Method and System for Hydrocarbon Extraction

Abstract

The invention provides a process and system for the depolymerisation of hydrocarbon-containing material for producing diesel oil and/or heating oil comprising a reactor adapted to exceed temperature operation of 390 degrees Celsius and provided with a plant specific exothermal heat source. In a preferred embodiment, raw materials enter the reactor in a liquid or viscous state by pre-heating and introducing it under pressure to the specially adapted reactor where further heating of the raw material takes place under vacuum.

Description

FIELD OF THE INVENTION

The invention relates to hydrocarbon extraction from mineral oil and carbon based raw materials and residues in a continuous fashion. In particular the invention relates to a method for the depolymerisation of hydrocarbon-containing residues or material, especially for the production of diesel oil and/or heating oil.

BACKGROUND TO THE INVENTION

For the depolymerisation of hydrocarbon-containing residues, especially for generating diesel oil, plastics, oils, grease, dried refuse, electrical cables, wood, paper, digested sludge, agricultural residues, natural fibers, and many other old or discarded or residue materials are depolymerised catalytically with the goal of obtaining the fewest possible solid and gaseous conversion products.

For the presence of ion-exchanging catalysts, the depolymerisation process, i.e., the molecule-shortening of the long-chained hydrocarbon compounds, takes place relatively quickly due to catalytic cracking. Here, the hydrocarbon molecules settle on the catalysts until they have reached the reaction temperature-dependent on the type of residue- and the degradation products vaporize. Typically, a fluid/catalyst mixture is conducted in a cycle between the evaporation temperature and the raw-material feed-in temperature. By feeding in raw material, the mixture temperature is lowered. The evaporation temperature of the desired and lower boiling fractions are reached again in a heater, such as a tubular heat exchanger, following in the cycle. The components remaining as a liquid are fed back to the raw-material feed-in. The agglomerations forming from catalyst material and higher boiling components of the raw material in this cycle process are transferred outward for further processing.

The vapour fraction leaving the cycle is fractionated in a distillation system, producing, e.g., diesel oil or heating oil. Gaseous components are combusted under the production of hot combustion gases, which provide the quantity of heat necessary for evaporation, and the process temperature (cracking temperature) in the liquid cycle. If the raw material contains chlorine, sulphur, phosphorus, and/or other components that are not desired in the product (diesel oil or heating oil), these are removed in the cycle process. This takes place, e.g., through the use of calcium aluminium silicate or sodium aluminium silicate as an ion-exchanging catalyst and through the addition of, e.g., lime for the purpose of binding the chlorine, sulphur, or phosphorus components to be removed from the raw material.

However a problem with existing systems is that they are complex and not very efficient in extracting or distilling diesel or heating oil from waste material. The present invention aims to provide a simple system and method to overcome the above mentioned problems.

SUMMARY OF THE INVENTION

According to the present invention there is provided, as set out in the appended claims, a system for the depolymerisation of hydro-carbon containing material for producing diesel oil and/or heating oil comprising:

• • a reactor;
  • means for pre-heating raw hydro-carbon containing material to a fluidic or viscous state and introducing said pre-heated material under pressure into said reactor; and
  • means for further heating of the raw material under vacuum in said reactor such that that the raw material under vacuum is heated to a desired temperature range;
  • means for extracting vapour from said heated raw material to an evaporator area and producing said diesel oil or heating oil.

In one embodiment the desired temperature range operates in the range of 390 to 420 degrees C.

In one embodiment there is provided means for removing heated raw material after vapour extraction from said reactor at intervals to a holding and cooling storage vessel.

In one embodiment the reactor comprises a heating jacket provided substantially around the reactor to define a heating space between the outer surface of the reactor and the inner surface of jacket.

In one embodiment said means for heating comprises means for hot gas to be supplied from a burner and blower system through an inlet to the heating space.

In one embodiment there is provided means for evenly distributing a film of heated raw material on the inside surface of said reactor.

In one embodiment the reactor is substantially cylindrical in shape and the means for evenly distributing the material comprises a rotor blade rotating about an axis of said reactor.

In one embodiment said blade is dimensioned to provide a gap between the inner surface of the reactor and the end of the blade to define the thickness of the film of heated raw material.

In one embodiment the gap is selected to generate a highly turbulent zone to provide for high the transfer values to allow vapour to be extracted to the evaporator area.

In one embodiment the reactor is conical shaped such that the heated raw material being processed is continuously fed into the largest diameter of the reactor and spread towards the shortest diameter end of the reactor.

In one embodiment the reactor comprises a short path distillation column.

In a further embodiment of the invention there is provided a process for the depolymerisation of hydro-carbon containing material for producing diesel oil and/or heating oil, said process comprising the steps of:

• • pre-heating raw hydro-carbon containing material to a fluidic or viscous state and introducing said pre-heated material under pressure into a reactor;
  • further heating of the raw material under vacuum in said reactor such that that the raw material under vacuum is heated to a desired temperature range;
  • extracting vapour from said heated raw material to an evaporator area and producing said diesel oil or heating oil wherein the desired temperature range operates substantially in the range of 390 to 420 degrees C.

In another embodiment of the invention there is provided a system for the depolymerisation of hydrocarbon-containing material for producing diesel oil and/or heating oil comprising a reactor or short path distillation column adapted to exceed temperature operation of 390 degrees Celsius and provided with a plant specific exothermal heat source. In a preferred embodiment, raw materials enter the column in a liquid or viscous state by pre-heating and introducing it under pressure to a specially adapted device where further heating of the raw material takes place under vacuum.

The normal working temperature of a short path distillation column is in the range of 270 to 390 degrees C. In the case of the inventive process the temperature is now raised to the operating range of 390 to 420 degrees C. It was surprisingly found that this is the optimum temperature to extract the vapours produced.

In one embodiment vapour fraction is continually drawn off and means for releasing solid residues at intervals to a holding and cooling storage vessel.

In one embodiment the short path distillation column can be adapted to accommodate the heating mode and to accept the increase temperature in a heating jacket provided around the short path distillation column.

In one embodiment the short path distillation column provides for hot gas to be supplied from a purpose built burner and blower system.

In one embodiment the short path distillation column is provided with means for the removal of residue from the interior walls of the column, thus enabling a constant and stable heating of the raw material and a high conversion rate.

In one embodiment the short path distillation column is provided with means for removal of residue or solid fraction periodically through an isolating valve system and means for transporting away from the reactor via an extrusion screw to a cooling storage vessel.

In one embodiment the short path distillation column is provided with means to control the mass balance at the vapour stage.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more clearly understood from the following description of an embodiment thereof, given by way of example only, with reference to the accompanying drawings, in which:—

FIG. 1 is a block diagram circuit of a system for the depolymerisation of hydrocarbon-containing material for producing diesel oil and/or heating oil;

FIG. 2 is a 3D perspective view of a system for the depolymerisation of hydrocarbon-containing material for producing diesel oil and/or heating oil, according to a preferred embodiment of the invention; and

FIG. 3 illustrates a reactor according to the invention;

FIG. 4 illustrates a second reactor according to another aspect of the invention;

FIG. 5 illustrates a third reactor according to a further aspect of the invention;

FIG. 6 illustrates a cut through view of the reactor of FIGS. 3 to 5;

FIG. 7 illustrates a second cut through view of the reactor of FIGS. 3 to 5;

FIG. 8 illustrates a fourth reactor according to another aspect of the invention; and

FIG. 9 is a 3D perspective view of a system for the depolymerisation of hydrocarbon-containing for producing diesel oil and/or heating oil, according to another embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram circuit of a system for the depolymerisation of hydrocarbon-containing material for producing diesel oil and/or heating oil. FIG. 1 shows that raw material 1 composed of plastics and waste oil is heated in a preheating stage 2 to 250[deg.] C. and then fed to a device for pressure injection, such as a pressure and feed pump (injection 3) known for the injection moulding of plastic. This pump permits the direct injection of the raw material into a reactor 4, whose liquid contents are kept by a heater 5 (with, e.g., oil or gas and an exhaust-gas temperature of approximately 800[deg.] C.) at a temperature between approximately 300[deg.] C. and 460[deg.] C., preferably between 340[deg.] C. and 440[deg.] C., and its waste heat is recovered partially in the preheating stage 2, e.g., a recuperative heater.

From the reactor 4, a gaseous fraction is drawn off, which is obtained as product 8 after corresponding handling, like fractionated distillation. Likewise in a known way, the solid matter produced in the reactor is drawn from the reactor 4, usually freed from oil, and obtained as residue 7 and optionally processed further.

It is understood that the reactor 4 can be built in various ways and sizes. Similarly, there are no narrow restrictions for the heater 5.

FIG. 2 is a 3D perspective view of a system for the depolymerisation of hydrocarbon-containing for producing diesel oil and/or heating oil, according to a preferred embodiment of the invention, indicated generally by the reference numeral 10. A reactor 11 is provided where raw hydro-carbon containing material is pre-heated to a fluidic or viscous state and introduced under pressure into the reactor 11. Means 12 for further heating of the raw material under vacuum in said distillation column is provided using a burner, such that that the raw material under vacuum is heated to a desired temperature range to a temperature of between 390 and 420 degrees C. Vapour from said heated raw material is channelled to an evaporator or condenser area 13. The vapour is condensed and channelled off to a holding area 14, thus producing said diesel oil or heating oil.

An important aspect of the invention is shown in FIG. 3 that illustrates a more detailed view of the reactor, indicated generally by the reference numeral 30 which has been adapted to exceed normal temperature operation and comprises a plant specific exothermal heat source. Raw material in a viscous state is fed into the reactor through inlet 31 under pressure. In the case of the inventive process the temperature is now raised to the operating range of 390 to 420 degrees C. It was surprisingly found that this is the optimum temperature to extract the vapours produced. This increase in temperature is achieved by using a specially designed burner and blower system by delivering hot gas fed in through a hot gas inlet 32, thus heating the process by hot exhaust gas (approx 800 degrees C.). The excess heat produced is diverted out through an exhaust gas outlet 33 and used to pre-heat the raw material in the extrusion phase in a closed loop system arrangement. Condensing coolant can be introduced into the reactor though inlet 34 and outlet 35. The vapours or gaseous fractions are distilled at the relative fraction for fuel oil or diesel through outlet 36. During the vapour stage gases that do not convert to fuel oil or diesel are drawn off 37 and are used in fuelling the exothermal heat system, this gas fraction is approximately 3-5% of the raw material used. The system provides for hot gas to be supplied from the purpose built burner and blower system. The reactor 30 can be adapted to accommodate the heating mode and to accept the increase temperature in a heating jacket provided around the reactor.

FIG. 4 illustrates a vertical reactor indicated generally by the reference numeral 40, where the raw material product being processed is continuously fed in above a heating jacket and evenly distributed onto the heating surface by a distribution ring, as described below in detail with respect to FIGS. 6 and 7. The product is picked up by rotor blades and is immediately spread over the heating wall as a highly turbulent thin film. The volatile components evaporate quickly and flow in a counter current to the fluid upwards and pass the rotating separator. Entrained droplets or lather are here ejected and flow back into an evaporator area. The low boilers (product gases freed from any liquid constituents) arrive at the condensation level, a column or another downstream process stage. In certain applications Thin Film Evaporators can be used which work using the Parallel Flow Principle. Here, the separator and the upper vapour nozzle are omitted. Instead, a separator tank is placed below the lower rotor bearing. The high boiler (non-evaporated product components) flows down along the inside of the heating wall in a spiral track, reaches in a single occasion the lower end of the heating are within seconds and will consequently be removed from the evaporator. FIG. 5 illustrates a vertical conical type reactor that can be used in the system and process of the present invention, indicated generally by the reference numeral 50.

The reactor of the present invention is designed to incorporate removal of residue from the interior walls of the column, thus enabling a constant and stable heating of the raw material and a high conversion rate. This can be achieved by a raw material scraper 61, as shown in FIG. 6. The residue or solid fraction is removed periodically through an isolating valve system and is transported away from the reactor via an extrusion screw to a cooling storage vessel.

FIG. 7 illustrates a second cut through view of the reactor of FIGS. 3 to 5. In operation when the preheated fluidic type viscous material comes into touch with a rotor after entering the distillation column it is picked up by a distribution ring and evenly distributed onto to the circumference 71. Then it is gathered by the first rotor blades 72 which are lying beneath and is distributed onto the heated wall as a thin film (preferably sized 0.5-3.5 mm) and can be rotated in a clockwise or counter clockwise direction. The fluid builds a bow wave in front of every rotor blade, as shown in Section II of FIG. 7. This bow wave is picked up by the rotor blade and migrates in the gap 73 between rotor and wall into a highly turbulent zone where an intense heat and mass exchange is happening in a radial direction. The highly turbulent condition provides for high heat transfer values in viscous fluids. Even temperature sensitive products are protected from overheating through the intense product mix in the bow wave. This counteracts against a debris build up on the heating surface.

It is desirable to have counter flow distillation that provides qualitatively improved thermal separation process with counter current flow of fluid or vaporous and fluid phases. Here, an intense mutual tangency of both phases with the biggest possible interfaces is aimed at in order to achieve a good heat- and mass exchange in the reactor. Rectification takes place typically in column apparatuses (using rectification exchange plates, packing beds, packages etc.). These installations enable a close tangency of both phases.

In the formed interfaces of both phases molecular kinetic interactions exist which are characterized by substance diffusion and thermal impulse (combined heat and mass exchange). The major impetuses are the temperature differences between vapour and fluid. The concentrations within the two phases are not in phase equilibrium. This disturbance of equilibrium is the cause of the rectification. In the process of mass and heat exchange the condensed out heavy volatile supplies its condensation heat originating from the evaporation phase to the fluid phase. This heat is used to evaporate the equivalent quantity of light volatile. In order to be able to rectify at least part of the vapours which are exhausted via the distillation column are to be condensed and to be submitted as fluid reflux to the column plate and packing bed.

It will be appreciated that the system and the process of the invention can be implemented in a number of different ways, for example:

(A) Fluidized Bed Combustion Method Suitable for Plastics, Waste Oils and Oil Contaminated Sands

• 1. Preparation of feed stocks (drying, splitting of salts, distilling of the parts vaporisable under atmospheric conditions).
• 2. Thermal pyrolisis of long-chain hydrocarbons (polyolefins and mineral waste oils) under the absence of oxygen.
• 3. Distillation of smouldered products.
• 4. In-process thermal conversion of the waste streams resulting from the process (flue-gas cleaning, burner burns off gaseous volatile matter and short chained hydrocarbons, fuel pellets from the bituminous residue, that can be used in road surfaces, for example)
• 5. Motor utilization of the produced oil in diesel engines within the permitted exhaust emission limits.
• 6. Coupling of known individual processes (such as Fluidized Bed Combustion, Conveyor Screw for oil contaminated sands, Distillation) to an overall process.
• 7. Continuous production of the product at capacities of 500-2000 kg/l per hour; Continuous production of the product at capacities of 500 kg/h-ca. 2000 kg/h
  (B) Abstract of the Process of Diesel Production from Plastics

The process consists of the following production phases:

• 1. Preparation of feed stocks (splitting of salts, distilling of the parts vaporisable under atmospheric conditions), e.g. drying and granulation
• 2. Thin Film Evaporation.
• 3. Distillation.
• 4. In-process thermal conversion of the waste streams during process (flue-gas cleaning).
• 5. Motor utilization of the produced oil in diesel engines within the permitted exhaust emission limits.
• 6. Continuous production of the product at capacities of 500 kg/h-ca. 2000 kg/h.
  (c) Abstract of the Process of Diesel Production from Waste Oils

The process consists of the following production phases:

• 1. Preparation of feed stocks (splitting of salts, distilling of the parts vaporisable under atmospheric conditions), e.g. draining through pre-heating.
• 2. Desulphurisation.
• 3. Thin Film Evaporation.
• 4. Distillation.
• 5. In-process thermal conversion of the waste streams during process (flue-gas cleaning).
• 6. Motor utilization of the produced oil in diesel engines within the permitted exhaust emission limits.
• 7. Continuous production of the product at capacities of 500 kg/h-ca. 2000 kg/h.
  (D) Abstract of the Process of Diesel Production in a Combined Plant for from Waste Oils and Plastics

The process consists of the following production phases:

• 1. Preparation of feed stocks (splitting of salts, distilling of the parts vaporisable under atmospheric conditions), e.g. drying and granulation for plastics; draining through pre-heating for waste oils
• 2. Thin Film Evaporation
• 3. Distillation
• 4. In-process thermal conversion of the waste streams during process (flue-gas cleaning)
• 5. Motor utilization of the produced oil in diesel engines within the permitted exhaust emission limits.
• 6. Continuous production of the product at capacities of 500 kg/h-ca. 2000 kg/h.

FIG. 8 illustrates a fourth reactor according to another aspect of the invention where the reactor is place horizontal to the ground in operation, indicated generally by the reference numeral 80. The product being processed is continuously being fed into the largest diameter of the evaporator, is being picked up by the rotor blades and immediately spread over the heating wall as a highly turbulent thin film. As a result of the conicity, the centrifugal forces which impacts the surrounding fluid ring is split into a force component vertical to the heating wall and into one in the direction of the largest diameter. Thus, a fluid backlog in the direction of the product inlet tube is created. The higher pressure of the fluid at the feeding tube carries the circulating fluid ring towards the smaller diameter. This guarantees that the entire evaporator surface is sprinkled with fluid regardless how much product stock is being evaporated or which volumes are fed in. This eliminates local overheating and damage to the product in de-wetted interface areas. The forming gases (low boilers) flow through the horizontal Thin Film Evaporator in parallel flow and pass the rotating separator. Entrained droplets or lather are being ejected and flow into the concentrate outlet (high boiler). The fluid-free gases enter the condensation vessel, a column or another downstream process stage. It will be appreciated that the same effect described with respect to FIG. 8 is to be found in the vertical conical type reactor.

FIG. 9 illustrates is a 3D perspective view of a system for the depolymerisation of hydrocarbon-containing for producing diesel oil and/or heating oil indicated generally by the reference numeral 90 similar to FIG. 1 and hereinbefore described, except the reactor is placed horizontal to the ground.

It will be appreciated that the system can be controlled by a specially designed software programme enabling the system to run in continuous mode. The complete process is controlled by a specially designed software package. This package enables the operator to control the mass balance at the vapour stage and allows conversion in a continuous fashion.

The embodiments in the invention described with reference to the drawings comprise a computer apparatus and/or processes performed in a computer apparatus to control the system and method of the present invention. However, the invention also extends to computer programs, particularly computer programs stored on or in a carrier adapted to bring the invention into practice. The program may be in the form of source code, object code, or a code intermediate source and object code, such as in partially compiled form or in any other form suitable for use in the implementation of the method according to the invention.

The carrier may comprise a storage medium such as ROM, e.g. CD ROM, or magnetic recording medium, e.g. a floppy disk or hard disk. The carrier may be an electrical or optical signal which may be transmitted via an electrical or an optical cable or by radio or other means.

In the specification the terms “comprise, comprises, comprised and comprising” or any variation thereof and the terms include, includes, included and including” or any variation thereof are considered to be totally interchangeable and they should all be afforded the widest possible interpretation and vice versa.

The invention is not limited to the embodiments hereinbefore described but may be varied in both construction and detail.

Claims

1. A system for the depolymerisation of hydro-carbon containing material for producing diesel oil and/or heating oil comprising:

a reactor;

means for pre-heating raw hydro-carbon containing material to a fluidic or viscous state and introducing said pre-heated material under pressure into said reactor;

means for further heating of the raw material under vacuum in said reactor such that that the raw material under vacuum is heated to a desired temperature range; and

means for extracting vapour from said heated raw material to an evaporator area and producing said diesel oil or heating oil.

2. The system of claim 1 wherein the desired temperature range operates substantially in the range of 390 to 420 degrees C.

3. The system as claimed in claim 1 comprising means for removing heated raw material after vapour extraction from said reactor at intervals to a holding and cooling storage vessel.

4. The system as claimed in claim 1 wherein the reactor comprises a heating jacket provided substantially around the reactor to define a heating space between the outer surface of the column and the inner surface of jacket.

5. The system as claimed in claim 1 wherein said means for heating comprises means for hot gas to be supplied from an external burner and blower system through an inlet to the heating space.

6. The system as claimed in claim 1 comprising means for evenly distributing a film of heated raw material on the inside surface of said reactor.

7. The system as claimed in claim 6 wherein the reactor is substantially cylindrical in shape and the means for evenly distributing the material comprises a rotor blade rotating about an axis of said reactor.

8. The system as claimed in claim 6 wherein the reactor is substantially cylindrical in shape and the means for evenly distributing the material comprises a rotor blade rotating about an axis of said reactor, and said blade is dimensioned to provide a gap between the inner surface of the reactor and the end of the blade to define the thickness of the film of heated raw material.

9. The system as claimed in claim 6 wherein the reactor is substantially cylindrical in shape and the means for evenly distributing the material comprises a rotor blade rotating about an axis of said reactor, and said blade is dimensioned to provide a gap between the inner surface of the reactor and the end of the blade to define the thickness of the film of heated raw material, and the gap is selected to generate a highly turbulent zone to provide for high the transfer values to allow vapour to be extracted to the evaporator area.

10. The system as claimed in claim 1 wherein the reactor is conical shaped such that the heated raw material being processed is continuously fed into the largest diameter of the reactor and spread towards the shortest diameter end of the reactor.

11. The system as claimed in claim 1 wherein the reactor comprises a short path distillation column.

12. The system as claimed in claim 1 wherein the reactor comprises a thin film evaporator.

13. The system as claimed in claim 1 wherein the reactor comprises means for the removal of residue from the interior walls of the reactor, thus enabling a constant and stable heating of the raw material.

14. The system as claimed in claim 1 wherein the reactor comprises means for the removal of residue from the interior walls of the reactor, thus enabling a constant and stable heating of the raw material and the means for removal of residue or solid fraction periodically through an isolating valve system and means for transporting away from the reactor via an extrusion screw to a cooling storage vessel.

15. The system as claimed in claim 1 wherein the reactor is provided with means to control the mass balance at the vapour extraction stage.

16. A process for the depolymerisation of hydro-carbon containing material for producing diesel oil and/or heating oil, said process comprising the steps of:

pre-heating raw hydro-carbon containing material to a fluidic or viscous state and introducing said pre-heated material under pressure into a reactor;

further heating of the raw material under vacuum in said reactor such that that the raw material under vacuum is heated to a desired temperature range;

extracting vapour from said heated raw material to an evaporator area and producing said diesel oil or heating oil wherein the desired temperature range operates substantially in the range of 390 to 420 degrees C.