GB2220952A - Apparatus for heating particles - Google Patents
Apparatus for heating particles Download PDFInfo
- Publication number
- GB2220952A GB2220952A GB8817498A GB8817498A GB2220952A GB 2220952 A GB2220952 A GB 2220952A GB 8817498 A GB8817498 A GB 8817498A GB 8817498 A GB8817498 A GB 8817498A GB 2220952 A GB2220952 A GB 2220952A
- Authority
- GB
- United Kingdom
- Prior art keywords
- heat transfer
- series
- compartment
- group
- vessel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
- C10B47/00—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion
- C10B47/18—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion with moving charge
- C10B47/22—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion with moving charge in dispersed form
- C10B47/24—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion with moving charge in dispersed form according to the "fluidised bed" technique
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
- C10B47/00—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion
- C10B47/18—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion with moving charge
- C10B47/26—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion with moving charge with the aid of hot liquids, e.g. molten salts
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Combustion & Propulsion (AREA)
- Materials Engineering (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Chemistry (AREA)
- Dispersion Chemistry (AREA)
- Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
Apparatus for heating particles comprising a heating vessel (1) provided with two series (2, 10) of interconnected compartments, a particle inlet (16) associated with the first compartment (3) of the first series (2), a particle outlet (19) associated with the last compartment (14) of the second series (10), means for introducing fluidizing gas into the compartments and gas outlet means; a cooling vessel (20) provided with two series (22, 30) of interconnected compartments, a particle inlet (36) associated with the first compartment (23) of the first series (22), a particle outlet (39) associated with the last (34) compartment of the second series (30), means for introducing fluidizing gas into the compartments and gas outlet means; a first group of heat transfer loops (50, 51, 52, 53) for transferring heat from a compartment of the first series (22) of the cooling vessel (20) to a compartment of the second series (10) of the heating vessel (1); and a second group of heat transfer loops (61, 62, 63, 64) for transferring heat from a compartment of the second series (30) of the cooling vessel (20) to a compartment of the first series (2) of the heating vessel (1), wherein the heat transfer medium in the first group of heat transfer loops (50, 51, 52, 53) comprises Li2CO3, Na2CO3 and K2CO3, and wherein the heat transfer medium in the second group of heat transfer loops (61, 62, 63, 64) comprises NaNO3 and KNO3. <IMAGE>
Description
APPARATUS FOR HEATING PARTICLES
The present invention relates to an apparatus for heating particles, in particular an apparatus for heating particles of a hydrocarbon-bearing substrate, for example oil shale, tar sand or a bituminous coal in order to extract hydrocarbons from such hydrocarbon-bearing substrate.
Such extraction is carried out at a temperature of at least 400 "C in the substantial absence of oxygen. In the case of oil shale this process is usually called retorting and in the case of bituminous coal this process is usually called pyrolysis.
It is an object of the present invention to provide an apparatus for heating particles which allows efficient heat transfer to the particles in the particular temperature range.
To this end the apparatus for heating particles according to the present invention comprises (a) a heating vessel provided with two series of interconnected compartments, a particle inlet associated with the first compartment of the first series, a particle outlet associated with the last compartment of the second series, means for introducing fluidizing gas into the compartments and gas outlet means; (b) a cooling vessel provided with two series of interconnected compartments, a particle inlet associated with the first compartment of the first series, a particle outlet associated with the last compartment of the second series, means for introducing fluidizing gas into the compartments and gas outlet means;; (c) a first group of heat transfer loops for transferring heat from a compartment of the first series of the cooling vessel to a compartment of the second series of the heating vessel; and (d) a second group of heat transfer loops for transferring heat from a compartment of the second series of the cooling vessel to a compartment of the first series of the heating vessel, wherein the heat transfer medium in the first group of heat transfer loops comprises a mixture of metal carbonates, and wherein the heat transfer medium in the second group of heat transfer loops comprises a mixture of metal nitrates.
The invention will now be described in more detail by way of example with reference to the accompanying drawings, wherein
-Figure 1 shows schematically a top view of a first embodiment of the invention; and
Figure 2 shows schematically a part of the top view of a second embodiment of the invention.
