CN104321413A

CN104321413A - Cooled annular gas collector

Info

Publication number: CN104321413A
Application number: CN201380024722.4A
Authority: CN
Inventors: O·特纳; F·茹达斯; M·克雷斯; M·库马尔; J·贝特纳
Original assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Current assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Priority date: 2012-05-11
Filing date: 2013-04-12
Publication date: 2015-01-28
Anticipated expiration: 2033-04-12
Also published as: EA027447B1; EA201401239A1; KR20150014909A; ZA201405930B; KR102032589B1; CN104321413B; AU2013258337A1; AU2013258337B2; DE102012009265B4; WO2013167341A1; IN2014MN01843A; UA114197C2; DE102012009265A1

Abstract

In the gasification of carbonaceous solids with oxygen and/or steam in a fixed bed, the reactor (10) operated under pressure must continuously be charged with the solids. These solids are supplied to the fixed bed (12) from a lock via a ring-shaped apron (1) open at the top and at the bottom. This apron (1) includes an inner and an outer jacket, so that a cooling gap is formed with at least one inlet and/or outlet for a cooling medium.

Description

Cold annular gas collector

The present invention relates to the equipment for loading carbonaceous solids in the reactor operated under stress, wherein solid is used oxygen and/or steam gasification in fixed bed, wherein equipment is included in the annular skirtboard of top and bottom opening, solid is fed wherein by lock (lock), in addition, relate to the fixed bed gasification reactor with this equipment, and the method for this reactor of operation.

Gasification should be understood to carbonaceous solids or liquid substance (such as coal, biomass or oil) gasifying medium (oxygen/air, steam) to change into so-called synthetic gas.As main ingredient, this synthetic gas comprises hydrogen (H ₂), water (H ₂o), carbon monoxide (CO), carbonic acid gas (CO ₂) and methane (CH ₄).CO and H ₂it is the initial substance for number of chemical synthesis, based on this initial substance, then can produce more long-chain products, such as gasoline and diesel oil are as so-called CtL fuel (coal liquid), or (SNG=substitute natural gas, for the H of ammonia/fertilizer/urea for other valuable material ₂, methyl alcohol etc.).

But synthetic gas also comprises hydrogen sulfide (H ₂s), carbon oxysulfide (COS), hydrochloric acid (HCl), ammonia (NH ₃), prussic acid (HCN), partially fluorinated hydrogen (HF) and possible higher hydrocarbon and tar.The composition of gas depends on the Dynamic boundary condition of reaction of the kind of the raw material composition that gasification process as selected specifies, gasifying medium used and quality, reaction conditions and existence.

In principle, the solids gasification method that three classes are different is known: gasify in fluidized-bed, gasify in the fixed bed formed by solid, and finally gasifies carrying secretly in bed (entrained bed) reactor.Different gasification technologies applies the different requirements to fuel, correspondingly must consider this point in selection fuel or fuel processing concept.

When actual reactor is designed to fixed-bed reactor, it comprises the substantially cylindrical vertical reactor with outside water jacket.Solid carbonaceous fuels, usual coal or biomass are present in the coal divider of inside reactor from introducing above by lock, form fixed bed there, and it rests on the revolution grate (rotary grate) that is arranged in reactor lower part region.From this lower region, oxygen and steam are blown in fixed bed.

These hot gass flow through fixed bed from bottom to up, and solid by lock system from inserting again above.Therefore, adverse current fixed bed gasification is also mentioned.Because the solid recharged has the temperature of about 40 DEG C, whole fixed bed has such state of temperature, and wherein the hottest part is positioned near revolution grate, and temperature upwards reduces towards solid supply.Corresponding to this state of temperature, carry out different reactions in fixed bed inside.Therefore, usually also mention such reaction zone, there is not the independent district be clearly separated there, but each district is incorporated to each other.Recharging in the gasifier top near solid, carrying out drying and the desorb of the gas of physisorption.So-called reaction zone is positioned at below drying zone, carries out the degasification of solid at an upper portion thereof.Solid after degasification according to the actual gasification of Boudouard reaction and water-gas and water gas shift reaction.In district subsequently, carry out the burning of solid.

