EP1745115B1 - Device and method for recovering fractional hydrocarbons from recycled plastic fractions and/or from oily residues - Google Patents

Abstract

The invention relates to a method for recovering fractional hydrocarbons from recycled plastic fractions, which are sorted according to type and compacted under the exclusion of air using a feed system (1, 2, 3, 4), the compacted mass being supplied to a fusion container (7), where it is heated. The mass is separated into a first liquid phase, a first gas phase and a residual fraction, the liquid phase and the first gas phase are then transported to an evaporation container (20), in which a second liquid phase and a second gas phase are produced by the application of heat. The second liquid phase is transferred to a secondary heater (23) and heated further to produce a third gas phase. The second gas phase and the third gas phase are then supplied to a cracking tower (27), in which further cracking of the long-chained hydrocarbons occurs and short-chained hydrocarbons are produced. The oil gas is supplied to a primary condenser (30), in which it is condensed to liquid oil, the latter constituting the target product.

Description

Technical area:

The invention relates to a method for obtaining fractionated hydrocarbons from plastic materials and / or from oil-containing residues, wherein the plastic materials and / or residues sorted by variety and compacted using a registration system and the compacted mass to a melting vessel, preferably below the liquid level, fed and is heated so that a separation into a first liquid phase, a first gas phase and a residue portion takes place, according to the preamble of claim 1; Likewise, the invention relates to an apparatus for performing the method according to the preamble of claim 16 for obtaining fractionated hydrocarbons from plastic materials and / or from oil-containing residues.

State of the art:

Today, plastics are used in almost all areas of life and must be recycled and / or disposed of after use. At the same time, health-friendly disposal poses considerable problems. Plastics such as polypropylene (PP), polyethylene (PE) or polystyrene, which consist of long-chain macromolecules, must be split into small molecules for their utilization. Through a conversion plant, such plastics can be converted in a low-temperature cracking process into an oil-like product with gaseous admixtures and a solid residue.

The resulting gas during the cracking process consists of a mixture of methane, ethane, ethene, propane, propylene, i-butene, i-butane, 1-butene, 1-butane, pentane, etc., and a small amount of water vapor. The polystyrene-derived oil consists of more than 50% styrenes and also contains 2-methyl-styrenes, toluene, ethylbenzene and benzene. The oil obtained from polyethylene and polypropylene consists mainly of paraffins and olefins and contains only small amounts of aromatics. The low-volatile residues consist of cokes, heavy oil-like long-chain hydrocarbons. The oil-like residue can in a further process step be mixed with water. This produces an oil-water emulsion, which can be utilized energetically, for example as a lighting agent.

By the JP-A-08-034978 has become known a method and an apparatus for the production of low-boiling hydrocarbons from plastics. For this purpose, the device has a first heatable melting container to which the plastics are fed via a feed screw and in which the melting of the plastics results in a first liquid phase which can be fed to a further second container to which a cracking tower for oil extraction is connected. From the second container, the liquid phase is traceable back into the heatable first melt container in a circulation process for further heating.

By the CN-A-1284537 a method for recovering hydrocarbons, such as gases or oils, has become known from plastic materials, which has a melting and cracking process with subsequent oil gas separation and distillation of the oil mixture. For this purpose, plastic raw materials for melting and vaporization are brought within a container (melting and cracking reactor), which are supplied to the container via a feed screw. The plastic raw materials are heated to 280 ° C to 380 ° C and cracked. The disadvantage here is the single-stage entry of the necessary heat energy. The high heat flow density leads to strong partial overheating. These then lead to the formation of encrustations, which worsen the further heat input. As a result, the heat consumption is high in relation to the yield. By the CN 2435146Y Furthermore, a similar method has become known.

