CA1180917A - Btu meter for monitoring the heating value of fuel gases - Google Patents
Btu meter for monitoring the heating value of fuel gasesInfo
- Publication number
- CA1180917A CA1180917A CA000402713A CA402713A CA1180917A CA 1180917 A CA1180917 A CA 1180917A CA 000402713 A CA000402713 A CA 000402713A CA 402713 A CA402713 A CA 402713A CA 1180917 A CA1180917 A CA 1180917A
- Authority
- CA
- Canada
- Prior art keywords
- oxygen
- fuel
- heating value
- medium
- flowing fuel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000010438 heat treatment Methods 0.000 title claims abstract description 29
- 239000002737 fuel gas Substances 0.000 title description 42
- 238000012544 monitoring process Methods 0.000 title description 3
- 239000001301 oxygen Substances 0.000 claims abstract description 44
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 44
- 239000000446 fuel Substances 0.000 claims abstract description 43
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 42
- 238000002485 combustion reaction Methods 0.000 claims description 19
- 239000000470 constituent Substances 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 12
- 230000036284 oxygen consumption Effects 0.000 claims description 5
- 238000006243 chemical reaction Methods 0.000 claims 3
- 239000000203 mixture Substances 0.000 description 19
- 239000007789 gas Substances 0.000 description 18
- 230000003197 catalytic effect Effects 0.000 description 8
- 238000005259 measurement Methods 0.000 description 7
- 239000007784 solid electrolyte Substances 0.000 description 5
- 238000007084 catalytic combustion reaction Methods 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 3
- -1 oxygen ion Chemical class 0.000 description 3
- 238000005086 pumping Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 239000003245 coal Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- BSYNRYMUTXBXSQ-UHFFFAOYSA-N Aspirin Chemical compound CC(=O)OC1=CC=CC=C1C(O)=O BSYNRYMUTXBXSQ-UHFFFAOYSA-N 0.000 description 1
- 241000950314 Figura Species 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- YWXYYJSYQOXTPL-SLPGGIOYSA-N isosorbide mononitrate Chemical compound [O-][N+](=O)O[C@@H]1CO[C@@H]2[C@@H](O)CO[C@@H]21 YWXYYJSYQOXTPL-SLPGGIOYSA-N 0.000 description 1
- 238000012886 linear function Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- 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
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Molecular Biology (AREA)
- Combustion & Propulsion (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Investigating Or Analyzing Materials Using Thermal Means (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
- Regulation And Control Of Combustion (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The oxygen consumed to deplete the fuel content of a flowing fuel medium is measured as an indication of the heating value of the fuel medium.
The oxygen consumed to deplete the fuel content of a flowing fuel medium is measured as an indication of the heating value of the fuel medium.
Description
~8C~g~7 ; 1 49,334 A ~TU M~TER FOR MONIT~RING THE
HEATING VALUE OF FUEL GASES
BACKGROUND OF THE INVENTION
The total heatin~ value of a fuel gas is the sum of the heating values of the individual combustible con-stituents. Heating value tests are regularly performed by utility gas companies to verify compliance of the fuel with Public Service Commission regulations. Calorimetric methods have been traditionally used to determine the heating value of fuel gases. The calorimetric method involves the burning of a definite volume of gas, absorb-ing the heat liberated in a known weight of water andcalculating the heat content from the temperature rise of the water. More recently, gas chromatographic analytical methods ha~e replaced the calorimetric method for deter mining heat values of fuel gases. The gas chromatograph gives a ~lantitative analysis of the constituents of the gaseous fuel. The heat value of the fuel is then calcu-lated by using the gas analytical data and the known heating values of the individual cons~ituents. ~hile the gas cnromatographic method is more rapid and more conven-ient than ~he calorimetric method, neither of the tradi-tional methods are suitable for continuous, on-line mea-surement of the heating value of the combustible con-stituents ~f a fuel gas.
