DE2639899A1 - High-quality lump coke from non-coking coal - by briquetting under high pressure and coking without oxidative preheating - Google Patents

Abstract

Prodn. of high=grade lump coke from non-coking or low-coking coal involves crushing to fineness of 1/0 mm., homogeneous mixing with binder pref. in amt. of 7.5-12% briquetting under high press. of 600, pref. 1000 kp/cm2 min. at a temp. dependent on the binder, and coking with rapid heating, pref. at 30 degrees K/min., without previous thermal oxidn. The binder may be pitch, but also suitable are high boiling and asphalt-rich tar and oil-processing products which cannot be used for normal briquetting and coking. Organic waste prods., esp. scrap rubber, may be mixed with the binder to improve its properties. Stability of the briquettes is improved and volatilisation of the binder during heating-up reduced, so that odixative pre-heating of the briquettes is eliminated. Costs are reduced and economic use made of water materials, e.g. scrap tyres. which can be emulsified in the binder, e.g. coal tar, in ratio 1:3-10.

Description

Process for the production of high quality

Lump coke from hard coal that does not bake or bakes only weakly The invention relates to a process for the production of high-quality lump coke from non-or only weakly baking hard coal.

It is known that only such hard coals make a piece of fresh coke which have sufficient coking capacity. Such coal will be with a grain size of 3.15 / 0 mm to 8/0 mm, mostly horizontal and isolated also coked in vertical chamber furnaces. In this coking process, the hard coal is used mostly poured into the coking chamber without pre-compression. In much less The amount of coal is tamped before it is fed into the coking chambers slightly pre-compressed. It is also known that the coking behavior of Bituminous coal with increasing Grain fineness improved. The grain fineness there are limits, however, because the greater the fineness of the coal, at the same time their bulk or "tamped density" is reduced, which affects the performance the coking plants and has a negative effect on the strength of the coconut. The bulk density the sole is isolated by adding oil or other bituminous products tried to increase. However, the success of such measures is low.

It is also known that the coking behavior is less caking Hard coal by adding tar pitch or high-boiling oil distillation residues can improve. In addition, it is known that there are also relatively uncomfortable Lump coke can be produced if the coal has previously been given a grain size of about 4/0 mm mixed with tar pitch or high-boiling petroleum distillation residues read binder briquetted on roller presses with pressures of 200 to 400 kp / cm2 is and these briquettes before the actual coking process by oxidative thermal Treatment at temperatures around 250 ° C are thermally stabilized. Without a previous one Thermal stabilization of the binder compacts does not result in a high quality Lump coke, because the binding agent still forms a stable coke bond runs out of the briquettes or distilled off. In addition, the compacts lose their original shape value completely during the heating-up period. A piece of coke is only obtained if the coal already has a very good coking capacity disposes. In this case, however, prior briquetting is uneconomical.

Low-boiling products such as B. Coal tar are suitable for this process does not act as a binder, because this already occurs during the oxidative thermal Distill off the pretreatment of the pellets or run out of the briquette bandage.

In addition, methods are known for -denen fine coke or non-baking Bituminous coals with a low content of volatile components together with good baking ones Bituminous coals are briquetted by hot briquetting at press temperatures above 400 ° C and subsequently coked. Briquetting can also be done with a suitable Binders can be made at temperatures between 60 and 120 ° C. In both Cases, however, are shares of expensive baking hard coals of usually more than 30 S necessary.

It is also known that the coking capacity of hard coal improved with increasing heating rate. An increase in the heating rate are, however, with the previously common horizontal or

Vertical chamber furnaces set limits because of the heat transport through the low thermal conductivity of the heated ones, which are mostly made of silica material Chamber walls and, above all, within the poured or tamped coal is relatively low and leads to coking times of over 16 hours. The heating up the hard coal can be accelerated according to known methods by that the coal is already preheated in the coking chambers filled. this however, requires additional equipment. On the other hand, the heating rate can be increased by applying the flushing gas coking. The use of the principle of Purge gas coking requires the use of lumpy coal or briquettes and sets In an additional process step, an oxidation of the lump coal or a thermal stabilization ahead of the briquettes.

The purpose of the Brfindung -is to the identified deficiencies in the coking of non-baked or only weakly baked hard coal with simultaneous Increase the quality of the coke in terms of lumpiness and strength as well Increase in the economic effect.

The invention is based on the object of developing a method - after the non-baked or low-baked hard coal, a lump of coke with a high Strength can be generated economically advantageous.

According to the invention, this is achieved in that the non-or only Low-baking hard coal to a technical grain size of, for example, 1/0 mm comminuted and after uniform admixture of, for example, 7.5 to% binder under high pressure at the optimal compression temperatures depending on the type of binder is briquetted from approx. 80 to 120 ° C on suitable presses. The pressure should be are advantageously in the range between 600 to 1000 kp / cm2.

