CS251530B1 - A process for treating heavy pyrolysis oils and resins - Google Patents

Abstract

The purpose of the modification is to improve further processing of pyrolysis raw materials. The repair is carried out by converting the 'Treated - purified substance into a solution in hydrogenated oil, or washing oil, or in their mixture, followed by removal of the predominant part of the content of insoluble solid components in a sedimentation centrifuge. The solvent used is finally removed by distillation. Refined pyrolysis oils and resins are suitable for processing into demanding carbon products, such as needle coke, carbon fibers, etc.

Description

251530

It is an object of the present invention to treat heavy pyrolysis oils and veins by reducing the content of their insoluble components in order to improve their processability. The preparation of solutions of heavy pyrolysis prodrugs and removal of insoluble constituents represents an intermediate stage of their technical processing, to more valuable products. Heavy pyrolysis oils and resins are the byproducts of crude oil processing and its share. Acetylates are obtained after separation of the more valuable pyrolysis products in a series of multiple separation processes. The impurities of the starting raw materials pass into their composition, the other impurities of the pyrolysis processes and the pollutants of their secondary realizations being formed by distillation separation at high temperatures. In distillation, these constituents concentrate and determine the properties of the distillation residues and the possibility of their processing. Heavy pyrolysis products, with regard to their composition and properties which are mostly inefficient, eg as fuels, additives or asphalt substitutes, or are processed into barbecue materials of carbonaceous material, or are not utilized at all and accumulate in environmentally hazardous areas. kách. Only a small, selected portion of the pyrolysis products is processed into technically expensive types of carbon products such as carbon coke, carbon fibers, and the like. Important undesirable components of heavy pyrolysis products are solid, i.e., insoluble and non-fusible, materials dispersed in a large particle size. These are mainly formed by popotovin, fine-grained cocci, half-coke and others.

The demands of more sophisticated low-solids production in pyrolysis products still address the prevailing selection of suitable pyrolysis oil, or bitumen, with or without a low content of solids, which does not interfere with processing, or can simply be reduced to a load bearing capacity.

This approach greatly limits the possibility of using various pyrolysis materials efficiently. On the other hand, such limited winnings do not create the preconditions of providing a sufficient amount of raw material for demanding carbon products, which the development and increased need for technical development necessitate.

The solution to the problem of ensuring the need for heavy pyrolysis raw materials of satisfactory quality is to find a suitable treatment, i.e. suitable separation methods and conditions for the removal of undesirable impurities and pastes which have been used extensively so far. In principle, it can be filtration, sedimentation and extraction. The application of these methods to a number of technical obstacles resulting from the properties divided by the articles such as the viscosity of the pyrolysis raw materials, the size and the particle size of the solids, and the like.

The solution to the problem of removing solid constituents is to purify the pyrolysis oils, resin solutions.

A key issue in the solution of the proposed separations is then to find suitable technical solvents and the preparation of manageable solutions of heavy pyrolysis prodrugs, since other so far sizing separations from tavern resins at elevated temperatures have only a very limited effect and convertibility and are cited in connection with by filtering such pyrolysis resins, which themselves have low sub-solids.

Many of the better preconditions for the use of the separation poles form when converting the pyrolysis resins into solutions. In a quasi-manner, it is possible to reduce the viscosity, viscosity and density of the handled materials and thus extend the range of usable raw materials to pyrolysis products with a higher solids content.

A prerequisite for the solution is the wins of suitable solvents providing solutions of pyrolysis resins having relatively favorable properties for the application of an efficient paraffin process.

However, in the selection of solvents and the development of the process for removing solids from pyruvous raw materials, several technical problems have to be taken into account, which result from the properties of the substances and their systems, in particular from their limited solubility, viscosity properties of the melt and small particle size solutions separated solids, etc.

It has been found that several active solvents or mixtures thereof with a relatively low density and viscosity, limited volatility in the possibility of their removal and regeneration by distillation have been used in preparing solutions. In addition, the solvent used should not be toxic and corrosive and be hungry.

Individually the solvents or their corresponding requirements for prepyrolysis products have found application in the analytical characterization of their group composition and in the preparative selective separation of individual fractions. When separating solids from the ground, the use of solvents is mentioned only in connection with the possibility of filtration. However, it appears that anifiltration or conventional extratocation processes cannot be applied technologically with pyrolysis resins with a higher solids content.

The use of pure solvents or defined mixtures thereof in the preparation of solutions is advantageous in that substances with defined properties are handled. When reusing solvents to prepare solutions of pyrolysis products and recovering them by distillation, this advantage is lost, over the rain, and transferred to the solvent-volatile component of the dissolved -a

Even with 6 251530. In the case of regeneration, the content of the solvents in the solvents is gradually increased. In this case, it is more advantageous to use a mixed solvent which already contains components identical to the light volatilization of the purified pyrolysis product and to maintain the content of these components at a stable level during regeneration.

In addition to the aforementioned advantage of the solvent with the aforementioned properties, the lower cost than the pure solvent may be substantial.

It has been found experimentally that by observing the aforementioned principles in the solvent selection, respecting the limitations corresponding to the nature of the purified pyrolysis product and the solids content thereof, a resin solution free of the predominant component and a resin having a residual solids content can be distilled off. 1%.

It has been shown that the treatment of heavy ipyrolysis oils and resins and the reduction of their insoluble constituents can be accomplished by dissolving the heavy pyrolysis oil and resins in 1 to 10 moles of hydrated oil or washing oil or mixtures thereof the solution is freed from the predominantly insoluble fraction by sedimentation in the centrifuge, and then the solvent is removed by distillation. The hydrogenated oil is a technical solvent obtained by the torsalization treatment of the distillation residue after distillation of the hydrogenated refined coke benzene. Washing oil is a fraction of stone oil distilling between 230 and 300 ° C.

The use of hydrogenated oil, or an oil thereof, or a mixture thereof of an alcohol solvent of pyrolysis oils, resins or a fraction of coal tar to prepare solutions for the centrifugation of sedimentation solids has more advantages. for the predominant proportion of heavy pyrolysis with pure solvents. In doing so, they slightly support the aggregation of the debris removed and thus facilitate its settling. The low vapor pressure and relatively high vapor pressure are advantageous for maintaining the fire hazard, at an acceptable level.

On the other hand, they allow the distillate removal of the solvent after removal of the solids. The regeneration of the distilled solvent for proper use is easily ensured by the partial freeze-drying, so as to maintain its approximate composition upon repeated use. In addition to the abovementioned technical and mixed solvents, they are more preferred as individual solvents. Of the different separation methods, sedimentation centrifugation is advantageous when removing solid components from pyrolysis products. Filtration or centrifugation results in a favorable result for the rapid formation of a practically insoluble cake. Extraction is associated with the release of solid particles into the extraction solutions, i.e. the problem of extraction is essentially consistent with filtration problems.

The amount of solvent compared to the amount of purified pyrolysis material must meet the requirements of low viscosity and density, low or low temperature centrifugation, with sufficient separation effect, and the need to control the solvent removal by distillation without adversely affecting the resistivity of the resins. Furthermore, with the desirable diluent effect of the solvent, there is a contradictory need to minimize the amount of solvent, and, after separation of the solids from the resin, the volume capacities of the distillation plants must be removed with minimal energy demand and favorable technological utilization. The preparation of solutions of pyrolysis products and removal of their insoluble constituents of the present invention are illustrated by the following examples: EXAMPLE 1 100 g of heavy pyrolysis oil were dissolved in 300 ml of hydrogenated oil. 50 ml of the prepared solution was added to the centrifuge tubes. After a half hour of centrifugation at 3000 rpm, a substantial part of the solids from the centrifuged solution settled on the bottom of the cells. The remainder of the particles was dispersed in a movable layer in which their icono-titration decreased to the surface. The solvent layer just below the surface was clear. The topcoat was recovered to give a 50-60% solution of the light-to-trace solution. Purified pyrolysis oil is regenerated by distilling off the solvent. Example 2

The procedure was similar to that of Example 1 except that the starting solution was prepared by dissolving 200 g of heavy pyrolysis oil in 200 zeros of hydrogenated oil. In this case, the centrifuged solution needed to be preheated proved to be necessary. The initial temperature was 60 ° C. P r i lk 1 ad 3

The procedure was similar to that of Example 1. However, a dilute solution of heavy pyrolysis oil was used in a ten-fold amount of solvent. The solids were settled efficiently. However, a large amount of solvent had to be distilled off during recovery. Example 4> 20 kg of heavy pyrolysis oil with a content of 2.47% solids dissolved in

Claims (1)

2515 7 80 1 hydrogenated oil. The solution was centrifuged at 8,000 rpm and at a flow rate of 0.8 l of minus. The solvent and volatile constituents of the starting material were distilled from the centrifuged solutions. The resulting distillation residue of about 10 kg contained 0.9% solids. EXAMPLE 5 Similar to Example 4, except that a solution of 20 kilograms of heavy pyrolysis oil was prepared in 40 liters of hydrogenated oil, and the other results were similar to Example 4. 30 8 Example 6 1, with the difference that instead of hydrogenated oil, washing was used. The results were compared to Example 1. Example 7 The procedure was similar to Example 4 except that washing oil was used instead of the hydrogenated oil. The results are similar to Example 4. EXAMPLE 8 The procedure was similar to Example 4. However, a mixture of 40 L of hydrogenated oil and 40 L of wash oil was used in place of the hydrogenated oil. P RE DMET Treatment of heavy pyrolysis oils and resins by reducing their insoluble matter, characterized in that the heavy ipylolysis oil or resin is dissolved in 1-10% of hydrogenated oil or washed oil, or mixtures thereof and prepared The solution is freed from the predominant part of the insoluble fraction by centrifugation in a sedimentation centrifuge and then dissolved by distillation. Savarograíla, n. P., Závod 7, Most Price 2,40 Kčs