DE2627429A1 - High grade lump coke mfr. - by mixing lignite with coking agent, briquetting and coking - Google Patents

Abstract

Mfr. of high grade lump coke from soft lignite consists of homogeneous mixing with 5-10% coking agent e.g. sulphite waste liquor, dried sulphite liquor (cellulose pitch) and/or sulpho-resin before briquetting and coking. Lumpiness of the coke is improved, and strength increased by addn. of coking agent which prevent formation of stress cracks in the coke, without acting as a conventional binder.

Description

Process for the production of high quality lump coke from soft brown coal according to the one-step process for the production of lumpy coke from soft brown coal two technologies are preferably used according to the one-step process.

In the first process, normal grains made from soft lignite are or fine-grain briquettes degassed using the flushing gas process at temperatures around 750 ° C.

With simultaneous tar production, a lignite coke falls with less The strength of the volatile constituents and the reactivity is a low temperature coke.

Furthermore, there is a method for the production of high-temperature lignite coke known. Fine-grain briquettes made from soft lignite are made without binding agents after purging gas drying in indirectly heated vertical chamber ovens at temperatures coked up to about 1000 ° C. Due to the binderless briquetting of the soft brown coal on molding channel punch presses, the coke is just a shrink fit of the Lumpiness and strength are limited. With this one-step The process cannot improve the quality of coke by briquetting soft lignite with binding agents can be improved prior to degassing.

It is also known that in particular hard and hard lignite, Fine coke and briquette dust with pitches or other bituminous products as well briquetted with sulphite waste liquor as a binder and at temperatures of approx. 200 to 250 ° C thermally solidified.

This process is a real binder briquetting, characterized in that the binding forces decisive for the cohesion of the compact predominantly originate from the binder. The mentioned coals or cokes are without Binder can only be briquetted with great difficulty or cannot be briquetted. Ptir the refining of soft brown coal Such a real binding agent briquetting does not bring anything that is distributed. In addition, ask the binder moldings that have been thermally aftertreated up to approx. 250 ° C are not deep or High temperature coke.

It is also known that the smoldering with mineral additives is not beneficial. It is also known that in a binder briquetting with sulphite waste liquor by adding inorganic salts or acids, such as Ca (OH) 2, HCl, MgCl2, improves the ability of the sulphite waste liquor as a binding agent can be.

The purpose of the invention is to address the deficiencies in the degassing of soft brown coal while increasing the quality of the coke in terms of lumpiness and strength as well as an increase in the economic effect.

The invention is based on the object of available briquettable Soft brown coals using tools and using existing ones technological facilities as well as through modification of technology To produce briquettes, which in the known flushing gas degassing and in the known High-temperature coking resulted in a coke that was produced in the conventional manner produced in lumpiness and strength and therefore better than the requirements of the various areas of application.

According to the invention, this is achieved by adding a coking aid very finely and homogeneously distributed, added to the dry lignite before briquetting will. Through this coking aid, insbe send ere run before, but also during the degassing at the grain boundaries in briquette bond reactions in the coal and in the coking aid substance from which to form a more stable Shrink bandage lead, which is also still through the finely distributed even coke frame of the coking aid residue is reinforced.

The coking aid must be used in small amounts (between about 5 % and 10%, based on the total amount of briquetting) and as very thin and as possible evenly on the grain surfaces of the dry lignite before briquetting are distributed so that the reactions take place and become on all grain surfaces also during the degassing between the coke shrink bandage that is being formed and the coke aid residue, no stress cracks that reduce coke strength can train. Sulphite waste liquors in powder form are suitable as coking agents dried sulphite waste liquors ("Zellpoch"), sulphonic resins and modified tars. The coking aid Sulphite waste liquor can be significantly reduced in its effectiveness by the addition of small amounts Quantities, for example 2% H2SO4, HCl, sulfuric and hydrochloric acid-containing waste products or salt solutions of these acids (e.g.

MgCl2 solution) can be activated.

According to the invention, the very fine and homogeneous distribution of the coking aid can be achieved with little effort and without too much refinement of the briquetting carbon grains e.g. can be achieved in that only a part of the 3rikettiergutes with the coking aid is intensively mixed. The coal / coking aid mass ratio should be be about 4: 1 to 2: 1, so that the mix in which the coking agent is already very diluted, remains free-flowing. This dusty mixture is then mixed homogeneously with the rest of the briquetting material and then pressed. The coking aid does not work in the formation of briquettes as a binder in a conventional manner, because of the strength of these special briquettes the binding forces of the binderless soft lignite briquetting remain decisive, but the quality improvement brought about by the coking aid only affects the coke. The briquettes produced with the coking aid get to the known degassing devices without intermediate or additional treatment. There, the high temperatures during degassing (approx. 750 ° C or 1000 ° C) not only achieved a coke with much higher strength, but also by far most of the sulfur and remaining organic compounds from the coking aid evaporated. This sulfur could then be recovered during gas cleaning.

In laboratory tests, the coke compressive strength was determined using this process principle from 153 kp / cm² when there is no coking aid, e.g. to 297 kpotcm when using increased by 5% sulphite waste liquor and 2% MgCl2 solution as a coking aid will.

The invention is to be described in more detail below using an exemplary embodiment explained: The one during the drying of the processed soft lignite in the tube dryer accumulating electrostatic precipitator dust is in an intensive mixer, also mills or disintegrators, mixed homogeneously with the coking aid in a ratio of 4: 1 to 2: 1. The dusty one and pourable mix enters a second mixing device, e.g.

Mixing screw, vortex mixer, in which the mixing with the direct from the drying operating section or from the dry coal treatment operating section coming dry coal is made. The result is a briquette that has the Conditions of the finest grain briquetting. The optimal proportion of the coking aid is preferably by 5 Gdf, if possible below 10%, based on the briquetting material. The briquetting material goes directly to the molding channel punch presses (briquette extrusion presses), in which it is formed into briquettes at press temperatures of 70 to 80 ° C if possible will. The briquettes are converted directly into degassing devices known per se transported.

Claims (5)

Patent claims: 1. Process for the production of high-quality lump koi 's from soft brown coal, characterized in that for the formation of a more stable coke association of the dry lignite small amounts (up to 10 ') of a coking aid are added directly, which can also be activated, the production of a homogeneous and fine Distribution of the coking aid achieved by pre-dilution and premixing and the briquetting of the free-flowing briquetting mixture on molding channel ram presses takes place, especially before, but also during the final degassing at the grain boundaries in the briquette bond reactions in the coal and in the coking agent substance as well as between the two, which lead to the formation of the more stable coke bond required are. 2. The method in particular according to claim 1, characterized in that that the required fine and homogeneous distribution of the coking aid thereby it is achieved that the coking aid initially only with a part of the goods to be labeled, preferably with derZ vapor useful dust, in the coal / coking aid mass ratio from about 4: 1 to 2: 1 is intensively pre-mixed before these table items, which are still risky, in which the coking aid is already pre-diluted, among the wide larger proportion of the briquettes (dry lignite) is mixed. 3. The method according to claim 1 and 2, characterized in that as Coking auxiliaries, e.g. sulphite waste liquor, sulphite waste liquor dried to powder and modified tars are used. 4. The method according to claim 1 to 3, characterized in that the Coking aid by adding small amounts Amounts of activating agents, for example from 2% H2SO4 or HCl or other sulfuric acid or hydrochloric acid containing waste products (e.g. sulfo resins) as well as salt solutions of these acids (e.g. MgCl2 solution) can be activated. 5. The method according to claim 1 to 4, characterized in that the Briquetting material containing coking agents, still free-flowing, to achieve high briquette strength is briquetted on a molding channel punch press.