JPS5944355B2 - Method and apparatus for separating bitumen materials and recovering solvents - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved process for separating bituminous material into various fractions using solvents under elevated temperatures and pressures.

A large number of methods for extracting various fractions from bituminous materials have already been disclosed in the prior art.

The most famous of these is called "propane extraction," in which asphalt material is extracted or recovered from heavy hydrocarbon materials, such as prefixed crude oil, by a single-solvent extraction process using propane as the extractant. be done.

A first example of the prior art uses a solvent other than propane to separate heavy hydrocarbon materials into a small number of fractions (both C2-C4
It is disclosed that the operational difficulties of the prior art associated with the use of hydrocarbon solvents) can be eliminated.

This first example discloses that the separation is carried out using high temperature-pressure techniques and by using pentane as one of a group of suitable solvents.

By carrying out such a method, the distillation yield from heavy hydrocarbon materials is increased.

A second example of the prior art discloses a method for separating heavy hydrocarbon materials into three fractions by using a combination of both propane membrane and pentane membrane processes.

The method includes: (1) mixing heavy hydrocarbon materials with pentane under elevated temperature and pressure to produce a light fraction containing resin and oil; (11) under elevated temperature and pressure; mixing the light fraction with propane to produce a second light fraction containing oil and a second heavy fraction containing resin; and (iii) a small fraction of the resin fraction (
Both include recycling a portion back into the pentane tax source process.

Alternatively, the process involves first treating the heavy hydrocarbon material in a propane source process to produce a heavy fraction containing asphaltenes and resins, and then treating the already obtained asphaltene-resin fraction with and pentane source treatment to produce a second light fraction containing resin and a second heavy fraction containing asphaltenes, and recycling at least a portion of the resin fraction back to the propane source process. It can also be implemented by

A third example of the prior art discloses a dual solvent extraction process for producing three components from a hydrocarbon feedstock including asphaltenes, resins and oils.

mixing the feedstock and a first solvent to form a mixture at a solvent to feedstock volume ratio of about 4:1 or less and introducing the mixture into a first extraction zone maintained at elevated temperature and pressure; do.

In a first extraction zone, this mixture separates into a first solvent-enriched liquid phase consisting of asphaltenes and resin-free oil and a first solvent-enriched liquid phase containing asphaltenes and resin.
of the solvent - resulting in an impoverished liquid phase.

The solvent-depleted liquid phase is then contacted with a second solvent having at least one more carbon atom per molecule than the first solvent and introduced into a second extraction zone.

The temperature and pressure in the second extraction zone are kept lower than in the first extraction zone and this solvent-depleted liquid phase is transferred to the second extraction zone containing the resin.
a solvent-enriched liquid phase and a second phase containing asphaltenes.
The solvent separates into a depleted liquid phase.

A fourth example of prior art is single-solvent extraction that separates heavy hydrocarbon materials into three different components using a two-stage solvent process that varies the solvent-to-feed ratio and temperature at each stage. Discloses the law.

Mixing the feedstock and the solvent at a solvent to feedstock volume ratio in the range of 2:1 to 10:1, and a first solvent comprising an oil-enriched fraction and a first solvent comprising asphaltenes and resin. - a first extraction zone maintained at a temperature and pressure sufficient to separate the mixture into a depleted fraction;

The solvent-depleted fraction is then contacted with an additional amount of solvent in a second extraction zone, which is maintained at a lower temperature and pressure than the first extraction zone.
into the extraction zone and form asphaltic solids.

Next, soluble substances are separated from this asphaltic solid.

Prior art separation methods often use vacuum and/or steam stripping to separate the solvent from its various components.

Such treatment vaporizes the solvent, separates it from the bituminous product, and condenses it for recycling into the separation process.

It has been recognized that some of the bituminous material introduced into the steam stripping equipment may be carried away from the steam stripper along with the vaporized solvent and steam in the form of a fine particle atomization mist.

When the solvent is condensed, these fine particles solidify and settle within the process equipment.

The settled solids eventually block the equipment and cause the bitumen separation process to collapse.

It has now been discovered that the solvent can be separated from the bituminous material by vacuum and steam stripping while preventing the introduction of fine particle size bituminous material into the solvent recovery system.

The process consists of introducing the stream of separated solvent and bituminous material, after depressurization, into a steam stripper which has a specially designed device for introducing the stream.

The bitumen feedstock is first mixed with a solvent and introduced into the first separation zone.

the first separation zone is maintained under elevated temperature and pressure;
The mixture is separated into a liquid first light phase comprising a light bituminous material and a solvent and a liquid first heavy phase comprising a heavy bituminous material and a solvent.

A first light phase is removed from the first separation zone and introduced into a second separation zone for further processing.

The first heavy phase is removed from the first separation zone and passed through a pressure reducing valve to be subjected to pressure reduction treatment.

The reduced pressure results in vaporization of a substantial portion of the solvent contained in the first heavy phase.

Unfortunately, reduced pressure also creates a mist of undesirably fine particle size due to some of the heavy bituminous material.

Next, the resulting mixture of steam mist and liquid substance is introduced into a steam stripper to separate the solvent remaining in the liquid substance.

The steam ripper is equipped with a specially designed inlet horn.

The inlet horn is curved along a portion of the circumference of the steamer tripper.

The white horn has a plurality of vanes with a wavy structure.
) is provided.

The liquid substance introduced into the steam stripper flows into the stripper in such a way that the liquid substance substantially wets the walls and vanes of the horn and then flows down from the horn along the walls of the stripper to the lower portion of the stripper. I'll do what I do.

Introducing the liquid material in this manner results in material of fine particle size impinging turbulently on the wet walls and vanes and becoming retained thereon.

The retained fine particles then flow down the stripper wall with the liquid material.

The remaining solvent dissolved in the liquid material is vaporized by the water vapor introduced into the lower part of the stripper.

The vaporized solvent and steam are then removed from the steam stripper and directed to a solvent condensing device.

The solvent vapor and water vapor are condensed and the resulting liquid stream is removed from the solvent condenser and directed to a solvent surge tank with a water removal device.

Due to the density difference between the solvent and water, the water separates as a heavy phase and is withdrawn from the bottom of the solvent surge tank while the solvent is recycled into the process.

Referring to FIG. 1, a feedstock containing bituminous material is introduced into a first separation zone 18 through conduit 10. As shown in FIG.

Preferably, the feedstock is introduced into the upper portion 12 of the first separation zone 18.

Solvent is introduced through conduit 14 into first separation zone 18 for contact and mixing with the feed.

Preferably, the solvent is introduced into the lower portion 16 of the first separation zone 18.

a solvent to feed volume ratio of about 2:1 to about 20:1;
Sufficient solvent is then introduced into first separation zone 18, preferably within the range of about 8:1 to about 12:1.

It should be understood that higher amounts of solvent can be used, but are unnecessary.

Asphaltene,
A bituminous feedstock consisting of atmospheric distillation residues containing resins and oils is specifically described.

maintaining the first separation zone 18 at an elevated temperature and pressure;
The feedstock mixture is separated into a liquid first light phase containing oil and solvent and a liquid first heavy phase containing asphaltenes, resin and solvent.

More specifically, the first separation zone 18 is maintained at a temperature level within a range from below about 150°C to above the critical temperature of the solvent.

It is desirable to maintain the temperature level above the critical temperature of the solvent.

The pressure level in the first separation zone 18 is maintained at least equal to the vapor pressure of the solvent, provided that the temperature in zone 18 is maintained below the critical temperature of the solvent, and is maintained at or above the critical temperature of the solvent. If so, keep it at least the same as the critical pressure of the solvent.

It is desirable to maintain the pressure level above the critical pressure of the solvent.

In an alternative embodiment of the invention (not shown), conduit 10
The feedstock through the conduit 14 and the solvent through the conduit 14 are directed into the mixing zone before being introduced into the first separation zone 18.

After the feedstock and solvent are thoroughly mixed in the mixing zone, they are introduced as a mixture into the first separation zone 18.

Then, by adjusting the temperature and pressure inside the first separation zone 18, the mixture is separated into a liquid first light phase and a liquid first heavy phase.

Returning again to FIG. 1, the first heavy phase is removed from the first separation zone 18 through conduit 24 and subjected to a reduced pressure treatment through a pressure reducing valve 26 located midway through conduit 24.

It is desirable to reduce the pressure level of the first heavy phase to a level of about 0 to 50 psig.

The pressure drop vaporizes a substantial portion of the solvent in the first heavy phase, but a small amount of solvent remains dissolved in the liquid mixture of asphaltene and resin.

It has been observed that vacuum or flash operations that cause solvent vaporization also cause the formation of undesirable fock or spray mist of asphaltenes and resins of fine particle size.

These particles are dispersed in the vaporized solvent in the form of an aerosol mist.

These fine particles do not easily recombine with liquid asphaltene and resin.

The mixture of vaporized solvent, mist, and liquid asphaltenes and resin is then introduced into a steam stripper to remove the combined liquid asphaltenes and resin (
Any remaining solvent in the association is removed.

The vaporized solvent together with the mist and water vapor is then introduced into a condensing device.

The fine particle size asphaltenes and resins in the vaporized solvent solidify during solvent condensation and settle in other subsequent equipment, including the solvent condenser.

The settling asphaltene and resin particles accumulate in the equipment, eventually clogging the discharge conduit and causing a breakdown of the bitumen separation process.

A common type of feedstock introduction method used in steam strippers is to introduce the feedstock radially.

The radial introduction method has several undesirable drawbacks.

The intense turbulence caused by the jet effect as the feedstock expands into the large volume stripper creates additional droplets of feedstock that become dispersed in the vaporized solvent and water vapor. , and the droplets must then be separated from the solvent and water vapor.

In addition, in the radial raw material introduction method, an eddy is generated in the steam flow, and this eddy causes droplet entrainment sedimentation (entity).
This will impede rain- ment-setting.

The maximum amount of droplet entrainment settling is limited to standard gravitational velocity.

In the solvent fractionation method, the separated crude fraction (crudef
Gravity sedimentation is often not sufficient to maintain a solvent flow of the required quality to recover substantially solids-free solvent from a lactation.

A passage built along the inside of the steam stripper (Ch
The difficulties of radial feedstock introduction are overcome to some extent by using a tangential feedstock introduction scheme in which the mixed phase feedstock is fed tangentially through the anneal.

The tangential introduction method has the following advantages in reducing droplet entrainment:
It has two main advantages compared to the radial feed introduction method.

First of all, the separation of the feedstock into gas and liquid phases is not very rapid.

This minimizes the formation of additional droplets dispersed in the gas phase.

