CS269443B1 - Method for determining the temperature of the outer heating channel of the heating wall of a coke oven - Google Patents

Abstract

The method of determining the temperature of the outer heating channel of the heating wall of a coking furnace to achieve the formation of plastic deposits with sealing ability consists in setting the temperature of the outer heating channel and maintaining a constant temperature at least during the coking period, while during the third coking period the time course of the temperature of the door frame contact surface is measured and at the end of the third coking period a sample of deposits is taken from the door frame contact surface at the location of the measured temperature of the door frame contact surface, in which the softening temperature of the sample is stabilized and the temperature of the outer heating channel is adjusted.

Description

The invention relates to a method of determining the temperature of the heating channel of the heating wall of coking furnaces of coke oven batteries operating with a loose or compacted coal charge based on determining the softening temperature of tarry deposits on the frame of the coking chamber and the temperature of the frame at the point of taking a sample of the deposit.

The current method of temperature condition of coke ovens is commonly carried out by measuring the temperatures of specified heating channels and calculating the temperature of the coke oven battery from the temperatures thus obtained. For more thorough control and adjustment of the temperatures of the heating channels, the temperatures of all heating channels of the entire heating wall of the coke oven are measured, in order to achieve suitable conditions for coking the coal charge in the coking chamber. These measurements have so far served only to achieve optimal coking conditions, at which high quality coke is achieved.

When operating coke oven batteries, there are cases when tarry deposits leak through door leaks, stick to door seals and door frames, flow under the doors and contaminate coke oven work platforms and packaging machines when handling the doors. In other cases, tarry deposits become hard, coked, which insufficiently seal the coking chamber doors. Thin plastic and rigid coked deposits create difficulties in their cleaning. When handling the doors and cleaning the surfaces on which the deposits settle, the operator is exposed to adverse working conditions. Interventions carried out in the management of coke oven and battery operations to achieve a suitable quality of deposits that would not pollute the workplace too much and could be easily cleaned are carried out without in-depth analysis, based only on practical experience, thus not achieving suitable conditions for limiting the release of pollutants containing carcinogenic components.

The above-mentioned shortcomings are significantly reduced by the method of determining the temperature of the outer heating channel of the heating wall of a coking furnace to achieve the formation of plastic deposits with sealing ability, according to the invention. Its essence lies in the fact that the set temperature of the outer heating channel is maintained at a constant level for at least three coking periods, while during the third coking period the time course of the temperature of the door frame contact surface is measured and at the end of the third coking period a sample of deposits is taken from the door frame contact surface in the area of the measured temperature of the door frame contact surface, in which the softening temperature of the sample is determined and the temperature of the outer heating channel is adjusted. The usual methods and equipment available in coke oven operations determine the temperature of the outer heating channel, the door frame temperature and the softening temperature of the tarry deposits sealing the coking chamber door. The measurements thus yield three factors that are interconnected in the system: the temperature of the heating channel, the door frame temperature, the formation of tarry deposits, the quality of the tarry deposits, of which the controlling element of this system is the temperature of the outer heating channel.

The advantage of the method of determining the temperature of the outer heating channel of a coke oven to achieve a suitable quality of deposits on the sealing surfaces of the frame and the door of the coke chamber according to the invention is its simplicity, when using the currently used laboratory equipment of the coke oven. The temperature of the outer heating channel is measured with a pyropter, the temperature of the frame from the outside close to the door sealing element with a contact thermometer, a sample of deposits is taken from a defined section of the frame, and the deposits are analyzed in the laboratory to ensure the softening temperature of the deposit in °C according to Kraemer-Sarnow. By gradually adjusting the temperature of the outer heating channel - until the required quality of deposits is achieved - the optimal temperature of the outer heating channel is obtained in a given operating state of the coke oven and with the coke charge used.

The temperature of the outer heating channel is set and maintained at a constant level for at least three coking periods; the temperature is measured at appropriate time intervals to obtain its time course during the three coking periods, with a sample taken at the end of the third coking period.

CS 269 443 Bl rek deposits. Care is taken to ensure that the door is placed coaxially on the coking chamber in order to eliminate the influence of asymmetrically placed doors with different widths of gaps between the door lining and the furnace head lining. In the last (third) coking period, the temperature profile of the frame is measured with a contact thermometer in order to obtain a temperature record in the Sas dependence. The temperature profile of the outer heating channel and the frame is compared in order to determine whether there were inappropriate fluctuations in the temperature of the outer heating channel (the outer channel affects the temperature of the frame with a delay). After opening the door, a sample of deposits is taken from the adjacent section of the frame, namely that part of the deposits that was inside the sealed space on the frame contact surface. The sample is taken in the area of the measured temperature point of the frame, the height of the section must be precisely determined and cleared before the chamber is occupied so that deposits are collected for only one coking period. When taking the sample, its condition is assessed, namely whether it is deposits:

- rigid brittle, * -

- dense plastic, - plastic soft, - thin, - dense with semi-coke).

* semi-coke.

The evaluation of the obtained data will indicate what kind of deposits were obtained - appearance, softening point °C according to Kraemer-Sarnow, at the temperature of the furnace and the outer heating channel. By repeating the measurement at the adjusted temperature of the outer heating channel, the goal is achieved, to obtain dense plastic deposits with the greatest sealing ability, which after opening the chamber and taking the sample quickly pass into a solid brittle state, that is, the character of hard pitch. In this way, it is determined for a given coal charge at what temperatures of the frame the appropriate quality of deposits is obtained and what temperature of the outer heating channel must be reached and maintained.

The method of determining the temperature of the outer heating channel according to the invention is explained in more detail using a specific example.

Three operational measurements in the coke oven adjusted the temperatures in three groups of four adjacent outer heating channels so that in the section of chamber No. 303 the temperature of the outer heating channels was 1,210 °C, in No. 310 the temperature of the outer heating channels was 1,100 °C, in No. 317 the temperature of the outer heating channels was 920 °C. After two coking periods, in the third coking period in the section of chamber No. 303 the average temperature of the outer heating channels was 1,106 °C, in No. 310 the average temperature of the outer heating channels was 1,02Γ °C, in No. 317 the average temperature of the outer heating channels was 910 *0. The average temperatures of the contact surfaces of the door frames during the third coking period were in chamber No. 303 - 185 °C, No. 310 - 167 °C and No. 317 - 148 °C.

From the results of laboratory processing of the collected samples of sealing deposits, changes in the content of volatile flammable substances, substances insoluble in benzene, softening point in °C according to Kraemer-Sarnow and dependence on the temperature of condensation points and coking time were monitored. The quality of sealing deposits can be suitably expressed by the dependence of the softening point measured in °C according to Kraemer-Sarnow. ’

The analysis showed that the softening temperature of deposits increases with the increase in coking time and with the temperature of the condensing plates. The graphical dependence of the change in the softening temperature of deposits on the temperature of the condensing surfaces and the coking time shows that at the temperature of the place of sampling of sealing deposits within the limits of 100 to 174 °C, the softening temperature of deposits within the limits of

CS 269 443 Bl

J. 00 to 170 °C according to Kraemer Sarnow.

Visual monitoring of chambers δ. 303, 310, 317 during the third coking period showed that problems with tarring of the doors were manifested in chamber δ. 303, when a tarry substance splashed onto the threshold platform when the chamber was opened, and partly in chamber δ. 310. In chamber δ. -317 with the lowest temperature in the outer heating channel, the aforementioned problem of tarry substance spilling out when the chamber was opened did not occur, and the deposits on the sealing surfaces had the character of hard pitch - after removing the door they were hard - brittle with a softening temperature of around 130 °C according to the Kraemer-Sarnow method.

This method can be used to determine the temperature of the outer heating channel, to find the optimal conditions for the formation of deposits when putting the coke oven battery into operation, further when changing the charge and finally for quick control of the temperature state in the outer heating channels, to achieve high door tightness.

Claims (1)

SUBJECT OF THE INVENTION A method of determining the temperature of the outer heating channel of the heating wall of a coking furnace to achieve the formation of plastic deposits with sealing ability, characterized in that the set temperature of the outer heating channel is maintained at a constant level for at least three coking periods, while during the third coking period the time course of the temperature of the door frame contact surface is measured and at the end of the third coking period a sample of deposits is taken from the door frame contact surface at the location of the measured temperature of the door frame contact surface, in which the softening temperature of the sample is determined and the temperature of the outer heating channel is adjusted.