Inasmuch as it is anticipated that future fuel gas supplies will be deri~ed from a variety of sourcas, i.e., coal gasiflcation, ~itn the resultant varia~ions in
HEATING VALUE OF FUEL GASES
BACKGROUND OF THE INVENTION
The total heatin~ value of a fuel gas is the sum of the heating values of the individual combustible con-stituents. Heating value tests are regularly performed by utility gas companies to verify compliance of the fuel with Public Service Commission regulations. Calorimetric methods have been traditionally used to determine the heating value of fuel gases. The calorimetric method involves the burning of a definite volume of gas, absorb-ing the heat liberated in a known weight of water andcalculating the heat content from the temperature rise of the water. More recently, gas chromatographic analytical methods ha~e replaced the calorimetric method for deter mining heat values of fuel gases. The gas chromatograph gives a ~lantitative analysis of the constituents of the gaseous fuel. The heat value of the fuel is then calcu-lated by using the gas analytical data and the known heating values of the individual cons~ituents. ~hile the gas cnromatographic method is more rapid and more conven-ient than ~he calorimetric method, neither of the tradi-tional methods are suitable for continuous, on-line mea-surement of the heating value of the combustible con-stituents ~f a fuel gas.
Inasmuch as it is anticipated that future fuel gas supplies will be deri~ed from a variety of sourcas, i.e., coal gasiflcation, ~itn the resultant varia~ions in
2 ~9,33~
heating values, there is a need for a technique whi.ch will provide a continuous measurement of the heating value of the fuel both for monitoring and process control purposes.
This technique has application in determining the ~'qual-ity" of gas supplied to industrial and residential con-sumers.
SUM~A~Y OF THE INVENTION
It has been determined experimentally that the amount of oxygen consumed by the combustion of any gaseous fuel or fuel mixture is an indication of the heating value of the fuel. There is disclosed herein an implementation of this relationship.
A sample of the fuel gas is mixed with a gas of stable or known oxygen content, i.e., air, and the mixture is supplied to a catalytic sensing electrode of a solid electrolyte oxygen ion conductive electrochemical cell. A
reference of stable oxygen concentration, i.e., air, is maintained at the reference electrode of the cell. The catalytic combustion of the fuel/air gas mixture will reduce the oxygen content and the resulting differential oxygen concentration will produce a cell EMF signal which is indicative of the oxygen consumed by the combustion of the fuel gas. ThP oxygen consumption measurement is indicative of the heating value of the fuel gas.
Alternatively the sample of the fuel gas can be supplied directly to the catalytic electrode, and with the cell operating as an oxygen pump, the oxygen transferred from the reference electrode to the catalytic electrode to react with the fuel gas will produce a cell current indic-ative of the oxygen consumed by the combustion of the fuel gas. This is a measurement of the heating value of the fuel gas.
DESCRIPTION OF TIIE DRAWI~GS
l'he invention will become more readily apparent from the following exemplary description in connection with the accompanying drawings:
8~
heating values, there is a need for a technique whi.ch will provide a continuous measurement of the heating value of the fuel both for monitoring and process control purposes.
This technique has application in determining the ~'qual-ity" of gas supplied to industrial and residential con-sumers.
SUM~A~Y OF THE INVENTION
It has been determined experimentally that the amount of oxygen consumed by the combustion of any gaseous fuel or fuel mixture is an indication of the heating value of the fuel. There is disclosed herein an implementation of this relationship.
A sample of the fuel gas is mixed with a gas of stable or known oxygen content, i.e., air, and the mixture is supplied to a catalytic sensing electrode of a solid electrolyte oxygen ion conductive electrochemical cell. A
reference of stable oxygen concentration, i.e., air, is maintained at the reference electrode of the cell. The catalytic combustion of the fuel/air gas mixture will reduce the oxygen content and the resulting differential oxygen concentration will produce a cell EMF signal which is indicative of the oxygen consumed by the combustion of the fuel gas. ThP oxygen consumption measurement is indicative of the heating value of the fuel gas.
Alternatively the sample of the fuel gas can be supplied directly to the catalytic electrode, and with the cell operating as an oxygen pump, the oxygen transferred from the reference electrode to the catalytic electrode to react with the fuel gas will produce a cell current indic-ative of the oxygen consumed by the combustion of the fuel gas. This is a measurement of the heating value of the fuel gas.