The ash particularly obtained between main combustion period descends through a revolution grate step of going forward side by side and discharges therefrom.The unconverted gas fraction of reactant, mainly steam, nitrogen and argon gas take out via the gas conveying end provided more than fixed bed together with the synthetic gas of formation.

Be necessary for the lock system fed by fuel in reactor, because reactor is at 100barg at the most, under the pressure of preferred 60barg at the most, operate particularly preferably under the working pressure of at least 50barg, therefore solid must be introduced under stress.Introduce by lock system and carry out discontinuously, wherein first introduced by fuel in the lock stopped by reactor in atmospheric conditions, then in lock system, pressurization is also inserted in reactor at this pressure.Subsequently again by reactor relative to lock system lock.In order to can still under constant conditions with steady state operation, therefore must provide other solid reservoir at inside reactor, this guarantees that Solid Bed always has identical height.For this reason, known such as from or the various internals of VEB PKM Anlagenbau Leipzig, such as so-called coal divider.Attempted affecting the natural separation of coal particle spectrum by the various design choice of these equipment.Result is only suitable for the gasification realizing improving limited extent.The behavior of particle spectrum Sum decomposition depends on type and the performance of coal very much.

This equipment is such as described in DE 112005002983T5.This is cylindrical or to inner conical (inwardly tapering), namely there is hollow reversion frustum of a cone skirtboard (hollow inversely frustoconical apron) of opening end, it hangs down from reactor head, the coal of discharging from coal lock is moved along skirtboard inside, to be distributed in Solid Bed.The lower end of skirtboard is usually located at fixed bed inside.Between skirtboard and the wall of producer gas generator, form annular gas collecting region, the thick gas collected therefrom is taken out by pneumatic outlet side direction.

In the largest device of operation at present, coal is converted primarily into synthetic gas in fixed bed gasification method, and its middle outlet and reaction terminal temperature on average so low so that gained synthetic gas are taken out at the temperature of 200-300 DEG C (brown coal for humidity) or 400-450 DEG C (for immature hard coal (young hard coal)) from reactor.Medial temperature and the temperature peaks caused by the ununiformity of fixed bed must be distinguished herein.The work-ing life of medial temperature for corrosion and therefore assembly is conclusive.Temperature peaks determines heat and mechanical load, therefore must not exceed ultimate value.

Up to now, the limited value for the equipment gasified at Coal In Fixed Bed must be limited in this wise, so that under the temperature peaks of 650 or 670 DEG C, the power reduction or even stop work of reactor becomes necessary, to limit the thermal load of thick pneumatic outlet.The ature of coal amount of difference or performance and high loading improve amplitude and the frequency of this temperature peaks.

Because fossil feedstock is more and more shorter, solids gasification device must be designed future so that not only by such as wet brown coal or immature hard coal, and can will have other gasification of higher reaction terminal temperature and poorer performance.In addition, the fixed bed gasification of regenerative raw materials or secondary raw material obtains importance, and it mainly has the poorer performance in fixed bed gasification.The temperature herein produced can cause at least 700 DEG C, preferably at the most 800 DEG C, partly the gas outlet temperature of 1000 DEG C even at the most.At these tem-peratures, under skirtboard used is exposed to obviously larger material stress.

In addition, the coal with high-sulfur or content of halogen is vaporization by higher degree.As already mentioned, this causes in gained crude synthesis gas as H ₂the compound of S, COS, HCl and HF.Be positioned at more than conventional temperature so far temperature (such as wet about 250 DEG C, brown coal, prematurity hard coal about 450 DEG C, with older hard coal 450-550 DEG C, compared with hard coal 550-600 DEG C) together, this causes the corrosion that skirtboard place is stronger.In these typical service temperatures, also must increase temperature peaks, it depends on quality and the particle spectrum of coal.Brown coal are greatly disintegrated such as because high fine particle content causes channel (channeling), and this causes CO ₂and temperature peaks.For changing skirtboard, device must be stopped, making production loss occurs.On the other hand, skirtboard use that is so large so that high temperature material can cause cost of investment considerably to improve, and is therefore more uneconomic, because the use of high temperature material only can prevent such as by the corrosion of hydrogen halide limited extent.

