CN110770581A - Method and system for analyzing fuel gas - Google Patents
Method and system for analyzing fuel gas Download PDFInfo
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- CN110770581A CN110770581A CN201780092400.1A CN201780092400A CN110770581A CN 110770581 A CN110770581 A CN 110770581A CN 201780092400 A CN201780092400 A CN 201780092400A CN 110770581 A CN110770581 A CN 110770581A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/22—Fuels, explosives
- G01N33/225—Gaseous fuels, e.g. natural gas
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N31/00—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods
- G01N31/12—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods using combustion
Abstract
The invention relates to a method and a system (100) for analyzing a fuel gas, wherein a predetermined amount of fuel gas (110) is reacted with an oxygen containing gas (120) to produce an analysis gas (130), wherein an oxygen content of the analysis gas is determined (140), and wherein a property of the fuel gas is evaluated (160) depending on the determined oxygen content of the analysis gas.
Description
The present invention relates to a method and system for analyzing a gas.
Prior Art
For certain chemical processes of gases, particularly hydrocarbon gases or hydrocarbon-containing gases, it may be important to know the specific characteristics of the gas in order to optimally perform these processes, particularly if these characteristics change over time. For example, for combustion of a gas or fuel gas, it may be desirable to know the air-to-fuel ratio of the gas, which describes the ratio of air to fuel gas for optimal combustion. This is particularly true for natural gas, as the composition of natural gas often changes over time.
For other chemical processes, it may be desirable to know the specific composition of the gas, for example, in order to control the corresponding process. However, methods for measuring gas composition, such as fourier transform infrared spectroscopy (FTIR), mass spectrometry, gas chromatography, or gas chromatography-mass spectrometry (GC-MS), are expensive, complex, and elaborate. In some cases, other methods, such as infrared gas analyzers, do not produce reliable or repeatable results.
It is therefore an object of the present invention to provide a method for evaluating a property of a gas, in particular the composition or the air-fuel ratio of the gas, in particular of a hydrocarbon gas or a hydrocarbon-containing gas, or more generally of a gas that reacts with oxygen.
Disclosure of Invention
The present invention relates to a method and a system for analyzing a gas having the features of the independent claims. The advantages and embodiments of the method and the system according to the invention arise in a similar manner from the following description. Other advantages and embodiments of the invention will become apparent from the description and drawings.
In this context, the word "gas" is to be understood as meaning a single gas as well as mixtures of different single gases. Gas especially refers to a hydrocarbon gas or comprises one or more hydrocarbons. In particular, the gas may be natural gas. More generally, the gas consists of or comprises a component capable of reacting or interacting with oxygen.
A predetermined amount or quantity of gas (also called process gas) is mixed with an oxygen-containing gas to produce an analyte gas. For example, oxygen, air and/or laughing gas may be used as the oxygen-containing gas. The analysis gas refers in particular to the product of a chemical reaction of a process gas and an oxygen-containing gas.
To this end, the corresponding analysis system comprises a mixing unit adapted to mix a predetermined amount of gas with an oxygen-containing gas and to generate an analysis gas. For example, the mixing unit may comprise a first conduit through which the gas is guided, the first conduit merging with a second conduit through which the oxygen comprising gas is guided.
The oxygen content of the analysis gas is determined. In particular, the absolute oxygen content or the oxygen concentration in the analysis gas is determined. For this purpose, an oxygen determination unit, for example a lambda sensor and/or a paramagnetic sensor and/or an amperometric sensor, is provided. In particular, the analysis gas is guided through an oxygen determination unit and the oxygen content of the corresponding analysis gas flow is determined.
The oxygen determination unit is in particular heated, in particular a lambda sensor providing heating. Thus, by heating the oxygen determination unit, the analysis gas guided through the oxygen determination unit is also heated, so that a chemical reaction can be triggered in particular.
The characteristics of the gas are evaluated based on the determined oxygen content of the analyzed gas. For this purpose, an evaluation unit is provided and connected to the analysis system. The invention thus provides new possibilities for easy evaluation of the properties of the gas. Depending on the specific composition of the gas, a specific chemical reaction of the gas and the oxygen-containing gas will take place, and the analysis gas will therefore have a specific oxygen content. Thus, analyzing the oxygen content of the gas creates the possibility to draw conclusions about the properties of the gas, such as the composition.
In particular, the basic properties or properties of the gas may be known in advance. By means of the analysis method according to the invention, the gas can be analyzed in particular for further properties based on the basic property profile. One essential attribute of natural gas, for example, is that it contains specific hydrocarbons, hydrogen and nitrogen as the main components. Knowing how these components react with the oxygen-containing gas confirms or confirms the presence of the components in the pseudo-gas. As a property, it is possible, for example, to assess whether the gas does indeed contain the component, in particular in its specific concentration. Knowledge about the specific reaction of the gas components with the oxygen-containing gas or the relationship between the content of a specific component in the gas and the oxygen content of the analysis gas can be provided in particular in the form of a look-up table.
It should be understood that the analysis system may include other elements, such as pumps, throttle valves, and the like. For example, a pump may be provided in particular to convey the analyte gas through the oxygen determination unit. The pump may in particular be arranged downstream of the oxygen determination unit. It is also possible not to pump gas but to suck gas in, for example in case the gas contains components that may damage the pump. The analysis system may in particular be calibrated, for example by means of a known test gas having a known composition.
A predetermined or test amount of gas may be extracted, inter alia, from a unit containing the gas. In particular, a predetermined amount may be permanently extracted from the unit and mixed with an oxygen-containing gas in order to analyze the gas over time. Thus, a constant gas flow may in particular be mixed with the oxygen-containing gas, and a constant analysis gas flow may be conveyed through the oxygen determination unit. Thus, a change in the characteristic of the gas can be detected.
