DD213575A3 - PROCESS FOR PROCESSING BROWN COOK TINERS - Google Patents

Abstract

The invention relates to a process for the processing of oxygen-rich brown coal tars. The aim of the invention is to hydrate stabilize thermally unstable brown coal tar and thus to expand the possibilities of recovering valuable lignite. According to the invention, the lignite coal tar is treated at elevated pressure and elevated temperature with CO / H deep or CO / H deep / H deep O mixtures. This resulted in a reduction of the oxygen groups of the tar with simultaneous hydrogenation. The resulting product is undecomposed distillable and can be further processed by the known methods to paraffins, lubricating oils and / or fuels. The invention can be applied in chemical lignite processing plants and hydrogenation plants.

Description

Title of: Invention

Process for processing brown coal tars

Field of application of the invention

The invention relates to a method for processing brown coal tars., Especially from Kokerei- and generator tars from säuerst off rich .. Lignite

Characteristic of the known technical solutions

The ¹ in the. Brown coal tars are a valuable interim certificate, which must be converted into liquid and solid fuels by further processing into oils and solid paraffin, or by hydrogenation into liquid fuels as well as the solid constituents (dusts). and liberators, the relative value of the particular brown coal tar is limited by its content of creosote, olefins, asphaltenes and resins.

The Krepsote are sour-sourced compounds with an acid character. They arise in the thermal destruction of humic acids and acid-containing. .Bitumenanteilen, and are characterized by a high proportion of functional Säuerst off groups. In addition, neutral oxygen compounds, especially ketones, occur in the tar.

The. Structure of the. The asphalt contained in the tar is still poorly understood. These are high molecular weight compounds containing oxygen and sulfur, with predominantly arsenic character, known as. Result of a, incoming. Polymerization or Po.lykondensätionsreaktibn between corresponding bitumen components, such as the o · g. Creosote, result of a thermal action on the ^: decomposing coal constituents are .. Their composition, and chemical reactivity can vary greatly; Because of the strong tendency to polymerize and usually difficult hydrogenation they are regarded as unwanted / constituents. The content of these two groups which impair the further processing of the tar are determined by:

- the technology used in lignite pyrolysis (especially with regard to maximum temperature and residence time),

- the nature of the coal used (especially with regard to the acid content).

Accordingly, the find. These groups of substances mainly in generator and Koke ^ e.iteereh, which were subject to high thermal stress. On the raw material side, xylitic and acid-rich lignites, such as those of the East Elbe district, produce tar with high creosote and asphaitic contents.

The following average analytical values are measured (з RAMMLER / von ALBERTI; Technology and chemistry of the lignite recycling; VEB German publishing house for basic industry, Leipzig j962):

Spülgasschwer- '

tar / "EiGR _- ?

Saxony

Revxeic

Druckver *

gassing

tar

Bohlen

Coke oven / "EGR _- ?

Low-

lausitzer

territory

Asphaltenes / resins Third 9 3.8 1.1 2 M-Si creosote 9 2 9.0 20 2 paraffin 17 2 u.b. 12 5 ш-%

At the same time, the brown coal Kokereiteere due to increased thermal stress due to a comparatively high G _e halt of olefins / "44 M -% _ 7 'and aromatics /"1.6 МІ -% _ 7 characterized i

In the context of conventional lignite processing, the existing and difficult to hydrogenate asphalt constituents are separated by distillative removal of the lower boiling constituents by the pumice action in coke and. split gaseous decomposition products. When. In addition, the liquid and solid sugar hydrocarbons, which are subsequently processed appropriately, are obtained.

Due to their high content of.functional.oxygen groups (creosote), to the progressive. Polymerisate _: ionising asphalt contents and the proportion of unsaturated compounds lead coking plant?:: And. Generate place from acid first of oak lignite.for the distillative further processing to malfunctioning coke deposits. These result from thermally induced polymerisation and precipitation condensation reactions, which are primarily caused by the very: more reactive, more functional, oxygen-containing groups of unsaturated compounds.

On. The presence of dust in the form of cohesive ash and ash will end up in the future. Polymerisationsprodukte-. Bound. And increased the Koksan.teil, these deposits lead to the relocation of plant components and to block catalysts ·

Particularly unstable are the East Elbe lignite cokers. A hydrogenating stabilization and subsequent working up by known processes the hydrogenation of coal by the action of molecular hydrogen ¹ resulted because of the requisite .Reaktionstemperaturen of about 350 ⁰ C to no useful result. The processing of such unstable and dust-carrying lignite coal tar is therefore despite the considerable amount of valuable material a previously unsolved problenu

Object of the invention

The aim of the invention is a method for processing brown coal tar,. with the the. under thermal stress prone to i'eststoffbildung. Brown coal tars, mainly dusty Kokerei- and generator tars from brown coal of the East Elbe territory are changed so that a subsequent workup possible wir.d and. The possibilities for recovering valuable material from lignite are to be extended accordingly.