By the US-A-4,584,421 For example, a method and apparatus has become known which can be thermally decomposed by the same plastic waste to recover liquid hydrocarbon oil as a finished consumable or crude oil. For this purpose, the device has a heatable with a burner first reaction vessel, which is preceded by a receptacle from which by means of a screw conveyor, the plastic waste together with a Catalyst in the reaction vessel to be promoted to melting. The gaseous, distilled product is conveyed to a second heated reaction vessel which has a catalyst bed of catalyst particles of size between 1 mm to 15 mm in diameter, namely calcined zeolite particles about 10 mm in diameter, whereby the gas is catalytically decomposed. The catalyst material which has been added to the plastic waste is recovered from the first reaction vessel and heated above 500 ° C, after which the catalyst material can be reused.

Technical task:

The invention has for its object to further develop the aforementioned method and apparatus that the energy input is improved and that in particular by an optimal and targeted use of energy and heat recovery in different areas of the efficiency of the method and the device is improved.

Disclosure of the invention and its advantages:

This object is achieved in that the liquid phase and the first gas phase are transported to an evaporation tank in which further heat input, a second liquid phase and a second gas phase is formed, wherein the second liquid phase is transferred to a reheater and further heated there with further heat input so that a third gas phase is formed, after which the second gas phase from the evaporation vessel and third gas phase from the reheater are fed to a cracking tower, where further cracking of the long-chain hydrocarbons into short-chain hydrocarbons takes place and the resulting oil gas is then fed to a condenser, in which the oil gas is condensed to liquid oil, where the oil is the target product, and the process is carried out using a multi-circuit heating system to generate the necessary process heat for the melting tank, the evaporation tank and the reheater, and used as a heat transfer oil or salt or gas.

In a further embodiment of the method according to the invention, this is carried out using a multi-circuit, indirect heating system which generates the process heat for the melting tank, the evaporation tank and the reheater, it being possible to use oil or salt or gas as the heat carrier. For this purpose, a non-condensable fraction of the oil gas for thermal utilization can be supplied to the heating system for firing the same in an advantageous manner. The heating system thus comprises all components for the supply of the melting vessel and the evaporation vessel with energy. The thermally recoverable by-products formed in the process, such as a proportion of an oil-water emulsion from the residue components from the Aufschmerzbehälter and otherwise unusable gas fractions from the Crackturm and a gas component from a flame arrester, are used in an advantageous manner in the heating system for generating the primary process heat.

In addition, a maximum of heat from the area of the oil gas and residue precooling from a cooling system is advantageously returned to the heating system. For this purpose, the capacitor may consist of a precondensator and a main capacitor, which may be connected to a multi-circuit cooling system. The excess heat from the pre-condenser, the main condenser and the residual pre-cooling tank is thus fed to the heating system. Likewise, the oil-water emulsion for thermal utilization can be supplied to the heating system for firing.

The inventive method advantageously has a low energy consumption and optimum energy utilization by means of heat recovery, based on the yield. In particular, the heating circuit in the different process areas advantageously heats indirectly and specifically. In particular, by means of the method according to the invention, plastic materials can be recycled in accordance with the waste incineration regulations.

In a further embodiment according to the invention, a precondensator and a main capacitor are used as the capacitor, the excess heat from the precondensator, the main capacitor and a residual precooling vessel being supplied to the heating system, and the main capacitor being connected to a multi-circuit condensation system.

In a further embodiment according to the invention, the plastic materials and / or oily residues are comminuted in a pretreatment process after sorting and optionally dried before the cracking process is carried out. The plastic materials are sorted by PP, PE and PS into hard and soft plastic parts. Since the water content of the plastics should be below 1% for energy reasons, plastics with a higher water content are dried beforehand. To enter the plastic materials and / or the oil-containing residues in the melting container can be used within the registration system, a plug screw or a Stopfwerk, which compacts the residues for oxygen deprivation. Likewise, the plastic materials should be fed fine shredded the stuffing screw or Stopfwerk.

In a further embodiment of the invention, the residue is transported within the Aufschmelzbehälters in an underlying sedimentation where concentration of the residue is carried out and then the concentrated residue fraction is transferred to a residue precooler, in which a cooling of the residue fraction by means of a cooling medium, preferably below 120 The cooled residue fraction can be fed to an emulsion unit in which an oil-water emulsion is prepared from the residue fraction.

In a further embodiment of the method, a precondensator is arranged between the cracking tower and the main condenser, which pre-cools the oil gas and recovers heat at a high temperature level and reduces the temperature gradient between cracking tower and main condenser. Of Furthermore, the main capacitor and optionally the precondensator can be connected to a multi-circuit cooling system.

The inventive method is preferably carried out between 300 to 450 degrees Celsius and normal pressure up to 2 bar overpressure.

A device according to the invention for recovering fractionated hydrocarbons from plastic materials and / or from oil-containing residues, wherein the plastic materials and / or residues are sorted by variety, with a registration system for the compression of the plastic materials and / or oily residues under exclusion of air and with a downstream reflow tank for heating and melting the compacted mass to produce a first liquid phase, a first gas phase and a residue portion, is characterized in that after the melting vessel for generating further heat input of a second liquid phase and a second gas phase, an evaporation vessel is arranged, on which the introduction and Further heating of the second liquid phase, a reheater follows to the emergence of a third gas phase, and to the evaporation vessel and the reheater for breaking (cracking) of the long-chain Hydrocarbons in short-chain hydrocarbons, a cracking tower is connected to which a condenser is connected to the condensation of the oil gas to liquid oil as the target product, the apparatus having a multi-circuit heating system for generating the necessary process heat for the melting tank, the evaporation tank and the reheater optimized for this purpose Temperature levels, with oil or salt or gas as the heat carrier.

In a further embodiment of the device, a stuffing screw or a Stopfwerk for compressing the plastic material and / or the oil-containing residues is arranged for entering the plastic materials and / or oily residues in the melting within the registration system, before which optionally a spherical transfer container for transfer into the Plug screw or the stuffing mechanism is located. The output of the plug screw or the Stopfwerks opens below the liquid level of the molten mass in the Aufschmelzbehälter.

In a further embodiment of the device, the same has a multi-circuit heating system for generating the necessary process heat at this optimized temperature levels, serving as a heat carrier oil or salt or gas.

In a further embodiment of the device, a sedimentation compartment for receiving the residue part is arranged below the melting tank. To the sedimentation compartment can be arranged a residue precooling container as well as an emulsion unit for producing an oil-water emulsion from the residue portion.

In a further embodiment of the device, the capacitor is formed of a main capacitor and a precondensator, wherein between the cracking tower and the main capacitor for precooling of the oil gas, the precondensator is arranged. Furthermore, a multi-circuit cooling system can be connected to the main capacitor.

In a further embodiment, the device for generating the process heat for the melting tank, the evaporation tank and the reheater on a multi-circuit heating system.

Furthermore, the melting tank and the evaporation tank and, if appropriate, the after-heating tank have an externally arranged heating jacket and / or internal heating coils which can be heated via the common heat carrier heating system.

Figuren 1a, 1b und 1c

eine Prozessanlage über drei Figuren verteilt, zum Gewin- nen von fraktionierten Kohlenwasserstoffen aus Kunststoffrohmate- rial und/oder ölhaltigem Rückstände

Figur 2

ein modifiziertes Eintragungssystem gegenüber demjenigen der Figur 1

Figur 3

eine den Figuren 1a, 1B und 1c ähnliche Prozessanlage, in welcher die Wärmeträger- und Kühlkreisläufe genauer dargestellt sind

Figur 4

ein weiteres Eintragungssystem einer Prozessanlage

Figur 5

ein weiteres Eintragungssystem einer Prozessanlage mit einem Kühlmantel um das Zuleitungsrohr und Stopfschneckenmantel vor einem weiteren Aufschmelzbehälter

Figur 6

ein weiteres Beispiel eines Hauptkondensators und

Figur 7

eine weitere, der Figur 3 ähnliche Prozessanlage.

Short name of the drawing, in which show:

Figures 1a, 1b and 1c

distributed a process plant over three figures, to win of fractionated hydrocarbons from plastic raw material and / or oily residues

FIG. 2

a modified registration system over that of FIG. 1

FIG. 3

a the FIGS. 1a . 1B and 1c similar process plant, in which the heat transfer and cooling circuits are shown in more detail

FIG. 4

another registration system of a process plant

FIG. 5

Another registration system of a process plant with a cooling jacket around the supply pipe and plug screw shell in front of another melting tank

FIG. 6

another example of a main capacitor and

FIG. 7

another, the FIG. 3 similar process plant.

Preferred embodiment of the invention:

The process plant shown in the figures for obtaining fractionated hydrocarbons, from plastic materials and / or oily residues consists of a silo 1, in which the processed plastic materials, preferably in shredded state, are stored. The storage can also be done in a bunker. To remove the plastic materials is a marked by the letter "M" motor-driven trough screw conveyor 2 connected to the silo 1, which promotes a transfer container 3, for example, a flanged ball housing for flexible adaptation to different local conditions. At the transfer container 3, a stuffing screw 4 or a Stopfwerk connects, which compresses the plastic materials and thus largely expels the air and thus the oxygen. The lower end of the plug screw 4 or Stopfwerks opens into a melting tank 7 and that below or above its level. Between the end of the screw conveyor 4 or the Stopfwerks and the confluence with the Aufschmelzbehälter 7 a pneumatically operated throttle-check valve 5 is arranged, which is followed by an entry fitting 6 in the form of a ball valve 6.

The reflow vessel 7 has at its lower end a sedimentation tray 10 for receiving and concentrating a residue fraction precipitating from the liquid phase of the compacted mass. The sedimentation compartment 10 is conductively connected via three successive residue discharge fittings 11, 12 and 13 to a residue precooling vessel 15, which has an outer cooling jacket 14. Within the residue Vorkühlbehälters 15 an accumulation of the residue and a cooling of the residue by means of a cooling medium from a cooling system 34, preferably below 120 ° C. The pre-cooling of the residue takes place under the possibility of heat recovery in the heating system, thereby reducing the temperature gradient between Melting tank 7 and a subsequent emulsion unit 16 is given.

The cooled residue is fed to the emulsion unit 16 in which an oil-water emulsion is produced by means of a motor-driven agitator from the residue fraction. By reducing the temperature gradient also reduces the necessary water mask in the emulsion unit 16, whereby a higher oil concentration in the oil-water emulsion is possible and thus the calorific value of the same is raised.

The reflow vessel 7 has an agitator 9 for homogenizing the molten plastic mass and a Abrakeleinrichtung 17 for stripping the inner wall of the reflow vessel 7 in the region of the mouth of the screw conveyor 4 or Stopfwerks. Furthermore, the melting tank 7 is closed at the top and has a lateral outlet A in the upper area. This provides great strength in the area of the upper tank bottom by reducing the number of openings. Furthermore, the melting tank 7 is surrounded by an outer heating jacket 8, which is constructed such that a homogeneous heat input is given and in particular heat peaks are avoided during operation. Likewise, the outer heating jacket 8 allows heat removal, condensation, before maintenance or even in case of an accident.

Furthermore, the melting tank 7 and the evaporation tank 20 may be equipped with hinged concentric coiled tubing, for example two. By using coiled tubing for heat transfer, a larger transfer area is achieved.

Within the reflow tank 7 there is a heating of the plastic mass, so that a separation into a first liquid phase, a first gas phase and a residue portion takes place, after which the liquid phase and the first gas phase are transported via the outlet A line in an evaporation vessel 20, in which among others Heat input into the mass creates a second liquid phase and a second gas phase. The evaporation vessel 20 is used for evaporation of valuable parts with higher evaporation temperatures. The outlet A of the melting tank 7 and the inlet A of the evaporation tank 20 may have an additional heater 18, such as electric immersion heater, to which a further reheater 19 can connect to increase the heat input in the inlet of the evaporation tank 20.

The heat input into the evaporation tank 20 is controlled by a heating jacket 21 and / or heating coils at a higher level than in the melting tank 7 in a reduced amount of plastic, whereby a reduction in the amount of energy is given at a high temperature level. Also, the evaporation vessel 20 has a motor-driven agitator 22 for homogenizing the molten recyclable material. Within the evaporation vessel 20, the formation of a second liquid phase and a second gas phase takes place.

Parallel to the evaporation tank 20 a Nachheizbehälter 23 is connected by line, which has its own heater 24, which may be an electric heater E. The Nachheizbehälter 23 is used for further reheating and vaporizing an even smaller amount of recyclables than in the evaporation vessel 20 with the highest evaporation temperatures of the recyclables, so that in him a third gas phase is formed. The evaporation tank 20 is down by means of a residue discharge fitting 25, for example of the type ball valve, closed to discharge residues. The Nachheizbehälter 23 has in turn at its lower end an emptying valve 26 for emptying the Nachheizbehälters 23.

On the evaporation vessel 20, a cracking tower 27 is placed, which serves to break up the long-chain molecules into short-chain molecules; in Crackturm 27 there is a separation of the resulting oil gas from high-boiling components. Also, the Nachheizbehälter 23 is connected in line with the cracking tower 27, so that in the same both the second gas phase from the evaporation tank 20 and the third gas phase is introduced from the Nachheizbehälter 23. Via a product gas line 28, namely a pipe 28, the discharge of the product gas formed in the cracking tower in a pre-condenser 29 can be carried out, which works as a heat exchanger to recover heat at a high temperature level, so that this pre-cooling of the product gas with the possibility of heat recovery in the Heating system is done. The oil gas is then supplied to the main condenser 30, in which the oil gas is condensed to liquid oil.

The main condenser 30 has two cooling circuits, namely a sump cooling condenser 31 and a head cooling condenser 32. The main condenser 30 has an incoming and outgoing line with a circulating pump 35 for circulating the oil. Also located in the line are two automatic valves with a throttle function for switching and dividing the recirculation flow to the main condenser 30 or into a transfer line 37 to a separator (not shown). The conduit further has a metering point 40 as an injection site for delivery of additives, for example, to condition, stabilize and adjust product properties of the product oil.

Addition of an additive can also be made in the line between cracking tower and main condenser.

Furthermore, the main condenser 30 is conductively connected via a residual gas outlet 39 to a heating system 38 of the process plant, via the residual gas outlet 39, a derivation of the non-condensable portion of the product gas in the heating system 38 of the process plant for thermal utilization in the heating system.

The main condenser achieves a very rapid cooling and condensation of the hot product gas (shock cooling) to an average temperature level of 80-200 ° C by applying the process principle quenching.

The quench medium used is cooled condensate (product oil). The quenching can be done in two different ways: The hot gas stream is sucked into the liquid recycle stream of cooled condensate, where due to the high turbulence intensive heat exchange and immediate condensation of the product gas occurs. Or alternatively, the quench can be carried out as a packed column, wherein a liquid recycle stream of cooled condensate is trickled over the packing and hot product gas flows in countercurrent from bottom to top and thereby condenses. Due to the large surface of the packing, an intensive heat exchange between cold condensate and hot product gas is achieved, so that the latter condenses immediately.

Thus, by arranging two packed columns, the one can be regenerated while the other is operating normally, with the regeneration of the recycle stream in the packed column to be regenerated being shut off and the hot gas stream coming from the cracking tower being passed through the packed column to be regenerated, thereby causing the bed to fill is heated and deposits are replaced. The regeneration of the packed columns thus happens alternately.

In a further modification of the invention, the heat exchangers of the main capacitor do not necessarily have to be inside the condenser, for example be arranged as bottom and head cooling, but it is sufficient a heat exchanger in the line of the circulating flow.

The heating system is preferably multi-circuit for generating the necessary process heat at this optimized temperature levels. As a heat carrier oil or salt or gas can be used for heat transfer with adjustable maximum heating temperature. The efficiency of the heating system is thereby maximized by providing heat recovery to the system using the residual gas to fire the heating system. Thus, the method according to the invention does not require the separate gas combustion, gas flare, required in the prior art. The maximum energy utilization is also given because flexible heating of the heating system is possible by means of several optimized temperature levels, namely by the product oil, by the product gas and by the oil-water emulsion, as well as electrically or by a combination of the various aforementioned energy sources. In order to record and monitor the amounts of energy, the resulting temperature differences, the different pressures as well as the different flow rates of the heat transfer medium circuits can be used.

The FIG. 2 shows a modified registration system over that of FIG. 1 , The connecting tube of the melting container 7 for connecting the screw conveyor 4 or Stopfwerks is here formed at an acute angle to the melting vessel; otherwise the design is the same.

The FIG. 3 shows a process plant, which of those of FIGS. 1a . 1B and 1c is very similar and in which the heat transfer and cooling circuits are fully illustrated. The heating system 38 is divided into five heat carrier circuits WT 1 to WT 5. WT 1 is connected via lines to the melting tank 7 and supplies it with heat energy; Similarly, WT2 is connected to the evaporation vessel 20. WT 3 or WT 4 or WT 5 is connected to the heat removal with the precondensator 29 or with the cooling system 34 or with the residue precooling container 15.

The FIGS. 4 and 5 show two more examples of different registration systems of a process plant according to the invention. The reflow containers 39 shown here have an upper filler neck 40, through which a feed tube 41 is guided, whose opening is below the liquid level 42 of the liquid melt. In the FIG. 5 are the feed tube 41 and the screw plug additionally surrounded by a cooling jacket 43, which is traversed by cooling water.

The FIG. 6 shows another example of a main capacitor 44 of the process plant according to the invention. The hot gas enters through the opening 45 in the main condenser 44 and flows through packed columns 46, in which there are Füllkörperschüttungen, such as rings made of stainless steel. Liquefied condensate is withdrawn from the sump 54 via a line 47 and fed via a pump 48 two series-connected heat exchangers 49, 50 and further cooled, which are connected to a cooling system 55 with two cooling circuits, cooling circuit I and cooling circuit II. Via a return line 51 to the second heat exchanger 50, cooled condensate is fed back into the main condenser 44 in countercurrent, as in FIG. 6 seen. As a result, the gas flowing through the packed columns 46 is cooled shock-like. Via the passage 53 at the top, which ends in 39 Figure 1c is equivalent, non-condensed residual gas is either used as combustion gas or it may follow another condenser to be condensed by means of the same existing portions of HCs within the residual gas via a branch line 52 to the second heat exchanger 50 and before the return line 51 is the liquid oil, the target product of the process plant, taken.

The FIG. 7 is different from the FIG. 3 essentially only in that in the melting vessel 7 and in the evaporation vessel 20 in addition heating coils 56, 57 are installed in order to increase the introduction of heat into the masses. These heating coils 56, 57 are for their supply according to the FIG. 7 connected to own heat transfer medium circuits WT circuit 1 and WT circuit 2 of the heat transfer heating system 58, which either gas-fired oil - for example, with the residual gas from the main capacitors 30 and 44 - or electrically heated. When using heating coils, the outer heating jacket can also be omitted.

From 100 kg of dry, clean and pure plastic materials, about 75-90 kg of product oil, 2-12 kg of residues and 2-15 kg of non-condensable gases are produced for thermal utilization in the heating system. The yield of product oil depends, among other things, on the types of plastic that are registered.

Industrial Applicability:

The inventive method or cracking method and the device are industrially applicable in the industries of hygienic workup for the recovery of plastic materials and / or oily residues or plastic waste and / or oily waste.

List of reference numbers:

1

silo

2

Trough conveyor screw

3

Transfer container

4

Plug screw or Stopfwerk

5

Throttle non-return valve

6

entry fitting

7.39

melting tank

8.21

Heating jackets

9.22

agitators

10

sedimentation compartment

11, 12, 13, 25, 26

Rückstandaustragarmaturen

14.43

cooling jacket

15

Rückstandvorkühlbehälter

16

emulsion unit

17

Abrakelvorrichtung

18

Heating of the reheater 19

19

reheater

20

Evaporation tank

23

reheater

27

cracking tower

28

Pipe 28

29

pre-condenser

30, 44

main condenser

34

cooling system

38

heating system

39.53

Disposals

40

Upper filler neck

41

feed

42

liquid level

45

Opening of the main capacitor

46

packed columns

47

management

48

pump

49, 50

heat exchangers

51

return

52

branch line

56, 57

heating coil

A

leaving

Claims (23)

1. A method for recovering fractionated hydrocarbons from recycled plastic fractions and/or from oily residues, whereby the recycled plastic fractions and/or residues are sorted by type and compacted under the exclusion of air using a feed system (1, 2, 3, 4), and the compacted mass is fed into a melting apparatus (7), preferably below the liquid level, and heated up therein, so that a separation into a first liquid phase, a first gas phase and a residue fraction takes place, characterized in that
   the liquid phase and the first gas phase are transported into an evaporation vessel (20) where, under additional input of heat, a second liquid phase and a second gas phase are formed, whereby the second liquid phase is transferred into a reheater (23) and further heated there under additional input of heat, so that a third gas phase is formed, after which the second gas phase from the evaporation vessel (20) and the third gas phase from the reheater (23) are fed into a cracking tower (27), where further cracking of the long-chain hydrocarbons into short-chain hydrocarbons takes place, and the oil gas thus formed is then fed to a condenser (30) in which the oil gas is condensed into liquid oil, whereby the oil constitutes the target product, and the method is carried out making use of a multi-circuit heating system (38) in order to generate the requisite process heat for the melting apparatus (7), for the evaporation vessel (20) and for the reheater (23), whereby oil or salt or gas is used as the heat transfer medium.
2. The method according to Claim 1, characterized in that,
   in order to feed the recycled plastic fractions and/or the oily residues into the melting apparatus (7), a plug screw (4) or a plug mechanism is used within the feed system for compacting the residues in order to remove oxygen, and then feeds them into the melting apparatus below its liquid level.
3. The method according to Claim 1, characterized in that
   the medium and heavy fractions of the hot oil gas or crack gas are cooled off abruptly by quenching with cold condensate to a medium temperature level, resulting, at the same time, in the condensation of medium-chair to long-chain hydrocarbons.
4. The method according to Claim 3, characterized in that,
   in order to carry out the quenching procedure, the gas stream is either drawn into the cold, liquid circulation stream, or else it is fed over two packed beds inside packed columns that are operated in a countercurrent, whereby cold condensate trickles over the packings.
5. The method according to Claim 3, characterized in that,
   thanks to fact that there are two packed columns, one can be regenerated while the other runs in normal operation, whereby for purposes of regeneration, the circulation stream in the packed column that is to be regenerated is switched off and the hot gas stream coming from the cracking tower is fed through the packed column that is to be regenerated, as a result of which the packing therein is heated up, and deposits are removed.
6. The method according to one of the preceding claims, characterized in that,
   for purposes of generating the primary process heat, a non-condensable fraction of the oil gas is thermally utilized by being fed to the heating system in order to fire it.
7. The method according to one of the preceding claims, characterized in that,
   the oil-water emulsion is thermally utilized by being fed to the heating system (38) in order to fire it.
8. The method according to Claim 1, characterized in that
   a pre-condenser (29) and a main condenser (30) are used as condensers, and the excess heat from the pre-condenser (29), from the main condenser (30) and from a residue pre-cooling tank (15) is fed to the heating system (38), whereby the main condenser is connected to a multi-circuit condensation system.
9. The method according to Claim 1, characterized in that
   the recycled plastic fractions and/or oily residues are comminuted after having been sorted and, if applicable, they are dried before the cracking process is carried out.
10. The method according to Claim 1, characterized in that
    the residue fraction inside the melting apparatus (7) is transported into a sedimentation compartment (10) located underneath said melting apparatus (7), where the residue fraction is concentrated, and subsequently, the concentrated residue fraction is transferred into a residue pre-cooling tank (15) where the residue fraction is cooled by means of a cooling medium from a cooling system (34), preferably to a temperature of less than 120°C [248°F].
11. The method according to one of the preceding claims, characterized in that
    the cooled residue fraction is fed to an emulsion unit (16) in which an oil-water emulsion is produced from the residue fraction.
12. The method according to one of the preceding claims, characterized in that,
    between the cracking tower (27) and the main condenser (30), there is a pre-condenser (29) that, in order to recover energy at a high temperature level, pre-cools the oil gas, as a result of which the temperature gradient between the cracking tower (27) and the main condenser (30) is reduced.
13. The method according to one of the preceding claims, characterized in that
    the main condenser (30) and, if applicable, the pre-condenser (29), are connected to a multi-circuit cooling system (34).
14. The method according to Claim 1, characterized in that
    the efficiency of the heating system is maximized in that heat is returned to the system, making use of the residual gas to fire the heating system.
15. The method according to Claim 1, characterized in that
    several optimized temperature levels allow flexible heating of the heating system, namely, by product oil, by product gas as well as by an oil-water emulsion, as well as electrically or through a combination of the various above-mentioned energy carriers, thus yielding the maximum energy utilization.
16. A device for recovering fractionated hydrocarbons from recycled plastic fractions and/or from oily residues, whereby the recycled plastic fractions and/or residues have been sorted by type, having a feed system (1, 2, 3, 4) for compacting the recycled plastic fractions and/or the oily residues under the exclusion of air, and also having a downstream melting apparatus (7) for heating and melting the compacted mass in order to generate a first liquid phase, a first gas phase and a residue fraction, characterized in that,
    downstream from the melting apparatus (7), in order to generate a second liquid phase and a second gas phase under additional input of heat, there is an evaporation vessel (20) which is followed by a reheater (23) in order to introduce and further heat the second liquid phase so that a third gas phase is formed, and a cracking tower (27) is connected to the evaporation vessel (20) and to the reheater (23) in order to crack the long-chain hydrocarbons into short-chain hydrocarbons, whereby a condenser (30) is connected to said cracking tower (27) in order to condense the oil gas into liquid oil as the target product, whereby the device has a multi-circuit heating system (38) in order to generate the requisite process heat for the melting apparatus (7), for the evaporation vessel (20) and for the reheater (23) to temperature levels that have been optimized for this purpose, with oil or salt or gas being used as the heat transfer medium.
17. The device according to Claim 16, characterized in that
    in order to feed the recycled plastic fractions and/or the oily residues into the melting apparatus (7), there is a plug screw (4) or a plug mechanism within the feed system for compacting the recycled plastic fractions and/or the oily residues, upstream from which, if applicable, there is a spherical transfer tank (3) to effectuate the transfer into the plug screw (4) or into the plug mechanism.
18. The device according to Claim 17, characterized in that
    the outlet of the plug screw (4) or plug mechanism opens up into the melting apparatus (7) below the liquid level of the melted mass inside said melting apparatus (7).
19. The device according to Claim 16, characterized in that
    a sedimentation compartment (10) for receiving the residue fraction is arranged underneath the melting apparatus (7).
20. The device according to Claim 19, characterized in that
    a residue pre-cooling tank (15) with an emulsion unit (16) attached thereto is arranged on the sedimentation compartment (10) for purposes of producing an oil-water emulsion out of the residue fraction.
21. The device according to Claim 16, characterized in that
    the condenser consists of a main condenser (30) and a pre-condenser (29), and it is arranged between the cracking tower (27) and the main condenser (30) in order to pre-cool the oil gas of the pre-condenser (29).
22. The device according to Claim 16, characterized in that
    a multi-circuit cooling system (34) is connected to the main condenser (30).
23. The device according to Claim 16, characterized in that
    the melting apparatus (7) and the evaporation vessel (20) as well as, If applicable, the reheater (23) have an externally arranged heating jacket (8, 21) and/or coiled tubes (56, 57), and said heating jackets (8, 21) can be heated up by means of the shared heat-carrier heating system (38).

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