Second, the centrifugal field (centrifugal f
Since the rate of separation due to the droplets is directly proportional to the square of the vapor velocity and inversely proportional to the radius of curvature of the vapor stream, the dispersed liquid droplets coalesce and are deposited on the internal walls of the stripper bath.

Although prior art tangential introduction methods have greatly improved vapor-liquid separation efficiency, there are disadvantages associated with their use.

First of all, around the tangential inlet, the separation efficiency is not really proportional to the increase in gravity.

The main reason for the theoretical reduction in separation efficiency is the re-entrainment of the separated liquid by the vortex flow formed below the tangential inlet.

The downward velocity is too high, causing remixing of vapor and liquid.

Second, in the case of the prior art tangential introduction method, the flow characteristics of the steam as it flows through the circular passage opening into the upper part of the stripper are affected by the vortex flow formed after passing through the passage. It is to be disturbed.

Turbulence is created by the impingement of high velocity flow in the passageway followed by transformation into lower velocity fluid downstream.

The vortices formed after the mixture enters the stripper rapidly increases the cross-sectional area of the flow, creating local velocity-enhancing channels.
The formation of such channels disturbs uniform vapor flow and thus droplet entrainment sedimentation.

The method and apparatus according to the invention overcome at least some of the disadvantages of the tangential introduction method into the steam stripper.

According to the method of the invention, a mixture of vaporized solvent, fine particle size asphaltenes and resin, and liquid asphaltenes and resin is introduced into a steam stripper 28 equipped with specially designed introduction means.

Generally, the introduction means will be such as to introduce into the apparatus, such as a steam strip treatment apparatus, a mixture of at least two components, at least one of which is at least partially vaporized. will be prepared.

When the mixture enters the apparatus, fine particles consisting of at least a portion of other non-vaporized components of the mixture are dispersed in the vaporized portion of the vaporizable component. It has been found that there are particular advantages when using an introduction device.

The introducing device acts in such a way that the mixture is introduced into the device in such a way that a centrifugal movement is imparted to the mixture.

Centrifugal motion is used to increase turbulence within the mixture, thereby causing at least a portion of the non-vaporized components of the mixture to coat or wet the internal surfaces of the device, and to reduce the amount of vaporizable components described above. At least a portion of the fine particles of non-vaporized components dispersed in the vaporized portion are caused to impinge turbulently on the coating or wetted surface of the device.

When the fine particles collide with a wet surface, they coalesce with the unvaporized components of the mixture coated on the surface.
sce) L, or adhere to the component
These fine particles exhibit a tendency to

This coalescence or adhesion separates the fine particles from the amalgamation of the vaporizable component with the vaporized portion.

Next, FIG. 2, which is one specific embodiment of the present invention, will be explained.

A mixture of vaporized solvent, fine particle size asphaltenes and resin, and liquid asphaltenes and resin is introduced into the steam stripper 28 through an inlet horn 30 extending along at least a portion of the circumference of the stripper. .

The inlet horn 30 includes at least three solid
) at least one channel having side walls;
).

The fourth sidewall forming the bottom of the passageway may be absent, may be present for a portion of the length of the passageway, or may be present for the entire length of the passageway.

Preferably, one of the side walls of the passageway comprises the inner wall of the steam stripper 28.

A plurality of vanes 31 are arranged inside the inlet horn 30.

The vanes 31 have a corrugated structure and extend over at least a portion of the length of the inlet horn 30.

The vanes may be of different lengths and may be composed of several segments.

Inlet horn 30 preferably extends about 1/4 to 3/4 of the circumference of steam stripper 28.

An inlet horn 30 is positioned within the steam stripper 28 so that centrifugal motion is imparted to the mixture as it passes therethrough.

Centrifugal motion increases the forces acting on the mixture.

The corrugated surfaces of the vanes 310 utilize the forces imparted by centrifugal motion to create turbulence within the mixture as it passes through the inlet horn 30.

This turbulence causes coalescence or recombination of a substantial portion of the fine particle size asphaltenes and resin with the liquid asphaltenes and resin.

The inlet horn 30 is provided with a downward slope to provide a downward force on the mixture in addition to gravity, thereby directing the liquid portion of the mixture to the lowest portion of the steam stripper 28. desirable.

The mixture passes through the inlet horn via conduit 24 and flows outwardly and preferably downwardly from the central axis of the steam stripper 28 such that the interior walls of the steam stripper absorb the liquid contained in the mixture. completely wetted by asphaltene and resin.

Although the exact mechanism is currently unknown, the recombination of fine-grained asphaltenes and resins is likely due to the action of turbulence created by taking advantage of the motive force imparted to the fine-grained materials as a result of centrifugal motion. It is considered that there is.

The turbulence causes the fine particles to impinge or impinge on the wetted surface of the inlet horn 30 and then coalesce with or adhere to the liquid asphaltenes and resins present on the surface.

This recombination is also due to the previously mentioned factors and the high shear rates and strong It should also be possible to obtain this effect in combination with the friction effect.

Surprisingly, it has been found that increased turbulence within the mixture inside the inlet horn 30 does not exacerbate the problem of droplet entrainment due to vortices that occur as the mixture enters the steam stripper.

The presence of the vanes 31 in the inlet horn 30 significantly increases the amount of fines removed from the vaporized solvent compared to conventional tangential introduction with three sidewall configurations.

The overall effect of this means of introduction is such that the generally more turbulent flow of the mixture into the steam stripper slightly increases the problem of droplet entrainment, but is sufficient to overcome the increased problem of droplet entrainment. It is effective for

Referring now to FIG. 3, which shows another preferred embodiment of the invention.

In this embodiment, the inlet horn 30 is positioned such that the mixture is introduced from the conduit 24 into the steam stripper 28 tangentially to the curved inner wall of the steam stripper 28 .

The liquid asphaltenes and resin wet the interior surfaces of the inlet horn, then flow down the interior walls of the steam stripper and collect in the lower portion of the steam stripper.

Steam is introduced into the lower portion of steam stripper 28 through conduit 34 (see FIG. 1).

This water vapor vaporizes any remaining solvent combined with the liquid asphaltenes and resin.

The vaporized solvent and water vapor rise through the central portion of the water vapor stripper 28 in countercurrent fashion to the liquid asphaltenes and resin flowing down the inner walls of the stripper.

This allows the liquid substance to be preheated by the rising steam, while also partially cooling the vaporized solvent and water vapor.

Vaporized solvent and water vapor are removed from the water vapor stripper 28 via conduit 36 and introduced into a solvent condenser 38.

Liquid asphaltenes and resin are removed from the steam stripper 28 via conduit 48 and recovered as a heavy phase product.

In the lower part of the steam stripper 28 there are several contact trays 32, e.g. with bubble caps 60.
, or any other type of tray (see Figure 3).

As the liquid asphaltene and resin flow down the inner wall of the stripper 28, they pass through the surface of the tray 32 and eventually collect at the bottom of the steam stripper 28.

Water vapor is introduced into the stripper 28 below the lowest tray, rises through the stripper, contacts the liquid asphaltenes and resin, and vaporizes at least a portion of any residual solvent.

The vaporized solvent and water vapor rise through the inner center of the water vapor stripper 28.

In operation, the flow rate of the first heavy phase to the steam stripper 28 is the same as that of the first separation zone 1.
8 by a liquid level controller (not shown).

The liquid level controller includes a first liquid level controller inside the first separation zone 18.
It is connected to a suitable sensor in the first separation zone 18, which is capable of measuring the amount of heavy phase.

The information provided by the sensor is analyzed by a liquid level controller and then an automatic valve (
(not shown) are operated to increase or decrease the amount of the first heavy phase from the first separation zone 18, respectively, in response to opening and closing of the valves.

The liquid level of the liquid asphaltene and resin in the bottom of the steam stripper 28 is regulated by a liquid level controller (not shown) that can actuate an automatic valve (not shown) provided in the middle of the conduit 48. .

This liquid level controller is coupled to a suitable sensor in the lower portion of the steam stripper 28 that can measure the amount of asphaltene and resin within the steam stripper 28.

Information from the sensor is analyzed by a liquid level controller and actuation of valves regulates the rate of discharge of asphaltene and resin from conduit 48.

If within the lower portion of the steam stripper 28,
If it is determined that the liquid level of asphaltene and resin is high,
The liquid level controller opens the valve to drain.

If the amount of asphaltene and resin contained in the steam stripper 28 is insufficient, so that the solvent is
As such, the valves are at least partially closed to restrict the flow of asphaltenes and resin until the desired amount has accumulated within the steam stripper 28.

A liquid level controller with the above-mentioned adjustment function is
Those skilled in the art are well aware of the
1sherControls Company)
It is commercially available from -.

The explanation will be given by returning to FIG. 1 again.

The vaporized solvent and water vapor condense in a solvent condenser 38 into a liquid mixture substantially free of asphaltenes of any fine particle size.

This results in asphaltene carryover from the steam stripper 28 due to the practice of the present invention.
ry −over ')fr' due to being eliminated or substantially minimized.

The liquid mixture is removed from the solvent condenser 38 through conduit 40 and introduced into a solvent surge tank 42 with a drainage system.

In the surge tank 42, the solvent is separated from the water using differences in liquid density, removed via conduit 44, and recycled into the process.

Water, which has a greater density than the solvent, is removed from a drain at the bottom of the surge tank 42 through a conduit 46 and disposed of by draining or in a suitable manner.

The separated first light phase consisting of oil and solvent is removed from the first separation zone 18 through conduit 20 and introduced into the second separation zone 22 .

In one particular embodiment, the temperature level of the second separation zone 22 is maintained higher than the temperature level of the first separation zone 18;
An elevated pressure is also maintained, thereby separating the first light phase into a second light phase consisting of the solvent and a liquid second heavy phase consisting of oil and some solvent.

A second light phase of solvent is removed from the second separation zone 22 through conduit 50 and recycled through the process.

The second heavy phase is removed from conduit 52 for recovery or additional processing.

More specifically, the second separation zone 22 is the first separation zone 1
Maintain the temperature within the range of about 20'F above the temperature level of 8 to above the critical temperature of the solvent.

The pressure level in the second separation zone 22 is kept at least equal to the vapor pressure of the solvent if zone 22 is kept below the critical temperature of the solvent, and when equal to or above the critical temperature of the solvent. , kept at least equal to the critical pressure of the solvent.

The pressure level in the second separation zone 22 may be maintained at substantially the same pressure level as in the first separation zone 18.

In another embodiment, which can also be shown in FIG.
Feedstock and solvent are introduced into first separation zone 18 as described above.