DESCRIPTION OF TIIE DRAWI~GS
l'he invention will become more readily apparent from the following exemplary description in connection with the accompanying drawings:
8~
3 4~,33~
Figure 1 is a graphical illustration of the moles of o~ygGn required for combustion of fuel gases with various heat values;
Figura 2 is a schematic illustration of an embodiment of the disclosed technioue for determining the heating value of fuel gases;
Figure 3 is a graphical illustration of the equilibrium oxygen concentration after combustion of monitored gas compositions consisting of 3 volume % fuel gas/air mixtures, i.e., a mixture of 97% air and 3% fuel gas; and Figure 4 is a schematic illustration of an alternative embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in Table I below the heat of combustion of most gaseous fuels divided by the number of moles of oxygen (2) required for complete combustion of one mole of fuel is nearly constant. It has been determined exper-imentally that the amount of oxygen consumed by the com-bustion of any gaseous fuel or fuel mixture is indicativeo the heating value of the ~uel. The oxygen consumption calculations for some typical uel gases are illustrated in Table II below. Further, a plot of this data showing the correlation between oxygen consumption and heating value is illustrated graphically in Figure 1. The heat of combustion information presented in Table I as well as the heating value information of Table III is discussed in the "Handbook of Chemistry and Physics", 3rd edition, Chemi-cal Rubber Publishing Co., 1961.
Figure 1 is a graphical illustration of the moles of o~ygGn required for combustion of fuel gases with various heat values;
Figura 2 is a schematic illustration of an embodiment of the disclosed technioue for determining the heating value of fuel gases;
Figure 3 is a graphical illustration of the equilibrium oxygen concentration after combustion of monitored gas compositions consisting of 3 volume % fuel gas/air mixtures, i.e., a mixture of 97% air and 3% fuel gas; and Figure 4 is a schematic illustration of an alternative embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in Table I below the heat of combustion of most gaseous fuels divided by the number of moles of oxygen (2) required for complete combustion of one mole of fuel is nearly constant. It has been determined exper-imentally that the amount of oxygen consumed by the com-bustion of any gaseous fuel or fuel mixture is indicativeo the heating value of the ~uel. The oxygen consumption calculations for some typical uel gases are illustrated in Table II below. Further, a plot of this data showing the correlation between oxygen consumption and heating value is illustrated graphically in Figure 1. The heat of combustion information presented in Table I as well as the heating value information of Table III is discussed in the "Handbook of Chemistry and Physics", 3rd edition, Chemi-cal Rubber Publishing Co., 1961.
4 49, 334 ' ~
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9 49,334 ~or the purposes of discussion, consider a mixture of 5% Ca4 in air at typical conditions of tempera~
ture and pressure One liter of this mixture contains 0.05 24.4 liter/mole = 0.00205 mole of CH4. Complete combustion of this methane (C~4) reauires 2 x 0.00205 =
0.0041 mole 2' or 0.0041 mole x 24.4 liter/mole = 0.1000 liter oî 2 at room temperature and pressure. Thus, the 2 content of the original one liter o gas mixture would be reduced from 20% to 10%. Since, as illustrated above, the oxygen consumption during combustion is directly related to the heat content of a fuel, the measurement of the oxygen consumed, or that remaining, provides an indi-cation of the heat content of the fuel.
An implementation of this novel techni~ue for monitoring the heating value of fuel gases on khe basis of oxygen consumed during combustion is typicall~ illustrated in Figure 2. A sample of fuel gas from-a fuel gas supply - line 10 is supplied to a fuel gas/air mixing apparatus 20 which mixes the sample of the fuel gas with a predeter~
mined amount of a gas of stable oxygen content, i.e., air, to produce a fuel gas/air mixture which is supplied to a commercially available oxygen/measuring detector 30. The fuel gas/air mixture developed by the mixing apparatus ~0 is of a constant concentration with the concentration being adjustable in terms of the air introduced into _he mixing apparatus 20. While the fuel gas/air concert-ation mixture can be adjusted to optimize the sensitivity of the system for a particular heating value region, a 3 volume %
fuel gas/air mixture (97% air, 3% fuel gas) has been selected for the pur~ose o~ discussion. Tne air content, i.e., 97%, is typically chosen to assure sufficient oxygan to completely combust the fuel at the detector 30 and rasult in a residual oxygen in the mixture after combus-tion.
