temperature of 300°C and excess oxygen level of 3%). Storing of the safe operating conditions may be helpful in training of the system so that based on the current operating conditions and the sensed values (obtained from sensors), at later stage, the system makes adjustment itself, in respect of selection of the parameters to 30 operate in safe conditions.
[0098] In a non-limiting embodiment of the present disclosure, the identification unit 704 may be configured to identify at least one unsafe operating condition when the set of output parameters is determined to be present outside a predefined range. After an operation of the
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identification unit, the generation unit 708 may be configured to generate an alert or action summary for an operator of the fired heater to take necessary measures for controlling the one or more optimizing tasks.
[0099] In particular, the identification unit 704 may receive the set of the output parameters from the determination unit 208. After that, the identification unit 704 may monitor 5 the output parameters of the fired heater 100 and compare them to a predefined range. If the set of output parameters may be outside the predefined range, the identification unit 704 may indicate an unsafe operating condition. After the identification of the unsafe operating condition, the identification unit 704 may provide an unsafe operation condition information to the generation unit 708. The generation unit 708, after receiving unsafe operation condition 10 information, may generate an alert or action summary for the operator/technician of the fired heater 100. The alert may be in the form of a visual or audible warning, or a message displayed by an apparatus on a screen (not shown in Fig. 7) of the apparatus 700. The action summary may suggest a required action to control the optimizing tasks and ensure the safety of the fired heater. 15
[00100] For example, the input parameters for a fired heater 100 may be fuel flow rate, air-to-fuel ratio, and temperature setpoint. The output parameters may be flame temperature (wherever required), flue gas flow rate, emissions, flue gas conditions and APH exit temperature. The apparatus 700 may continuously monitor these output parameters and compare them to predefined safe and unsafe ranges. For example, the safe range of flue gas 20 temperature generated by the mixture of a heavy sulphur fuel oil and low sulphur fuel gas is 120 oC, and the measured flue gas temperature is 115 oC. In that case, the optimizer ensures and warns that the equipment may face corrosion issues. Conversely, if the flue gas temperature is, say, 150 oC. Then the optimizer advises ways for further heat recovery through closure of the dampers. The generation unit may generate an alert or action summary for the operator of 25 the fired heater. The alert may be “Unsafe operating condition detected low excess air-may lead to unsafe operating condition. Please adjust the fuel flow rate or air-to-fuel ratio to bring the amount of air to required/expected value.” The operator may take the suggested actions to control the optimizing tasks and ensure safe and efficient operation of the fired heater. This may help in reducing the inspection time and may help in expediting the process of taking 30 corrective measures (also the shut down time of the plant gets reduced). The alert or warning message may be provided via the apparatus wirelessly as well so that the requirement of monitoring the operation of fired heater in the plant may be avoided.
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[00101] FIG. 8 is a flowchart showing steps of a method 800 for real-time optimization of fired heater (such as the fired heater 100 of Fig. 1) by an apparatus (such as an apparatus 200 of Fig. 2). The method starts at step 802,at a step 802 the method 800 may include receiving one or more input parameters associated with one or more operations of the fired heater. The one or more input parameters corresponds to fuel specification, fuel flow rate, excess air, 5 ambient condition, and process variation. In an exemplary aspect, one or more sensors 202 of Fig. 2 of an apparatus 200 of Fig. 2 may be configured to carry out the process steps disclosed in step 802.
[00102] At a step 804, the method 800 may include analyzing the one or more input parameters based on operating condition of the fired heater. The operating condition of the 10 fired heater is selected from the condition of the fired heater present at current time or condition available at any historical period post designing of the fired heater. In an exemplary aspect, an analyzing unit 206 of Fig. 2 of the apparatus 200 may be configured to carry out the process steps disclosed in step 804.
[00103] At a step 806, the method 800 may include determining, based on the analyzed one 15 or more input parameters, a set of output parameters impacting performance of the fired heater. The set of output parameters corresponds to excess air, flue gas exit temperature, air preheater bypass damper settings, targeted air flowrate, estimated level of O2 at arch, and stack damper. The method 800 may include displaying the set of output parameters. In an exemplary aspect, a determination unit 208 of the apparatus 200 may be configured to carry out the process steps 20 disclosed in step 806.