The apparatus for heating particles comprises a first vessel 1 provided with a first series 2 of interconnected compartments 3, 4, 5 and 6, and a second series 10 of interconnected compartments 11, 12, 13 and 14. Associated with the first compartment 3 of the first series 2 is a particle inlet 16 and associated with the last compartment 14 of the second series 10 is a particle outlet 19. The heating vessel 1 is further provided with means (not shown) for introducing fluidizing gas into the compartments arranged in the lower part of each compartment, and gas outlet means (not shown) arranged at the upper parts of the-compartments.
The apparatus for heating particles further comprises a cooling vessel 20 provided with a first series 22 of interconnected compartments 23, 24, 25 and 26, and a second series 30 of interconnected compartments 31, 32, 33 and 34. Associated with the first compartment 23 of the first series 22 is a particle inlet 36 and associated with the last compartment 34 of the second series 30 is a particle outlet 39. The cooling vessel 20 is further provided with means (not shown) for introducing fluidizing gas into the compartments arranged in the lower part of each compartment, and gas outlet means (not shown) arranged at the upper parts of the compartments.
The compartments in the heating vessel 1 and in the cooling vessel 20 are separated from each other by separating means 42 which allow controlled flow of particles from one compartment to the next compartment. For the sake of clarity the reference numerals of only a few separating means have been shown. The separating means can be a weir extending from the lower part of the vessel upwardly, or a baffle extending from the upper part of the vessel downwardly. The weir or the baffle can be provided with openings.
To transfer heat from a compartment of the first series 22 of the cooling vessel 20 to a compartment of the second series 10 of the heating vessel 1, the apparatus comprises a first group of heat transfer loops. The first group of heat transfer loops comprises the heat transfer loops 50, 51, 52 and 53. The heat transfer medium in the first group of heat transfer loops is a mixture of metal carbonates. A suitable composition of the mixture is between 25 and 35 Zw Li2C03, between 25 and 35 %w Na2C03 and between 35 and 45 %w K2C03.
To transfer heat from a compartment of the second series 30 of the cooling vessel 20 to a compartment of the first series 2 of the heating vessel 1, the apparatus comprises a second group of heat transfer loops. The second group of heat transfer loops comprises the heat transfer loops 61, 62, 63 and 64. The heat transfer medium in the second group of heat transfer loops is a mixture of metal nitrates. A suitable composition of the mixture is between 55 and 65 %w NaN03 and between 35 and 45 w KN03.
During normal operation fluidizing gas is supplied to the means for introducing fluidizing gas into the compartments of the heating vessel 1 and of the cooling vessel 20. Shale particles at a temperature between 250 and 370 'C are supplied to the particle inlet 16 of the heating vessel 1. The shale particles move from the first compartment 3 of the heating vessel 1 in the form of a fluidized bed via the separating means 42 into the second 4 compartment and so on into the last compartment 14. In the heating vessel 1 the shale particles are heated as described below so that hydrocarbons are liberated. The liberated hydrocarbons are removed from the vessel 1 through the gas outlet means. The shale particles from which hydrocarbons are liberated are referred to as retorted shale particles.The amount of fluidizing gas introduced into the compartments of the heating vessel 1 is so selected that the total superficial gas velocity at the upper end of the bed is between 0.3 and 1.5 m/s. Retorted shale particles are withdrawn from the heating vessel 1 through particle outlet 19. From there the retorted shale particles are passed to a combustor where coke present on the retorted shale particles is combusted to obtain hot spent shale particles.
At least part of the hot spent shale particles is supplied to the particle inlet 36 of the cooling vessel at a temperature between 750 and 1 000 "C. The shale particles move from the first compartment 23 of the cooling vessel 20 in the form of a fluidized bed via the separating means 42 into the second compartment 24 and so on into the last compartment 34. In the cooling vessel 20 the shale particles are cooled as described below. The amount of fluidizing gas introduced into the compartments of the cooling vessel 20 is so selected that the superficial gas velocity at the upper end of the bed is between 0.1 and 1.5 m/s. Cooled shale particles are withdrawn from the cooling vessel 20 through particle outlet 39.
