WO2009053234A1

WO2009053234A1 - Method and device for obtaining diesel or heating oil from residues containing hydrocarbons

Info

Publication number: WO2009053234A1
Application number: PCT/EP2008/063351
Authority: WO
Inventors: Esther Stölzer; Dawlet Hannoudi; Ullrich Fiedler
Original assignee: Hii Gmbh
Priority date: 2007-10-26
Filing date: 2008-10-06
Publication date: 2009-04-30
Also published as: DE102007051373B4; DE102007051373A1

Abstract

The invention relates to a method for obtaining diesel or heating oil from residues containing hydrocarbons is characterized in that the residues containing hydrocarbons are abruptly evaporated in a heating evaporator device without the presence of a catalyst. A device for performing the method comprises a pyrolysis reactor in the form of a screw feed system or a thin-layer evaporator and a rectification device.

Description

Process and apparatus for recovering diesel or fuel oil from carbonaceous residues

The present invention relates to a process for the production of diesel or fuel oil from hydrocarbonaceous residues and a device for this purpose.

State of the art

Catalytic processes for the conversion of hydrocarbon-containing residues for the production of diesel are known from the prior art, which are usually carried out at temperatures of 300 to 400 ⁰ C.

Thus, WO 2006/092306 A1 describes a process for the depolymerization of hydrocarbon-containing residues to diesel, wherein on the one hand a heated reactor in which the catalytic cracking of the raw material takes place is used and on the other hand the raw material is preheated and injected under pressure into the reactor.

However, stepwise heating of the raw material causes carbon to be deposited on walls of the apparatus used to perform the processes, for example by local overheating. This disturbs the heat transfer in the mixture and jeopardizes the safety of the process. The use of depolymerization catalysts is also expensive and requires further equipment to regenerate or exchange the catalyst. Continuous process control is therefore only possible with increased expenditure on equipment.

It is therefore desirable to provide a process for recovering diesel or fuel oil from hydrocarbonaceous residues and an apparatus for carrying out the process which do not have the disadvantages described. Task and solution

Consequently, it is an object of the present invention to provide a process for the production of diesel or fuel oil from hydrocarbon-containing residues and a device to do that do not have the disadvantages described.

This object is achieved in that the raw material is vaporized abruptly in a suitable evaporation device.

The raw material is not slowly heated, which would lead to the disadvantages described above, but within a very short time to a temperature in the range of about 150 ⁰ C to about 450 ⁰ C, preferably about 250 ⁰ C to about 400 ⁰ C heated, whereby the thermal decomposition of the hydrocarbon chains contained in the raw material occurs immediately. The process of the invention does not require a catalyst to crack the carbon water chains.

Advantageously, in the cleavage of long hydrocarbon chains thus carried out, an increased yield of shorter hydrocarbon chains, namely having a chain length in the range of about 10 to 25 carbon atoms, is observed.

The sudden evaporation of the raw material can be carried out, for example, in a thin-film evaporator and / or in a screw conveyor system which is operated or heated, for example, by a circulating fluidized-bed furnace.

The following describes some important process steps and parameters. raw material

Used as hydrocarbon-containing residues (raw material) for carrying out the process are, for example, waste, heavy and bilge oils, refinery residues and plastics or else oil-laden sands. In principle, waste, residual and waste materials come into consideration, such as plastics, oils, fats, natural and synthetic rubbers. Mixtures of all the aforementioned substances are also suitable as raw material for the process of the present invention. Particularly suitable are mixtures of waste oil and plastics.

preparation

The actual splitting of the raw material may be preceded by at least one desulfurization and / or dechlorination stage. By adding suitable additives to the raw material, desulfurization and / or dechlorination of the raw material can be accomplished.

Further, it may be necessary to thermally pretreat the raw materials to achieve, for example, better rheological properties. For example, waste oil can be preheated to about 120 ⁰ C before it is fed to the cleavage stage with higher temperatures. For plastics and plastic granules, it may be advantageous to subject them to a drying step.

Cleavage of the raw material

According to the invention, the cleavage of the raw material can be carried out in a thin-film evaporator or in a screw conveyor system which is operated or heated, for example, by a circulating fluidized-bed furnace.

Liquid raw materials such as waste, heavy and bilge oils, refinery residues and molten plastics are preferred using a Split thin film evaporator. The raw material contained in oil-laden sands is preferably cleaved using said screw conveyor system.

thin film evaporator

Thin-film evaporation is the thermal separation of substances from a mechanically generated, thin and highly turbulent liquid film. The liquid comes after entering the thin film evaporator with a rotor into contact: It is evenly distributed by a distribution ring on the circumference, detected by first, underlying rotor blades and as a film (eg 0.5 to 3.5 mm film thickness) to a distributed heated wall. Before each rotor blade, the liquid forms a bow wave. This is absorbed by the rotor blade and passes in the gap between the rotor and wall in a highly turbulent zone, in which it comes in the radial direction to intense heat and mass transfer. The high turbulence ensures high heat transfer rates even with viscous liquids. Due to the intensive product mixing in the bow wave, temperature-sensitive products are also protected against overheating and the formation of deposits on the heating surface is counteracted.

The introduction of the raw materials is carried out depending on the selected material flow on granulator or injector, each under the usual procedural pressure. In the thin-film evaporator, the input liquid raw materials are suddenly vaporized. The generated hydrocarbon vapors rise into a rectifier and can subsequently be treated in an optional stage with superheated steam to saturate free valencies.

Screw Conveyor System

Here, in a screw conveyor system to about 150 ⁰ C to 450 ⁰ C, preferably about 250 ⁰ C to about 400 ⁰ C heated fine-grained granules, such as sand or quartz sand, moves. The raw materials are se introduced by means of a gear pump directly into the granules or applied to the granules and cleaved immediately after the entry in or order on the heated granules. The residues (eg coke, metals and salts) are bound to the fine-grained granules.

The heating of the screw conveyor system succeeds, for example, with a circulating fluidized bed combustion coupled thereto. Preferably, a circulating fluidized bed combustion with combustion chamber, cyclone and fluidized bed lock can be used.

In the fluidized bed, the granules are heated in the circulation through cyclone and lock to the necessary temperature. During the start-up process, the system is operated with a gas burner to a temperature of max. 1400 ⁰ C driven; In stationary operation, part of the required energy is supplied by coke burnup. Basically, the fluidized bed combustion with a temperature of about 450 ⁰ C to about 1400 ⁰ C are operated.

The abovementioned residues are conveyed back into the fluidized bed with the fine-grained, non-vitrifying granules in the fluidized bed. There, the granules are cleaned at a maximum of about 1400 ⁰ C and recirculated.

The resulting exhaust air is cleaned and fed, for example, an exhaust chimney.

The fluidized bed therefore has on the one hand the task of heating the granules to the temperature necessary for the conversion and, on the other hand, of facilitating the regeneration of the granules contaminated during the conversion with residues.

The process of circulating fluidized bed combustion is characterized by uniform temperature control and high mass and heat transfer during operation of the plant. Optionally, the screw conveyor system (mixing screw) and / or the distillation column described below can be operated under reduced pressure.

Rectification and processing

For rectification, which serves for the separation of low boilers and cleavage gases, optionally their disposal in the fluidized bed and the condensation of the liquid product, for example, a distillation column with evaporator and condenser can be used.

By distillation and rectification is meant the physical separation of mixtures. The rectification or rectification apparatus vapor or liquid fed inlet mixtures are decomposed into their components or separated into partial mixtures.

In the context of the present invention, a rectification is carried out, for example, in column apparatuses with various internals and rectification plates, random packings and / or packings. There are no special requirements for the columns. For example, five column shots can be used.

After the rectification, the hydrocarbons obtained for binding of the free valences with superheated steam can, for example, at temperatures greater than about 1000 ⁰ C, are treated under pressure. This ensures that a clean and shelf-stable product is produced.

Finally, the product is cooled and is available for further use. Use of the products

The products obtained according to the invention can be used to generate electricity in corresponding power plants, as heating oil or as fuel for diesel engines.

Inventive method and apparatus

The method according to the invention can comprise the following steps:

A) Providing raw material with long-chain hydrocarbons;

B) optionally desulfurization and / or dechlorination of the raw material;

C) Cleavage of the raw material by flash evaporation in a temperature range of about 150 ⁰ C to about 450 ⁰ C, preferably in hydrocarbons having a carbon chain length of about 10 to about

25;

D) rectification of the cleavage products;

E) if appropriate, preparation of the cleavage products;

The cleavage of the raw material according to step C) of the process can be carried out by means of a thin-film evaporator or in a screw conveyor system operated by a circulating fluidized bed furnace. It is essential that no catalyst is used for cleavage.

A device according to the invention may comprise the following devices:

I) at least one pyrolysis reactor in the form of a

Ia) screw conveyor system with fluidized bed firing or Ib) thin-film evaporator; and II) at least one rectification device comprising, for example, a distillation column and an evaporator for the condenser, which are used to separate off low boilers and split gases and their disposal. tion in the fluidized bed and the condensation of the liquid product is used.

In addition, at least one waste heat boiler and / or at least one turbine and / or at least one superheater may be included in the device. Preferably, the superheater is present only if the pyrolysis reactor is designed as a screw conveyor system.

The rectification device is downstream of the pyrolysis reactor.

It is understood that other facilities may be present, such as conduits to interconnect the various facilities, pipes such as exhaust pipes, measuring and control equipment, stairs, stages, venting and ventilation ducts.

characters

The invention is explained in more detail by the attached figures, without being limited by them.

Show it:

1 shows the flowchart of a first method according to the invention, FIG. 2 shows the flow chart of a second method according to the invention, FIG. 3 shows a device according to the invention with fluidized bed,

4 shows a device according to the invention with a thin film evaporator in a vertical embodiment and FIG. 5 shows a device according to the invention with a thin film evaporator in a horizontal configuration. LIST OF REFERENCE NUMBERS

10 circulating fluidized bed

11 a Screw conveyor system (evaporator) 11 b Thin-film evaporator

11 c thin-film evaporator

12 column

13 head capacitor

14 sand return pipe 15 burners

16 activated carbon filters

17 dryers

18 buffer tanks

19 Preheater 20 Exhaust air tube made of fluidized bed

21 pipe to the exhaust chimney

30 pipe to the tank system

31 pipe from used oil tank

32 Plastic conveying belt 40 Pipe from preheater to desulphurisation device 41 Desulphurisation device

The process shown in Fig. 1 comprises a desulfurization step and a dechlorination step which reduce the sulfur and chlorine contents of the raw materials (plastics and waste oils) stored in respective storage facilities. The treated plastics are dried; The oils treated in this way are preheated to approx. 120 ^° C. The dried plastics and preheated waste oils are mixed and fed to a thin-film evaporator together with further dried plastic and / or preheated waste oil. The product mixture produced in the thin-film evaporator is treated with superheated steam, then rectified in a distillation column and finally cooled. To be obtained Diesel or heating oil, which comply with the DIN standard 51 601 and the Euro standard EN 590 for diesel and extra fuel oil.

The process shown in Fig. 2 comprises a desulfurization step and a dechlorination step, which reduce the sulfur and chlorine contents of the raw materials (plastics and anthers) stored in appropriate stores. The treated plastics are dried; The treated waste oils are preheated to approx. 120 ^° C. The dried plastic and preheated waste oil are mixed, and together with a soft terem dried plastic and / or pre-heated used oil a pyrolysis reactor (auger system) supplied to the at about 150 ⁰ C to about 450 ⁰ C, preferably about 250 ⁰ C to about 400 ⁰ C. is operated. The granulate for the screw conveyor system is heated and cleaned with a fluidized bed furnace. Before the granules enter the pyrolysis reactor, the granules are cooled to the desired temperature. The product mixture produced in the pyrolysis reactor is treated with superheated steam, then rectified in a distillation column and finally cooled. Diesel or heating oil, which comply with the DIN Norm 51 601 and the Euro Norm EN 590 for diesel and extra-light fuel oil, are obtained.

FIG. 3 shows a fluidized-bed installation according to the invention, for example for carrying out the method outlined in FIG. 2. Shown is a circulating fluidized bed 10, which is connected to a screw conveyor 11 a. Via a sand return pipe 14, the sand used is recirculated. A burner 15 ensures the heating of the sand. The screw conveyor system 11 a is continuously supplied via a pipe 31 waste oil. The products obtained by sudden evaporation of the waste oil in the screw conveyor 11 a products are fed to a column 12, in which they are rectified. In the downstream top condenser 13, the desired products are condensed, then cooled and fed via the pipe 30 to a storage tank. The system further comprises an activated carbon filter 16 for cleaning the exhaust air from the fluidized bed. The exhaust air is supplied to the activated carbon filter 16 via an exhaust pipe 20. The exiting the activated carbon filter 16 exhaust air is supplied via the pipe 21 an exhaust chimney.

Fig. 4 shows a system according to the invention with upright thin-film evaporator 11 b. The temperature required for the evaporation is generated by a burner 15. Via a buffer tank 18, fuel can be supplied to the burner 15, which consists of volatile, combustible constituents of the vaporized plastic and the distillate produced (corresponding supply lines are not shown). The thin-film evaporator 11 b is supplied by means of fluid bed dryer 17 dried plastic. A plastic conveyor belt 32 delivers the plastic to the dryer. The products obtained by sudden evaporation of the plastic in the thin film evaporator 11 b are fed to a column 12, in which they are rectified. In the downstream top condenser 13, the desired products are condensed, then cooled and fed via the tube 30 to a storage tank. Shown is a column with two outlets, where up to seven outlets are possible. The system further comprises an activated carbon filter 16 for cleaning the exhaust air produced in the process.

Fig. 5 shows a system according to the invention with horizontal thin-film evaporator 11c. The temperature required for the evaporation is generated by a burner 15. The thin-film evaporator 11 c desulfurized by means of desulfurization 41 and supplied preheated by preheater 19 waste oil. Shown in this context are ds pipe 40, which connects the preheater 19 with the desulfurizer 41 and pipe 31 from the waste oil tank in the preheater 19. The products obtained by sudden evaporation of waste oil in the thin film evaporator 11 c products are fed to a column 12 in which they rectified become. In the downstream top condenser 13, the desired products are condensed, then cooled and fed via the pipe 30 to a storage tank. Shown is a column with two outlets, where up to seven outlets are possible. The system further comprises an activated carbon filter 16 for cleaning the exhaust air produced in the process. Shown is also an exhaust pipe 21 to a fireplace. Not shown are feed lines to supply volatile, combustible components from the distillate produced in the column 12 and the preheater 19 to the burner 15.

The invention is explained in more detail by the following example:

example

2.5 kg of high-molecular-weight hydrocarbons, which had remained as residue in the petroleum fractionation, served as starting material for the production of diesel or heating oil.

The high molecular weight material having a solid consistency at room temperature, was first pre-heated to 120 ⁰ C, and thus converted into a pumpable state. In this state, the material was metered in portions under atmospheric pressure in a thin-film evaporator whose wall was heated to a temperature of about 400 ⁰ C. On the hot wall of the high molecular weight hydrocarbon was distributed by a fast-running agitator to about 2 to 3 mm thick layer, which immediately began a sudden evaporation.

The resulting hydrocarbon vapors were then condensed and then fed to a multistage distillation column equipped with a bottom vaporizer and a top condenser. The obtained middle distillate oil was then treated at a pressure of up to 2 atmospheres with superheated steam, the inlet temperature was maintained 1000-1100 ⁰ C. This resulted in storable products.

A total of 1,160 g of primary hydrocarbon vapors were condensed. The multi-stage distillation yielded 110 g of light oil distillate and 926 g of middle oil distillate. This left 124 g as a residue in the bottom of the distillation column. The middle oil distillate complied with European standard EN 590 for diesel fuel.

Claims

claims

1. A process for the production of diesel or fuel oil from hydrocarbon-containing residues, characterized in that the hydrocarbon-containing residues are abruptly evaporated in a heated evaporator device without the presence of a catalyst.

2. The method according to claim 1, characterized in that the heated evaporator device is a thin-film evaporator or a, preferably by a circulating fluidized bed furnace operated or heated, screw conveyor system.

3. The method according to any one of the preceding claims, characterized in that the evaporation in a temperature range of about

150 ⁰ C to about 450 ⁰ C takes place.

4. The method according to any one of the preceding claims, characterized in that the evaporation takes place in a temperature range of about 250 ⁰ C to about 400 ⁰ C.

5. The method according to any one of claims 2 to 4, characterized in that the screw conveyor system comprises a heated fine-grained granules, on and / or in which the hydrocarbon-containing residues on and / or introduced.

6. method vorangehendem claim, characterized in that the fine-grained granules are sand or quartz sand.

7. The method according to any one of the preceding claims, characterized in that as hydrocarbonaceous residues Alt-, heavy and bilge oils, refinery residues, plastics, oil-laden sands, Alt-, Residues and waste, fats, natural and synthetic rubbers and mixtures of all the above can be used.

8. The method according to any one of the preceding claims, characterized in that as hydrocarbon residues from mixtures

Used oils and plastics.

9. The method according to any one of the preceding claims, characterized by the following steps, preferably in the order given:

A) Providing raw material with long-chain hydrocarbons;

B) optionally desulfurization and / or dechlorination of the raw material; C) cleavage of the raw material by sudden evaporation;

D) rectification of the cleavage material;

E) if appropriate, preparation of the cleavage products.

10. The method according to the preceding claim, characterized in that the rectification in a distillation column with evaporator and

Capacitor is performed.

11. The method according to any one of claims 9 or 10, characterized in that step E) comprises the treatment with superheated steam and / or cooling.

12. A device for the production of diesel or fuel oil from hydrocarbon-containing residues without the presence of a catalyst, in particular for carrying out a method according to one of the preceding claims, comprising the following devices:

I) at least one pyrolysis reactor in the form of a Ia) screw conveyor system, preferably with fluidized bed furnace or Ib) thin-film evaporator; such as

II) at least one rectification device.

13. Device according to the preceding claim, characterized in that the rectification device comprises a distillation column and an evaporator.

14. Device according to one of claims 12 or 13, characterized in that it additionally comprises at least one waste heat boiler and / or at least one turbine and / or at least one superheater.