For the purpose of the invention.

The invention is based on the object, previously with the. Processing of brown coal tannins associated disadvantages and the Nichtbearbeitbarity of Ostelbischen lignite coke overeer overcome.

It was found that. that of a distillative or hydrogenating workup by means of molecular hydrogen previously inaccessible unstable. Brown coal ducks 'excellent in', Veise a chemical stabilization by means of CO / steam or ..

CO / H ₂ / steam mixtures, are accessible. It has been plagued that the hitherto regarded as disadvantageous, high reactivity of the functional oxygen groups and unsaturated bond portions favorable conditions for a СО-reaction bei.niedrigen process pressures and temperatures allowed. With that .will; a conversion that achieves the instability-causing creosote and olefins before thermally induced coke formation occurs. According to the invention, the reaction process is displaced in the region of reduced temperatures, thereby favoring the following properties of the named reaction gas.

favorably influencing the ¹ chemical equilibrium of the C 0 -conversion reaction i

- increasing solubility: · ^of: carbon monoxide, it igphase in the river ;.

On the face of the opposite. ' Hydrogen use has a greatly shortened reaction time in practical operation, stabilizing reactions; already in parallel to the heating phase. According to the invention, the 'supply of the CO / steam or CO / I-Lp-Dainpf mixture already takes place during the heating of the tar, namely at tempera tures, which are below that leading to the formation of solids. Temperature of the relevant Teerbestandteile lie. To ..Warranty .; ,one . adequate stabilization effect is the average heating rate in the critical temperature range of; 100 to 350 ⁰ C to a maximum of 10 ⁰ C / min limit. At the same time, local heating-up excesses are avoided in this heating-up regime.

The possibility of "carrying out the stabilizing reaction during the heating up phase" is not applicable . Έά the tar is, taking into account the time required, for the coke-forming reactions as quickly as possible, with as much as possible avoidance of coke deposits (eg. High flow velocity) to the reaction temperature: to bring the oil / vapor or CO / I / vapor agitation.

The to be set. React ion temperature depends on the chemical composition of the feedstock and the СО content in the hydrogenation gas. It is in the range of 200 to 500 ⁰ C ,. preferably 300 to 400 ° Gj The process pressure is below 25 MPa. It is. also possible. the heating regime under appropriate process pressure and in the presence of the stabilizing CO / steam or ' CO / H ₂ / steam mixture from the outset to connect with the.destillativen workup. In this Pail the accumulating individual fractions are Bedarfsweis.e in: follow-up individually further stabilize.

Due to the permissible high final temperatures, the subsequent hydrogenating cleavage and / or. Conditioning by means of molecular hydrogen. or CO / steam or * CO / Ho / steam mixtures bsi tempera door en- \ above 350 ⁰ C, either directly or. can be connected nach.einer Zwischenge> ohaiteten distillative workup · According to different treatment of the '. in the starting product .evtl. be present dust. These can be either before. According to the processing according to the invention, it is separated directly into the subsequent hydrogenation with additional recovery of carbon values. v / eräen. In addition, the targeted admixture of additional, eeinkohleanteile in zweckentsprechendem place des.Yerfahrensganges possible.

The. Stabilization and subsequent hydrogenation and / or conditioning by molecular! / Hydrogen or CO / steam or CO / Ho / steam mixtures, can be carried out init or without addition of catalyst.

In addition to the Stabilisierungsreäktionen the proposed inventions. Reaktionsmili.eu Changes in the groups of substances contained in the tar, which lead to an improvement in value extraction. This is what it is. u .. a. following effects':

- reduction, the oxygen content it,

- Formation of an asphaitic portion, which, although quantitatively higher than that of the untreated tar, is a consequence of the high content of resulting acid-substance bridges, in deviation from the usual hydrogenation behavior at elevated temperatures in low molecular weight recyclables' is largely accessible.

The method according to the invention has the following procedural advantages;

- the information contained in the kondenslerparen products.The Braunkohlenent- and gasification ^and: dust particles difficult to separate can. one, be used directly. Thus tarry products with increased dust contents, which have not yet been processed, can be utilized. Catalytic effects can be expected from existing ash fractions.