Therefore, under the object of the invention is to design the gasification temperature being called that the skirtboard of annular gas collector makes even more than 450 DEG C and/or when using the fuel containing sulphur and/or halogen, the long life of device becomes possible.Meanwhile, frequently temperature peaks must by tolerate and do not impose load and to reduce or the brief or longer-term of reactor is shut down.

According to the present invention, this object feeder according to claim 1 solves.Skirtboard is cooled, for this reason, comprises inner chuck and external jacket, formed therebetween and there is at least one for feeding and discharge the cooling gap of the entrance and exit of heat-eliminating medium.

According to development of the present invention, form Rotational Symmetry, particularly the skirtboard of cylindrical, conical or frustro conical.Columniform advantage is that the fuel introduced by lock system is interspersed among on the whole cross section of fuel bed.In addition, therefore can make the volume maximization of coal feed chute, make with identical packing volume, it has quite short length and effecting reaction device height can not reduce fatefully.But, the coal amount needed for probable error of time between connection two coal latching operations and gasification and charging can be accepted.

When skirtboard chuck is conical, feeder should reduce towards fixed bed.This has from the free export surface of the thick gas of fixed bed advantage large as far as possible.By providing exit surface large as far as possible, the entrainment of each gas velocity and therefore dust can be made to minimize.In addition, gained gas collection space has volume large as far as possible, the velocity of flow of thick gas is also reduced in gas collection space, and improves dust confining force.Finally, exit surface must be designed large as far as possible, make thick gas can flow more uniformly across the whole cross section of fuel bed, and make the Minimizing entrainment of coal particle.Cross-flow should be made to reduce, to guarantee uniform reaction conditions in whole fixed bed.

The part-conical configuration be arranged on cylindrical parts combines the advantage of two kinds of designs.

In ongoing operation, load refrigerant by cooling gap, preferred oiler feed.If use water, water must meet the criterion of vapour generator, in case the deposition of blocking hydrochlorate or boiler scale.In principle, cooling gap must be designed the inlet flow of refrigerant is provided on a limit, and the output stream of refrigerant is on relative edge.But, preferred design cooling gap so as on be liquid impermeable, namely inside and outside chuck connects in liquid closed mode herein.Preferably, this limit, towards fixed bed, is namely arranged in the bottom of reactor.Can be undertaken loading refrigerant in cooling gap by common supply and discharge conduit, or at least one entrance and an outlet are provided.

On the skirtboard limit deviating from fixed bed, namely in upper edge, cooling gap is closed by preferred ring cover, wherein provides a large amount of opening to introduce and to discharge heat-eliminating medium.Then heat-eliminating medium can be introduced in cooling gap on the whole periphery of skirtboard.When being heated by the hot synthesis gas rising through skirtboard outside as water by heat-eliminating medium, it evaporates and rises to top, is overflowed in vapour form by the opening of lid from cooling gap.

Preferably, inside and outside chuck is parallel to be extended, because therefore equipment can easily manufacture, and gained cooling gap has identical width at each point.In an identical manner, can easily form cooling gap herein to make along the volumetric flow of gas of skirtboard and heat therefore to be dissipated those some places extra high, the point that it has than seldom crossing has larger width.Such as, large load is stood in the face of the region of pneumatic outlet.Therefore, can guarantee that in fact whole skirtboard cools fully.

Of the present invention particularly preferably in, next door (bulkhead) is provided between the inside and external jacket of skirtboard, its be preferably parallel to inside and outside chuck extend, to use cooling fluid uniform filling.By next door, form inside and outside cooling gap, it, at least on a point, is preferably interconnected on the whole periphery of skirtboard.

Connection between inner and exterior cooling gap especially easily realizes, because next door provides freeboard with being connected between inner chuck and the jacket portion of external jacket, namely next door does not extend downwardly into the bottom of skirtboard.With this design, can realize refrigerant and flow through skirtboard and do not need pump: the external jacket of exterior cooling recessed bond ing skirtboard, itself and gas collection space directly contact and under being exposed to the temperature of hot crude synthesis gas of rising, it are correspondingly heated.By inner chuck, the refrigerant in internal cooling gap is connected with the solid that recharges of the temperature only with about 40 DEG C.Under therefore refrigerant in exterior cooling gap is exposed to obviously higher than refrigerant in internal cooling gap heat trnasfer, make because convection current generation is by the oriented flow of cooling gap.