The shale particles in the first series 2 of interconnected compartments of the heating vessel 1 are heated by means of heat transfer medium circulating through the heat transfer loops 64, 63, 62 and 61 of the second group of heat transfer loops, which heat transfer medium is heated by hot spent shale particles passing through the second series 30 of interconnected compartments of the cooling vessel 20. The shale particles in the second series 10 of interconnected compartments of the heating vessel 1 are heated by means of heat transfer medium circulating through the heat transfer loops 53, 52, 51 and 50 of the first group of heat transfer loops, which heat transfer medium is heated by hot spent shale particles passing through the first series 22 of interconnected compartments of the cooling vessel 20.
In the first series 22 of interconnected compartments of the cooling vessel 20 the hot spent shale is cooled from a temperature between 750 and 1 000 "C to a a temperature between 700 and 800 "C, and in the second series 30 of interconnected compartments of the cooling vessel 20 the hot spent shale is cooled to a temperat;ure between 600 and 700 "C.
In the first series 2 of interconnected compartments of the heating vessel 1 the shale is heated from a temperature between 300 and 350 "C to a a temperature between 400 and 450 "C, and in the second series 10 of interconnected compartments of the heating vessel 1 the shale is heated to a final temperature between 500 and 600 "C.
The minimum melting point of the heat transfer medium circulating in the first group of heat transfer loops 50, 51, 52 and 53 is about 400 "C. The minimum melting point of the heat transfer medium circulating in the second group of heat transfer loops 61, 62, 63 and 64 is about 220 "C.
The composition of the heat transfer medium in each of the two groups of heat transfer loops is so selected that the minimum melting point of the heat transfer medium is just below the lower operating temperature of that group the heat transfer loops.
The area of the heat exchange surfaces of the first group and second group of heat transfer loops in the heating vessel 1 is between 5 and 25 m2/m3 fluidized bed, and the area of the heat exchange surfaces of the first group and second group of heat transfer loops in the cooling vessel 20 is between 5 and 25 m2/m3 fluidized bed.
The area of the heat exchange surface of the second group in the heating vessel 1 is between 0.3 and 0.6 times the area of the heat exchange surface of the first group in the heating vessel 1.
The shale particles supplied to the inlet 16 of the heating vessel 1 are preheated. This is done by heat exchange with the cooled spent shale leaving the cooling vessel 20 in a preheater.
This preheater can be a separate unit or it can be included :n the apparatus of the present invention as shown in Figure 2.
In Figure 2 the preheating vessel is referred to with reference numeral 70. The preheating vessel 70 is provided with a series of interconnected compartments 71, 72 and 73 separated from each other by separation means 42, a particle inlet 76 associated with the first compartment 7i, a particle outlet 78 associated with the last compartment 73 and communicating with the particle inlet 19 of the heating vessel 1, means for introducing fluidizing gas (not shown) into the compartments arranged in the lower part of each compartment, and gas outlet means (not shown).
The apparatus further comprises an after-cooling vessel 80 provided with a series of interconnected compartments 81, 82 and 83 separated from each other by separation means 42, a particle inlet 86 associated with the first compartment 81 and communicating with the particle outlet 39 of the cooling vessel 20, a particle outlet 88 associated with the last compartment 83, means for introducing fluidizing gas (not shown) into the compartments arranged in the lower part of each compartment, and and gas outlet means (not shown) arranged in the upper part of each compartment.
To transfer heat between a compartment of the after-cooling vessel 80 and a compartment of the preheating vessel 70, there is provided a third group of heat transfer loops 91, 92 and 93. The heat transfer medium in the third group of heat transfer loops is a mixture of metal nitrates. A suitable composition of the mixture is between 55 and 65 %w NaNO3 and between 35 and 45 %w KN03. The minimum melting point of this mixture is 220 "C. The heat transfer medium may also be a mixture of between 35 and 45 %w NaNO2, between 50 and 55 %w KN03 and between 3 and 10 w NaN03. The minimum melting point of the latter mixture is about 140 "C.
During normal operation shale particles are supplied to the inlet 76 of the preheating vessel 70 and passes through the compartments 71, 72 and 73 in the form of a fluidized bed. Heated shale is removed from the preheating vessel 70 via outlet 78 and introduced into the heating vessel 1 through inlet 19. There it is treated in the way as described above with reference to Figure 1.