[00104] At a step 808, the method 800 may include controlling the one or more optimizing tasks, based on the set of output parameters, to improve the performance of the fired heater. The one or more optimizing tasks is selected from at least one of fired heater leakage, fired heater tuning, equipment protection and identification of potential heat recovery. The 25 controlling one or more optimizing tasks of the fired heater may include identifying at least one safe operating condition when the set of output parameters is determined to be present within a predefined range and storing the one or more input parameters and corresponding set of output parameters during the safe operating condition. The controlling one or more optimizing tasks of the fired heater may include identifying at least one unsafe operating 30 condition when the set of output parameters is determined to be present outside a predefined range and generating an alert or action summary for an operator of the fired heater to take necessary measures for controlling the one or more optimizing tasks. In an exemplary aspect,
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a control unit 210 of Fig. 2 of the apparatus 200 may be configured to carry out the process steps disclosed in step 808.
[00105] The method 800 may provide efficient and reliable performance of the fired heater, while also reducing fuel consumption, emissions, and maintenance costs of the fired heater. Additionally, the method 800 may provide calculation of potential fuel savings, carbon savings, 5 and monetary savings based on the best achievable conditions. Additionally, the method 800 may provide reconciliation of instrument accuracy, such as the oxygen analyzer.
[00106] The foregoing method descriptions and the process flow diagrams are provided merely as illustrative examples and are not intended to require or imply that the steps of the various embodiments must be performed in the order presented. As will be appreciated by one 10 of skill in the art the order of steps in the foregoing embodiments may be performed in any order. Words such as “thereafter,” “then,” “next,” etc. are not intended to limit the order of the steps; these words are simply used to guide the reader through the description of the methods. Further, any reference to claim elements in the singular, for example, using the articles “a,” “an” or “the” is not to be construed as limiting the element to the singular. 15
[00107] As used herein, the term unit may be implemented in hardware and/or in software. If the unit is implemented in hardware, the unit may be configured as a device, e.g., as a computer or as a processor or as a part of a system, e.g., a computer system. If the unit is implemented in software, the unit may be configured as a computer program product, as a function, as a routine, or as a program code. 20
[00108] The hardware used to implement the various illustrative logics, logical blocks, modules, and circuits described in connection with the aspects disclosed herein may include a general purpose processor, a digital signal processor (DSP), a special-purpose processor such as an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA), a programmable logic device, discrete gate or transistor logic, discrete hardware components, 25 or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but, in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction 30 with a DSP core, or any other such configuration. Alternatively, or additionally, some steps or methods may be performed by circuitry that is specific to a given function.
[00109] In one or more example embodiments, the functions described herein may be implemented by a web application or a web-based application. The web application may be an
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application that can be accessed through the web over a network (e.g., the Internet, etc.). The Web-based application may use a browser engine, such as found in a web browser engine, as an interface to the application server.
[00110] In one or more example embodiments, the functions described herein may be implemented by special-purpose hardware or a combination of hardware programmed by 5 firmware or other software. In implementations relying on firmware or other software, the functions may be performed as a result of execution of one or more instructions stored on one or more non-transitory computer-readable media and/or one or more non-transitory processor-readable media. These instructions may be embodied by one or more processor-executable software modules that reside on the one or more non-transitory computer-readable or 10 processor-readable storage media. Non-transitory computer-readable or processor-readable storage media may in this regard comprise any storage media that may be accessed by a computer or a processor. By way of example but not limitation, such non-transitory computer-readable or processor-readable media may include random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), FLASH 15 memory, disk storage, magnetic storage devices, or the like. Disk storage, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), and floppy disk, or other storage devices that store data magnetically or optically with lasers. Combinations of the above types of media are also included within the scope of the terms non-transitory computer-readable and processor-readable media. Additionally, any combination of 20 instructions stored on the one or more non-transitory processor-readable or computer-readable media may be referred to herein as a computer program product.