- The proportion of water contained in the tar products and, because of its emulsifying effect, which is difficult to control in terms of process engineering, can be used directly as a reaction partner.

- the.insurance.it. from. Ver, gas or .Synthesegasen offers that. Prerequisite'for suitably speaking interconnected operation.

embodiment

The invention is to be explained below with reference to an exemplary embodiment, in which it is represented on a laboratory scale.

50 g of a mechanically cleaned lignite high temperature tar were brought to reaction temperature together with 30 g of water in a rotary autoclave of 1 1 content under OO atmosphere. The default final pressure was established by setting a defined carbon monoxide cold pressure. The average heating time up to the respective final temperature was 90 minutes. After reaching the final temperature, the cooling was immediately noted ». At 300 ⁰ C was relaxed. The following chemical changes were detectable on the reaction product.

Final pressure not 20.0 21.0 5.5 MPa

2nd temperature is 350 375 375 ⁰ C

liquid products 98 3 94.8 85.9 84.1 T.I.S. - distillate 0 > ° 6.1 10.8 7,4 №- # - Maltene '94 ,8th 73.8 62.8 68.6 M- "S - asphaltenes 3 , 5 14.9 12.3 10.1 м-: '

oxygen content 5, 15 4 80 2 , 87 3 , 9 mr% - Maltene 16 69 8th , 58 8th , 87 7 , 6 K- ⁶ S - asphaltenes

n paraffins (total) 10 19 ^C 10 * ^C 25 C ₂₀ - с 26 * C

21.3 18 , 4 18.9 20.7 iX'S 0.0 0 , 0 0.2 1.1 M-iC 0.7 1 , 0 5.4 7.6 Γ /.- Ϊ5 7.3 6 2 8.1 3.8 m-; s 13.3 11 2 5.2 3.2

Resin content in tar 35.8 24.3 15.7 15 ,? И-Я (in the Maltenfraktion)

The four mixtures described were then subjected to a distillative separation. The final temperatures were in the case of the stabilized samples of the distillation residue was in this case about 5% by mass of Einsatamenge at 410 ⁰ C.. The formation of solid products was not observed. In the case of the untreated samples, decomposition and separation processes occurred at 320 ° _C. The distillation residue at this temperature was SC hlB-%.

Claims (6)

invention claims 1. Process for processing brown coal tars, primarily of thermal! unstable coking und.Generatorteeren aus.Sauerstoffreichen lignite, characterized in · that the ¹ provided for eine.nachfolgende distillation and / or hydrogenated workup Braunkohlenteere at temperatures of 200 to 500 ⁰ C (preferably ЗОО to 400 ⁰ C) .and ' a process document. of less than 25 MPa with a CO / Dampfr bzw..C0 / H ₀ / steam mixture is used hydrogenating, wofce.i the supply of the 'hydrogenation already during the.-AufheiZperiode' or after reaching the Reaktionsbedinguncen · .. ?. The method according to item 1, characterized in., · That in _un Zuiühr g (3q HydriermitteiLS _S '"during the .Aufheizperiode, the average · Aufhelzge.schwindigkeit a maximum of 10 ° C / min" Method. na cn point: · 1 and 2., · Characterized in that the Aufheizre'gime from the outset with the distillative workup'urerburide & becomes, where'.die accumulating Einzelfraktidnen Bedarfswelse / im. Afterwards, they are to be further sterilized. 4. The method of item T. to 3, "characterized in .that the subsequent hydrogenating Spaltung.und / or conditioning means mqlekularean hydrogen or CO / steam or CO / H ^ / Dömpf-rGemisch at temperatures above 350 ⁰ C. - can be connected directly or after an intermediate distillative work-up. 5. The method according to item 1 to 4, characterized in that when used stau.bhaltig.er i'Teere or existing dust particles separated before workup, or can be included directly in the subsequent hydrogenation. 6. Method nach.Punkt.1 to 5 », characterized in that at appropriate point of the process d he ie. in addition to admixture of / carbon atomic carbon. 7. The method according to item 1 to 6, characterized in that the. Stabilization and subsequent hydrogenation and / or dehydration. Conditioning mitteis ^ molecular hydrogen or СО / steam or CO / ^ / Daräpfr mixtures carried out with or without Katalys.atorzusatz. 8. Procedure according to point. 1 to..., Characterized in that the use of the CO / Hp / Öaiapf-Gsmisches takes place in the form of Verga.sungs- .bzw * synthesis gas.