WO2015087235A1

WO2015087235A1 - Recycling of hydrocarbon materials

Info

Publication number: WO2015087235A1
Application number: PCT/IB2014/066722
Authority: WO
Inventors: Harry Dean KASSEL
Original assignee: Kassel Harry Dean
Priority date: 2013-12-09
Filing date: 2014-12-09
Publication date: 2015-06-18

Abstract

In accordance with this invention there is provided a process for the recycling of hydrocarbon containing articles which includes introducing a feed material containing hydrocarbon articles to a reactor, injecting a liquid stream into the reactor to contact and react with feed material, where the feed material and liquid stream react so as to convert the feed material into a hydrocarbon gas and a partly devulcanized hydrocarbon polymer. The invention provides additionally for the recovery of the hydrocarbon gas and hydrocarbon polymer as well as any unutilized liquid hydrocarbon material from the liquid feed stream.

Description

RECYCLING OF HYDROCARBON MATERIALS

FIELD OF THE INVENTION

This invention relates to a process for recycling hydrocarbon materials from articles containing such.

BACKGROUND TO THE INVENTION

Many articles and products include hydrocarbons and pose a significant environmental problem after the end of the useful life of such articles. The manufacture of hydrocarbons for manufacturing such articles is expensive and in itself poses environmental risks. The materials from which such articles are manufactured include, amongst others and without limitation, rubber, plastics, polymers and elastomers. Motor vehicle tyres and conveyor belts are examples of articles that contain hydrocarbons and pose an environmental risk after use. Certain of these materials are very difficult to recycle. Rubber tyres, both used and recycled, are one example of products made from such very difficult to recycle material, and these pose a huge environmental threat worldwide.

The manufacturing of these rubber articles very often includes vulcanization, which is a chemical process by which rubber and polymers are rendered more durable materials via the addition of sulphur or other equivalent "curatives" or "accelerators". These additives modify the polymer structure by forming crosslinks between individual polymer chains. These materials have superior mechanical properties due to vulcanization. Vulcanized rubber or polymers are therefore more difficult and costlier to recycle.

Numerous processes have been proposed to recycle such hydrocarbon containing materials whether vulcanized or not, and notably for the recycling of tyres. Vehicle tyres are usually composed of synthetic and natural rubbers, plasticizers, carbon black, steel reinforcing wires, metal beads and nylon or polyester fibres, and the rubber therein is typically vulcanized.

The already proposed recycling methods usually involve mechanically reducing tyres by so- called crumbing. Numerous processes have been proposed for this, as evidenced by patents US3843061 , US4235383, US4614308, US4757949, and US5927627. These processes rely on mechanical separation of the components from which tyres are manufactured, resulting in crumbed rubber as an end product, amongst others. The crumbed rubber component remains vulcanized and requires further processing. Other solutions include carbonizing the entire tyre, which breaks down the rubber into carbon char and a fuel oil product. The carbon char has a very limited market, if any. This solution therefore does not eliminate the waste tyre problem, and creates another problem. The fuel oil product is a very unstable product, and is problematic as a fuel since it has a tendency to form gums and it precipitates tars when utilized in a pressurised burner system. A problem with this pyrolysis or carbonization solution is that they yield products that don't attract good economic value. There are limited uses and markets for such products. Based on the above there is limited application for these solutions.

Another approach has been to first soften a tyre with a solvent and then subjecting it to shear conditions to remove the rubber from the reinforcing materials, which is a variation of the crumbing process. The problem with using solvents is that the solvents are expensive and of high economic value, and significant volumes of such solvents are required for this, thus making this particular process of limited economic benefit. Further processes include heating the rubber in the absence of oxygen to high temperatures in the absence of oxygen by making use of microwave energy. A problem with this approach is that rubber is a poor conductor of microwave energy. The rubber is thus unevenly heated by the microwaves which results in incomplete carbonization and possible contamination with combustion products.

A further type of process relates to the use of a mixture of oil and solvents in admixture to contact the rubber and then to applying shearing forces to the softened rubber to recover the elastomeric component. Such a process is described in US6722593 (Dobozy). A problem with this approach is that it still requires the application of shearing forces which calls for additional apparatus that are bulky and costly to operate and maintain, and again only yields a crumb product which has limited application.

A problem of the abovementioned processes is that the rubber or polymer materials remain vulcanized. Devulcanization processes have been proposed to treat rubber and polymers, for example WO01/29122 (Beitakh), but these also involve the crumbing of the vulcanized material, the addition of proprietary dry chemical powders to the crumbs and the mechanical processing of the mixture at a specific pressure and friction ratio through a smooth roll mill. This process has to be repeated multiple times. This is a complicated and costly process and requires the use of proprietary chemicals.

In this specification the term gel is defined as a non-fluid colloidal network or polymer network that is expanded throughout its whole volume by a fluid. It exhibits low to no flow when in the steady-state. In this specification the term slurry is defined as a thin sloppy mud or cement or, in extended use, any fluid mixture of a pulverized solid with a liquid (usually water), often used as a convenient way of handling solids in bulk. Slurries behave in some ways like thick fluids, flowing under gravity but are also capable of being pumped if not too thick. OBJECT OF THE INVENTION

It is an objective of this invention to provide a process and apparatus for recovering elastomeric material from articles that contain such which at least partly overcome the abovementioned problems.