49'334 The oxygen detector 30 is illustrated as con-sisting of an electrochemical cell 32 having an oxygen ion conductive solid electrolyte element 33 with a catalytic sensing electrode 34 and an oxygen reference electrode 35 disposed on opposite surfaces thereof.
A furnace mPmber 36 maintains the electrochem-ical cell 32 at an operating temperature of between 800 and 1000C to optimize the oxygen ion conductivity of the solid electrolyte 33 and to assure a catalytic combustion reaction between the oxygen and fuel constituents of the gas mixture at the catalytic sensing electrode 34. The electrodes 34 and 35 are typically platinum electrodes with the platinum electrode 34 supporting catalytic com-bustion of the oxygen and fuel constituents of the gas mixture developed by the mixing apparatus 20. The result-ing decrease in the oxygen concentration of the gas mix-ture following the catalytic combustion reaction produces a change in oxygen partial pressure across the electro-chemical cell 32 and the resulting cell EMF is measured electrically by a BTU meter 40 which is connected to the electrodes 34 and 35 via electrical leads 42 and 43. The electrical signal measured by the BTU meter 40 is mani-fested as a measurement of the heating value of the fuel gas flowing in the fuel gas supply line 10.
The operation of the solid electrolyte electro-chemical cell 32 in both a pumping mode and in a potentio-metric mode is describe~ in detail in U.S. Patent No. Re.
28,792, which is assigned to the assignee of the present invention. The use of a solid electrolyte electrochemical cell of the type described in U.S. Patent No. Re. 28,792 is illustrated in detail in U.S. Patent ~os. 3,791,936;
4,134,818 and 4,190,499, all of which are assigned to the assignee of the present invention.
The amount of oxygen consumed, or that remain-ing, following the complete fuel combustion of 3 vo~ume %
~l~8(~9~
11 49,334 fuel gas/air mixtures, such as that produced by the gas mixing apparatus 20 of Figure 2, for the fuel gases listed in Table II is presented in Table III below. The rela-tionship of the equilibrium oxygen concentration of 'he gas as monitored by the detector 30 after combustion, to the heating values of a variety of commercial fuel gases is graphically illustrated in Figure 3. The oxygen con-sumed is a linear function of the heating ~alue of the fuel gas as shown in the curves.
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13 49,334 ~hile the discussion has been directed to flow-ing gaseous fuel, the technique is equally applicable to other f lowing fuel media such as li~uids an~ solid fl~els including powdered coal supplied to a power plant.
An alternative embodiment of the heating value measurin~ techni~ue is illustrated in ~igure 4. The fuel gas/air mixing apparatus 20 and air source 22 of Figure 2 are eliminated and the fuel gas sample is supplied direct-ly to the catalytic sensing electrode 34 of the cell 30.
~n this embodlment, however, a voltage is applied across the cell 30 from a voltage source 38 to establish the cell 30 in a pumping mode o operation. The pumping action transfers o~ygen from the oxygen reference, i.e., air, at the reference electrode 35 through the cell 30 to the catalytic sensing electrode 3~ to combustibly react with the fuel gas sample from the supDly line 10. The transfer of oxygen through the cell 30 produces a cell current.
The current value corresponding to oxygen required to - effect the complete combustion of the fuel content of the fuel gas is measured by the BTU measuring circuit 50 as a measurement of the heating v~lue of the fuel gas. A fuel gas flow rate control apparatus 60 is employed to maintain the flow of the fuel gas to the detector 30 at a stable level and limit the flow to a level which will permit the cell 30 to effect complete combustion of the fuel gas at the catalytic sensing electrode 3~.
