JPH0768522B2 - How to detect the occurrence of joint kilns in coke ovens - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for detecting the occurrence of joint cutting kiln in a coke oven, which can promptly prevent the generation of black smoke from a chimney, and is suitable for a coke oven carbonization chamber. It enables furnace body management.

<Prior Art> Due to brick joint breakage in the carbonization chamber of a coke oven, the carbonization gas in the carbonization chamber leaks into the combustion chamber, resulting in incomplete combustion, and the carbonization temperature in the leakage part decreases. In this case, in order to increase the amount of heat input to the kiln, maintain dry distillation, and repair joint breakage, it is necessary to grasp the joint breakage situation promptly and accurately.

On the other hand, if the joint is cut off, partial dry distillation will be inadequate.Therefore, when the coke is discharged from the kiln, the pollution prevention equipment including the existing dust collector, which generates a large amount of dust, is incomplete, and the carbonization is incomplete. There is a lot of black smoke inside the coke oven chimney,
Since it is emitted over a long period of time, it is necessary to repair the joints in a timely manner from the viewpoint of pollution prevention.

Prior arts therefor include JP-A-54-41902 and JP-A-5-41902.
7-94085, there is a technology to detect the carbonization chamber where the joint is broken by detecting the relationship between black smoke due to incomplete combustion due to gas leakage to the combustion chamber due to the joint being cut and coal charging. It is disclosed.

At this time, the degree of black smoke generation is measured by the soot and dust densitometer to measure the amount of soot and dust in incomplete combustion, but the soot and dust densitometer is a relative value and absolute concentration cannot be detected. Further, although the attenuation of the projected light is detected, the density detection value is likely to change due to use because it is easy to get dirty, which often causes an erroneous operation, and the reliability of the detection accuracy is low. Moreover, since the dust concentration meter directly sucks the dirty gas, it is difficult to maintain the measuring instrument itself, and it cannot be used for a long period of time. further,
Since the dust concentration meter is strongly affected by the dust particle size and the exhaust gas temperature, the measurement error due to the properties of the exhaust gas from the coke oven is large and the measurement accuracy is low.

<Problems to be Solved by the Invention> The present invention proposes a method for detecting occurrence of a joint cutting kiln accurately, with good timing and easily.

<Means for Solving Problems> The present invention continuously extracts exhaust gas discharged from a combustion chamber of a coke oven from a flue, and measures and monitors SO ₂ concentration in the exhaust gas from which dust is removed by a filter, This is a method for detecting the occurrence of a joint cutting kiln in a coke oven, which is characterized in that the joint cutting kiln is generated when the measured value exceeds a predetermined control value.

<Progress and Effect of Invention> The inventors of the present invention have found that the S content of the carbonization gas is as high as 3500 to 5000 ppm,
When the leakage from the joint breakage occurs, SO ₂ of SO ₂ concentration in the exhaust gas is found that rapidly increases, also in the exhaust gas
The present invention has been made by paying attention to the fact that the concentration measurement is widely used from the viewpoint of pollution prevention and the maintainability and the measurement accuracy are well established.

An infrared analyzer can be used as the SO ₂ analyzer used in the present invention. Its measurement principle is to analyze the concentration by utilizing the fact that infrared rays are absorbed at a wavelength peculiar to the gas when infrared rays pass through the gas, and continuous measurement can be performed with high accuracy and at a low cost. Easy to maintain.

In the present invention, a non-dispersive infrared analyzer was used to fix a specific wavelength value representative of SO ₂ gas, and the SO ₂ concentration was continuously measured from the transmittance at that wavelength as follows.

FIG. 3 shows the situation in which the exhaust gas discharged from the combustion chamber of the coke oven is continuously extracted from the flue and sent to the infrared analyzer. That is, the gas sampling pipe 2 is exposed to the flue 1, the sampling gas is passed through the filter 3 to remove dust, and the essential gas amount is sent to the SO ₂ analyzer 6 by the pump 5. Pump by, by feeding collected gas continuously it is possible to constantly measure the SO ₂ concentration, can continuously monitor changes in SO ₂ concentration.