SUMMARY OF THE INVENTION

In accordance with this invention there is provided a process for the recycling of hydrocarbon containing articles which includes providing an input feed containing a combination of any one or more of hydrocarbon-containing rubber, polymeric and elastomeric articles to the process, feeding the feed material to a reactor, providing a liquid hydrocarbon material feed stream to the reactor, injecting the liquid feed stream into the reactor to contact and react with the feed material to convert the feed material and liquid feed stream into hydrocarbon gas and at least partly devulcanized hydrocarbon polymer, recovering from the reactor the hydrocarbon gas, hydrocarbon polymer and any unutilized liquid hydrocarbon material; condensing and recovering a condensable part of the hydrocarbon gas product, scrubbing the remainder of the hydrocarbon gas product to remove impurities and recovering the non- condensable hydrocarbon gas, recovering the unutilized liquid hydrocarbon material from the liquid feed stream, and recovering the hydrocarbon polymer. There is further provided for the liquid feed stream to be heated, preferably to a maximum of 500 °C, and further preferably to between 50 °C and 500 °C.

There is further provided for the process to include heating of the feed material to a maximum of about 500 °C, and further preferably to between 50 °C and 500 °C, and more preferably for the feed material to be heated by means of the heated liquid feed stream.

There is still further provided for the liquid hydrocarbon material in the liquid feed stream to comprise oil, preferably used oil recovered for recycling.

There is also provided for filtering of the liquid feed stream, and preferably for the filtering to include the removal of minerals, metallic components, water and particulate matter from the liquid feed stream, and preferably for the removal of minerals, metallic components and particulate matter to be performed by passing the liquid feed stream through a centrifuge, for water to be removed by means of an evaporator, and for oil and hydrocarbons that have a boiling point at or below about 500 °C present in the liquid feed stream to be evaporated or broken down molecularly.

There is further provided for the liquid feed stream to be injected at substantially constant velocity into the reactor, the velocity preferably being variable, and preferably for the liquid feed stream to be injected through a series of spaced apart apertures, preferably fitted with nozzles, and still further for the liquid feed stream to be injected at a high or low velocity and at a low or high flow rate, at a predeterminable ratio operatively to facilitate optimised recovery of various types of feed material.

According to a further feature of the invention there is provided for the liquid feed stream to include metallic sodium particles, and preferably for the sodium particles to be included in the liquid feed stream at a concentration that exceeds the sulphur concentration in articles to be contacted by the catalyst feed, and further preferably for the concentration of sodium in the liquid feed stream by weight to be about the twice the concentration of sulphur in the articles.

There is still further provided for sulphur in rubber articles to react with sodium in the liquid feed stream to form sodium sulphide, and preferably for the liquid feed stream and feed material to be heated to between about 50 °C and Ι δΟ 'Ό when the liquid feed stream includes sodium particles, more preferably to about 50 °C. There is still further provided for the feed material to be volumetrically expanded by means of increasing its temperature, alternatively by means of a solvent, further alternatively by means of a vacuum applied over the feed material, further alternatively any combination of the above.

The invention also provides for the hydrocarbon polymer recovered from the reaction chamber to be purified by removing carbon black from it, preferably by means of centrifugal or evaporative treatment, and by removing unutilized catalyst from it, preferably by means of vacuum treatment.

There is further provided for the recovered unutilized catalyst feed to be used in the reactor as part of the catalyst feed, and preferably for such recycling of the unutilized liquid feed stream to continue until it becomes unrecoverable or degraded by a predeterminable extent to render it ineffective as a liquid feed stream material.

There is further provided for the recovered condensable part of the hydrocarbon gas product to be cooled, preferably by means of a heat exchanger or fractionating column, further preferably treated, more preferably by being desulfurized, for use as a petrochemical or a fuel.

There is also provided for the recovered non-condensable part of the hydrocarbon gas product to be flared to the atmosphere, thermally oxidised, combusted for heating in the process, for petrochemical feedstock, for agrochemical feedstock, or any combination of the above.

There is also provided for the hydrocarbon polymer to comprise hydrocarbon gel or hydrocarbon slurry, or a mixture thereof.

There is further provided for heating to be performed by means of any one of electrical, steam or any alternative heating means, preferably in a heat exchanger.

According to a further feature of the invention there is provided an at least partly devulcanized hydrocarbon polymer being the product of the process defined above. According to a still further feature of the invention there is provided apparatus for the recycling of hydrocarbon containing articles comprising a reactor configured to receive hydrocarbon articles through a closable door, means to receive and load the hydrocarbon containing articles through the door into the reactor, and including a plurality of jets located around the periphery of the reactor at predetermined locations operatively to direct a liquid reagent feed stream into the reactor to contact and react with the hydrocarbon containing articles.

There is also provided for the apparatus to include a loading chamber located between the reactor and the door, and for the reactor and loading chamber to be separated by a closable valve, configured to allow passage of hydrocarbon containing articles from the loading chamber to the reactor, and for the door to allow access to the loading chamber.

There is further provided for the reactor to be provided with a waste collection chamber, in communication with the reactor by means of a closable valve configured to allow passage of waste material from the reactor to the waste collection chamber, the waste collection chamber including also a door for removal of waste from it.

There is further provided for the apparatus to be arranged in a generally upright manner, with the reactor located above the waste collection chamber which is located on a base, and the loading chamber located above the reactor, with the door to the located above the loading chamber, and for the valve between the reactor and loading chamber to be configured to allow hydrocarbon containing articles loaded in the loading chamber to drop into the reactor under force of gravity when the valve is at least partly opened, preferably fully opened, and for the valve between the reactor and waste collection chamber to be configured to allow waste material from the reactor to drop into the waste collection chamber under force of gravity when this valve is at least partly opened.

There is further provided for the base of the reactor to be provided with a sump for collection and discharge from the reactor of liquid from the reactor, and for the reactor, alternatively the loading chamber, further alternatively both the reactor and the loading chamber to be provided with an off-gas system to collect gaseous products from the apparatus.

The invention also provided for the waste collection chamber to be provided with liquid hydrocarbon spray operatively to spray waste deposited in the waste collection chamber and for a liquid outlet to collect runoff liquid hydrocarbon from the sprays, operatively to cool down the waste before opening the door of the waste collection chamber. There is also provision for control of the operation of the jets into the reaction chamber, and for the control to be configured to shut off liquid reagent feed supply to the jets when the bottom valve is not closed. There is further provided for the valve between the reactor and the loading chamber to comprise a central valve and at least be gas tight and for the valve between the reactor and the waste collection chamber to comprise a lower valve and at least be liquid tight, and further preferably for both the central and lower valves to be gas tight and liquid tight. There is further provided for the door to loading chamber to comprise an upper valve movable between an open and a closed position, and for the upper valve to at least be gas tight, with the upper valve in the closed position sealing the loading chamber from the atmosphere and in the open position or in a partially opened position for the loading chamber to be in fluid communication with the atmosphere.

There is further provided for the central valve to be movable between open and closed positions, with the central valve in the closed position sealing the reaction chamber from the loading chamber, in the open position for the reaction chamber and the loading chamber to be in fluid communication with each other, and further preferably for the central valve in its open position to be unsupportive of hydrocarbon containing articles located in the loading chamber operatively allowing such to drop into the reaction chamber under force of gravity, and for the central valve in its closed position or a partly opened position to prevent hydrocarbon containing articles located in the loading chamber dropping from the loading chamber into the reaction chamber.

There is also provided for the upper valve in its open position or in a partially opened position to allow loading of articles into the loading chamber, and preferably for the upper valve to comprise the door at the upper end of the reactor. There is further provided for the hydrocarbon containing articles to comprise tyres, preferably whole tyres, and for the loading chamber and reactor to be complimentary shaped and configured to receive and locate a plurality of tyres in a stacked configuration, preferably axially aligned with the loading chamber and reactor. There is still further provided for means to receive and load the articles to comprise a loading bracket rotatably movable between a first and a second position, with the loading bracket in the first position being located adjacent the upper end of the loading chamber and in the second position located over the upper valve.

There is further provided for the apparatus to include support means for a tyre above the upper valve, the support means comprising at least one support member extendable between a supporting position, in which it supports a tyre in an axially aligned orientation with respect to the loading chamber, and a non-supporting position, and for the support means to be operable to be moved between the supporting position and the non-supporting position to receive a tyre in axial alignment with the loading chamber and drop the tyre still in axial alignment into the loading chamber.

There is also provided for the support means to comprise three equidistantly spaced apart support members, preferably in the form of rods or plates, and for each rod or plate to be movable between an extended position in which it projects at least partly over the upper valve and a recessed position, in which it does not extend over the upper valve, the support members being configured to be located in their extended positions to receive a tyre from the loading bracket for support thereof, and to substantially uniformly be moved to the recessed position to release such a supported tyre to drop into the loading chamber, operatively allowing a plurality of tyres to be stacked into the loading chamber in an axially aligned orientation with respect to the loading chamber.

There is still further provided for the support members to be pneumatically operated, alternatively any one or more of mechanically, magnetically, electrically or hydraulically. There is further provided for the jets to be provided in a plurality of collars spaced apart along the height of the reactor, with each collar located at a stacking height of a tyre, operatively to direct a jet of catalyst feed to a tyre stacked at such height.

There is further provided for the waste collection chamber to include a discharge door for the removal of waste from it.

There is still further provided for the waste collection chamber to include a reservoir in its base provided with an outlet, and a wheeled collection bin movable on a set of tracks that extend through the discharge door, and further preferably for the bin to be provided with a perforated bottom. There is also provision for control means for the discharge of fluid through the waste collection chamber spray jets, and for the control means to be configured to shut off fluid supply to the waste collection chamber spray jets when the discharge door is not closed or when the temperature of waste inside the waste collection chamber is below a predetermined temperature, with the temperature preferably being determined by comparing a temperature gain between fluid being sprayed into the waste collection chamber and fluid exiting the waste collection chamber from its outlet. There is still further provided for the loading chamber to include a gas collector in the form of an off-gas system to collect gaseous products from the reactor.

There is yet further provided for the reaction chamber to include a sump for the collection of at least partly devulcanized hydrocarbon polymer from the reaction chamber, and preferably for the sump to be located at the base of the reaction chamber.

These and other features of the invention are described in more detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the invention is described by way of example only and with reference to the accompanying drawings in which:

Figure 1 is a plan view of a plant incorporating a reactor according a preferred embodiment of the invention, for performing the method of the invention;

Figure 2 is a plan view of a portion of the plant, showing a conveyer belt feeding the reactor of Figure 1 and outlets from the reactor;

Figure 3 is an elevation view of the reactor and the end of the conveyer belt of Figure

1 ;

Figure 4 is an elevation view of the reactor of Figure 1 with a tyre loaded on the loading bracket;

Figure 5 is a cross sectional elevation view of the reactor of Figure 1 , loaded with tyres in both the loading chamber and reactor core, and with a further loaded on the loading bracket, and a further tyre at the end of the conveyer; Figure 6 is cross sectional elevation view of the reactor of Figure 1 showing the tyres in the loading chamber having been processed, with only solids remaining in the reactor core;

Figure 7 is cross sectional elevation view of the reactor of Figure 1 showing the remaining solids having been deposited into the waste collection chamber;

Figure 8 is cross sectional elevation view of the reactor of Figure 1 showing the central valve opened to deposit the pre-treated tyres from the loading chamber deposited into the reactor core;

Figure 9 is an elevation view of the reactor of Figure 1 showing the loading bracket loaded with a tyre, and indicating cross section line 10-10;

Figure 10A is a cross sectional view through line 10-10 of Figure 9, showing the valve in the closed position; and

Figure 10B is a cross sectional view through line 10-10 of Figure 9, showing the valve in the open position (as also shown in Figure 7).

DETAILED DESCRIPTION OF THE INVENTION

The preferred embodiment of the process according to the invention is executed in apparatus depicted in the accompanying drawings that is used to process an input feed containing a combination of any one or more of hydrocarbon-containing rubber, polymeric and elastomeric articles to the process. In this instance the feed material used motor vehicle tyres.

The apparatus comprises a reactor (1 ) that is arranged a generally upright manner as shown in Figures 3 to 9.

The reactor (1 ) forms part of a larger processing plant (40), shown in in Figure 1 . The plant (40) receives feed of tyres (9) for recycling from a conveyer belt (10). The tyres (9) are fed to the reactor (1 ). The recycled product from the reactor (1 ) is fed through filters and pumps (41 ) to a set of heat exchangers (17). Product from the heat exchangers (17) is fed to a thermal cracker (42) to convert recovered product into a fuel. Additional aspects of the plant include oil storage vessels (43) and coolers (44).

The reactor (1 ) comprises a reactor core (2) located above a waste collection chamber (3) which extends above a base (4), and a loading chamber (5) located above the reactor core (2). The reactor (1 ) includes an upper valve (6) forming a door into the top of the loading chamber (5), a central valve (7) between the reactor core (2) and loading chamber (5), and a lower valve (8) between the reactor core (2) and the waste collection chamber (3). The reactor (1 ) is secured in position by a frame (23), as shown in Figure 3, and the reactor (1 ) forms part of a system as shown in Figure 1 .

The intended purpose of the reactor (1 ) is the recycling of whole motor vehicle tyres, typically used motor vehicle tyres (9). The tyres (9) are heated to a maximum of about 500 °C and are then fed to the top of the reactor (1 ) by means of a conveyor belt (10), as shown in Figures 1 to 3 and 5 to 8.

One tyre at a time is placed into a loading bracket (1 1 ). The loading bracket (1 1 ) is pivotally moveable between a first receiving position, where it is level with and adjacent the upper end of the conveyor belt (10).

Once a tyre (9) is placed on the loading bracket (1 1 ), it is pivoted as shown in Figures 3 and 8 to turn the tyre (9) by 180° to be upside down (compared to its initial position in the loading bracket) and deposit it on tyre support means in the form of holding rods (12).The tyre (9) is thus flipped over and axially aligned with the reactor (1 ).

To prevent a tyre (9) from simply falling into the reactor (1 ) in an uncontrolled manner and possible landing in a manner in which it is not axially aligned with it, the reactor (1 ) includes three holding rods (12) configured to receive and support a tyre (9) in an axially aligned orientation with respect to the reactor (1 ) and to release the tyre (9) for stacking in the reactor (1 ) in a controlled manner. The holding rods (12) extend into the top opening (13) of the reactor (1 ) above the upper valve (6).

The set of holding rods (12) includes three equidistantly spaced apart pneumatically operated rods. Each rod is movable between an extended position in which it projects into the opening (13) above the upper valve (6) and a recessed position, in which it does not extend into the opening (13). The rods are configured to be located in their extended positions to support a tyre (9) on its side wall. Since there are three rods, the tyre (9) is prevented from dropping into the reactor (1 ). Once the tyre (9) is supported and the loading bracket (1 1 ) pivoted to the receiving position, the set of rods (12) are pneumatically moved to the recessed position. Since all three rods are retracted at the same time and the movement is relatively fast, the tyre (9) drops into the reactor (1 ) in an axially aligned orientation to it.

The holding rods (12) are pushed into the opening (13) again, ready to accept another tyre from the loading bracket (1 1 ). The next tyre is similarly dropped into the loading chamber (5) to come to a rest on the first tyre (9). This process is repeated until six tyres are loaded into the loading chamber (5), which is its capacity for more or less standard motor vehicle tyres (9). With a first charge, the reactor core (2) is still empty, and the lower valve is kept closed. The central valve (7) is opened which allows the stack of tyres to drop into the reactor core (2), still in axial alignment with the reactor (1 ). The central valve (7) is then closed to support a new tyre loaded through the upper valve (6). Six more tyres are loaded to fill the loading chamber (5), thus forming a stack of tyres (19) supported by the central valve (7). The reactor (1 ) will now have six tyres (18) in the reactor core (2) and six tyres (19) in the loading chamber (5), as shown in Figure 5.

The number of tyres that can be loaded into the reactor (1 ) depends on the size of the tyres, and could for wider tyres be about five in number.

The structure of the central valve (7) is shown in Figures 10A and 10B. The central valve (7) comprises a set of arms (24) secured to a plate (25) between them. The plate (25) is provided with a circular aperture (26), which is operatively axially aligned with the reactor (1 ). A gate (27) is slidably secured to the set of arms (24) by means of complimentary shaped rods (28). The gate (27) includes a plate (29) between its two rods (28). A brace (30) extends between the two rods (28) on one end.

The gate (27) is movable between a closed position as shown in Figure 10A, and an open position as shown in Figure 10B. The gate (27) may also be located at any point between the open and closed positions, allowing for a partially open (or closed) valve.

To move the gate (27) a pneumatic cylinder is secured to the brace (30).

The aperture (26) of the plate (25) is shaped and sized to be larger than the outer diameter of the largest sized tyres that the reactor (1 ) is intended to recycle. This means the largest sized tyre will pass through the aperture (26), when the gate (27) is opened. By partially closing the valve (27), tyres located above it will still be supported, with gas flow through the valve (7) possible. In the instance of the central valve (7), this allows heated gas from the reaction chamber (2) to pass into the loading chamber (5) to preheat the tyres (19) located therein.

The central valve (7) is thus generally kept partially open during treatment of tyres (18) in the reactor (1 ). The lower and upper valves (6, 8) are kept closed during treatment. Also as shown in Figure 5, liquid reagent is now injected through a set of jets that terminate within the reactor core (2). The jets are arranged around the cylindrical wall (14) of the reactor core (2) in a circumferential collar within the reactor (1 ). There are several of these collars spaced along the height of the reactor core (2), which provide a series of rings of jets around the tyres (18) stacked in the reactor core (2). The jets are all directed to the longitudinal axis of the reactor core (2). The liquid reagent is sprayed (20) onto the tyres (18) in the reactor core (2).

The liquid reagent feed stream that is sprayed into the reactor core (2) comprises liquid hydrocarbon material. In this preferred embodiment the liquid hydrocarbon comprises used motor vehicle oil. It is possible to utilize the liquid reagent feed stream with or without an additive in the form of particles of metallic sodium. The sodium is processed to a fine powder, having a grid size in the range of microns. The fine size of the sodium particles increases its surface area dramatically. The sodium is mixed with the liquid hydrocarbon of the reagent feed stream.

When the liquid reagent is used without the sodium particles the liquid reagent feed stream is heated up to as much 500 °C. This is done in one the heat exchangers (17) shown in Figure 1 and Figure 5. It is preferably heated to between about 260 °C and 500 °C. The increased temperature increases the reaction rate by expanding the tyres (18) and allowing for faster and deeper penetration of the liquid reagent feed stream into the tyre structure.

When the liquid reagent feed stream is used with the sodium particles, the feed stream is heated up to between about 50°C and about Ι δΟ 'Ό. Preferably it is heated only to about 50 °C, which gives optimal results and does not require excessive heating expenses. Before injecting (20) it through jets into the reactor core (2), the liquid reagent feed stream is also filtered for the removal of minerals, metallic components, water and particulate matter from the input feed. This is achieved by passing the liquid feed stream through a centrifuge to remove minerals, metallic components and particulate matter. Water is removed by means of an evaporator. Oil and hydrocarbons that have a boiling point at or below about 500 °C present in the input feed is evaporated or broken down molecularly. When sodium is added to the liquid reagent feed stream it is very important to drive all water off the feed material and from the oil used in the liquid reagent feed stream. Sodium will react with any water to burn. This is not necessarily a fire hazard since it will be contained in the reactor core (2). However, this will create undesired conditions within the reactor (1 ) and it will diminish the level of sodium available to react with the sulphur in the tyres (18).

The heated and filtered liquid reagent feed stream is injected (20) into the reactor core (2) through the nozzles within the reactor core (2), all of which are directed to the longitudinal axis of the reactor (1 ). The liquid reagent feed stream is injected at uniform velocity through all of the nozzles. The velocity is variable depending on the process requirements.

As mentioned above and shown in Figure 5, the liquid reagent feed stream contacts the stacked tyres (18) in the reactor core (2) and through a combination of thermal, chemical and mechanical action the vulcanized rubber in the tyres is at least partly devulcanized. The rubber is converted into a gaseous hydrocarbon phase and a gel hydrocarbon phase.

The injection of the liquid reagent feed stream into the reactor core (2) increases the temperature of the tyres in the reaction core (2). The temperature in the reaction chamber (2) reaches and stabilises at its operating temperature, which is about equal to the temperature of the liquid reagent feed stream.

The heat and chemical interaction between the reagent and the rubber causes the cross links of the vulcanized rubber to be broken. This is particularly aided by the interaction of sodium particles in the liquid reagent feed stream with the sulphur to form sodium sulphate. The increased temperature of the tyres causes them to swell, which allows the reagent to penetrate the structure of the tyres (18) for faster and deeper contact between the reagent and the rubber. Because these tyres (18) have been preheated in the loading chamber (5), once the first batch has been processed, subsequent processing is faster. As before, the fresh tyres (19) in the loading chamber (5) are preheated by the hot gas from the reaction core (2) passing around them on its way out of the off-gas system (15).

With the devulcanization sodium sulphate is formed which reports generally in the hydrocarbon polymer product at the bottom of the reactor core (2). The tyre is structurally weakened due to the loss of the sulphur, which aids in its degradation. Most of the tyre eventually dissolves into the mentioned products, be it gel or gas or liquid. All that remains are the non-transformable components of the tyre such as metal reinforcing and, to the extent that fibres were used in the manufacture of the tyre, such fibres. These collect at the bottom of the reaction core (2) on top of the lower valve (8), as shown in Figure 6.

The gaseous phase rises to the top of the reactor (1 ) where, under the closed upper valve (6), it is collected the off-gas system (15). The configuration of the off-gas system is shown in schematically in Fig 7.

During the processing of the tyres in the reaction core (2), the tyres stacked in the loading chamber (5) are heated up, as a result of the hot gas from the reaction core (2) passing around the loading chamber tyres (19) on its way out of the off-gas system (15). The lower valve (8) at the bottom of the reactor core (2) is liquid and gas tight. The gel hydrocarbon phase is collected at the bottom of the reactor core (2) where it collects in a sump and is drained through an outlet for further processing.

The above mentioned non-transformable components of the tyres collect at the bottom of the reactor core (2) on top of the closed lower valve (8) where it can be dropped into the waste collection chamber (3). A portion of the liquid reagent stream remains unreacted and this is also collected in the sump at the bottom of the reactor core (2) to be used again as part of the liquid reagent to contact tyres. The products and unreacted reagent of the process are thus collected in the off-gas system (15) and in the sump of the reactor core (2).

The gaseous phase includes a condensable and a non-condensable component. The condensable component of the hydrocarbon gas is condensed by means of cooling in a heat exchanger (17), as shown in Fig 1 . The condensed hydrocarbon product from this is separated into its component parts by means of a fractionating column, based on the differences in their volatilities. This yields a liquid petrochemical or fuel product. This is collected and desulfurized for its use as a petrochemical or fuel.

The non-condensable hydrocarbon gas is scrubbed in a scrubber to remove impurities and then flared to the atmosphere. This scrubbed gas may also be thermally oxidized, used for heating purposes in the process to preheat the tyres or the liquid reagent feed stream or the reactor (1 ). Alternatively, this scrubbed gas may also be used as a petrochemical or agrochemical feedstock, or a combination of any of the mentioned applications or uses. The hydrocarbon gel phase is collected as a product and this is used for any or all of a fuel, a fuel oil, a petrochemical, a petrochemical feedstock, in asphalt applications, as a sealant, as a component in polymeric and elastomeric products, as a component in the manufacture of any of the above, or as a component in the compounding in part or as a whole of any elastomeric or polymeric or rubber or vulcanized or un-vulcanized products.

When the requisite time has passed for completion of the reaction, the spraying of liquid reagent through the jets onto the tyres (18) is stopped. Once the remaining gel and liquid have been drained from bottom of the reactor core (2), the lower valve (8) is opened, as shown in Figure 7. This allows the waste (21 ) from the reactor core (2) to drop into the waste collection chamber (3). The lower valve (8) is closed again. At this point the outer door (16) of the waste collection chamber (3) still remains closed.

The central valve (7) is now opened fully which allows the tyres (19) from the loading chamber (5) to drop into the reactor core (2). This leaves the loading chamber (5) empty again. The central valve (7) may now be closed over the already partially preheated tyres that dropped into the reactor core (2). This is done to prevent unnecessary heat loss from the already partially heated tyres. The upper valve (6) is then opened to load six more tyres into the loading chamber (5) as per the already mentioned loading procedure. Once so loaded, the upper valve (6) is closed and the central valve (7) partially opened to put the reactor core (2) in fluid communication with the loading chamber (5).The process to treat the tyres in the reactor core (2) then commences again with spraying of liquid reagent onto the tyres, as mentioned above.

The waste (21 ) that had been allowed to drop into the waste collection chamber (3) would still be hot when it drops into it. The waste includes some hydrocarbon liquid and is flammable. To prevent unwanted flaring of this waste in the waste collection chamber, it is first cooled down by spraying oil over it.

The oil is sprayed through a spray jet located within the waste collection chamber (3), and the run-off oil is collected in a sump in the base of the waste collection chamber (3) for recycling. The temperature of the run-off oil is monitored to determine when the waste has been cooled down sufficiently. When the waste is still hot the oil sprayed on it will heat up, which will report as an increase in the temperature of oil collected from the sump. This is compared to the temperature of the oil sprayed on the waste to determine a differential. When the differential is zero or sufficiently small it indicates that the waste (21 ) has been cooled down sufficiently.

Once the waste (21 ) has been cooled down sufficiently, the door (16) is opened to allow removal of the waste (21 ). The waste collection chamber (3) has capacity for waste (21 ) from more than six tyres, which means it does not have to be cleared after each batch of tyres (18) has been treated in the reactor (1 ). Instead, it is possible to operate the reactor (1 ) for several hours, or even most of a day before the waste collection chamber (3) needs to be cleared. The waste collection chamber (3) is provided with a collection bucket that is fitted with wheels and which is movable on a track that extends from inside the waste collection chamber (3) through the base (4) at its door (16), above its sump. The bucket has an opening at the top that extends beyond the opening of the lower valve (8), allowing all of the waste to drop from the reactor core (2) into the bucket.

The door (16) of the waste collection chamber (3) is provided with a sight-glass (22) allowing visual inspection of the bucket, thus ensuring that it can be emptied before it overfills.

In this manner the tyres (5) are processed through the reactor (1 ). The product from the process includes the hydrocarbon gel and the hydrocarbon gas, which are treated as described above.

By making use of the invention it is possible to recycle hydrocarbon containing articles at a relatively low temperature and without the requirement of costly chemicals. An added benefit is that the hydrocarbon containing articles, where it has been vulcanized, is at least partly devulcanized which provides an improvement over current complicated and costly recycling processes for vulcanized hydrocarbon materials. It will be appreciated that the embodiment of the invention described above is given by way of example only and is not intended to limit the scope of the invention. It is possible to alter aspects thereof without departing from the essence of the invention.

Claims

A process for the recycling of hydrocarbon containing articles which includes providing an input feed containing a combination of any one or more of hydrocarbon- containing rubber, polymeric and elastomeric articles to the process, feeding the feed material to a reactor, providing a liquid hydrocarbon material feed stream to the reactor, injecting the liquid feed stream into the reactor to contact and react with the feed material to convert the feed material and liquid feed stream into hydrocarbon gas and at least partly devulcanized hydrocarbon polymer, recovering from the reactor the hydrocarbon gas, hydrocarbon polymer and any unutilized liquid hydrocarbon material; condensing and recovering a condensable part of the hydrocarbon gas product, scrubbing the remainder of the hydrocarbon gas product to remove impurities and recovering the non-condensable hydrocarbon gas, recovering the unutilized liquid hydrocarbon material from the liquid feed stream, and recovering the hydrocarbon polymer.