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9 49,334 ~or the purposes of discussion, consider a mixture of 5% Ca4 in air at typical conditions of tempera~
ture and pressure One liter of this mixture contains 0.05 24.4 liter/mole = 0.00205 mole of CH4. Complete combustion of this methane (C~4) reauires 2 x 0.00205 =
0.0041 mole 2' or 0.0041 mole x 24.4 liter/mole = 0.1000 liter oî 2 at room temperature and pressure. Thus, the 2 content of the original one liter o gas mixture would be reduced from 20% to 10%. Since, as illustrated above, the oxygen consumption during combustion is directly related to the heat content of a fuel, the measurement of the oxygen consumed, or that remaining, provides an indi-cation of the heat content of the fuel.
An implementation of this novel techni~ue for monitoring the heating value of fuel gases on khe basis of oxygen consumed during combustion is typicall~ illustrated in Figure 2. A sample of fuel gas from-a fuel gas supply - line 10 is supplied to a fuel gas/air mixing apparatus 20 which mixes the sample of the fuel gas with a predeter~
mined amount of a gas of stable oxygen content, i.e., air, to produce a fuel gas/air mixture which is supplied to a commercially available oxygen/measuring detector 30. The fuel gas/air mixture developed by the mixing apparatus ~0 is of a constant concentration with the concentration being adjustable in terms of the air introduced into _he mixing apparatus 20. While the fuel gas/air concert-ation mixture can be adjusted to optimize the sensitivity of the system for a particular heating value region, a 3 volume %
fuel gas/air mixture (97% air, 3% fuel gas) has been selected for the pur~ose o~ discussion. Tne air content, i.e., 97%, is typically chosen to assure sufficient oxygan to completely combust the fuel at the detector 30 and rasult in a residual oxygen in the mixture after combus-tion.
49'334 The oxygen detector 30 is illustrated as con-sisting of an electrochemical cell 32 having an oxygen ion conductive solid electrolyte element 33 with a catalytic sensing electrode 34 and an oxygen reference electrode 35 disposed on opposite surfaces thereof.
A furnace mPmber 36 maintains the electrochem-ical cell 32 at an operating temperature of between 800 and 1000C to optimize the oxygen ion conductivity of the solid electrolyte 33 and to assure a catalytic combustion reaction between the oxygen and fuel constituents of the gas mixture at the catalytic sensing electrode 34. The electrodes 34 and 35 are typically platinum electrodes with the platinum electrode 34 supporting catalytic com-bustion of the oxygen and fuel constituents of the gas mixture developed by the mixing apparatus 20. The result-ing decrease in the oxygen concentration of the gas mix-ture following the catalytic combustion reaction produces a change in oxygen partial pressure across the electro-chemical cell 32 and the resulting cell EMF is measured electrically by a BTU meter 40 which is connected to the electrodes 34 and 35 via electrical leads 42 and 43. The electrical signal measured by the BTU meter 40 is mani-fested as a measurement of the heating value of the fuel gas flowing in the fuel gas supply line 10.
The operation of the solid electrolyte electro-chemical cell 32 in both a pumping mode and in a potentio-metric mode is describe~ in detail in U.S. Patent No. Re.
28,792, which is assigned to the assignee of the present invention. The use of a solid electrolyte electrochemical cell of the type described in U.S. Patent No. Re. 28,792 is illustrated in detail in U.S. Patent ~os. 3,791,936;
4,134,818 and 4,190,499, all of which are assigned to the assignee of the present invention.
The amount of oxygen consumed, or that remain-ing, following the complete fuel combustion of 3 vo~ume %
~l~8(~9~
11 49,334 fuel gas/air mixtures, such as that produced by the gas mixing apparatus 20 of Figure 2, for the fuel gases listed in Table II is presented in Table III below. The rela-tionship of the equilibrium oxygen concentration of 'he gas as monitored by the detector 30 after combustion, to the heating values of a variety of commercial fuel gases is graphically illustrated in Figure 3. The oxygen con-sumed is a linear function of the heating ~alue of the fuel gas as shown in the curves.
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)-- ~o. ~1 O O ~ = _ ~0 O ~1 O ~ 3 3 .~
O >. O o cj _ O~ '7 N O
o '~ > ~,!
6 ' ~\1 ~ 0 11 Zo~t ~ Co _ Z._ . ` _ ~ C .~
U)o L
~ Z~' `: Z~
O ~ ~ _ . ~ O
L.~
V
< 0 L
-I o. ~ v "! no ~ C ~ V 3 V C~ :5 o _ ~ Q~ L
-- _ L ~! L. C~ L C~ " 3 L V O O t~
", Cc .L ~ LO ~
O ~-- ~> Q ~ ~ _ -- ~ Q O
;
13 49,334 ~hile the discussion has been directed to flow-ing gaseous fuel, the technique is equally applicable to other f lowing fuel media such as li~uids an~ solid fl~els including powdered coal supplied to a power plant.
An alternative embodiment of the heating value measurin~ techni~ue is illustrated in ~igure 4. The fuel gas/air mixing apparatus 20 and air source 22 of Figure 2 are eliminated and the fuel gas sample is supplied direct-ly to the catalytic sensing electrode 34 of the cell 30.
~n this embodlment, however, a voltage is applied across the cell 30 from a voltage source 38 to establish the cell 30 in a pumping mode o operation. The pumping action transfers o~ygen from the oxygen reference, i.e., air, at the reference electrode 35 through the cell 30 to the catalytic sensing electrode 3~ to combustibly react with the fuel gas sample from the supDly line 10. The transfer of oxygen through the cell 30 produces a cell current.
The current value corresponding to oxygen required to - effect the complete combustion of the fuel content of the fuel gas is measured by the BTU measuring circuit 50 as a measurement of the heating v~lue of the fuel gas. A fuel gas flow rate control apparatus 60 is employed to maintain the flow of the fuel gas to the detector 30 at a stable level and limit the flow to a level which will permit the cell 30 to effect complete combustion of the fuel gas at the catalytic sensing electrode 3~.
Claims (5)
1. A method for measuring the heating value of a flowing fuel medium, comprising the steps of, extracting a sample of said flowing fuel medium, combustibly reacting the fuel constituent of said flowing fuel medium sample with oxygen to deplete said fuel constituent, generating an electrical signal indicative of the oxygen consumed to deplete said fuel constituent, and measuring said electrical signal as a manifestation of the heating value of the flowing fuel medium as a function of the oxygen consumed during said combustible reaction.
2. Apparatus for measuring the heating value of a flowing fuel medium, comprising, means for extracting a sample of said flowing fuel medium, means for combustibly reacting the fuel constituent of said flowing fuel medium with oxygen to deplete said fuel constituent, and means for manifesting the heating value of the flowing fuel medium as a function of the oxygen consumed during said combustible reaction.
3. A method as claimed in claim 1 further including the step of adding oxygen to said flowing fuel medium prior to said combustible reaction, the amount of oxygen added being such as to assure the presence of residual oxygen after complete combustion of the fuel constituent of said flowing fuel medium.