Advantageously, the amount of oxygen-containing gas mixed with the predetermined amount of gas is controlled in dependence on the determined oxygen content of the analysis gas. The amount of oxygen-containing gas is preferably controlled such that the determined oxygen content of the analysis gas remains constant. A particular value of the oxygen content of the analysis gas may conveniently be used as the corresponding set point. The amount of oxygen-containing gas that needs to be mixed with the gas in order to keep the oxygen content of the analysis gas constant particularly enables conclusions to be drawn about the properties of the gas. Therefore, the characteristics of the gas are preferably evaluated in accordance with this controlled amount of the oxygen-containing gas.
For example, if the gas contains components that react with oxygen, these components will react with the oxygen-containing gas and therefore the oxygen content of the analyte gas will be relatively low. Therefore, in order to keep the oxygen content of the analysis gas constant, a relatively large amount of oxygen-containing gas must be mixed with the gas. For example, if the composition of the gas changes, the oxygen content of the analyte gas also changes. Therefore, it is also necessary to change the specific amount of oxygen-containing gas mixed with the test amount of gas so that the oxygen content of the analysis gas is kept constant. This variation in the amount of oxygen-containing gas enables conclusions to be drawn about the variation in the properties of the gas, in particular its composition.
Alternatively, it is advantageous to mix a constant amount of oxygen-containing gas with a predetermined amount of gas. Therefore, the oxygen content of the analysis gas does not remain constant and may vary depending on the composition of the gas. The properties of the gas are therefore advantageously evaluated on the basis of the determined oxygen content of the analysis gas with a constant amount of oxygen-containing gas.
According to a preferred embodiment, the temperature of the predetermined amount of gas and/or the temperature of the oxygen containing gas and/or the temperature of the analysis gas is determined and/or adjusted. Preferably, a predetermined amount of gas and/or oxygen-containing gas and/or analyte gas is heated. Thus, in particular, a chemical reaction of the gas and the oxygen-containing gas can be triggered. In addition, thermochemically stable components of the gas may also be caused to react with the oxygen-containing gas. For this purpose, the first and/or second and/or third duct may preferably be at least partially heated; wherein a predetermined amount of gas is directed through a first conduit, an oxygen-containing gas is directed through a second conduit, and an analyte gas is directed through a third conduit. Advantageously, the first duct and/or the second duct and/or the third duct are provided at least partially inside the heating furnace. Alternatively or additionally, the oxygen determination unit is advantageously heated. The analysis gas guided through the oxygen determination unit is therefore preferably likewise heated.
Preferably, additional analytical values of the analytical gas can be determined, and advantageously the absolute composition of the gas or the absolute content of the gas components can be determined from said values. The analysis may also be combined, for example, with conventional methods of assessing gas composition for verification purposes or to more accurately assess gas properties.
It is advantageous to determine the flow rate of the analysis gas, in particular downstream of the oxygen determination unit. To this end, the analysis system advantageously comprises a corresponding flow meter. The composition, in particular the absolute content of the gas components of the gas is preferably evaluated on the basis of the determined flow rate and the determined oxygen content of the analysis gas.
According to an advantageous embodiment, the dew point of the analysis gas is determined, in particular downstream of the oxygen determination unit. A corresponding dew point analysis unit is provided in particular for this purpose, in particular downstream of the flow meter. Preferably, the hydrogen content, in particular the absolute hydrogen content, of the gas is evaluated from the determined dew point and the determined oxygen content of the analysis gas. The hydrogen in the gas reacts in particular in a specific manner with the oxygen-containing gas, so that the dew point of the analysis gas is specifically influenced. Thus, analyzing the dew point of the gas enables conclusions to be drawn, inter alia, about the hydrogen content of the gas.
Preferably, the carbon dioxide content of the analysis gas is determined, in particular downstream of the oxygen determination unit. The analysis system therefore preferably comprises a corresponding capnograph, in particular downstream of the dew point determining unit. Advantageously, the carbon content, in particular the absolute carbon content, of the gas is evaluated from the determined carbon dioxide content and the determined oxygen content of the analysis gas. The carbon in the gas reacts in particular in a specific manner with the oxygen-containing gas, so that the carbon dioxide content of the analysis gas is specifically influenced. Thus, analyzing the carbon dioxide content of a gas particularly enables conclusions to be drawn about the carbon content of the gas. In part, a cold trap may be provided upstream of the capnograph to condense the vapors of the analysis gas stream. The determined dew point and/or carbon dioxide content may also be used, inter alia, to more accurately determine the analysis gas flow rate.
According to a preferred embodiment, the predetermined amount of gas has a constant pressure and/or the oxygen containing gas also has a constant pressure. The gas and the oxygen-containing gas may have the same pressure (e.g. 20 mbar) or have different pressures. Furthermore, the temperature of the predetermined amount of gas and/or oxygen-containing gas is preferably also constant. Preferably, a first throttle valve may be provided for the vapour of the gas and/or a second throttle valve may be provided for the oxygen-containing gas. By means of these throttle valves, the flow of gas and/or oxygen-containing gas can be controlled, among other things. Advantageously, the partial pressure of oxygen in the analysis gas is determined. The characteristics of the gas, in particular the air-fuel ratio, are preferably evaluated on the basis of said constant pressures and flows of gas and oxygen-containing gas and on the basis of the determined oxygen partial pressure.
Advantageously, the gas is generated within the process unit. Preferably, a predetermined amount of gas is mixed with the oxygen-containing gas to produce the analyte gas in a process unit mixing means in the process unit. The analyte gas is advantageously extracted from the process unit mixing means. Thus, the temperature within the process unit is particularly useful for triggering a chemical reaction of the gas and the oxygen-containing gas.