FIG. 2 is an overall view showing these SO ₂ concentration detecting means, and a signal indicating that the SO ₂ analyzer 6 for detecting SO ₂ in the flue 1 and the carburizing car 9 of the coke oven 8 have completed the carburizing completion is obtained. I am allowed to do so.

FIG. 1 is a flow chart for determining joint breakage, in which the SO ₂ concentration is under continuous measurement. Collect the charcoal signal of each kiln while detecting the SO ₂ concentration. Then, when compared with a predetermined reference value of SO ₂ concentration, that is, a control value or more, when the control value is exceeded, it is determined that a joint cutting kiln has occurred, and as a next work, a charcoal completion kiln at this time is found. It identifies the kiln where the joint is cut.

<Example> FIG. 4 shows the SO ₂ concentration measurement state in which a SO ₂ analyzer is permanently installed in the flue of a coke oven 1 furnace group having 39 carbonization chambers. In the figure, the passage of time shifts from the right to the left, and the SO ₂ concentration repeats increasing and decreasing at a substantially constant pitch.
Here, when the joint is broken, the carbonization gas in the carbonization chamber enters the combustion chamber, so that the SO ₂ concentration rises rapidly. An example is shown on the left side of the figure.

The concentration change is measured by measuring SO ₂ in the gas discharged to the flue side and using the normal SO ₂ concentration as a reference value.

As a result of continuous measurement, it was judged that the joint was broken when the concentration increased more than usual, and from the judgment result and the result of actual furnace monitoring, a rapid increase in SO ₂ concentration of 20% or more from the reference value occurred At times, it was found that it was possible to determine with high accuracy if the joint cutting kiln occurred.

Generally, when a kiln that cuts joints occurs, it shows a concentration of 20% or more from the normal time, and the high concentration continues for 10 minutes or more, and the peak of the high concentration of 20% or more from the normal time continues twice or more. Since there are many cases, it is almost impossible to overlook a joint loss.

Next, the joint cutting kiln is specified as follows. Charging pitch approx.
At 10 minute intervals, the increase in SO ₂ concentration due to joint breakage continues for about 30 minutes. After 30 minutes, it is presumed that the carbonization of the charged coal in the part in contact with the combustion chamber progressed, and gas leakage through the joint to the combustion chamber was interrupted. Therefore, based on the charcoal kiln when the SO ₂ concentration exceeds 20%, the charcoal kiln when the concentration changes and the charging 30 minutes before, the kiln is found and the joint is cut. In some cases, the joint cutting kiln can be specified almost accurately if the judgment is made by repeating this phenomenon twice.

Looking at the observation hole in the upper part of the combustion chamber of the specified kiln, the joint breakage has a lower temperature than other parts, so it looks dark and can be easily repaired.

<Effects of the Invention> Since the present invention can detect the occurrence of joint breakage immediately and reliably, it is possible to take prompt repair measures, achieve energy saving (reduction of dry distillation heat amount) in the coke oven, and achieve the life of the coke oven. Extension, and prevent black smoke generation and dust emission when receiving coke,
It greatly contributes to the prevention of pollution.

[Brief description of drawings]

FIG. 1 is a flow chart for detecting the occurrence of a joint cutting kiln of the present invention, FIG. 2 is an explanatory diagram for identifying the joint cutting kiln, and FIG. 3 is a situation of extracting exhaust gas for SO ₂ measurement from a flue. FIG. 4 is a conceptual diagram showing the above, and FIG. 4 is a measurement chart of SO ₂ concentration in exhaust gas. 1 ... Flue, 2 ... Gas sampling pipe, 6 ... Infrared analyzer (SO ₂ analyzer), 7 ... Discharge port, 8 ... Coke oven, 9 ... Charging car, 10 ... Chimney.

Claims (1)

[Claims] 1. The exhaust gas discharged from the combustion chamber of a coke oven is continuously extracted from the flue, and the SO ₂ concentration in the exhaust gas from which dust has been removed by a filter is measured and monitored, and the measured value is controlled in advance. A method for detecting the occurrence of a joint cut kiln in a coke oven, which is characterized in that a joint cut kiln is generated when the value exceeds a value.