JPS6131816A - Combustion state monitoring device - Google Patents

Abstract

PURPOSE:To perform effective adjustment and check of a combustion furnace and maintain a low excess-air combustion state of combustion furnace by a method wherein, plural gas analyzers of either remote-movable type or switching-over type are provided in outlet port of fuel (coal) economizer or the like to measure gas distribution of CO, O2, while measured results are indicated by CRT in the central control room. CONSTITUTION:The CRT is provided in the central control room so as to always perform measurements of the gas distribution of CO, O2, while a probe 2 for analyzing flue gas is arranged in a flue 1 which incorporates with a movable gas analyzer 8 in a remote operative place. As an alternative shown on the figure, the probe 2 is separately arranged from the analyzer 8 to induce and measure the flue gas through switching-over by remote control, and its data is memorized in a memory circuit, thereafter the analyzed values are indicated under corresponding state of a burner thereof, together with a comment on adjustment of the burner. Namely, it is possible to give the remarks to operator saying e.g. ''opening degree of air resistor is deviated from the predetermined level'' or the like.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a combustion furnace such as a boiler composed of a multi-burner, and in particular to a combustion furnace that enables high efficiency operation by keeping the excess air ratio in exhaust gas low. The present invention relates to a combustion state monitoring device for a furnace.

[Background of the invention]

Boilers and the like that burn fossil fuels such as coal, oil, and gas are required to operate with as low an excess air ratio as possible from the viewpoint of improving plant efficiency and preventing low-temperature corrosion. however,? , - Lou 1?
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-1-1ql/ry, and in most cases consists of a multi-burner system,
Even if a combustion failure occurs in any burner among the multi-burners, a full color of smoke will occur, so the system is operated at an excess air rate of about 7 to 15% of the theoretical combustion wall air volume. In a burner system consisting of multiple burners,
■Effects of product manufacturing errors, pressure loss of air and fuel, and difference in branch loss during the early stages of construction; ■After construction, wear and tear on the fuel side due to differences in operating hours between burners; ■Burning, deterioration, and clogging of some parts, etc. Combustion of individual burners and between burners is affected by deterioration factors. Conventional low-excess air combustion methods include equipment improvements such as atomization of atomizers, ■ adjustment mainly based on combustion status investigation through visual monitoring inside the furnace, and ■ traverse of CO and O2 in the flue based on input. In particular, in order to cover up product variations, the burner air register adjustment and burner inspection are carried out based on the observation inside the furnace described in (■) above, and the burner is inspected. We have been working to achieve low O2 combustion by setting optimal conditions. The latter's CO,
Although O2 traverse is effective in determining adjustment guidelines, it requires a large number of analysts and time, resulting in a large amount of cost, so traverse meetings are conducted for demonstration rather than adjustment. The reality is that this is often the case. Furthermore, low excess air combustion is particularly required from the point of view of effective energy use due to the recent rise in fuel costs. Combustion with a high excess air ratio was often performed.

[Purpose of the invention]

The purpose of the present invention is to eliminate the drawbacks of the conventional low excess air combustion method described above, and to make it possible to reduce the excess air ratio in exhaust gas in a central control room even without special skill, and to continue stable combustion operation. The object of the present invention is to provide a combustion state monitoring device that can achieve high efficiency operation.

[Summary of the invention]

The present invention is a combustion furnace such as a boiler that uses fossil fuels such as coal, oil, gas, etc. and is composed of a multi-burner. They measure the distribution of CO and O2, display the measurement results on a CRT in the central control room, and determine which burner among the multi-burners has a bad air ratio or combustion condition. Comments are made on the horizontal pipe at the adjustment point, and changes over time and load are also displayed to effectively perform adjustment inspections based on these comments.
This is a combustion state monitoring device that can maintain low excess air combustion.

[Embodiments of the invention]

The combustion state monitoring device of the present invention will be explained based on an embodiment. FIG. 1 illustrates the overall configuration of a boiler. In the furnace 6, the fuel that is jetted out from the fuel pipe 15 through the fuel flow control valve 16 and atomized in the burner 5 and the combustion air that is supplied from the wind box 4 through the air preheater 3 through the blower 1 are mixed and combusted. 14 flames are formed. The flame 14 is a multi-burner flame, and strictly speaking, it forms a group of flames in which there is an imbalance in air flow rate and fuel flow rate between burners. Conventionally, the excess air rate has been measured, for example, by using an 02 analyzer 9 installed in the flue at the outlet of the economizer 8, as a representative point in the flue, or as an average value obtained by analyzing about three points.
has been controlled by programmatically controlling the load by adjusting an air-controlled damper. Additionally, as shown in Figure 2.3, there is a distribution of Co and 02 in the flue of the actual machine due to the imbalance of air and fuel between the multi-burners and the leakage of seal air from the penthouse 11, etc. 02 is low i.e. C
It is already known that unburned carbon, that is, soot and dust, is generated in places where O is high because the fuel becomes hot and oxygen-deficient. Furthermore, from the results of basic experiments and actual machine analysis, we found that C
It is easy to think that the flow of O and 02 towards the outlet side of the furnace 6 is disturbed by the existence of the superheater 7 and the economizer 8, which are composed of a group of tubes, and the flow is mixed and averaged out, but in reality, most of the The situation of the multi-burner group in the furnace, which corresponds to the burner air ratio, can be observed in almost the same way. (See Figure 4) Therefore, if the combustion condition deteriorates due to changes over time after initial combustion adjustment, analyze and measure the C0,02 distribution in the flue, and based on this result, for example, perform the measurements shown in Figure 2.3. If the data is selected, based on the concept shown in FIG. 4, the air register can be adjusted to increase the amount of air to the right side at the rear of the boiler can.

The present invention enables the above-mentioned analysis to be performed inexpensively and easily without relying on human power, and also enables operators to read the measurement results and take appropriate measures. A CRT as shown in FIG. 6 is arranged so that the C0,02 distribution can be measured at any time. That is, as shown in FIG. 5, an exhaust gas analysis glove 2' is placed in advance in the flue 1'.

The analyzer 8' integrated with the probe is moved remotely, but the probe 2' and analyzer 8' are separated, gas suction is remotely switched, measured, stored in the memory circuit, and then the 6th analyzer is moved.
Display as shown. Furthermore, this analysis value is displayed in correspondence with the burner, and adjustment comments are also displayed at the same time. This kind of CRT is
Another way to use it is as shown in Figure 7, an example of which is to make it possible to display an audible display of how the distribution is changing over time or depending on the load. For example, by making it possible to compare and contrast with the situation at the time when low excess air combustion operation was possible,
Is a particular bus burnt or worn out, so check it out? It takes. ”, ■1 There is a setting discrepancy in the air register opening. ”,■[Penthouse leakage and deterioration is severe. Comments such as J can be notified to operators, and by taking measures according to these comments, low excess air operation is always possible. In other words, highly efficient operation is possible. Also, based on the displayed signal, the air register opening degree, etc.
By setting the opening angle of the rodanba in the wind box from the center,
This makes it possible to adjust combustion without going to the site.

〔Effect of the invention〕

As described above, according to the present invention, low excess air combustion can be continued by immediately taking appropriate measures against changes over time, thereby improving the efficiency of the boiler. In addition, since changes over time can be quantitatively understood, it is possible to further improve the 02 value. By displaying the measurement results and comments thereon, it is possible for anyone to perform adjustments, inspections, etc. in the same way and easily, without the need for a person who is particularly skilled in combustion adjustment. Furthermore, the analytical measurement itself is simple and the cost required for the measurement is low.

Fig. 4 is a distribution diagram of the analysis results of CO502 in the exhaust gas, and shows the relationship between the burner and the Co and O2 in the exhaust gas.

6...furnace, 9...02 analyzer, io...representative detection point, 1'...flue tact, 2'...probe, 3
'... Non-metal tongue for horizontal movement, 4'... Horizontal movement actuator, 5'... Vertical movement actuator, 6
'・Protection tube, 7'...Switching valve, 8'...Analyzer.

Agent Cormorant Numa Tatsu Figure 1 Figure 2 Figure 3 Figure 5

Claims (5)

[Claims] (1) In combustion furnaces such as boilers that use fossil fuels such as coal, oil, and gas and are equipped with multi-burners, multiple remote mobile or switching gas analyzers are placed in the flue, such as at the outlet of the boiler economizer. A combustion state monitoring device characterized by measuring the distribution of CO and O_2 and displaying the measurement results on a CRT in a central operation room. (2) The scope of claims characterized by determining the burner position corresponding to the distribution of CO and O_2, and displaying on a CRT an expression urging adjustment of the combustion air amount of the corresponding burner and inspection of the burner. The combustion state monitoring device according to item 1. (3) The combustion state monitoring device according to claim 2, wherein an air register opening/closing signal is automatically issued based on the combustion air amount adjustment signal. (4) The fuel condition monitoring device according to any one of claims 1 to 3, wherein the CO and O_2 distributions are stored in a memory circuit, and changes over time and changes in load are displayed on a CRT. (5) Based on changes over time and load, the CRT displays information such as selecting the optimal burner pattern, guidelines for repairing the penthouse, and guidelines for inspecting or replacing burners for abnormalities (wear, burnout, clogging, etc.). Claim No. 4
Combustion condition monitoring device as described in section.