As the process unit mixing means, an analysis gas extraction line and an oxygen injection line may preferably be provided. The first portion of the analysis gas extraction line is preferably located inside the process unit, while the second portion of the analysis gas extraction line is located outside the process unit. A predetermined amount of gas to be mixed with the oxygen-containing gas may be collected inside the first portion of the analysis gas extraction conduit. It may be advantageous to provide the oxygen injection duct at least partially inside the first portion of the analysis gas extraction duct. An oxygen-containing gas is thus injected into the first portion of the analysis gas extraction duct by means of the oxygen injection duct, so that a predetermined amount of gas is mixed with the oxygen-containing gas inside the first portion of the analysis gas extraction duct. The analysis gas is then extracted from the process unit by means of an analysis gas extraction line.
According to a particularly preferred embodiment, the air-fuel ratio for the combustion of the gas is evaluated as a property of the gas on the basis of the determined oxygen content of the analysis gas. The mass ratio of air, oxygen or oxygen-containing gas to gas can be determined in particular as the air-fuel ratio. In particular, an optimal air-fuel ratio for optimal combustion of the gas may be evaluated. By means of the air-fuel ratio, the amount of air, oxygen or oxygen-containing gas used for the combustion of the gas can be determined, among other things. Conveniently, the air-fuel equivalence ratio λ may be determined by means of an air-fuel ratio. Thus, the present invention enables optimal combustion of gases even if the specific composition of the gases is not known in detail.
According to a particularly advantageous embodiment of the invention, the gas is a fuel gas, preferably natural gas. Preferably, the combustion of the fuel gas is carried out as a function of the evaluated properties of the fuel gas, in particular as a function of the evaluated air-fuel ratio. Therefore, the present invention enables optimum combustion of the fuel gas even if the specific composition of the fuel gas is not known in detail.
Furthermore, an optimal combustion of fuel gases with varying composition can be achieved. For varying fuel gas compositions, the necessary amount of air, oxygen or oxygen-containing gas for efficient combustion of the fuel gas also varies. By means of gas analysis, this amount of air, oxygen or oxygen-containing gas can be easily determined and clean, complete and efficient combustion of the fuel gas can be achieved. A corresponding specific or test quantity of a specific fuel gas can be conveniently and permanently extracted from, for example, a unit containing the fuel gas, and a corresponding characteristic can be permanently determined in order to react to possible fluctuations in the composition of the fuel gas.
The composition of natural gas has been considered quite stable. However, recent studies have shown that there can be significant fluctuations in natural gas composition. By means of gas analysis, an efficient combustion of natural gas can be achieved, in particular by evaluating the air-fuel ratio of a specific natural gas and performing the combustion of this natural gas according to the evaluated air-fuel ratio. Alternatively or in addition, the specific composition, preferably the absolute composition, in particular the content of carbon, hydrogen, oxygen and/or nitrogen, of the natural gas may be evaluated.
According to a particularly preferred embodiment, the composition for the gas is evaluated as a property of the gas, depending on the determined oxygen content of the analysis gas. Thus, as a property of the gas, it can be evaluated in particular whether the gas comprises a specific component, in particular a specific molecule or element, in particular a specific hydrocarbon. Alternatively or in addition, the relative composition may be determined in particular as a property, in particular the ratio of the specific components of the gas. Alternatively or in addition, the absolute composition of the gas, i.e. the specific content of a specific component of the gas, in particular the specific content of a specific molecule or element, may be evaluated in particular.
The invention thus enables an easy, economical and reproducible assessment of the gas composition at low cost, which is in particular less elaborate and more cost-effective than conventional methods, such as fourier transform infrared spectroscopy (FTIR), mass spectrometry, gas chromatography or gas chromatography-mass spectrometry (GC-MS), and in particular more reproducible than conventional methods, such as infrared analyzers.
According to a particularly advantageous embodiment of the invention, the gas is a process gas, which is produced during a chemical process, preferably during a thermochemical process of a hydrocarbon-containing gas. Preferably, the process gas is generated during pyrolysis, preferably of hydrocarbons. It is advantageous to control the chemical process in dependence on the evaluated property of the gas, in particular in dependence on the evaluated composition of the gas. The metering control of chemical processes, particularly thermochemical processes, is often elaborate and expensive. The invention enables easy, economical and efficient process control with low costs.
Advantageously, a predetermined amount of process gas is extracted from a process unit in which a chemical process, in particular a thermochemical process, is carried out. For example, a predetermined amount of process gas may be extracted from the process unit by means of the first conduit of the analysis system. Preferably, a specific amount of process gas can be permanently extracted from the process unit, thus enabling a continuous evaluation of the process gas properties. Thus, a predetermined amount of process gas is conducted out of the process unit, and the analysis of the process gas is conveniently performed outside the process unit. The atmosphere and the chemical process inside the process unit are thus particularly unaffected by the gas analysis. Furthermore, the analysis of the gas may be performed independently of the process unit load, e.g. independently of the material, size, homogeneity of the mechanical parts processed in the process unit. Furthermore, the analytical system can also be easily implemented without or with minimal configuration changes of the process unit.
The gas analysis according to the present invention can be used to analyze gases produced in a variety of different chemical processes, particularly thermochemical processes, and preferably to control the corresponding processes according to the assessed properties of the gases. Some examples of chemical processes are given below, for which gas analysis may be advantageously used.
The endothermic gas or endothermic atmosphere is a gas mixture of hydrogen, carbon monoxide, carbon dioxide and/or nitrogen and can be used, for example, as a protective gas in the thermal treatment of metals. An endothermic atmosphere may be prepared by combusting a hydrocarbon gas with a limited supply of air (i.e., at high oxygen deficit). In particular, natural gas and/or propane are used as hydrocarbon gases for the preparation of endothermic atmospheres. For efficient endothermic atmosphere preparation, it is important to know the specific composition of the corresponding hydrocarbon gas. By means of gas analysis, the composition can be evaluated and the endothermic atmosphere preparation can be controlled according to the evaluated composition. Thus, an endothermic atmosphere can be efficiently produced, for example also from natural gas with a varying composition.
The chemical process may, for example, be a multi-stage process, wherein a process gas having a particular composition is generated during a particular stage of the multi-stage process. If it is determined during the evaluation of the process gas characteristics that the particular composition is no longer present, it can be detected that the particular stage has been completed and a subsequent stage of the process can be initiated.
For example, the debinding process is a process stage of the sintering process during which the process gas contains hydrocarbons. In this case, it can be evaluated, for example, whether these hydrocarbons used in the de-binding process are part of the process gas composition. If it is determined that the corresponding hydrocarbon is no longer present, it may be detected that the debinding process has been completed and a subsequent sintering process stage may be initiated. For example, the sintering process may be performed during a Metal Injection Molding (MIM) or during a cemented carbide sintering process.
During the preparation of the carbon fibers, a pyrolysis of the corresponding fiber material is performed. By means of gas analysis, the presence of hydrocarbons, such as tar, produced during the pyrolysis can be evaluated in order to control the carbon fiber production. The process time for carbon fiber production and the necessary amount of purge gas may be particularly reduced.
Carbonization is a heat treatment process used to increase the hardness of low carbon steel or iron. Upon heating in the presence of carbonaceous material, the corresponding metal absorbs the carbon. The low-pressure carbonization is carried out in a vacuum furnace, alternatively in which a hydrocarbon-containing gas (for example methane CH) is injected4Acetylene C2H2And/or propane C3H8) And neutral gases for diffusion (e.g. N)2). Subsequently, quenching of the metal part is performed. A mixture of hydrogen and helium may be used as the corresponding quench gas. By means of gas analysis, examples can be evaluatedSuch as the hydrocarbon content of the atmosphere inside the vacuum furnace or the gaseous atmosphere discharged from the vacuum furnace. With the aid of these hydrocarbon contents, conclusions can be drawn in particular about the carbon uptake of the metal parts. The ratio of hydrogen and helium in the quench gas can also be monitored by means of gas analysis.
The heat treatment or annealing of the metallic component in coil form may be performed in a bell furnace with a hydrocarbon atmosphere. The cleanliness of the coil during annealing depends inter alia on the evaporation behavior of the rolling oil or rolling emulsion. By means of gas analysis, the atmosphere inside the bell furnace can be evaluated, in particular in order to evaluate the evaporation behavior of the rolling oil or rolling emulsion. For example, the content of methane, carbon dioxide and/or carbon monoxide in the furnace atmosphere may be evaluated.
The so-called WASTOX process is a combustion process which can be used, for example, for the recovery of carbonaceous metal waste. If unburned hydrocarbons and/or carbon monoxide are detected in the exhaust gases of the furnace, the combustion process is controlled accordingly so that these gases are combusted within the furnace itself. Therefore, organic pollutants in the metal released during combustion are used as fuel. With the aid of gas analysis, the composition of the exhaust gas can be evaluated and the presence of hydrocarbons and/or carbon monoxide can be detected.
It should be noted that the above-mentioned features as well as the features to be further described below can be used not only in the respectively indicated combination but also further combined or used individually without departing from the scope of the invention.
The invention will now be further described, by way of example, with reference to the accompanying drawings, in which:
fig. 1a, 1b, 1c each schematically show a preferred embodiment of an analysis system for analyzing a gas according to the invention, which analysis system is adapted to perform a preferred embodiment of a method for analyzing a gas according to the invention,
fig. 2 schematically shows a preferred embodiment of an analysis system for analyzing a gas according to the invention, which analysis system is adapted to perform a preferred embodiment of a method for analyzing a gas according to the invention, and
fig. 3a, 3b each schematically show a preferred embodiment of an analysis system for analyzing a gas according to the present invention, which analysis system is adapted to perform a preferred embodiment of a method for analyzing a gas according to the present invention.
Detailed Description
In the drawings, the same reference numerals refer to the same or equivalent elements.
In fig. 1a, a preferred embodiment of an analysis system 100 for analyzing a gas according to the present invention is schematically shown. The analysis system 100 is adapted to perform a preferred embodiment of the method for analyzing a gas according to the present invention.
In the process of preparing the process gas, a thermochemical process is performed in the process unit 101 (e.g., a sintering process of a metal part). The process unit 101 may be, for example, a furnace. The analysis system 100 is adapted to perform an analysis of the process gas generated in the furnace and to evaluate the properties of the process gas.
For gas analysis, a predetermined amount of process gas is extracted from the heating furnace 101. To this end, a first conduit 110 is provided through which a constant flow of process gas is extracted from the furnace 101.
A pump and/or compressor 111 is provided for compressing the extracted process gas. Furthermore, a heating mechanism 112 is provided in order to heat the conduit 110 and thus the extracted process gas. For example, a small-sized heating furnace or heat exchanger may be provided as the heating mechanism 112 in which a part of the duct 110 is disposed.
The extracted process gas is mixed with an oxygen-containing gas (e.g., oxygen). For this purpose, an oxygen supply 102 and a second conduit 120 are provided through which the oxygen flow is conveyed. The flow control unit 121 is provided to control the flow of oxygen.