In this case, the temperature and pressure levels of the first separation zone 18 are adjusted so that the feed condensates are separated into a first light phase containing oil, resin and solvent and a first heavy phase containing asphaltenes and some solvent. and maintained at a determined level so that they are separated from each other.

The first heavy phase is removed from the first separation zone 18 through conduit 24 and treated as described above to reduce the pressure and recombine any fine particle size asphaltenes dispersed in the vaporized solvent. .

The first light phase is removed from the first separation zone 18 through conduit 20 and introduced into the second separation zone 22 .

The second separation zone 22 has temperature and pressure levels determined to separate the first light phase into a second light phase consisting of a solvent and a second heavy phase consisting of oil, resin and some solvent. Keep it.

The temperature level in the second separation zone 22 is preferably kept above the critical temperature of the solvent.

A second light phase of solvent is removed from the second separation zone 22 through conduit 50 and recycled.

The second heavy phase is removed from the second separation zone 22 through conduit 52 as described above.

In this example, a pressure reducing valve 54 is provided in the middle of the conduit 52 to reduce the pressure of the second heavy phase.

It is desirable to reduce the pressure level of the second heavy phase to about 0 to 50 psig.

Due to the reduced pressure treatment, a substantial portion of the solvent contained in the second heavy phase is vaporized.

However, a small amount of solvent is left behind.

Unfortunately, the vacuum or flash process also creates undesirable fock or atomized mist of fine particle size resins and oils.

These particles are dispersed in the vaporized solvent and do not readily recombine with liquid resins and oils.

Fine particle size resins and oils contained in the vaporized solvent were observed to solidify as the solvent was condensed for recirculation within the process.

The solidified particles settle inside the solvent condensation device and subsequent devices.

The settled particles accumulate in the equipment and eventually block the discharge conduit and disrupt the bitumen separation process.

In accordance with the present invention, the vaporized solvent, fine particle size resin and oil, and liquid resin and oil mixture in conduit 52 passes through an inlet horn that is identical in construction to inlet horn 30 in stripper 28 described above; It is introduced into a steam stripper 58.

Water vapor is introduced from conduit 62 into the lower portion of stripper 58 .

The mixture is separated and the solvent is stripped from the liquid resin and oil as it was separated from the liquid asphaltene and resin in the stripper 28 .

The resin and oil settle through the apparatus and collect at the bottom of the steam stripper 58.

Resin and oil are transferred to the stripper 58 via conduit 64.
Remove it from the bottom and collect it.

The vaporized solvent and water vapor are removed from the stripper 58 through conduit 66, introduced into a solvent condenser, and ultimately recycled through the process.

Advantageously, conduit 66 and conduit 36 are connected to combine the vaporized solvent and water vapor from stripper 58 with the vaporized solvent and water vapor from stripper 28 and to introduce the vaporized solvent and water vapor into solvent condensation device 38 . can.

After condensing the solvent by operating the solvent condensing device 38 as described above, the solvent is separated from the condensed water in the solvent surge tank 42 and then recirculated within the process.

In yet another embodiment of the invention, as shown in FIG. 4, the atmospheric distillation residue feedstock is separated into three separate products, each consisting of an asphaltene, a resin, and an oil.

In this embodiment, the raw material atmospheric distillation residue oil is transferred to the conduit 110.
into the upper part 112 of the first separation zone 118.

A solvent introduced into the lower portion 116 of the first separation zone 118 from conduit 114 contacts the feedstock.

By maintaining the first separation zone 118 at an elevated temperature and pressure, the feedstock-solvent mixture is separated into a first light phase containing resin, oil and solvent and a first heavy phase containing asphaltenes and some solvent. Separates into phases.

Specific conditions for temperature and pressure are selected to provide a solvent density in the first separation zone 118 such that the liquid heavy phase undergoes separation from the remaining solvent-enriched light phase.

More specifically, the first separation zone 118 is approximately 150"F
The temperature is maintained at a level above the critical temperature of the solvent.

The pressure level in the first separation zone 118 is maintained at least equal to the vapor pressure of the solvent, provided that the zone 118 is maintained at a temperature below the critical temperature of the solvent, and equal to or equal to the critical temperature of the solvent;
or higher, at least equal to the critical pressure of the solvent.

The first heavy phase passes through conduit 124 to first separation zone 118
The pressure is reduced through a pressure reducing valve 126 provided in the middle of the conduit 124.

It is desirable to reduce the pressure level of the first heavy phase to about 0 to 50 psig.

Due to the reduced pressure, a substantial portion of the solvent contained in the first heavy phase is vaporized, but a small amount of the solvent remains dissolved in the liquid asphaltene.

Unfortunately, vacuum processing also forms a fine particle size fock or atomized mist that is dispersed in the vaporized solvent.

The mixture of vaporized solvent, fine particle size asphaltene, and liquid asphaltene is then transferred to the inlet hole 730 of the stripper 28 (see FIGS. 1-3).
The water vapor is introduced into the water vapor stripper 128 through an inlet horn having the same structure as .

The water vapor is transferred to the water vapor stripper 12 via a conduit 134.
8, and the residual solvent remaining together with the asphaltenes is vaporized.

The liquid asphaltene settles and is removed by water vapor stripper 1.
It gathers in the lower part of 28.

The asphaltenes are removed from the steam stripper 128 through conduit 148 and recovered as an asphaltene product.