Now when water is used as cooling fluid, the boiling point of water is positioned at below the temperature of hot crude synthesis gas.This is also the situation (30bara: boiling point 234 DEG C of cooling system when operating under stress; 51bara:265 DEG C).Gained steam always upwards flows into outlet.In particularly preferred, refrigerant fed in internal cooling gap and to take out from exterior cooling gap.Therefore, the water coolant introduced by internal cooling gap is by contacting and mild heat with next door, and this heat is upwards entered recharge in solid in skirtboard inside, this even causes to small degree the reduction of temperature of cooling water, then enters in exterior cooling gap.Owing to contacting with the hot external jacket of skirtboard, water evaporates there, therefore heat is taken out from system.Gained steam flows out from the vapour outlet provided outside cooling gap.Due to the effusion of steam, new continuous cooling water ground is delivered to exterior cooling gap from internal cooling gap.Within the system, the inside and outside cooling gap therefore transverse shifting (traverse) by natural convection.Natural convection is limited by the density difference of the water column in entrance with the steam-water column in outlet.This produces and produces the so-called cycle number with the business of water cycle as steam, and this is limited by the given geometric pressure-losses.When with the vertical stratification of reactor, the inlet flow of water coolant and output stream are when the upper edge of skirtboard is carried out, and equipment operates especially effectively.

Preferably, design next door, to make internal cooling gap, there is the width less than exterior cooling gap.This provides the advantage of the enough volumes in exterior cooling gap at use water as having gained steam during refrigerant.Therefore, the optimum cycle number of water/steam can be made to be called and also may can to make minimise loss of pressure.

Theme of the present invention is in addition for reactor oxygen and the steam gasification of the feature by carbonaceous solids claim 7.This reactor is included in the revolution grate of bottom appendix and locks at the solid of reactor head, is thereafter above-mentioned skirtboard.

Advantageously, forming reactions device is connected with the cooling system of reactor itself to make the entrance of the cooling gap of skirtboard and/or outlet.This has the following advantages: be cooling skirtboard, need not install cooling loop separately and therefore can reduce cost of capital, in addition, improve reliability and the processing safety of cooling system.Preferably, reactor itself also has cooling jacket, and the cooling jacket of skirtboard is incorporated in described cooling jacket.

In addition, skirtboard and reactor are preferably welded to each other.This becomes possibility, because by cooling apparatus, the temperature of inside and outside chuck can obviously reduce compared with uncooled skirtboard.When the water of below 51bara is used as cooling fluid, boiling temperature is about 265 DEG C, is therefore obviously positioned at below the critical temperature that day by day occurs thus 300 DEG C that the hot gas of carbon steel corrodes.Because cooling protection skirtboard is with protection against corrosion, but also prevent the corrosion that causes because coal moves down, no longer must regularly displacement it, make the expensive connection removed be no longer necessary.

Finally, thought of the present invention also extends to method carbonaceous solids gasified with oxygen and steam of the feature with claim 10.Gasification is carried out in fixed bed, is wherein introduced in batches in the fixed bed of reactor, then continually by feeder of the present invention via lock by solid.Heat-eliminating medium is introduced in liquid form in chuck and is also taken out in vapour form at least in part.By this cooling, can proterctive equipment be with protection against corrosion effectively, can carry out the slight initial cooling to hot crude synthesis gas, also load is less to make assembly subsequently simultaneously.

When take out steam can be used as reactant/gasifying medium advantageously re-use in method inside time, this cooling is advantageous particularly.In fixed bed gasification, steam serves as " conditioning agent ", makes coal ash not melting to limit temperature of combustion.Steam must excessively add.

When water is used as cooling fluid and the water coolant itself taken out in vapour form can be used as reactant, namely in fixed bed by the vapour stream needed for solids gasification partly with the steam produced in cooling for fashionable, the use certificate of steam makes a clear distinction between right and wrong often particularly advantageous.Can reduce the steam demand of method thus, this reduces running cost.When reactor itself also comprises water-cooling jacket and also forms steam there, about 20 volume % of required total quantity of steam save by the steam recycle collected from all cooling modules.

Further feature of the present invention, advantage and may applying also can obtain from following the description of typical embodiments and figure.All features itself described or set forth or be combined to form theme of the present invention with any, and do not depend on whether they are included in claim or its back-reference.

In the drawings:

Fig. 1 schematically shows the fixed-bed reactor of counter-current operation,

Fig. 2 shows annular gas collector of the present invention,

Fig. 3 shows the lid of annular gas collector of the present invention.

Fig. 1 schematically shows reactor 10.It is the vertical fixed-bed reactor of counter-current operation, and it is included in the revolution grate 11 near bottom.On this revolution grate 11, form Solid Bed 12 in operation.By material feeder 13, by steam and/or oxygen-containing medium as air, oxygen-rich air or and purity oxygen from introducing evenly distributedly below and injecting bed 12.The ash formed by the reaction in fixed bed 12 is discharged by revolution grate 11 and is removed via the grey conveying end 14 with ash lock subsequently.Reactor 10 is water-cooleds, and is included in the cooling gap 17 (Fig. 2) between external jacket 18 and inner chuck 19.

Reactor 10 provides lock 20, feeds coal or other carbonaceous solids by it.Be the skirtboard 30 shown in Fig. 2 after lock 20, it is used as solid reservoir, make the fixed bed 12 in reactor 10 have even and enough fill levels, but the loading of coal is carried out discontinuously by locking 20.Fixed bed 12 provides the freeboard around skirtboard 30, wherein collects reactant gases and untapped steam.The gas collected in this gas collection space 15 takes out via gas conveying end 16.

Fig. 2 schematically and show the right half part of feeder 1 of the present invention with cross section.Gas conveying end 16 mainly only provides on one side of reactor.

Feeder 1 comprises double-walled skirtboard 30, and it has inner chuck 31 and external jacket 32, forms cooling gap 33 therebetween.In the lower end of the skirtboard 30 in the face of fixed bed 12, inner chuck 31 is connected in liquid closed mode by jacket portion 35 with external jacket 32.Inner at skirtboard 30, between inner chuck 31 and external jacket 32, provide next door 34.The cooling gap 33 formed between inner chuck 31 and external jacket 32 is divided into internal cooling gap 33i and exterior cooling gap 33a by this next door 34.In ongoing operation, internal cooling gap 33i connects the solid be retained in skirtboard 30 by inner chuck 31, and exterior cooling gap 33a connects gas collection space 15 and fixed bed 12 by external jacket 32.

Next door 34 provides freeboard 36 with being connected between inner chuck 31 and the jacket portion 35 of external jacket 32, and internal cooling gap 33i and exterior cooling gap 33a is connected to each other by described freeboard in the lower end of skirtboard 30.

The cooling fluid of preferably water is introduced between next door 34 and inner chuck 31, flowed downward by gravity and with cold coal (the about 40 DEG C) heat exchange provided in skirtboard inside.Because next door 34 stops rinsing without jacket portion 35, water can enter in the 33a of exterior cooling gap in the lower edge of skirtboard 30.In external jacket 32, the hot gas direct heat exchange in cooling fluid and gas collection space 15.Due to 700 DEG C at the most, the preferably gas temperature of 800 DEG C at the most, heats water to respective boiling temperature (under the working pressure of 51bara about 265 DEG C) and evaporates.Due to its significantly lower density, steam upwards rises (convection current) and can take out in the upper end of cooling gap 33a in outside cooling gap 33a.The surface temperature of external jacket 32 can than temperature of cooling water height 30 ° at the most (depending on gas temperature and load), because heat trnasfer is high on gas side.At external jacket 32 place, still obtain slightly lower than the temperature of 300 DEG C, this is obviously in the uncolled annular gas collector being substantially equivalent to gas temperature below gained temperature.Can avoid or at least greatly reduce the hot gas corrosion of carbon steel.

When reactor 10 itself also comprises water-cooling jacket, the cooling gap 33 of skirtboard 30 preferably and the cooling system of reactor 10, makes the water coolant of the cooling gap 17 between the external jacket 18 of autoreactor 10 and inner chuck 19 also to can be used for loading in the cooling gap 33 of skirtboard 30 to connect.

Fig. 3 display is arranged on feeder 1, preferred weld ring cover 40 thereon, represents the inlet flow of refrigerant and output stream and the connection on reactor 10 simultaneously.

