JPH07269851A - Oxygen analyzing device - Google Patents

Abstract

PURPOSE:To provide an oxygen analyzing device by which the distribution of an oxygen concentration in a boiler or furnace can be obtained by real time for the purpose of a highly efficient operation of a boiler and an early detection of an abnormality of a combustion condition in a furnace. CONSTITUTION:An oxygen analyzing device consists of a plurality of analysis meters 2-5 which are provided in the width direction of a boiler. Then, each analysis meter is constituted of an oxygen analysis unit wherein a plurality of oxygen sensors 2-1:2-4-5-1:5-4 are arranged on one probe tube, and oxygen concentration signals can be simultaneously obtained from the plurality of oxygen sensors, and an operation processing unit 6 which processes the signals from respective oxygen sensors which are simultaneously obtained at the oxygen analysis unit and operates the distribution of an oxygen concentration, and a display unit 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxygen analyzer used in a boiler for a thermal power plant that uses coal, heavy oil, LNG or the like as a fuel, and particularly for high efficiency operation of the boiler and early detection of abnormal combustion state in a furnace. Therefore, the present invention relates to an oxygen analyzer capable of obtaining an oxygen concentration distribution in a furnace in real time.

[0002]

2. Description of the Related Art Conventionally, various types of devices for controlling combustion in a thermal power plant boiler using coal, heavy oil, LNG or the like as fuel have been known, for example, Japanese Examined Patent Publication No. 4-9970.
The publication discloses a technique of arranging a plurality of remote mobile or switching gas analyzers in a furnace, measuring CO / O ₂ distribution, and displaying the result on a CRT. On the other hand, as an apparatus for simultaneously measuring oxygen concentrations at a plurality of points, the applicant of the present invention, for example, in Japanese Patent Laid-Open No. 1-250753, attaches a plurality of oxygen sensors to one probe tube, and places different in depth direction. Disclosed is a technique for simultaneously measuring the oxygen concentration of the.

[0003]

However, in the technique disclosed in Japanese Patent Publication No. 4-9970, the oxygen concentration in the furnace is sequentially measured at a plurality of locations arranged by a remote type or switching type gas analyzer. Then, after memorizing in the memory circuit, the oxygen concentration distribution is measured by CRT at the time when all the points have been measured.
Is displayed. Therefore, it takes a long time to measure all points, and since all points cannot be measured in real time, there is a problem that an oxygen concentration distribution is formed by data at different times. Further, in the above-mentioned technique, if it is attempted to measure all the points at the same time, there is a problem that the gas suction and the equipment cost of the analyzer are required.

On the other hand, the technique disclosed in Japanese Patent Application Laid-Open No. 1-250753 can simultaneously measure the oxygen concentration at different points in the depth direction, but there is no disclosure about processing the data, and the present invention is not limited to this. However, there was a problem that simultaneous and continuous measurement of oxygen concentration distribution in the target boiler could not be performed accurately.

The object of the present invention is to solve the above problems,
It is an object of the present invention to provide an oxygen analyzer capable of obtaining the oxygen concentration distribution in the furnace in real time for high-efficiency operation of the boiler and early detection of combustion state abnormality in the furnace.

[0006]

The oxygen analyzer of the present invention has a plurality of oxygen sensors arranged in one probe tube.
Calculate the oxygen concentration distribution by processing the signals from the oxygen analyzer that has multiple analyzers that can simultaneously obtain the oxygen concentration signals from multiple oxygen sensors and the oxygen sensors that are simultaneously obtained by this oxygen analyzer. It is characterized by comprising an arithmetic processing unit for performing.

[0007]

In the above-mentioned structure, by disposing a plurality of oxygen sensors in one probe tube and disposing a plurality of analyzers capable of simultaneously obtaining oxygen concentration signals from the plurality of oxygen sensors in the boiler. By configuring the oxygen analyzer, the oxygen sensors can be arranged in a grid pattern with respect to the boiler cross section, and the oxygen concentration distribution in the boiler cross section can be obtained in real time by simultaneously obtaining the oxygen concentration from each oxygen sensor. It can be displayed on the CRT without using such means.

Further, since the oxygen concentration distribution information of all points can be continuously obtained in real time, the balance of the combustion state inside the boiler can be grasped at the time of the combustion (burner) adjustment performed after the boiler regular inspection. Not only can it be used as a support tool for combustion adjustment, but leakage of seal air from the penthouse, etc. during boiler operation, combustion change (abnormality) due to improper combustion adjustment, etc. were obtained in real time, and the oxygen concentration distribution and optimum combustion state were obtained. It can be easily detected by simply comparing it with the oxygen concentration distribution in (1), and the occurrence of an abnormality can be notified. Also, combustion change (abnormal)
The same effect as described above can be considered for readjustment at time.
Furthermore, the oxygen analyzer is of a direct insertion type, and its measurement data can also be automatically recorded in the recording device, so that work on site for oxygen distribution measurement is not required.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing the structure of an example of the oxygen analyzer of the present invention. In FIG. 1, 1 is a boiler, 2-5 are analyzers arranged in the width direction of the boiler 1, and the analyzers 2-5 constitute an oxygen analyzer. Further, the analyzers 2 to 5 have oxygen sensors 2-1: 2-4-5 to the probe tubes 2a to 5a.
1: 5-4 are arranged at regular intervals. Therefore, the oxygen sensor 2-1: 2-4 to 5-1: 5-4
Can be arranged in a grid pattern in the cross section of the boiler 1.

Further, reference numeral 6 is a calculation for processing signals from the oxygen sensors 2-1: 2-4 to 5-1: 5-4 obtained at the same time by the oxygen analysis unit to calculate an oxygen concentration distribution of the boiler 1. A processing unit, 7 is a control unit that controls the operation of the boiler 1 based on the oxygen concentration distribution obtained by the arithmetic processing unit 6, and 8 is a display unit that displays the oxygen concentration distribution obtained by the arithmetic processing unit 6.

FIG. 2 is a diagram showing an example of the display result of the oxygen concentration distribution on the display section 8 of the oxygen analyzer of the present invention.
In the example shown in FIG. 2, the oxygen sensors 2-1: 2-4-5.
Based on the oxygen concentration in 1: 5-4, the arithmetic processing unit 6 performs image processing such as interpolation to connect the oxygen concentrations with a line and display the distribution. In the present invention, this oxygen concentration distribution can be continuously displayed in real time on the display unit. Then, by comparing the oxygen concentration distribution thus measured with the oxygen concentration distribution in the optimum combustion state or the oxygen concentration distribution in the abnormal state prepared in advance, the information for the combustion control of the boiler 1 and the abnormality Can detect.

FIG. 3 and FIG. 4 are views showing the constitution of an example of analyzers 2 to 5 of the oxygen analyzer of the present invention. In FIGS. 3 and 4, 11 is a probe tube (2a to 5 in FIG. 1) inserted and installed in the flow of the combustion exhaust gas which is the gas to be measured.
A plurality of oxygen sensors 20 (corresponding to 2-1 to 5-4 in FIG. 1) are attached to the probe tube 11 inside the filter cover 12 at predetermined intervals. In addition, the filter cover 12 is provided so that the oxygen sensor 20 can be attached to and replaced with the probe tube 11.
An opening is formed in the probe portion facing to the sensor back cover 13 and is covered therewith.

When the oxygen sensor 20 is attached or detached, the sensor back cover 13 is removed, and the oxygen sensor is attached and detached through the opening. The oxygen sensor 20 is arranged at a predetermined distance in the axial direction of the probe tube 11, and the predetermined interval is generally 50 cm or more. At the base of the probe tube 11, a mounting flange 15 and a terminal box 18 are provided.
Is attached to the furnace wall flange 16 provided on the furnace wall 17 by the mounting flange 15 and fixed.
The terminal box 18 is provided with wiring and piping holes 19.

An air outlet 14 is provided at the tip of the probe tube 11, and, for example, air (atmosphere) as a standard gas continuously introduced into the probe tube 11 via an air valve (not shown) is used. The air is emitted continuously from the air outlet 14.

FIG. 4 shows the mounting structure of the oxygen sensor to the probe tube 11. In FIG. 4, a bottomed cylindrical oxygen sensor 20 made of a solid electrolyte is arranged so that the space inside the bottomed cylinder and the space for combustion exhaust gas flow communicate with each other at a predetermined mounting position of the probe tube 11 (that is, bottomed). A cylinder and an opening are arranged (toward the flue gas stream). To attach the oxygen sensor 20 to the probe tube 11, first, a sensor fastener 21 is attached around the opening of the cylindrical bottomed oxygen sensor 20.
Is hermetically fixed by, for example, a shrink fitting method, and the sensor holder 22 fitted to the probe tube 11 of the sensor fitting 21 is attached.
It is made by tightening and fixing it to a metal O-ring 27.

The oxygen sensor 20 mounted in this way
In addition, a double-cylindrical heater holder 24 (which constitutes a heater unit) having a built-in heater 23 is fitted into the sensor fastener 21 from the inside, and is integrally fixed by cement bonding. Therefore, the oxygen sensor 20, the sensor fastener 21, the heater 23, and the heater holder 24 (that is, the heater unit) form an integrated structure to form a sensor unit.

On the side of the oxygen sensor 20 exposed to the gas to be measured, a filter 2 is provided to prevent dust from flowing in.
5 and the filter holder 26 are fitted together, and the filter cover 12 is provided on the outside of the filter unit to prevent direct dust from hitting the filter 25 and prevent clogging of the filter 25. . By the way, the filter cover 12 is provided with, for example, four measurement gas inflow holes 34 equally divided at an angle of 90 degrees so that the measurement gas can be introduced into the oxygen sensor through the filter 25. There is.

Further, in order to calibrate the output (that is, electromotive force) of the oxygen sensor 20, a calibration gas introducing pipe 28 introduced from the outside of the furnace wall is arranged along the outside of the probe pipe 11, and the calibration gas introducing pipe 28 is calibrated. The opening 29 is attached to the sensor holder 22.
The gas inlet / outlet 35 provided in the filter holder 26 is connected to the calibration gas introducing pipe 30 provided in the internal space 3
A gas passage communicating with No. 1 is formed so that the calibration gas is introduced into the internal space. The sensor holder 22 is provided with a gas outlet 32 on the side opposite to the side on which the calibration gas inlet 30 is provided. Further, the filter holder 26
A gas passage 33 is formed on the circumference of the filter holder 26 by processing the corners of the filter holder 26 which are in contact with each other.

The gas passage 33 connects the internal space 31 and the external measured gas space via the gas inlet / outlet port 35 and the gas outlet port 32, and also to the internal space of the calibration gas inlet pipe 28. The calibration gas introducing ports 30 communicate with each other. Therefore, the measured gas and the calibration gas existing in the internal space 31 can be quickly discharged to the outside.

[0020]

As is apparent from the above description, according to the present invention, a plurality of oxygen sensors can be arranged in one probe tube, and oxygen concentration signals can be simultaneously obtained from the plurality of oxygen sensors. Since the oxygen analyzer is configured by arranging multiple analyzers in the width direction of the boiler, the oxygen sensors can be arranged in a grid pattern with respect to the boiler cross section, and the oxygen concentration can be obtained from each oxygen sensor at the same time. The oxygen concentration distribution can be obtained in real time and can be displayed on the CRT without using any means such as a memory circuit.

Further, since the oxygen concentration distribution information of all points can be continuously obtained in real time, the balance of the combustion state inside the boiler can be grasped at the time of the combustion (burner) adjustment performed after the boiler regular inspection. Not only can it be used as a support tool for combustion adjustment, but leakage of seal air from the penthouse, etc. during boiler operation, combustion change (abnormality) due to improper combustion adjustment, etc. were obtained in real time, and the oxygen concentration distribution and optimum combustion state were obtained. It can be easily detected by simply comparing it with the oxygen concentration distribution in (1), and the occurrence of an abnormality can be notified. Also, combustion change (abnormal)
The same effect as described above can be considered for readjustment at time.
Furthermore, the oxygen analyzer is of a direct insertion type, and its measurement data can also be automatically recorded in the recording device, so that work on site for oxygen distribution measurement is not required.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an example of an oxygen analyzer of the present invention.

FIG. 2 is a diagram showing an example of a display result of an oxygen concentration distribution on the display unit of the oxygen analyzer of the present invention.

FIG. 3 is a diagram showing a configuration of an example of an analyzer of the oxygen analyzer of the present invention.

FIG. 4 is a diagram showing a configuration of an example of an oxygen sensor of the oxygen analyzer of the present invention.

[Explanation of symbols]

1 Boiler, 2-5 Analyzer, 2a-5a Probe tube, 2-1: 2-4-5-1: 5-4 Oxygen sensor, 6
Arithmetic processing unit, 7 control unit, 8 display unit

Claims (1)

[Claims] 1. An oxygen analyzer having a plurality of oxygen sensors arranged in one probe tube and provided with a plurality of analyzers capable of simultaneously obtaining oxygen concentration signals from the plurality of oxygen sensors,
An oxygen analyzer comprising: a processing unit that processes signals from each oxygen sensor obtained at the same time by the oxygen analysis unit and calculates an oxygen concentration distribution.