The mixture of vaporized solvent and steam is removed from the steam stripper 128 through conduit 136 and transferred to the solvent condenser 13.
8 will be introduced.

The vaporized solvent and water vapor condense into a liquid mixture substantially free of all fine particle size asphaltenes.

The liquid mixture is then passed through conduit 140 to solvent condenser 13
Solvent surge tank 14 taken out from 8 and equipped with water drain 146
Introduced in 2.

The solvent is then recycled into the process through conduit 144.

The first light phase formed in first separation zone 118 is removed via conduit 120 and introduced into second separation zone 122 .

In the second separation zone 122, by adjusting the temperature and pressure in the zone 122, a first light phase is separated into a second light phase consisting of oil and solvent and a second heavy phase consisting of resin and some solvent. separate.

More specifically, the second separation zone 122 is maintained at a higher temperature level than the temperature level in the first separation zone 118.

The pressure level in the second separation zone 122 is maintained at least equal to the vapor pressure of the solvent when the zone 122 is maintained below the critical temperature of the solvent, and is equal to or greater than the critical temperature of the solvent. When maintained, it is maintained at least equal to the critical pressure of the solvent.

The second heavy phase is passed through conduit 152 to second separation zone 122.
The pressure is reduced through a pressure reducing valve 154 provided in the middle of the conduit 152.

By treating the second heavy phase under reduced pressure, at least a portion of the solvent contained in the second heavy phase is vaporized.

If the depressurization of the second heavy phase forms fine particle size resin in the vaporized solvent, the same structure as the inlet horn 30 (see FIGS. 1-3) in the steam stripper 28 described above will be used. A mixture of vaporized solvent, fine particle size resin, and liquid resin is introduced into the steam stripper 156 through an inlet horn having an inlet horn for particle removal and solvent recovery.

Water vapor stripper 15 through water vapor +1 conduit 176
6 to vaporize any remaining solvent together with the resin.

The resin is collected in the lower portion of the steam stripper 156.

The resin is then removed from conduit 158 and recovered as a resin product.

If the mixture does not include fine particle size resin, the mixture in conduit 152 can be introduced into any conventional steam stripper to separate residual solvent from the resin product.

Vaporized solvent and water vapor are removed from the water vapor stripper 156 through conduit 160 and sent to a solvent condenser 138 for recovery following the condensation process.

It should be understood that the vaporized solvent and water vapor may be introduced into a separate solvent condensation device if desired.

The second light phase generated in the second separation zone 122 is transferred to the conduit 15
0 and introduced into the third separation zone 162.

In the third separation zone 162, by adjusting the temperature and pressure in the zone 162, a third light phase consisting of a solvent and a third heavy phase consisting of oil and some solvent are separated into a second phase.
Allow the light phase to separate.

In one more specific embodiment, the third separation zone 16
2 is maintained at a higher temperature level than the temperature level in the second separation zone 122.

The pressure level in third separation zone 162 is maintained at least equal to the vapor pressure of the solvent when zone 162 is maintained below the critical temperature of the solvent, and is equal to or greater than the critical temperature of the solvent. When the temperature is maintained, Q′!
, kept at least equal to the critical pressure of the solvent.

The third light phase containing solvent is passed through conduit 174 to the third light phase.
Separation zone 162 is also removed and recirculated within the process.

The third heavy phase is passed through conduit 164 to third separation zone 162
The pressure is reduced through a pressure reducing valve 166 provided in the middle of the conduit 164.

By reducing the pressure of the third heavy phase, at least a portion of the solvent contained therein is vaporized.

If the formation of fine particle size oil in the vaporized solvent occurs by reducing the pressure on the third heavy phase, the mixture of vaporized solvent, fine particle size oil, and liquid oil is transferred to the steam stripper 28 described above. Steam is introduced into the stripper 168 through an inlet horn having the same structure as the inlet horn 30 (see FIGS. 1-3) in the interior of the tank for particulate removal and solvent recovery.

Water vapor is passed through conduit 178 to water vapor stripper 168
to vaporize any remaining solvent along with the oil.

Oil is collected in the lower portion of steam stripper 168 and removed through conduit 170 for recovery as an oil product.

Vaporized solvent and water vapor are removed from the water vapor stripper 168 via conduit 172 and transferred to the solvent condenser 138.
for condensation and recovery.

If desired, the vaporized solvent and water vapor may be fed to a separate solvent condensing device.

If the mixture of vaporized solvent and oil does not contain fine particle size oil, the mixture can be introduced into a steam stripper by any conventional method to separate residual solvent from the oil product.

As stated above, any fine particle size asphaltenes, resins, or oils contained in the vaporized solvent separated from the asphaltene, resin, or oil products are
They can be removed from the vaporized solvent prior to solvent condensation, thereby preventing particles from being carried over to subsequent solvent recovery equipment.

Examples will be described below, but these examples are not intended to limit the invention.

Example 1 Three tests were carried out to investigate the effectiveness of the present invention in a bitumen separation process.

The first test used a feedstock consisting of low-pressure crude oil rectifier bottoms, also called atmospheric distillation bottoms, and a solvent consisting of pentane in an amount sufficient to provide a solvent-to-feedstock ratio of 12:1 by volume. , contacting and mixing with the feedstock.

The feed mixture is continuously introduced into a first separation zone maintained at a temperature level below about 430 degrees Celsius and a pressure of about 650 psig.

The feedstock mixture separates into a first light phase consisting of oil and solvent and a first heavy phase consisting of asphaltenes, resin and solvent.

The first heavy phase is continuously removed from the first separation zone and passed through a pressure reducing valve.

The first heavy phase is then introduced at a pressure of about 15 psig approximately in the center of a conventional steam stripper of uniform diameter and above a series of trays.

The heavy phase is introduced radially. Steam at a pressure of 200 psig is introduced below the tray in the lower portion of the steam stripper.

Any residual solvent is stripped from the asphaltenes and resin by steam, and the vaporized solvent and steam are removed and introduced into a solvent condenser.

The solvent and water vapor are condensed and then introduced into a solvent surge tank equipped with a drainage system.

After 8 hours of continuous operation, the solvent surge tank was inspected and found to contain deposits of fine particle size asphaltene and resin.

This sediment layer had accumulated inside the surge tank and partially blocked the drain pipe.

Next, a second test is performed.

In this second test, a tangential weight was created so that the vaporized solvent, mist, and liquid asphaltene and resin mixture were fed tangentially into a groove provided along the entire circumference of the steam stripper. Use the phase inlet.

After cleaning the solvent surge tank, the same operation as in the first test was performed.

After 24 hours of operation, inspect the inside of the solvent surge tank.

It was observed that the solvent surge tank contained a small amount of deposited layers of asphaltene and resin.

Perform the third test.

In this test, a steam stripper 28 with an inlet horn 30 (as shown in FIGS. 2 and 3) is installed in accordance with the method of the present invention.

Clean the solvent surge tank. All conditions are kept the same as the first test.

After 48 hours of continuous operation, inspect the inside of the solvent surge tank.

It is confirmed that no new asphaltene or resin has been deposited in the solvent surge tank.

Example 2 Three tests are carried out to determine the effect of the present invention on the bitumen separation process.

In the first test, the solvent to feed ratio was 12:1 by volume.
A solvent consisting of pentane in an amount sufficient to give a total of 1.0% and a feedstock consisting of an atmospheric distillation residue are contacted and mixed.

The feed mixture is continuously introduced into a first separation zone maintained at a temperature level of about 450'F and a pressure of about 675 psig.

The feed mixture is separated into a first light phase consisting of oil, resin and solvent and a first heavy phase consisting of asphaltenes and solvent.

The first light phase is continuously removed and introduced into the second separation zone.

The second separation zone was heated to a temperature level of 425'F and 650 ps.
ig pressure level.

The first light phase is separated into a second light phase consisting of solvent and a second heavy phase consisting of oil, resin and some solvent.

A second heavy phase is continuously removed from the second separation zone and passed through a pressure reducing valve to reduce the pressure level of the second heavy phase.

A second heavy phase is then introduced above the series of trays approximately in the center of a conventional uniform diameter steam stripper under a pressure of about 15 psig.

The heavy phase is introduced radially into the stripper.

Steam is introduced below the tray of the steam stripper at a pressure of 200 psig.

This steam strips any residual solvent from the oil and resin.

The vaporized solvent and steam are removed from the steam stripper and the solvent and steam are condensed.

The resulting liquid stream is then introduced into a solvent surge tank with drainage equipment.

After 8 hours of continuous operation, the solvent surge tank was inspected and found to contain a resin build-up layer of fine particle size that had accumulated in the tank and partially blocked the drainage conduit.

Next, a second test will be conducted.

In the second test, a tangential heavy phase inlet was constructed so that a mixture of vaporized solvent, mist, and liquid asphaltene was fed tangentially to the groove provided along the entire circumference of the steam stripper. Use.

Clean the solvent surge tank and operate as in the first test.

After 24 hours of continuous operation, it was observed that the solvent surge tank contained a small layer of asphaltene deposits.

A third test is then conducted according to the method of the invention.

In this case, a steam stripper 58 with an inlet horn 30 (as shown in FIGS. 2 and 3) is used.

Clean the solvent surge tank. All conditions are kept the same as the first test.

After 48 hours of continuous operation, inspect the inside of the solvent surge tank.

No new asphaltene deposits were observed in the solvent surge tank.

From the above examples, it is clear that advantages can be obtained by implementing the invention.

According to the invention, continuous operation of the bitumen separation process is made possible by recombining the liquid portion of the separated phase with the fine particle size flakes or mist produced by depressurization of the separated phase.

Further, the recombination can also prevent fine particles from being carried over into the solvent recovery device of the process.

As used herein, the term "bituminous material" refers to pyrogenic bitumen and natural bitumen, one or more fractions or components thereof, oxygen or other oxygen in the presence or absence of a catalyst. It refers to the products obtained by processing these substances, or their components or fractions, with the gases they contain, or by processing these substances in other ways.

Pyrolysis bitumen includes heavy, i.e., petroleum-based crude oil with a very low API gravity, prefixed crude oil treated with either steam distillation or vacuum distillation, hard or soft wood pitch, coal tar residue oil, and cracked tar. , tall oil and others.

Natural bitumen contains gilsonite.
e), wurtzilite, albertite, natural asphalts such as Trinidad asphalt.
phalt) etc. are included.

Suitable catalysts include, for example, phosphorous pentoxide, ferric chloride, cobalt salts, and the like.

As used herein, "treatment by other methods" includes, for example, subjecting an asphalt-type material to a condensation reaction in the presence of a suitable treatment agent to produce a heavier or more complex material.

An example of a suitable treatment agent is a Friedel-Crafts type catalyst.

As used herein, the term "solvent" refers to aromatic hydrocarbons having a normal boiling point of 350"F or less, such as evabenzene, toluene, o-lm- and p-xylene and isopropylbenzene, paraffin having 3 to 9 carbon atoms. hydrocarbons such as propane, butane, pentane, hexane, heptane, octane and nonane, as well as monoolefinic hydrocarbons such as butene, pentene, hexene, heptene and octene, and other related organic compounds such as from 3 to 9 carbon atoms. A fluid consisting of at least one member selected from the group consisting of alcohols, etc.

Although the present invention has been described in terms of its presently preferred embodiments, certain alterations, substitutions, modifications, etc. may be made without departing from the true scope of the invention as defined in the following claims. It will of course be understood that inventions are possible.

[Brief explanation of drawings]

FIG. 1 schematically illustrates the method of the invention, and FIGS. 2 and 3 show two types of constructions for the inlet horn of a bituminous material layer steam stripper,
FIG. 4 schematically shows another embodiment of the method of the present invention. The meanings of reference symbols used in FIGS. 2 and 3 are as follows. 24... Conduit, 28... Stripper, 30... Inlet horn, 31... Vane, 32... Tray, 60... ...bubble cap.

Claims (1)

[Scope of Claims] 1. By keeping a mixture of liquid bituminous material and a solvent under elevated temperature and pressure, in a separation zone, a liquid light phase consisting of at least a part of the bituminous material and a solvent; separation into a liquid heavy phase consisting of the remainder of the bituminous material and a solvent; vaporizing at least a portion of the solvent contained therein by applying a vacuum to at least one of said phases; and vaporizing at least a portion of the solvent contained therein; forming a mixture of liquid bituminous material conjoined with said mixture and undesirable fine particles of bituminous material dispersed therein; A curved introduction means comprising a plurality of vanes containing a plurality of unvaporized solvents is introduced into the steam stripping zone by means of a curved introduction means including a plurality of vanes, and the unvaporized solvent remaining in combination with the liquid bituminous material in a steam stripper tank within the steam stripping zone is introduced into the steam stripping zone. and recovering from the stripping zone a solvent substantially free of bituminous material of fine particle size.2 for at least one of said phases. The depressurization process
1. The method of 1 above, which comprises reducing the pressure of the heavy phase. 3. The method of 2 above, wherein the liquid bituminous material consists of a residual oil containing asphaltenes, resin and oil, and the portion of the liquid bituminous material separated as a heavy phase consists of asphaltenes contained in the residual oil. 4. The method of 2 above, wherein the liquid bituminous material may also be a residual oil containing asphaltenes, resins and oils, and the portion of the liquid bituminous material separated as a heavy phase comprises the asphaltenes and resins contained in the residual oil. 5. The liquid bituminous substance is composed of asphaltenes, resins, residual oils containing oils and solvents, the light phase is composed of oils and solvents, the heavy phase is composed of asphaltenes, resins and some solvents; at least 1
The method of claim 1, wherein the step of depressurizing the phase comprises depressurizing the heavy phase, the bituminous material of the mixture formed comprises asphaltenes and resin, and the fine particles of bituminous material comprise asphaltenes and resin. 6. The method of 1 above, wherein the step of depressurizing one or more of the phases comprises depressurizing a light phase. 7. The liquid bituminous material consists of a residual oil containing asphaltenes, resin and oil, and 8. The method of claim 6, wherein the portion of the liquid bituminous material separated as a phase comprises a resin and an oil. 9. The method of any one of 1 to 8 above, in which the blade has a corrugated structure. 10. The solvent has a normal boiling point of 350'F (176.7°C) or less. Consists of at least one member selected from the group consisting of aromatic hydrocarbons, paraffinic hydrocarbons having 3 to 9 carbon atoms, monorefin hydrocarbons having 4 to 8 carbon atoms, and alcohols having 3 to 9 carbon atoms. 11. The method of any one of 1 to 9 above, wherein the elevated temperature and pressure is
, 6°C) to above the critical temperature of the solvent,
and further defined as a pressure at least equal to the vapor pressure of the solvent when the temperature is below the critical temperature of the solvent, and at least equal to the critical pressure of the solvent when the temperature is equal to or above the critical temperature of the solvent. Method according to any one of 10. 12. The method of any one of claims 1 to 11, wherein the process of introducing the mixture into the stripping zone imparts a generally downward motion to the mixture in addition to the centrifugal motion imparted to the mixture. 13 A mixture of at least two components is introduced into the IJ whelk treatment equipment, and from this mixture at least one type of water vapor that can be vaporized by contact with the water vapor in the IJ whelk treatment equipment is introduced. components (provided that at least a portion of the vaporizable components are such that at least some fine particles of the other non-vaporized components are dispersed therein when the mixture is introduced into the steam stripping device). A steam stripping apparatus for separating (in a vaporized state) a steam stripper 28 and an inlet horn 30, said steam stripper having a conduit having a tangential inlet thereto. 24, and wherein the inlet horn has a curved passageway within the stripper and is connected to the conduit. 14 said passageway is formed by at least three imperforate side walls extending along at least a portion of the inner circumference of said steam stripper 28, said passageway being formed by at least three imperforate side walls extending along at least a portion of the length of said passageway; 13. The apparatus of 13 above, comprising a plurality of arranged wavy blades.