Shale which is cooled in the cooling vessel 20 in the way as described above with reference to Figure 1 is introduced in the after-cooling vessel 80 through inlet 86. The shale passes through the compartments 81, 82 and 83 in the form of a fluidized bed, and is removed from the after-cooling vessel 80 through outlet 88 at a temperature between 550 and 650 "C.
The shale particles in the preheating vessel 70 are heated by means of the heat transfer medium circulating through the heat transfer loops 93, 92 and 91 of the third group.
The area of the heat exchange surface of the third group in the preheating vessel 70 is between 0.2 and 0.4 times the area of the heat exchange surface of the first group in the heating vessel 1.
The apparatus for heating particles as described with reference to the drawings was provided with one cooling vessel, however, in an alternative embodiment the apparatus can be provided with two cooling vessels arranged at either side of the heating vessel, wherein each cooling vessel is provided with two series of interconnected compartments, a particle inlet associated with the first compartment of the first series, a particle outlet associated with the last compartment of the second series, means for introducing fluidizing gas into the compartments and gas outlet means.
In the alternative embodiment the apparatus is provided with a first group of heat transfer loops for transferring heat from a compartment of the first series of each of the two cooling vessels to a compartment of the second series of the heating vessel, and with a second group of heat transfer loops for transferring heat from a compartment of the second series of each of the two cooling vessels to a compartment of the first series of the heating vessel.
The heat transfer media in the two groups of heat transfer loops are similar to the heat transfer media as described above.
The apparatus according to the alternative embodiment can be provided with a preheating vessel associated with one or two after-cooling vessel(s).
Claims (9)
1. Apparatus for heating particles comprising (a) a heating vessel provided with two series of interconnected
compartments, a particle inlet associated with the first
compartment of the first series, a particle outlet associated
with the last compartment of the second series, means for
introducing fluidizing gas into the compartments and gas outlet
means; (b) a cooling vessel provided with two series of interconnected
compartments, a particle inlet associated with the first
compartment of the first series, a particle outlet associated
with the last compartment of the second series, means for
introducing fluidizing gas into the compartments and gas outlet
means; (c) a first group of heat transfer loops for transferring heat from
a compartment of the first series of the cooling vessel to a
compartment of the second series of the heating vessel; and (d) a second group of heat transfer loops for transferring heat
from a compartment of the second series of the cooling vessel
to a compartment of the first series of the heating vessel, wherein the heat transfer medium in the first group of heat transfer loops comprises a mixture of metal carbonates, and wherein the heat transfer medium in the second group of heat transfer loops comprises a mixture of metal nitrates.
2. Apparatus as claimed in claim 1, wherein the area of the heat exchange surfaces of the first group and second group of heat transfer loops in the heating vessel is between 5 and 25 m2/m3 fluidized bed.
3. Apparatus as claimed in claim 1 or 2, wherein the area of the heat exchange surfaces of the first group and second group of heat
transfer loops in the cooling vessel is between 5 and 25 m fluidized bed.
4. Apparatus as claimed in any one of the claims 1-3, wherein the
area of the heat exchange surface of the second group in the heating vessel is between 0.3 and 0.6 times the area of the heat
exchange surface of the first group in the heating vessel.
5. Apparatus as claimed in any one of the claims 1-4, which
further includes a preheating vessel provided with a series of
interconnected compartments, a particle inlet associated with the
first compartment, a particle outlet associated with the last
compartment and communicating with the particle inlet of the
heating vessel, means for introducing fluidizing gas into the
compartments and gas outlet means; an after-cooling vessel provided
with a series of interconnected compartments, a particle inlet
associated with the first compartment and communicating with the
particle outlet of the cooling vessel, a particle outlet associated
with the last compartment, means for introducing fluidizing gas
into the compartments and gas outlet means; and a third group of
heat transfer loops for transferring heat from a compartment of the
after-cooling vessel to a compartment of the preheating vessel,
wherein the heat transfer medium in the third group of heat
transfer loops includes a mixture of metal nitrates.