A process as claimed in claim 1 in which the liquid feed stream is heated to a maximum of 500 °C.

A process as claimed in claim 1 in which the liquid feed stream is heated to between 50 °C and 500 °C.

A process as claimed in any one of claims 1 to 3 which includes the step of heating the feed material to a maximum of about 500 °C.

A process as claimed in any one of claims 2 to 4 in which the feed material is heated by means of the heated liquid feed stream.

A process as claimed in any one of claims 3 to 5 in which the liquid hydrocarbon material in the liquid feed stream comprises oil, preferably used oil recovered for recycling.

A process as claimed in any one of claims 1 to 6 which includes the step of filtering of the liquid feed stream for the removal of minerals, metallic components, water and particulate matter from the liquid feed stream by passing the liquid feed stream through a centrifuge, including an evaporator for the removal of water.

8. A process as claimed in claim 7 in which oil and hydrocarbons that have a boiling point at or below about 500 °C present in the liquid feed stream is evaporated or broken down molecularly.

9. A process as claimed in any one of claims 1 to 8 in which the liquid feed stream is injected at substantially constant velocity into the reactor.

10. A process as claimed in claim 9 in which the injection velocity of the liquid feed stream is variable, and the liquid feed stream is injected through a series of circumferentially spaced apart apertures, and each aperture is preferably fitted with a nozzle.

1 1 . A process as claimed in claim 9 or 10 in which the liquid feed stream is injected at a high or low velocity and at a low or high flow rate, at a predeterminable ratio operatively to facilitate optimised recovery of various types of feed material.

12. A process as claimed in any one of claims 1 to 1 1 in which the liquid feed stream includes metallic sodium particles at a concentration that exceeds the sulphur concentration in articles to be contacted by the catalyst feed.

13. A process as claimed in claim 12 in which the concentration of sodium in the liquid feed stream by weight is about the twice the concentration of sulphur in the articles.

14. A process as claimed in claim 12 or 13 in which the liquid feed stream and feed material is heated to between about 50°C and Ι δΟ 'Ό when the liquid feed stream includes sodium particles, operatively allowing the sulphur in rubber articles to react with sodium in the liquid feed stream to form sodium sulphide.

15. A process as claimed in claim 14 in which the in which the liquid feed stream and feed material to be heated to about 50 °C.

16. A process as claimed in any one of claims 1 to 15 which includes the step of increasing the temperature of the feed material to volumetrically expand it, alternatively adding a solvent, further alternatively applying a vacuum over the feed material to volumetrically expand the feed material, further alternatively any combination of the above.

17. A process as claimed in any one of claims 1 to 16, which includes the step of recovering hydrocarbon polymer from the reaction chamber for purification by removing carbon black from it by means of centrifugal or evaporative treatment and by removing unutilized catalyst from it by means of vacuum treatment.

18. A process as claimed in claim 17 which includes the step of using recovered unutilized catalyst feed in the reactor as part of the catalyst feed, and for such recycling of the unutilized liquid feed stream to continue until it becomes unrecoverable or degraded by a predeterminable extent which renders it ineffective as a liquid feed stream material.

19. A process as claimed in claim 17 or 18, which includes the step of cooling the recovered condensable part of the hydrocarbon gas product by means of a heat exchanger or fractionating column.

20. A process as claimed in claim 19 in which the recovered condensable part of the hydrocarbon gas product is treated by being desulfurized for use as a petrochemical or a fuel.

21 . A process as claimed in any one of claims 1 to 20 which includes the step of flaring the recovered non-condensable part of the hydrocarbon gas product to the atmosphere, alternatively the process includes the step of thermal oxidisation or combustion for heating in the process; alternatively the step of using the recovered non-condensable part of the hydrocarbon gas product for petrochemical feedstock, for agrochemical feedstock, or any combination of the above.

22. A process as claimed in any one of claims 1 to 21 in which the recovered hydrocarbon polymer comprises hydrocarbon gel or hydrocarbon slurry, or a mixture thereof.

23. A process as claimed in claim 22 in which the heating is performed by means of any one of electrical, steam or any alternative heating means, preferably in a heat exchanger.

24. An at least partly devulcanized hydrocarbon polymer being the product of the process as claimed in any one of claims 1 to 23.

25. Apparatus for the recycling of hydrocarbon containing articles comprising a reactor configured to receive hydrocarbon articles through a closable loading door, means to receive and load the hydrocarbon containing articles through the loading door into the reactor, and including a plurality of spray jets equidistantly spaced apart around the periphery of the reactor at predetermined locations operatively to direct a liquid reagent feed stream into the reactor to contact and react with the hydrocarbon containing articles.

26. Apparatus as claimed in claim 25 which includes a loading chamber located between the reactor and the loading door, and the reactor and loading chamber is separated by a closable valve configured to allow passage of hydrocarbon containing articles from the loading chamber to the reactor, with the loading door allowing access to the loading chamber.

27. Apparatus as claimed in claim 25 or 26 in which the reactor is provided with a waste collection chamber in communication with the reactor by means of a closable valve configured to allow passage of waste material from the reactor to the waste collection chamber, with the waste collection chamber including a closable discharge door for removal of waste from it.

28. Apparatus as claimed in any one of claims 25 to 27 which is arranged in a generally upright manner, with the reactor located above the waste collection chamber which is located on a base, and the loading chamber located above the reactor, with the loading door located above the loading chamber, and the valve between the reactor and loading chamber is configured to allow hydrocarbon containing articles loaded in the loading chamber to drop into the reactor under force of gravity when the valve is at least partly opened, preferably fully opened, and the valve between the reactor and waste collection chamber is configured to allow waste material from the reactor to drop into the waste collection chamber under force of gravity when this valve is at least partly opened.

29. Apparatus as claimed in any one of claims 25 to 28 in which the base of the reactor chamber is provided with a sump in its base for collection and discharge of at least partly devulcanized hydrocarbon polymer from the reaction chamber.

30. Apparatus as claimed in any one of claims 25 to 29 in which the reactor chamber, alternatively the loading chamber, further alternatively both the reactor chamber and the loading chamber are provided with an off-gas system to collect gaseous products from the apparatus.

31 . Apparatus as claimed in any one of claims 27 to 30 in which the waste collection chamber is provided with liquid hydrocarbon spray jets operatively to spray waste deposited in the waste collection chamber with liquid hydrocarbon material, and the waste collection chamber is provided with a liquid outlet to collect runoff liquid hydrocarbon material from the spray jets, operatively to cool down the waste in the waste collection chamber before opening the door of the waste collection chamber.

32. Apparatus as claimed in any one of claims 25 to 31 which includes control means for the operation of the spray jets in the reaction chamber, with the controls means configured to shut off liquid reagent feed supply to the spray jets when the bottom valve is not closed.

33. Apparatus as claimed in any one of claims 25 to 32 in which the valve between the reactor and the loading chamber comprises a central valve that is at least be gas tight and the valve between the reactor and the waste collection chamber comprises a lower valve that is at least liquid tight, and both the central and lower valves are preferably gas tight and liquid tight.

34. Apparatus as claimed in any one of claims 25 to 33 in which the loading door comprises an upper valve movable between open and a closed positions, and the upper valve is at least gas tight, with the upper valve in the closed position sealing the loading chamber from the atmosphere, and the upper valve in the open position or in a partially opened position placing the loading chamber in fluid communication with the atmosphere.

35. Apparatus as claimed in claim 33 and 34 in which the central valve is movable between open and closed positions, with the central valve in the closed position sealing the reaction chamber from the loading chamber and the central valve in the open position placing the reaction chamber and the loading chamber in fluid communication with each other, and the central valve in its open position being unsupportive of hydrocarbon containing articles located in the loading chamber operatively allowing such articles to drop into the reaction chamber under force of gravity, and for the central valve in its closed position or a partly opened position preventing hydrocarbon containing articles located in the loading chamber dropping from the loading chamber into the reaction chamber.

36. Apparatus as claimed in claim 35 in which the upper valve in its open position allows loading of articles into the loading chamber, and the upper valve to preferably comprises the loading door at the upper end of the reactor.

37. Apparatus as claimed in any one of claims 25 to 36 in which the hydrocarbon containing articles comprises tyres, preferably whole tyres, and the loading chamber and reactor are complimentary shaped and configured to receive and locate a plurality of tyres in a stacked configuration, preferably axially aligned with the loading chamber and reactor.

38. Apparatus as claimed in claim 37 in which the means to receive and load the tyres comprises a loading bracket complimentary shaped to a tyre rotatably movable between a first and a second position, with the loading bracket in the first position located adjacent the upper end of the loading chamber and in the second position located over the upper valve.

39. Apparatus as claimed in claim 38 in which the apparatus includes support means for a tyre above the upper valve, the support means comprising at least one support member extendable between a supporting position, in which it supports a tyre in an axially aligned orientation with respect to the loading chamber, and a non-supporting position, and the support member is operable to be moved between the supporting position and the non-supporting position to receive and support a tyre in axial alignment with the loading chamber in the supporting and to drop the tyre still in axial alignment into the loading chamber when the support member is moved to the non- supporting position.

40. Apparatus as claimed in claim 39 in which the support means comprises three equidistantly spaced apart support members, preferably in the form of rods or plates, and each rod or plate is movable between an extended position in which it projects at least partly over the upper valve and a recessed position in which it does not extend over the upper valve, the support members being configured to be located in their extended positions to receive a tyre from the loading bracket for support thereof, and to be substantially uniformly moved to the recessed position to release such a supported tyre to drop into the loading chamber, operatively allowing a plurality of tyres to be stacked into the loading chamber in an axially aligned orientation with respect to the loading chamber.

41 . Apparatus as claimed in claim 40 in which the support members are pneumatically operated, alternatively any one or more of mechanically, magnetically, electrically or hydraulically.

42. Apparatus as claimed in claim 41 in which the jets are provided in a plurality of collars spaced apart along the height of the reactor, with each collar located at a stacking height of a tyre and including a plurality of equidistantly spaced apart jets, operatively to direct a jet of catalyst feed to a tyre stacked at such height.

43. Apparatus as claimed in any one of claims 27 to 42 in which the waste collection chamber includes a reservoir in its base provided with an outlet, and a wheeled collection bin movable on a set of tracks that extend through the discharge door, and further preferably for the bin to be provided with a perforated bottom.

44. Apparatus as claimed in any one of claims 31 to 43 which includes control means for the discharge of fluid through the waste collection chamber spray jets, the control means configured to shut off fluid supply to the waste collection chamber spray jets when the discharge door is not closed or when the temperature of waste inside the waste collection chamber is below a predetermined temperature, with the temperature preferably being determined by comparing a temperature gain between fluid being sprayed into the waste collection chamber and fluid exiting the waste collection chamber from its outlet.