Suitable as presses. preferably mold roller presses. According to the invention is achieved by compressing such fine-grained coal with a very high compression pressure the binding agent so tightly enclosed in the briquette bandage that the otherwise usual The binder escapes during the heating-up period before the actual coke formation phase is very strongly suppressed. These finest grain briquettes are produced under high pressure at the same time have good dimensional stability during thermal heating.

According to the invention, the binder can be distributed homogeneously further stabilize in the briquette bandage during the warm-up period and the thermal The dimensional stability of the compacts can be further improved if the highly compressed fine-grain briquettes be subjected to rapid heating.

It is according to the invention through the production of binder compacts made of non-baked or only weakly baked coal with a grain size of 1/0 mm and finer Using high pressure combined with rapid heating of the briquettes, possible without a Jusitzli process stage for an oxidative thermal pretreatment for the purpose of thermostabilization of the binder compacts in a short coking period to produce a very strong coke with high shape value. This is mainly because of this possible because of the homogeneous distribution through the combination of different active principles of the binder up to the actual coke formation phase even without oxidative thermal Pretreatment of the compacts is largely retained, which removes the binder Solid-state bridges formed during coking to form a continuous solidified hard lump coke can contribute.

At the same time, the newly developed coking process still offers the Advantage that even then from non-baking or only weakly baking hard coal without additional oxidative thermal pretreatment of the compacts a very solid piece of coke can be produced when briquetting binders with the consistency of coal tar be used. According to the invention, this process is also suitable as a binder z. B. pitch, all high-boiling and asphalt-rich tar and petroleum processing products and faded bitumen. In addition, a mixture has proven itself as a binding agent, which can be achieved by emulsifying scrap rubber from used car tires in coal tar at a tar / gum mass ratio of about 3: 1 to 10: 1, according to the invention waste products that were previously wasted can be put to useful use again.

The invention is explained below using two exemplary embodiments wdrden.

Example 1: Lump coke is made from the following components: 92.5% hard coal with a grain size of 1/0 mm with 36% volatile components (wafer) 7.5 % Propene bitumen.

After a homogeneous mixture of the components, a briquetting takes place on a trough roller press with precompaction at a pressure of around 70 ° C carried out. The briquettes are then subjected to rapid coking when heated to 600 ° C to 1000 ° C in 100 min. The cooled lump coke has the following properties: Shape retention: 100% drum strength: R 30 84.8% (according to 300 revolutions in IfB drum with 500 mm) volatile components: (what) 0.20% Sulfur content: (waf) 1.14% Example 2: A piece of coke is made from the following components Manufactured: 90% hard coal with a grain size of 1/0 mm with 36% volatile components (waf) 10% coal tar / old rubber mixture (ratio 6: 1).

The rubber portions of z. 3. Old car tires are in liquid coal tar emulsified. This modified binder is mixed with the fine coal at a temperature mixed homogeneously at 70 ° C. The briquetting and coking takes place as in the example 1.

The cooled lump coke has the following properties: Shape retention: 100% sulfur content: (waf) 1.02% drum strength: R30 93.0% (after 300 revolutions in IfB drum) Refug. Components: (wafer) 0.32% Report on the publications on the state of the art: 1. Gresskin-sky: O. Handbuch des Kokereiwesens, Vol. I, Düsseldorf, Karl Knapp Verlag, 1955 2. Kozina, A, Pisa, M.

Splichal, B.

Kokaavenatvi Praha 1973, SNTL-Nakladstelstvi technicke literatury Nakaldatelstvo ALFA, n.p.

Bratislava 3. Schmidt, J. Technology of Gas Production Vol. I, Degassing and coking Leipzig, D @. Verlag f. Basic industry, 1964 4. Agrosking, A.A. Expansion of coal resources for the coke industry Hoskva, Motallurgizdat 1962 5. Syskoy, K.I.

Masenkov, O.N.

Thermokislitelnoje koksovanije uglej Moskva, "Metalurgija" 1973 6. Welz, E. Briquetting BHT coke breeze with soft lignite pitch as a binding agent for the production of large-sized molded coke Frbg. Research-H. A491 (1971), pp. 57-92 70 Patent 1C a, 22/07 73 749

Claims (3)

Claims 1. Process for the production of high quality lump coke from hard coal which does not bake or bakes only weakly, characterized in that the following Technology is applied in a complex way by using a thermally not pretreated coal Crushed to a fineness of at least 1/0 mm, with binding agents in proportion from preferably 7.5 to 12 so homogeneously mixed, depending on the binder Pressing temperatures and under high pressing pressures of 600 kp / cm2, preferably 1000 kp / cm2, briquetted and these compacts subsequently without intermediate thermal oxidation be coked by a subsequent rapid heating of preferably 30 K / min. 2. The method according to claim 1, characterized in that as a binder especially for this complex technology in addition to the conventional pitches the high-boiling and asphalt-rich materials that have so far only been insufficiently suitable as binders Tar and petroleum preproducts as well as coal tar without further refinement can be used directly. 3. The method according to claim 1 and 2, characterized in that organic Waste products, preferably old rubber, for the binders mentioned in claim 2 are mixed in, which significantly improves the binder properties.