The first pipe 110 and the second pipe 120 are merged into a third pipe 130. Thus, the heated extracted process gas stream is mixed with the oxygen stream. The heated process gas chemically reacts with oxygen to produce an analyte gas, which is transported through a third conduit 130.
The first, second and third conduits 110, 120, 130 as well as the compressor 111, the heating means 112 and the flow control unit 121 are in particular part of a mixing unit 103 which is adapted to mix a predetermined amount of extracted process gas with oxygen and to generate an analysis gas flow.
In the third conduit 130, an oxygen determination unit 140, for example a lambda sensor, is provided. The oxygen content of the analysis gas is determined by means of the oxygen determination unit 140. The determined oxygen content value is transmitted from the lambda sensor 140 to a control unit or evaluation unit 160, which is indicated by reference numeral 140 a. For this transmission 140a, a wireless communication link may be established between the lambda sensor 140 and the control unit 160, for example.
A flow meter 151 is provided downstream of the oxygen determination unit 140 in order to determine the flow rate of the analysis gas flow. The flow meter 151 also transmits the determined flow value to the control unit 160, e.g. by means of a wireless connection, which is indicated by reference numeral 151 a.
The control unit 160 evaluates the properties of the process gas on the basis of the determined oxygen content of the analysis gas flow and in particular on the basis of the determined flow rate of the analysis gas flow. In particular, the control unit 160 evaluates the composition of the gas based on the determined oxygen content and the determined flow rate of the analysis gas flow. In particular, it is possible to evaluate whether the process gas contains hydrocarbons. By means of this flow, the absolute hydrocarbon content of the process gas can be estimated.
Furthermore, the control unit 160 is adapted to control the amount of oxygen mixed with the process gas in dependence of the determined oxygen content of the analysis gas. For this reason, the control unit 160 controls the flow control unit 121, which is indicated by reference numeral 121 a. Thus, the flow of oxygen in the second conduit 120 is controlled such that the oxygen content of the analysis gas flow in the third conduit 130 is kept constant.
Furthermore, the thermochemical process in the furnace 101 is controlled according to the evaluated characteristics of the gas, in particular according to the evaluated composition of the gas.
During the sintering process inside the heating furnace 101, debonding of the metal parts occurs. During this debinding process, a specific hydrocarbon-containing process gas is generated in the heating furnace 101. The hydrocarbon-containing process gas reacts specifically with oxygen, thus producing a specific analysis gas with a specific oxygen content. When the specific oxygen content is determined by means of the lambda sensor 140, the control unit 160 detects that the debonding process has started. The relationship between the content of the hydrocarbon in the process gas and the content of oxygen in the analysis gas may be provided, for example, in the form of a look-up table stored in the control unit 160.
When it is determined that the specific oxygen content is no longer present, the control unit 160 detects that the debonding process has been completed. In this case, the control unit 160 may send a corresponding command to the heating furnace 101 in order to start a subsequent stage of the sintering process, which is indicated by reference numeral 101 a.
In fig. 1b, another preferred embodiment of an analysis system 100' according to the present invention is schematically shown, similar to the system 100 of fig. 1 a.
In contrast to the system 100 of fig. 1a, the flow of oxygen in the second conduit 120 is not controlled in the system 100' shown in fig. 1 b. Thus, the mixing unit 103' does not comprise a flow control unit. Instead, a throttle valve 122 is provided in the second conduit 120 to provide a constant flow and constant pressure flow of oxygen. Thus, the oxygen content of the analysis gas stream in the third conduit 130 does not remain constant, but may vary depending on the composition of the process gas.
Fig. 1c schematically shows another preferred embodiment of an analysis system 100 "according to the present invention, similar to the system 100' of fig. 1 b.
According to this embodiment, no heating means and no compressor are provided in the first conduit 110 of the corresponding mixing unit 103 ". Instead, a heating mechanism 132 is provided in the third conduit 130 to heat the mixture of process gas and oxygen. For example, a small-sized heating furnace or heat exchanger may be provided as the heating mechanism 132.
Analogously to the systems 100 and 100' of fig. 1a and 1b, the oxygen content of the analysis gas flow in the third line 130 is determined by means of the lambda sensor 140 and the flow rate is determined by means of the flow meter 151.
Downstream of the flow meter 151, a compressor 152, a dew point analysis unit 153, a cold trap 154 and a capnograph 155 are provided. By means of the dew point analysis unit 153, the dew point of the analysis gas is determined and transmitted to the control unit 160, which is indicated by reference numeral 153 a. The vapors of the analysis gas stream are condensed by means of the cold trap 154 and the carbon dioxide content of the analysis gas stream is determined by means of the carbon dioxide analyzer 155 and transmitted to the control unit 160 as indicated by reference 155 a.
Based on the determined dew point and the determined oxygen content of the analysis gas, the control unit 160 evaluates the hydrogen content of the process gas. Furthermore, the control unit 160 evaluates the carbon content of the process gas based on the determined carbon dioxide content and the determined oxygen content of the analysis gas.
According to a preferred embodiment of the invention, the process gas may also be mixed with an oxygen-containing gas inside the process unit in which the process gas is generated. Fig. 2 schematically shows a part of a corresponding preferred analysis system according to the present invention.
Fig. 2 shows a portion of a process unit 201, such as a furnace. A thermochemical process, such as a sintering process, is performed in the interior 201a of the heating furnace 201, similar to the heating furnace 101 shown in fig. 1a to 1 c. A process gas 211 is generated in the interior 201a of the heating furnace 201. The walls of the furnace are referred to as 201c and the exterior of the furnace is referred to as 201 b.
Process cell mixing means are provided inside the furnace 201 in order to generate an analysis gas inside the process cell mixing means and thus inside the furnace 201. The process unit mixing means includes an analysis gas extraction line 210 and an oxygen injection line 220.
The analysis gas extraction duct 210 is provided such that a first portion 210a of the duct 210 is disposed in the interior 201a of the heating furnace 201 and a second portion 210b of the duct 210 is disposed in the exterior 201b of the heating furnace 201. A predetermined amount of process gas accumulates in particular in the first portion 210a of the analysis gas extraction duct 210.
The oxygen injection pipe 220 is at least partially arranged inside the analysis gas extraction pipe 210. Specifically, the end 220a of the oxygen injection duct 220 is arranged in the first section 210a of the analysis gas extraction duct 210, and thus in the interior 201a of the heating furnace 201. Further, at a portion of the oxygen injection pipe 220 disposed in the first portion 210a of the analysis gas extraction pipe 210, a hole 220b is provided.
An oxygen-containing gas 221 (e.g. oxygen) is injected into the first portion 210a of the analysis gas extraction duct 210 through the holes 220b by means of the oxygen injection duct 220. Thus, the process gas 211 accumulated in the first portion 210a of the analysis gas extraction pipe 210 is mixed with the injected oxygen gas 221. The temperature within the furnace triggers the chemical reaction of the process gas 211 and the oxygen 221. Accordingly, a corresponding analysis gas 231 is generated in the interior 201a of the heating furnace 201. The analysis gas 231 is extracted from the heating furnace 201 by means of the analysis gas extraction duct 210 and transported to the oxygen determination unit, as described above.
Fig. 3a schematically shows another preferred embodiment of an analysis system 300 according to the present invention, which is adapted to perform a preferred embodiment of the method according to the present invention.
Inside the process unit 301 (e.g., a furnace), combustion of fuel gas (e.g., natural gas) and air is performed. For this purpose, a natural gas supply device 301b and an air supply device 301c are provided. The amount of air required for effective combustion of natural gas depends on the specific composition of the natural gas. To achieve optimal combustion, the natural gas is analyzed.
For this purpose, a predetermined amount of natural gas is extracted from the natural gas supply device 301b by means of the first pipeline 310. Similar to the gas analysis systems 101, 101' and 101 "shown in fig. 1a to 1c, an oxygen supply 302 and a second conduit 320 are provided through which the oxygen flow is guided. The first and second conduits 310 and 320 merge into a third conduit 330. Thus, the extracted natural gas stream is mixed with the oxygen stream. The natural gas reacts with the oxygen and produces an analyte gas, which is transported through a third pipeline 330.
An oxygen determination unit 340, for example a lambda sensor, is provided which determines the oxygen content of the analysis gas flow. A flow meter 351 is provided to determine the flow rate of the analyte gas stream. The determined values of oxygen content and flow are transmitted from the lambda sensor 340 and the flow meter 351 to a control unit or evaluation unit 360, which is indicated by reference numerals 340a and 351 a.
The control unit 360 evaluates the properties of the process gas on the basis of the determined oxygen content of the analysis gas flow and in particular on the basis of the determined flow rate of the analysis gas flow. Specifically, the control unit 360 evaluates the air-fuel ratio of the natural gas for optimal combustion. According to this determined optimum air-fuel ratio, the control unit 360 controls the valve 304 in the natural gas supply device 301b, which is indicated by reference numeral 301 a. Accordingly, the control unit 360 controls the amount of natural gas supplied to the heating furnace 301 so that the mixture of natural gas and air according to the determined optimum air-fuel ratio is supplied to the heating furnace 301. With the aid of the gas analysis system 300, the optimum air-fuel ratio is permanently determined in order to react to possible fluctuations in the composition of the natural gas.
Furthermore, the control unit 360 is adapted to control the amount of oxygen mixed with the natural gas in dependence of the determined oxygen content of the analysis gas. For this purpose, the control unit 360 controls the flow control unit 321 in the second pipe 320, which is indicated by reference numeral 321 a. The first conduit 310, the second conduit 320, the third conduit 330 and the flow control unit 321 are in particular part of the corresponding mixing unit 303.
Fig. 3b schematically shows another preferred embodiment of an analysis system 300' according to the present invention, similar to the system 300 of fig. 3 a.
In the mixing unit 303 'of the system 300', a first throttle 311 is provided in the first conduit 310 and a second throttle 322 is provided in the second conduit 320. By means of these throttle valves 311, 322, a natural gas stream with a constant pressure of, for example, 20 bar can be mixed with an oxygen stream with a constant pressure of, for example, also 20 bar.
A thermal insulation device 341 is provided for the lambda sensor 340. Furthermore, a temperature sensor 342 is provided to determine the temperature of the lambda sensor 340. The determined temperature is transmitted to the control unit 360, which is indicated by reference numeral 342 a.
Furthermore, a partial pressure unit 352 is provided to determine the partial pressure of oxygen in the analysis gas flow in the third conduit 330, which partial pressure is transmitted to a control unit 360, which is indicated by reference numeral 352 a.
The control unit 360 determines the optimum air/fuel ratio on the basis of the constant pressures and the corresponding flows of the natural gas and oxygen in the ducts 310 and 320, in addition to the determined partial pressures, on the basis of the determined oxygen content of the analysis gas and on the basis of the temperature of the lambda sensor. According to the estimated optimum air-fuel ratio, the control unit 360 controls the valve 304 in the natural gas supply device 301b so that the mixture of natural gas and air according to the determined optimum air-fuel ratio is supplied to the heating furnace 301.
REFERENCE LIST
100 gas analysis system
100' gas analysis system
100' gas analysis system
101 process unit, furnace
102 oxygen supply device
103 mixing unit
103' mixing unit
103' mixing unit
110 first pipeline
111 pump, compressor
112 heating mechanism
120 second pipe
121 flow control unit
121a transmission between control unit 160 and flow control unit 121
122 throttle valve
130 third conduit
132 heating mechanism
140 oxygen determination unit, lambda sensor
151 flow meter
151a transfer between the flow meter 151 and the control unit 160
152 compressor 152
153 dew point analysis unit
153a dew point analysis unit 153 and control unit 160
154 Cold trap
155 carbon dioxide analyzer
155a capnograph 155 and control unit 160
160 evaluation unit, control unit
201 Process Unit, heating furnace
201b outside the furnace 201
201c walls of the furnace 201
203 mixing unit
210 analysis gas extraction line
210a analysis of a first portion of the gas extraction line 210
210b analyze a second portion of the gas extraction line 210
211 process gas
220 oxygen injection pipeline
220b bore 220 of oxygen injection pipe
221 oxygen-containing gas, oxygen
231 analyzing gas
300 gas analysis system
300' gas analysis system
301 process unit, furnace
301b natural gas supply device
301c air supply device
302 oxygen supply device
303 mixing unit
304 natural gas supply device
303' mixing unit
310 first conduit
311 throttle valve
320 second conduit
321 flow control unit
321a transmission between control unit 360 and flow control unit 321
322 throttle valve
330 third pipeline
340 oxygen determination unit, lambda sensor
341 heat insulation device
342 temperature sensor
351 flow meter
352 voltage division unit
351a voltage dividing unit 352 and a control unit 160
360 control unit
Claims (13)
1. A method for analyzing a gas (211),
wherein a predetermined amount of the gas (211) is mixed with an oxygen containing gas (221) to produce an analysis gas (231),
wherein the oxygen content of the analysis gas (231) is determined, and
wherein the characteristic of the gas (211) is evaluated from the determined oxygen content of the analysis gas (231).
2. The method of claim 1, wherein the first and second light sources are selected from the group consisting of,
wherein the amount of the oxygen containing gas (221) mixed with the predetermined amount of the gas (211) is controlled depending on the determined oxygen content of the analysis gas (231) or
Wherein a constant amount of oxygen containing gas (221) is mixed with the predetermined amount of the gas (211).
3. Method according to claim 1 or 2, wherein the temperature of the predetermined amount of the gas (211) and/or the temperature of the oxygen containing gas (221) and/or the temperature of the analysis gas (231) is determined and/or adjusted.
4. The method according to any one of the preceding claims, wherein a flow rate of the analysis gas (231) is determined, and in particular wherein a composition, in particular an absolute content of a component, of the gas (211) is evaluated from the determined flow rate and the determined oxygen content of the analysis gas (231).
5. The method according to any one of the preceding claims, wherein a dew point of the analysis gas (231) is determined, and in particular wherein a hydrogen content, in particular an absolute hydrogen content, of the gas (211) is evaluated from the determined dew point and the determined oxygen content of the analysis gas (231).
6. The method according to any one of the preceding claims, wherein a carbon dioxide content of the analysis gas (231) is determined, and in particular wherein a carbon content, in particular an absolute carbon content, of the gas (211) is evaluated from the determined carbon dioxide content and the determined oxygen content of the analysis gas (231).
7. The method according to any of the preceding claims, wherein the predetermined amount of the gas (211) has a constant pressure, and/or wherein the oxygen containing gas has a constant pressure.
8. The method according to any one of the preceding claims,
wherein the gas (211) is generated within a process unit (101, 201),
wherein the predetermined amount of the gas (211) is mixed with the oxygen containing gas (221) to generate the analysis gas (231) within a process unit mixing means (210, 220) within a process unit (101, 201), and
wherein the analysis gas (231) is extracted from the process unit mixing means (210, 220).
9. The method according to any one of the preceding claims, wherein the composition of the gas (211) and/or the air-fuel ratio for the combustion of the gas (211) is evaluated as a characteristic of the gas (211) depending on the determined oxygen content of the analysis gas (231).
10. A method for performing combustion of a fuel gas,
wherein the air-fuel ratio for combusting the fuel gas is evaluated as a characteristic of the gas (211) according to the method of any one of the preceding claims, and
wherein the combustion of the fuel gas is performed according to the estimated air-fuel ratio.
11. A method for performing a chemical process, comprising,
wherein a process gas (211) is produced during the chemical process, in particular during a thermochemical process,
wherein the method according to any of the preceding claims, the composition of the process gas (211) is evaluated as a characteristic of the gas (211), and
wherein the chemical process is controlled in dependence of the evaluated composition of the process gas (211).
12. Analysis system (100, 100', 100", 300, 300') for analyzing a gas adapted to perform the method according to any of the preceding claims, comprising:
a mixing unit (103, 103', 203, 303, 303') adapted to mix a predetermined amount of said gas with an oxygen-containing gas and to generate an analysis gas,
an oxygen determination unit (140, 340) adapted to determine an oxygen content of the analysis gas, an
An evaluation unit (160, 360) adapted to evaluate a property of the gas based on the determined oxygen content of the analysis gas.