4. A method as claimed in claim 1 wherein the relationship between heating value and oxygen consumption is linear.
5. Apparatus as claimed in claim 2 further including means for adding oxygen to said flowing fuel medium, the amount of oxygen added being such as to assure the presence of residual oxygen after complete combustion of the fuel con-stituent of said flowing fuel medium.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US26668481A | 1981-05-22 | 1981-05-22 | |
| US266,684 | 1981-05-22 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1180917A true CA1180917A (en) | 1985-01-15 |
Family
ID=23015582
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000402713A Expired CA1180917A (en) | 1981-05-22 | 1982-05-11 | Btu meter for monitoring the heating value of fuel gases |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS5821153A (en) |
| CA (1) | CA1180917A (en) |
| DE (1) | DE3219318A1 (en) |
| FR (1) | FR2506460A1 (en) |
| GB (1) | GB2099589A (en) |
| IT (1) | IT1158297B (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2539876A1 (en) | 1983-01-21 | 1984-07-27 | Pavlodarsk Ind I | Measuring heat losses due to incomplete fuel combustion |
| FR2542090B1 (en) * | 1983-03-01 | 1985-07-26 | Pavlodarsk Ind I | METHOD FOR DETERMINING CALORIFIED LOSSES BY IMBRULES AND DEVICE FOR IMPLEMENTING SAME |
| US4846081A (en) * | 1987-04-08 | 1989-07-11 | General Signal Corporation | Calorimetry system |
| DE3720684A1 (en) * | 1987-06-23 | 1989-01-05 | Bosch Gmbh Robert | METHOD AND DEVICE FOR MONITORING THE POLLUTANT CONTENT OF EXHAUST GASES IN INTERNAL COMBUSTION ENGINES |
| FR2626673B1 (en) * | 1988-01-29 | 1994-06-10 | Gaz De France | METHOD AND DEVICE FOR MEASURING THE HEAT POWER OF A VEHICLE BY A FUEL CURRENT |
| US5074987A (en) * | 1990-01-24 | 1991-12-24 | Elsag International B.V. | Online energy flow measuring device and method for natural gas |
| US5201581A (en) * | 1991-11-18 | 1993-04-13 | Badger Meter, Inc. | Method and apparatus for measuring mass flow and energy content using a linear flow meter |
| US5226728A (en) * | 1991-11-04 | 1993-07-13 | Badger Meter, Inc. | Method and apparatus for measuring mass flow and energy content using a differential pressure meter |
| US5323657A (en) * | 1991-11-04 | 1994-06-28 | Badger Meter, Inc. | Volumetric flow corrector and method |
| US5357809A (en) * | 1993-04-14 | 1994-10-25 | Badger Meter, Inc. | Volumetric flow corrector having a densitometer |
| DE102013202681A1 (en) | 2013-02-19 | 2014-08-21 | Continental Automotive Gmbh | Apparatus for determining a measure of a calorific value of a gas |
| DE102015107751B4 (en) | 2015-05-18 | 2018-05-17 | Uwe Lawrenz | Method and device for continuous calorific value measurement in process gases |
| JP6770622B1 (en) * | 2019-09-24 | 2020-10-14 | 東京瓦斯株式会社 | Calorimeter, calorimeter measurement method |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL7105976A (en) * | 1971-04-30 | 1972-11-01 | ||
| US4005001A (en) * | 1973-03-27 | 1977-01-25 | Westinghouse Electric Corporation | Combustibles sensor |
| FR2367285A1 (en) * | 1976-10-08 | 1978-05-05 | Charbonnages De France | METHOD AND APPARATUS FOR MEASURING THE OXYGEN CONTENT OF A GAS LANGE, SUCH AS AN ATMOSPHERE |
| IT1145264B (en) * | 1979-03-15 | 1986-11-05 | Ricardo Consulting Eng | APPARATUS AND PROCEDURE FOR DETERMINING THE CONCENTRATION OF THE AIR / FUEL MIXTURE SUPPLIED TO AN INTERNAL COMBUSTION ENGINE |
-
1982
- 1982-05-11 CA CA000402713A patent/CA1180917A/en not_active Expired
- 1982-05-20 GB GB8214784A patent/GB2099589A/en not_active Withdrawn
- 1982-05-21 IT IT41584/82A patent/IT1158297B/en active
- 1982-05-22 DE DE19823219318 patent/DE3219318A1/en not_active Withdrawn
- 1982-05-22 JP JP57087189A patent/JPS5821153A/en active Pending
- 1982-05-24 FR FR8208970A patent/FR2506460A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| IT8241584A1 (en) | 1983-11-21 |
| FR2506460B1 (en) | 1985-01-04 |
| IT1158297B (en) | 1987-02-18 |
| GB2099589A (en) | 1982-12-08 |
| JPS5821153A (en) | 1983-02-07 |
| FR2506460A1 (en) | 1982-11-26 |
| IT8241584A0 (en) | 1982-05-21 |
| DE3219318A1 (en) | 1982-12-16 |
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