There is provided circular open 41 at the center of lid 40, solid enters feeder 1 from lock system 20 by described opening.Externally skew associating with the chuck of skirtboard 30, concentric(al) circles provides two row of openings 42,43, to be introduced by refrigerant in the 33i of internal cooling gap respectively and take out from the 33a of exterior cooling gap by described opening.By periphery projection (projection) 44, lid 40 can be connected, such as, be welded on (see Fig. 2) on the inside chuck 19 of reactor 10.

In the cold annular gas collector of the present invention, because coal is constantly greatly reduced by lower wall temperature by the inside jacket wear caused, extend possible work-ing life thus.Due to lower temperature, avoid or significantly reduce the hot gas corrosion in external jacket, and do not depend on the concentration of corrosive component in thick gas.Corrosive component in thick gas forms decision by coal.

In addition, gas slightly cools at the external jacket place of annular gas collector, and this produces the lower temperature load in device section subsequently.By at annular gas collector cooling gas, heat to be taken out and by refrigerant evaporates at a point from method.

When water be used as refrigerant time, can subsequently using formed steam as in gasification steam infeed system, the cost of reactant to be fed can be reduced thus.

List of reference numbers:

1 feeder

10 reactors

11 revolution grates

12 fixed beds

The charging of 13 oxygen-containing gass and/or steam

14 grey conveying ends

15 gas collection space

16 gas conveying ends

17 cooling gaps

The external jacket of 18 reactors

The inside chuck of 19 reactors

20 locks

30 skirtboards

31 inner chucks

32 external jacket

33 cooling gaps

33a exterior cooling gap

33i internal cooling gap

34 next doors

35 jacket portion

36 freeboards

40 lids

41 openings

42 openings

43 openings

44 is protruding

Claims

1. for loading the equipment (1) of carbonaceous solids in the reactor operated under stress (10), wherein by solid at fixed bed (12) middle oxygen and/or steam gasification, wherein equipment is included in top and the annular skirtboard (30) at bottom opening, solid is fed wherein by lock (20), it is characterized in that skirtboard (30) comprises inner chuck (31) and external jacket (32), formed therebetween and there is at least one cooling gap (33) for the entrance and/or outlet that provide and discharge heat-eliminating medium.

2. equipment according to claim 1, is characterized in that forming Rotational Symmetry, particularly the skirtboard (30) of cylindrical, conical or frustro conical.

3., according to the equipment of claim 1 or 2, it is characterized in that the inside chuck (31) of skirtboard (30) and external jacket (32) are connected to each other on the downside of the fixed bed (12) in reactor (10).

4. the equipment any one of aforementioned claim, it is characterized in that in the upper edge of the skirtboard (30) in the face of fixed bed (12), the involved multiple opening of cooling gap (33) (42,43) is closed with the lid (40) providing and discharge heat-eliminating medium.

5. the equipment any one of aforementioned claim, it is characterized in that providing next door (34) between the inside chuck (31) and external jacket (32) of skirtboard (30), make to form inside and outside cooling gap (33i, 33a), wherein inside and outside cooling gap (33i, 33a) is at least connected to each other at a point.

6. equipment according to claim 5, is characterized in that inside and outside cooling gap (33i, 33a) is connected to each other on the whole periphery of skirtboard (30).

7., according to the equipment of claim 5 or 6, it is characterized in that next door (34) and freeboard (36) is provided between the jacket portion (35) being connected inner chuck (31) and external jacket (32).

8., for carbonaceous solids being used in fixed bed the reactor (10) of oxygen and/or steam gasification, it comprises the feeder (1) any one of aforementioned claim.

9. reactor according to claim 8, is characterized in that the entrance of the cooling gap (33) of feeder (1) and/or outlet are connected with the cooling gap (17) between external jacket (18) with the inside chuck (19) at reactor (10).

10. by the method for carbonaceous solids oxygen and steam gasification, wherein gasify and to carry out in the fixed-bed reactor operated under stress and solid is introduced in fixed bed by feeder as claimed in one of claims 1-7 via lock, it is characterized in that heat-eliminating medium is introduced in the cooling gap of feeder in liquid form and heat-eliminating medium takes out at least in part in vapour form from cooling gap.