6. Apparatus as claimed in claim 7, wherein the area of the heat
exchange surface of the third group in the preheating vessel is
between 0.2 and 0.4 times the area of the heat exchange surface of
the first group in the heating vessel.
7. Apparatus as claimed in any one of the claims 1-6, wherein the
heat transfer medium in the first group of heat transfer loops
comprises Li2CO3, Na2CO3 and K2C03, and wherein the heat transfer
medium in the second group of heat transfer loops comprises NaN03
and KN03.
8. Apparatus as claimed in any one of the claims 5-7, wherein the
heat transfer medium in the third group of heat transfer loops
includes NaN03 and In03.
9. Apparatus for heating particles substantially as described in the specification with reference to the accompanying drawings.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8817498A GB2220952A (en) | 1988-07-22 | 1988-07-22 | Apparatus for heating particles |
| CA 605038 CA1332924C (en) | 1988-07-22 | 1989-07-07 | Apparatus for heating particles |
| YU144989A YU144989A (en) | 1988-07-22 | 1989-07-19 | Plant for particles heating |
| CN 89104919 CN1039833A (en) | 1988-07-22 | 1989-07-20 | The device of heating particles |
| BR8903604A BR8903604A (en) | 1988-07-22 | 1989-07-20 | PARTICULATE HEATING APPLIANCE |
| AU38829/89A AU613505B2 (en) | 1988-07-22 | 1989-07-20 | Apparatus for heating particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8817498A GB2220952A (en) | 1988-07-22 | 1988-07-22 | Apparatus for heating particles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8817498D0 GB8817498D0 (en) | 1988-08-24 |
| GB2220952A true GB2220952A (en) | 1990-01-24 |
Family
ID=10640938
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8817498A Withdrawn GB2220952A (en) | 1988-07-22 | 1988-07-22 | Apparatus for heating particles |
Country Status (6)
| Country | Link |
|---|---|
| CN (1) | CN1039833A (en) |
| AU (1) | AU613505B2 (en) |
| BR (1) | BR8903604A (en) |
| CA (1) | CA1332924C (en) |
| GB (1) | GB2220952A (en) |
| YU (1) | YU144989A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104559940B (en) * | 2013-01-01 | 2017-05-24 | 北京工业大学 | Low-melting-point mixed molten salt heat-transferring and heat-storage medium |
| CN104610926B (en) * | 2013-01-01 | 2017-06-16 | 北京工业大学 | A kind of low melting point fused salt mixt heat transfer heat storage medium |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2097018A (en) * | 1981-04-22 | 1982-10-27 | Shell Int Research | Pre-heating particles of a hydrocarbon-bearing substrate |
| GB2097017A (en) * | 1981-04-22 | 1982-10-27 | Shell Int Research | Extraction of hydrocarbons from a hydrocarbon-bearing substrate |
-
1988
- 1988-07-22 GB GB8817498A patent/GB2220952A/en not_active Withdrawn
-
1989
- 1989-07-07 CA CA 605038 patent/CA1332924C/en not_active Expired - Lifetime
- 1989-07-19 YU YU144989A patent/YU144989A/en unknown
- 1989-07-20 CN CN 89104919 patent/CN1039833A/en active Pending
- 1989-07-20 AU AU38829/89A patent/AU613505B2/en not_active Ceased
- 1989-07-20 BR BR8903604A patent/BR8903604A/en unknown
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2097018A (en) * | 1981-04-22 | 1982-10-27 | Shell Int Research | Pre-heating particles of a hydrocarbon-bearing substrate |
| GB2097017A (en) * | 1981-04-22 | 1982-10-27 | Shell Int Research | Extraction of hydrocarbons from a hydrocarbon-bearing substrate |
Also Published As
| Publication number | Publication date |
|---|---|
| CA1332924C (en) | 1994-11-08 |
| YU144989A (en) | 1991-02-28 |
| GB8817498D0 (en) | 1988-08-24 |
| CN1039833A (en) | 1990-02-21 |
| AU3882989A (en) | 1990-01-25 |
| AU613505B2 (en) | 1991-08-01 |
| BR8903604A (en) | 1990-03-13 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |