DE2257668B1 - PROCESS FOR PRODUCING COAL COAL WITH INCREASED PIECE SIZE AND IMPROVED PIECE STRENGTH IN A HIGH PERFORMANCE HORIZONTAL FURNACE - Google Patents

Description

This result according to the invention must be described as extremely surprising because it It was expected that as the coking rate increased, as would the preheat causes, also according to the results in the high-performance furnace, an increase in coking progress is effected. Instead, with preheating, there was such a considerable reduction in the Coking progress achieved that now on the use of high-performance ovens because of the risk the production of coke that is too small no longer needs to be dispensed with.

This result is also in contradiction to older views, which are about an accelerated Heating and coking of the coal protect the bitumen and thus increase the strength the coke hoped to reach. Instead, by keeping the coking progress low, it straightens achieved the result that one hoped for from increased coking progress.

As was further found, one can see the coking progress also keep it low to a considerable extent and thus in the event of coking In high-performance furnaces, more coarse cokes can be obtained by placing larger chambers Width coked. The usual chamber width is 450 mm. To increase the coking rate chambers with a width of 350 to 400 mm have even been built. In contrast, one achieves according to the invention in high-performance ovens of the type defined at the outset, the desired low coking progress by coking in ovens with a chamber width of at least 500 mm.

Surprisingly, in high-performance furnaces of this type, at a high coking speed, a sufficiently low coking progress occurs, which leads to usable, namely large-sized and solid metallurgical cokes.

A combination of preheating the coking coal and coking in chambers a width across Understandably, 500 mm gives the greatest leeway for the creation of lumpy and sufficient solid cokes in high-performance furnaces also from coals with relatively poor coking properties.

Table 1 shows that as the heating draft temperature (HzT) rises, the coking progress in mm / h increases uniformly with the coking speed and the coke quality (in percent above 60 mm and drum strength M _{40) decreases.}

Table 1

Coking rate, mm / h

Coking progress,
° C / min

Coke <60 in percent ..

Drum strength M ₄₀ . .

Heating draft temperature 1200 I 1300 I 1400 I 1500

12.2

3.17 87.4

73.7

14.1

3.81 82.1 69.1

14.8

4.50 78.9 64.4

Table 2 below shows the effect of using furnace bricks of different thermal conductivity [silica (Sik) = 1.5 kcal / m / h / ⁰ C and ao magnesite (MG) = 3.0 kcal / m / h / ⁰ C at 1000 ° C] on the coking rate, the coking progress, the coke lumpiness and piece strength (drum strength).

Table 2

Coking rate, mm / h

Coking progress,
° C / min

Coke <60 in percent ..

Drum strength M ₄₀ ..

Stone material Sik I MG I Sik

Heating draft temperature, ⁰ C 1000 I 1000 I 1200 I 1200

9.4

1.66 95.9 86.4

14.1

2.85 89.0 81.4

12.5

3.0 90.3 81.5

Here, too, one recognizes the steady increase in coking progress with the coking speed with the transition to furnace stones higher thermal conductivity and the simultaneous decline in coke quality.

The importance of a low coking progress compared to an increased coking rate can be seen in the following Tables 3 and 4 recognize.

Tabel

wet preheated money wet preheated 1300 wet preheated Heating draft temperature 16.7 1200 1200 1300 3.78 1400 1400 12.2 14.1 13.6 85 14.8 18.8 Coking rate, mm / h 3.17 2.02 3.81 70.9 4.5 3.22 Coking progress, ° C / min 87.4 87.9 82.1 78.2 78.7 Coke> 60 in percent 73.7 74.1 69.1 64.4 64.5 Drum strength M ₄₀

Table 4 below shows the advantage of increased chamber widths for high-performance horizontal chamber furnaces.

2 257 668 6th -.5 Table 5 Table 4

Chamber-
broad Coking
progress
° C / min Coking
fast-
speed
mm / h Coke> 60
% Firming
. speed
M ₄₀ 300
400
450
500
600 5.8
4.8
4.2
3.5
2.4 16.0
15.7
15.5
15.4
15.2 29
37
41
45
53 58
65
70
73
81

170 220 265 Preheating temperature, ⁰ C

Coking speed.

mm / h

_xo coking progress, ° C / min ..

Coke> 60 in percent

Drum strength M ₄₀

13.0 2.52 81.8 69.0

13.9 2.30 82.2 69.0

Table 5 above shows the effects of various preheat temperatures and the. Advantage of preheating to 180 to 200 ⁰ C.

Claims (3)

1 2 r. and "also leads to a reduced" lump size coke. In a certain area, this patent claims: Reduction of the piece size is quite desirable, since it meets the requirements of the metallurgical industry on a 5 blast furnace coke with an upper limit of 1. Process for the production of hard coal coke piece size at about 80 mm. One increased piece size and improved piece strength - further increase in coking progress ability in high-performance horizontal chamber furnaces, but this can - and this is especially under consideration characterized that the view of the respective charcoal properties to coking at coking speeds of 15 io - to a piece size of the produced.Kokses up to 35 mm / h, in particular 18 to 35 mm / h, with. lead to the requirements of a blast furnace coke no longer corresponds to a coking progress of 1.6 to 3.3, d. that is, the coke becomes too small 2.2 to 2.8 ° C / mm (in the range of 350 pieces. up to 550 ° C) "is carried out ^.; As a result, the advantages of the high-performance 2. The method according to claim 1, characterized in that the coke oven is to a certain extent characterized by reduced quality in that the coking coal is destroyed again in the coke produced in the coke oven to temperatures of about 160 to be. With certain Kokskohlenqualitäten it is 25O ⁰ C, preferably about 180 to 200 ° C, not heated longer possible in a Hochleistungsöfen is for. Metallurgical industry to produce usable coke. Ver 3. The method according to claim 1 and 2, characterized in 20 coking speeds of over 15 to 35 mm / h characterized that the coking in ovens can lead to completely unusable Chamber width of at least 50mm through metallurgical coke. to be led. The invention is based on the knowledge that for the large size of the cokes and their strength 25 coking progress plays a decisive role. Coking advances above about 4 ° C / min, such as they set themselves automatically in high-performance ovens, lead to always with increasing coking progress coke that is becoming smaller and smaller 30 becoming strengths, it therefore depends on to influence the coking progress or: 'again to lower. "~ All measures to increase productivity · · According to the invention, the task of producing horizontal chamber furnaces is carried out. Increasing the firmness of lumpy cokes in the specific coking coal throughput in kg / m ³ / h leads to 3.5 mm / h, in particular 18 to 25 mm / h with a higher coking progress. The mean coking progress of 1.6 to 3.3, preferably coking speed is defined in mm / h, with 2.2 to 2.8 ° C / is guided by the required Garungs- 40 min in the range of 350 to 550 ° C by the half width of the chamber. This means that it is divided at high digests. the Verkokungsfortschritt will take .kokungsgeschwindigkeiten measures defined by the temperature rise in the plastic ¹ ', which the coking progress to below the range (350 to 550 ° C) in ° C / min - measured in the previously automatically setting values of e around the middle of the chamber. 4.0 ° C / min and above. By increasing the temperature of the heating flue, carbonization progression is slightly less pronounced the runner stone thickness and use of a step in the sense of a reduction can thereby Stone material with higher thermal conductivity will be achieved that in terms of coking coal shortening a certain selection has been made for the duration of the cooking and thus the composition rate increase; achieved, coking speed and is. Such efforts are very effective However, coking progress ^ does not show a rectified 50, and there are not always suitable ones Trend towards higher values; ,. , '·. "'. ' Coke coil grades available. The increase of the Heizzu'gtemperatuf to over'bis- 'According to the invention, on the other hand, was required as a long, extremely effective measure for the furnace construction to reduce valuable stone material ^:?; »- B. compacted silica, or the progress made, that in magnesite, the same "got" for the reduction of the 55 high-performance furnace, the above-mentioned for-runner stone thickness. Such high-performance furnaces can meet changes by the fact that the coke aims a shortening of the cooking time from previously coal before filling into the coke oven to temperatures of 20 to 24 hours to below 18, preferably 16 hours, temperatures of about 160 to 250 ⁰ C, preferably 180 down to about 8 hours. They put as a result up to 200 ⁰ C, heated. This preheating of the coking coal, which increases the productivity of the coke ovens 60 considerably beyond simple pre-drying and also increases the economy, surprisingly results in the possibility of coking. Coking progress in high-performance ovens is not that From operational practice as well as the upward trend mentioned by results, it is known that, surprisingly, extensive coking attempts remain in the area where an increase in coking progress leads to a decrease in the strength of the coke, which occurs in conventional ovens. As a result, coke can now also be produced in the case of higher common coke by the proportion over 40 mm after the coking speed of sufficient-drum sample (M ₄₀ ), as a result of the large size and strength.