13. The analytical system (100, 100', 100", 300, 300') of claim 12, further comprising:
a heating mechanism (112, 132) adapted to determine and/or adjust the temperature of the predetermined amount of the gas (211) and/or the temperature of the oxygen containing gas (221) and/or the temperature of the analysis gas (231), and/or
A flow meter (151, 351) adapted to determine a flow rate of the analysis gas (231), and/or
A dew point analysis unit (153) adapted to determine the dew point of the analysis gas (231), and/or
A carbon dioxide analyzer (155) adapted to determine the carbon dioxide content of the analysis gas (231), and/or
At least one throttle valve (122, 311, 322) adapted to provide a constant pressure for the predetermined amount of the gas (211) and/or to provide a constant pressure for the oxygen containing gas.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/EP2017/025192 WO2019007473A1 (en) | 2017-07-03 | 2017-07-03 | Method and system for analysing a fuel gas |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110770581A true CN110770581A (en) | 2020-02-07 |
Family
ID=59350864
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201780092400.1A Pending CN110770581A (en) | 2017-07-03 | 2017-07-03 | Method and system for analyzing fuel gas |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP3649468A1 (en) |
| CN (1) | CN110770581A (en) |
| WO (1) | WO2019007473A1 (en) |
Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4170455A (en) * | 1976-03-11 | 1979-10-09 | Rockwell International Corporation | Gas monitoring method and apparatus therefor |
| US4433922A (en) * | 1982-07-02 | 1984-02-28 | The Babcock & Wilcox Company | Calorimeter |
| US4632572A (en) * | 1982-10-06 | 1986-12-30 | Honeywell Inc. | Impurity compensation for colorific content analyzer |
| US4657737A (en) * | 1984-03-31 | 1987-04-14 | Pierburg Gmbh & Co Kg | Apparatus for determining the fuel-air ratio of Otto engines |
| CN1071509A (en) * | 1990-08-17 | 1993-04-28 | 卡塔鲁逖克公司 | SO 2 sensor and process for detecting SO 2 |
| US5288149A (en) * | 1992-03-12 | 1994-02-22 | Panametrics, Inc. | Gas calorimeter and wobbe index meter |
| US6116207A (en) * | 2000-01-03 | 2000-09-12 | Firey; Joseph Carl | Fuel air mixer and proportioner |
| CN2886570Y (en) * | 2006-01-16 | 2007-04-04 | 张东平 | Combustion type calorimeter for measuring gas heat value |
| CN101886883A (en) * | 2010-07-05 | 2010-11-17 | 天津理工大学 | Intelligent furnace regulation decision making device for heating furnace |
| CN101910837A (en) * | 2007-10-31 | 2010-12-08 | 阿努比兹私人有限公司 | Determine the calorific value of hydrocarbon fuel and the method and the instrument that is used for this method of relative density |
| TW201213655A (en) * | 2010-08-31 | 2012-04-01 | Palmer Labs Llc | System and method for high efficiency power generation using a carbon dioxide circulating working fluid |
| NL2011821C2 (en) * | 2013-11-20 | 2015-05-26 | Hobré Instr B V | METHOD FOR ANALYZING A BIOGAS AND A DEVICE THEREOF |
| CN104713352A (en) * | 2013-12-12 | 2015-06-17 | 林德股份公司 | Method for heating a metal material in an industrial furnace |
| CN104995457A (en) * | 2013-02-21 | 2015-10-21 | 埃克森美孚上游研究公司 | Catalyst comprising oxygen storage component for treatment of gas turbine exhaust gases |
-
2017
- 2017-07-03 CN CN201780092400.1A patent/CN110770581A/en active Pending
- 2017-07-03 WO PCT/EP2017/025192 patent/WO2019007473A1/en unknown
- 2017-07-03 EP EP17739877.3A patent/EP3649468A1/en not_active Withdrawn
Patent Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4170455A (en) * | 1976-03-11 | 1979-10-09 | Rockwell International Corporation | Gas monitoring method and apparatus therefor |
| US4433922A (en) * | 1982-07-02 | 1984-02-28 | The Babcock & Wilcox Company | Calorimeter |
| US4632572A (en) * | 1982-10-06 | 1986-12-30 | Honeywell Inc. | Impurity compensation for colorific content analyzer |
| US4657737A (en) * | 1984-03-31 | 1987-04-14 | Pierburg Gmbh & Co Kg | Apparatus for determining the fuel-air ratio of Otto engines |
| CN1071509A (en) * | 1990-08-17 | 1993-04-28 | 卡塔鲁逖克公司 | SO 2 sensor and process for detecting SO 2 |
| US5288149A (en) * | 1992-03-12 | 1994-02-22 | Panametrics, Inc. | Gas calorimeter and wobbe index meter |
| US6116207A (en) * | 2000-01-03 | 2000-09-12 | Firey; Joseph Carl | Fuel air mixer and proportioner |
| CN2886570Y (en) * | 2006-01-16 | 2007-04-04 | 张东平 | Combustion type calorimeter for measuring gas heat value |
| CN101910837A (en) * | 2007-10-31 | 2010-12-08 | 阿努比兹私人有限公司 | Determine the calorific value of hydrocarbon fuel and the method and the instrument that is used for this method of relative density |
| CN101886883A (en) * | 2010-07-05 | 2010-11-17 | 天津理工大学 | Intelligent furnace regulation decision making device for heating furnace |
| TW201213655A (en) * | 2010-08-31 | 2012-04-01 | Palmer Labs Llc | System and method for high efficiency power generation using a carbon dioxide circulating working fluid |
| CN104995457A (en) * | 2013-02-21 | 2015-10-21 | 埃克森美孚上游研究公司 | Catalyst comprising oxygen storage component for treatment of gas turbine exhaust gases |
| NL2011821C2 (en) * | 2013-11-20 | 2015-05-26 | Hobré Instr B V | METHOD FOR ANALYZING A BIOGAS AND A DEVICE THEREOF |
| CN104713352A (en) * | 2013-12-12 | 2015-06-17 | 林德股份公司 | Method for heating a metal material in an industrial furnace |
Also Published As
| Publication number | Publication date |
|---|---|
| EP3649468A1 (en) | 2020-05-13 |
| WO2019007473A1 (en) | 2019-01-10 |
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