DE2627429B2 - Process for the production of valuable lump coke from soft lignite according to the one-step process - Google Patents

Description

Method of making high who! igem Slückkoks from soft lignite 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-grain or fine-grain briquettes made from soft lignite are used degassed using the purging gas method at temperatures around 750 ° C. With simultaneous tar production falls a lignite coke with low strength, the volatile content and the Responsiveness is a low temperature coke.

Furthermore, a method for producing high-temperature lignite coke is known. the end Fine-grain briquettes produced without binding agents are made from soft lignite after flushing gas drying in indirectly heated vertical chamber furnace coked at temperatures up to about 1000 ° C. Due to the binderless When the soft lignite is briquetted on molding channel ram presses, the coke is just a shrink fit whose lumpiness and strength are limited. In this one-step process, the Coke quality not improved by briquetting of soft brown coal before degassing will.

It is also known that, in particular stone and Hanbraunkohlen, Feinkokse Briketlabrieb and briquetted with pitches or other bituminous products as well as Sulfiiablauge as a binder and thermally supplementarily at temperatures of about 200 to 250 ⁰ C. This process is a real binder briquetting, thereby

Ί marked that the binding forces that are decisive for the cohesion of the compact come predominantly from the binding agent. The mentioned coals or cokes can only be briquetted with great difficulty or cannot be briquetted without a binder. Such a real binder briquetting does not bring any advantages for the refinement of soft lignite. In addition, the ^{binder molds thermally aftertreated up to about 250 °} C. do not represent low or high temperature cokes.

It is also known that smoldering with mineral additives is also not advantageous. It is also known that in a binder briquetting with sulphite waste liquor by the addition of inorganic salts or inorganic acids, such as. B. Ca (OH) ₂ , HCl, MgCl ₂ , the ability of the sulphite waste liquor as a binder can be improved.

The purpose of the invention is to address the deficiencies shown in the degassing of soft lignite decrease while increasing the quality of the coke in terms of lumpiness and strength as well

2 ^r > Increase in the economic effect.

The invention is based on the object of using available briquettable soft brown coals Use of tools and using existing technological facilities as well

κι by modifying the technology to produce briquettes that are used in the known flushing gas degassing and result in the known high-temperature coking a coke that according to the conventional way generated in lumpiness and strength and surpasses

Γι thus better meet the requirements of the various Areas of application fulfilled.

According to the invention, this is achieved by adding a coking aid directly before the briquetting of the Dry lignite is added. Through this coking aid run in particular before, but reactions between the coal and during the degassing at the grain boundaries in the briquette bond the coking aid substance, which lead to the formation of a more stable shrink association. That Coking additives must be used in small amounts (between 2% and 10%, based on the total amount of briquetting) be distributed in the dry lignite before briquetting, so on all grain surfaces the reactions take place and no stress cracks which reduce the coke strength are formed can. Sulphite waste liquors and sulphite waste liquors dried to powder are suitable as coking agents ("Cell pitch"), sulfo resins and modified tars. The coking auxiliary sulphite waste liquor can in his

The effectiveness can still be activated essentially by the addition of small amounts, for example 2% H2SO4, HCl, sulfur and hydrochloric acid-containing waste products or salt solutions of these acids (e.g. MgCb solution).

M) The coking aid acts in the formation of briquettes not as a binding agent in the conventional way, because the binding forces for the strength of these special briquettes of the binderless soft lignite briquetting remain decisive, but rather the

h ^r> tool caused quality improvement affects only the coke. The briquettes produced with the coking aid reach the known degassing properties without intermediate or additional treatment.

directions. There, due to the high temperatures during the degassing (about 750 ^° C. or 1000 ^° C.), not only a coke with significantly higher strength is achieved, but also the vast majority of the sulfur and other organic compounds are removed from the coking aid.

According to the invention, the distribution of the coking aid with little effort and without Refinement of the briquetting coal grains can also be achieved in that part of the briquetting material premixed with the coking agent. The coal / coking aid mass ratio should be about 4: 1 to 2: 1, so that the mix in which the coking aid is present, remains free-flowing. This mixture is followed by the rest of the part of the briquetting material mixed homogeneously and then pressed.

^{In laboratory tests, the coke compressive strength of 153kp / cm 2} could be achieved using this process principle in the absence of coking aid z. B. to 297 kp / cm ² when using 5% sulphite waste liquor and 2% MgC! ₂ solution can be increased as a coking aid.

The invention will be explained in more detail below using an exemplary embodiment:

The electrostatic precipitator produced during the drying of the processed soft lignite in the tube dryer- ■> Dust is in an intensive mixer, also mills or disintegrators, with the coking agent in the Ratio 4: 1 to 2: 1 mixed homogeneously. The dusty and free-flowing mixture gets into a second mixing device, e.g. B. Mixing screw, vortex mixer, in which the mixing with the directly from the Operating section drying or that coming from the operating section dry coal treatment Dry charcoal is made. The result is a briquetting product that meets the conditions of fine-grain briquetting is equivalent to. The optimum proportion of the coking aid is preferably around 5%, if possible but less than 10%, based on the briquette. The Brikeltiergut goes directly to the molding channel punch presses (Briquette extrusion presses), in which there is

.'o temperatures of 70 to 80 ⁰ C as possible is formed into briquettes. The briquettes are transported directly to the degassing devices known per se.

Claims (4)

Patent claims: 1. Process for the production of high-quality lump coke from soft brown coal, in which the Coking agents are added to dry lignite, characterized in that that the coking agent is admixed directly to the briquetting material in an amount of 2 to at most 10% and that the briquetting of the free-flowing briquetting mixture obtained in this way means one Form channel punch press is carried out. 2. The method in particular according to claim 1, characterized in that the distribution of the Coking aid is achieved in that the coking aid is initially only with one Part of the briquetting material, preferably with the useful vapor dust, in a coal / coking aid mass ratio from about 4: 1 to 2: 1 is intensively premixed before this is still free-flowing Mixture in which the coking aid is already pre-diluted, among the much larger ones Portion of the briquetting material (dry lignite) is mixed. 3. The method according to claim 1 and 2, characterized in that as coking aids z. B. Sulphite waste liquor, sulphite waste liquor dried to powder and modified tars can be used. 4. The method according to claim 1 to 3, characterized in that the coking aids by adding small amounts of activating agents, for example 2% H2SO4 or HCl or other sulfuric acid or hydrochloric acid-containing waste products (z. B. sulfohar / s) and salt solutions of these Acids (e.g. MgCl ₂ solution) are activated.