[00111] Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of teachings presented in the foregoing descriptions and the associated drawings. Although the 25 figures only show certain components of the apparatus and systems described herein, it is understood that various other components may be used in conjunction with the supply management system. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, the steps in the 30 method described above may not necessarily occur in the order depicted in the accompanying diagrams, and in some cases one or more of the steps depicted may occur substantially simultaneously, or additional steps may be involved. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. ,CLAIMS:We Claim:
1. A method (800) for real-time optimization of a fired heater, the method (800) comprising:
receiving (802) one or more input parameters associated with one or more operations of the fired heater;
analyzing (804) the one or more input parameters based on operating condition of the 5 fired heater;
determining (806), based on the analyzed one or more input parameters, a set of output parameters impacting performance of the fired heater; and
controlling (808) the one or more optimizing tasks, based on the set of output parameters, to improve the performance of the fired heater. 10
2. The method (800) as claimed in claim 1, wherein the one or more input parameters corresponds to fuel specification, fuel flow rate, excess air, ambient condition, and process variation.
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3. The method (800) as claimed in claim 1, wherein the operating condition of the fired heater is selected from condition of the fired heater present at current time or condition available at any historical period post designing of the fired heater.
4. The method (800) as claimed in claim 1, wherein the set of output parameters corresponds 20 to excess air, flue gas exit temperature, air preheater bypass damper settings and stack damper opening.
5. The method (800) as claimed in claim 1, wherein the one or more optimizing tasks is selected from at least one of: fired heater leakage, fired heater tuning, equipment protection and 25 identification of potential heat recovery.
6. The method (800) as claimed in claim 1, wherein controlling (808) one or more optimizing tasks of the fired heater further comprising:
identifying (808) at least one safe operating condition when the set of output parameters 30 is determined to be present within a predefined range; and
storing (808) the one or more input parameters and corresponding set of output parameters during the safe operating condition.
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7. The method (800) as claimed in claim 1, wherein controlling (808) one or more optimizing tasks of the fired heater further comprising:
identifying (808) at least one unsafe operating condition when the set of output parameters is determined to be present outside a predefined range; and 5
generating (808) an alert or action summary for an operator of the fired heater to take necessary measures for controlling the one or more optimizing tasks.
8. An apparatus (200) for real-time optimization of a fired heater, the apparatus (200) comprising: 10
one or more sensors (202) configured to sense and provide one or more input parameters associated with one or more operations of the fired heater;
a processing unit (204) coupled to the one or more sensors (202), wherein the processing unit is (204) configured to:
receive the one or more input parameters associated with the one or more 15 operations of the fired heater;
analyze the one or more input parameters based on operating condition of the fired heater;
determine, based on the analyzed one or more input parameters, a set of output parameters impacting the performance of the fired heater; and 20
control the one or more optimizing tasks, based on the set of output parameters, to improve the performance of the fired heater.
9. The apparatus (200) as claimed in claim 8, wherein the one or more input parameters corresponds to fuel specification, fuel flow rate, excess air, ambient condition, and process 25 variation.
10. The apparatus (200) as claimed in claim 8, wherein the processing unit (204) is configured to select the operating condition of the fired heater from either the condition of the fired heater present at current time or the condition available at any historical period post designing of the 30 fired heater.
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11. The apparatus (200) as claimed in claim 8, wherein the set of output parameters corresponds to excess air, flue gas exit temperature, air preheater bypass damper settings and stack damper opening.
12. The apparatus (200) as claimed in claim 8, wherein the processing unit (204) is configured 5 to select the one or more optimizing tasks from at least one of: fired heater leakage, fired heater tuning, equipment protection and identification of potential heat recovery.
13. The apparatus (200) as claimed in claim 8, wherein to control the one or more optimizing tasks of the fired heater, the processing unit (204) is further configured to: 10
identify at least one safe operating condition when the set of output parameters are determined to be present within a predefined range; and
store the one or more input parameters and corresponding set of output parameters during the safe operating condition.
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14. The apparatus (200) as claimed in claim 8, wherein to control the one or more optimizing tasks of the fired heater, the processing unit (204) is further configured to:
identify at least one unsafe operating condition when the set of output parameters is determined to be present outside a predefined range; and
generate an alert or action summary for an operator of the fired heater to take necessary 20 measures for controlling the one or more optimizing tasks.