JPH0483702A - Reformer for power generating unit of fuel cell - Google Patents

Abstract

PURPOSE:To improve reliability in sensing of the presence or absence of flames by providing an electromagnetic wave sensor directing to the flames of a pilot burner for igniting burners for heating the interior of a reforming furnace and sensing the presence or absence of the flames. CONSTITUTION:The subject reformer 1 is formed from a reforming furnace 5, a combustor 4 for heating the reforming furnace 5 to a prescribed temperature, an electromagnetic wave sensor 21, etc. The aforementioned combustor 4 is provided with main burners 8 and a pilot burner 7 for igniting the main burners 8. The above-mentioned sensor 21 is installed to direct to flames 9 of the aforementioned pilot burner 7 and electromagnetic waves produced from the flames 9 are sensed to sense the presence or absence of the flames 9.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a reforming device for a fuel cell power generation device that has a detection section that detects the presence or absence of a pilot burner flame of a pilot burner that ignites a main burner. .

[Conventional technology]

FIG. 5 is a configuration diagram showing the basic configuration of a fuel cell power generation device, and the fuel cell power generation device includes a reformer (1), a carbon oxide transformer (2), and a fuel cell main body (3). ing. The reforming bag W (1) includes a combustor (4) for maintaining the temperature of the reforming reaction and supplying reaction heat, and a reforming furnace (5) for steam reforming natural gas, which is a hydrocarbon fuel. .

When starting the fuel cell power generation system, first the combustor (4
) by burning a conventional fuel, such as city gas, to heat the reaction tubes (6) of the reformer (5) to a temperature sufficient for reforming. After reaching a predetermined temperature, the reformed raw material gas (city gas + steam) is introduced into the reaction tube (6), and the reformed gas reformed in the reformer (11) is transferred to the -carbon oxide shift converter ( 2) converts carbon monoxide into hydrogen and carbon dioxide, resulting in a fuel gas containing a large amount of hydrogen. This fuel gas is supplied to the fuel cell main body (3), and is filled with air (oxygen) as an oxidizer and an electrolysis chamber (not shown).
react through and get air output.

Within the fuel cell main body (3), hydrogen is consumed in proportion to the electrical output, and the exhaust gas becomes a low-calorie combustible gas containing 20 to 30% unconsumed hydrogen.

This is a low calorie flammable gas! The pond off-gas is again introduced into the combustor (4) of the reformer (1) to be combusted and used to supply heat for the reforming reaction. When burning with this battery off-gas, preliminary combustion with city gas is stopped. In this way, in a fuel cell power generation device, its reformer (1)
A combustor (4) is used that can burn anything from conventional city gas to battery off-gas.

Figure 6 shows the burner section of the combustor (4).

(7) is a pilot burner for igniting the main burner (8), and (10) is a flame detection electrode for detecting the flame of the pilot burner flame (9). Pilot burner (7
) is connected to a pipe that guides the fuel gas to the pilot burner (7), and pilot burner combustion air is blown into the vicinity of the pilot burner flame (9) at the same time as the fuel gas is introduced.

Next, the operation will be explained. During preliminary combustion in the reformer (1), a discharge electrode (not shown) discharges to the pilot burner (7), and fuel gas and air are introduced into the pilot burner (7). ) ignites. Regarding the burner flame, the flame detection electrode (10) inserted into the flame and the pilot burner (
7) By applying a voltage between the two, a current flows within the flame, and ignition is confirmed. Then the main burner (8)
The main burner (8) is ignited by introducing city gas and air into the tank and making contact with the pilot burner flame (9). After that, when the reformer (5) reaches the set temperature, the introduction of city gas to the main burner (8) is stopped, and the reforming raw material gas is introduced into the reformer (5).
The reformed gas passes through the fuel cell body (3) and returns to the main burner (8) as cell off-gas.

During this time, the main burner (
8) is not ignited. In addition, if the load suddenly changes, the balance between the reformed gas flowing into the fuel cell body (3) and the power generation load will be disrupted, and the extremely low-calorie cell off-gas will return, causing the main burner (8) to overflow. It may also misfire. For this reason, the pilot burner (7) must always be kept in the ignited state, and the reliability of ignition confirmation must be sufficiently high. Ignition detection is performed by applying a voltage between the pilot burner (A) and the flame detection electrode (10), detecting the current flowing therebetween, and comparing it with a set value.

[Problem to be solved by the invention]

In the reformer of a conventional fuel cell power generation device, organic matter contained in the cell off-gas is burned in the pilot burner (7) and main burner (8) and adheres to the flame detection electrode (10) as an insulator. (5) The dust from the insulation material causes a flame detection electric shock [! As a result of adhesion to the pilot burner (7),
) and the flame detection electrode (10), no flame current flows,
There was a problem in that the flame of the pilot burner (7) could not be detected.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a reforming device for a fuel cell power generation device that improves the reliability of detecting the presence or absence of a pilot burner flame.

[Means to solve the problem]

A reforming device for a fuel cell power generation device according to a first aspect of the present invention is provided with an electromagnetic wave detector directed toward the flame of a pilot burner.

Further, the reforming device for the fuel cell power generation device according to the second aspect of the invention is provided with first and second thermometers whose tips are located inside and outside the flame of the pilot burner, respectively.

[For production]

In this first aspect of the invention, the electromagnetic wave detector detects electromagnetic waves generated from the flame of the pilot burner, and the presence or absence of the flame of the pilot burner can be known.

Further, in the second invention, when the flame of the pilot burner disappears, there is no temperature difference between the outside and the outside of the flame of the pilot burner, and from this fact it is possible to know whether there is a flame or not.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, and the same or corresponding parts as in FIGS. 4 and 5 are designated by the same reference numerals, and the explanation thereof will be omitted. In the figure, (20) is an air pipe for sending air toward the pilot burner flame (9);
1) is an ultraviolet detector as an electromagnetic wave detector that is installed at the end of the air pipe (20) and detects the pilot burner flame (9) as ultraviolet light.

In the reformer of the fuel cell power generation device described above, fuel gas is introduced into the pilot burner (7) through the fuel pipe (11), and at the same time, air is blown into the vicinity of the pilot burner (7) through the air pipe (20). The pilot burner (7) is ignited at the same time as the ignition discharge electrode discharges to the pilot burner (8). At this time, the ultraviolet detector (21) detects the pilot burner flame (9).
It detects the ultraviolet rays emitted from the lamp and issues an ignition signal.

In addition, the heat resistance temperature of the ultraviolet detector (21) is generally 100℃.
℃, and if dust adheres to the detection part, the amount of ultraviolet light transmitted will decrease and false detection will occur.When using an ultraviolet ray detector, the detection part is generally air purged to cool the detection part. Although dust adhesion is prevented, according to this embodiment, the pilot burner (7) is always ignited when the row temperature in the reforming furnace (5) of the converter (1) increases, and the pilot Since the combustion air flows to the detection part, it is possible to cool the ultraviolet detector 21) and prevent dust from adhering to the inside of the reforming furnace (5).

FIG. 2 is a cross-sectional view of a main part showing an embodiment of the second invention of the present invention, and in the figure, (30) has its tip located at the pilot burner flame (9) as shown in FIG. The first thermocouple (31) serves as a thermometer, and the second thermocouple (31) serves as a thermometer, the tip of which is located outside the pilot burner flame (9).
This is a thermocouple.

In this case, the temperature difference between the pilot burner flame (9) and its outside is about 250°C, as shown in Figure 4, and on the other hand, when the pilot burner flame (9) is extinguished, the pilot burner flame (9) Since there is no temperature difference between the inside and outside of the
1), it can be seen that the pilot burner flame (9) has disappeared.

In the embodiment of the first invention, the ultraviolet detector (21) is provided coaxially with the air pipe (20), but the ultraviolet detector may be coaxially provided with the fuel pipe. Further, although an ultraviolet detector is used as the electromagnetic wave detector, the present invention is not limited to this, and for example, an infrared detector may be used.

Further, in one embodiment of the second invention, a thermocouple is used as the thermometer, but of course the thermocouple is not limited to this, and for example, a resistance thermometer may be used.

〔Effect of the invention〕

As explained above, according to the reformer for the fuel cell power generation device of the first aspect of the present invention, the presence or absence of the pilot burner flame can be detected by the electromagnetic wave detector, so that the This has the effect of improving reliability because it is not affected by organic combustion products.

Further, according to the reforming device for the fuel cell power generation device according to the second aspect of the present invention, the presence or absence of the pilot burner flame can be detected by a thermometer that detects the temperature inside and outside the flame, respectively. Similar to invention 1, this invention has the effect of improving reliability.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of a reforming device for a fuel cell power generation device according to an embodiment of the first invention of the present invention, and FIG. 2 is a reforming device for a fuel cell power generation device according to an embodiment of the second invention. 3 is a diagram showing the relationship between the pilot burner flame and the thermocouple in Figure 2, Figure 4 is a diagram showing the temperature inside and outside the pilot burner flame, and Figure 5 is a diagram showing the fuel cell power generation. A schematic configuration diagram of the apparatus, FIG. 6 is a sectional view of essential parts showing an example of a conventional reforming apparatus. In the figure, (1) is the reformer, (4) is the combustor, and (7) is the reformer.
) is the pilot burner, (8) is the main burner, (9)
is the pilot burner flame, (21) is the ultraviolet detector, (
30) is a first thermocouple, and (31) is a second thermocouple. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (2)

[Claims] (1) A reformer that reacts hydrocarbon fuel with steam to produce reformed gas, and a combustor that heats the inside of the reformer to a predetermined temperature, including a main burner and a pilot burner that ignites the main burner. A reforming device for a fuel cell power generation device comprising: an electromagnetic wave detector that is provided facing the flame of the pilot burner and detects electromagnetic waves generated from the flame to detect the presence or absence of the flame. Reformer for power generation equipment. (2) A combustor that heats the inside of the reformer to a predetermined temperature, including a reformer that reacts hydrocarbon fuel with steam to produce reformed gas, and a main burner and a pilot burner that ignites the main burner; In the reformer of the fuel cell power generation device, the first and second thermometers have tips located inside and outside the flame of the pilot burner, respectively, and detect the presence or absence of the flame based on the temperature difference between the inside and outside of the flame. A reforming device for a fuel cell power generation device, comprising: