DE1070325B - Method and device for drying adsorbents - Google Patents

Description

FEDERAL REPUBLIC OF GERMAN LA.N O

GERMAN

PATENT OFFICE

KL 23 b 1/05

INTERNAT KL C 10 g

EXPLAINING PAPER 1070 325

S49447IVc / 23b

AN M ELDETAC JULY 11, 1956

NOTICE
THE REGISTRATION
AND ISSUE OF THE
DISPLACEMENT CHARACTER 3 DECEMBER \ 959

The invention relates to a method and a device for drying adsorbents which are used to purify hydrocarbon oils and, after withdrawal from the treatment zone, are treated with a solvent of Hf hydrocarbon to remove still adhering oil, which is then removed again by drying the adsorbent is then fed to a regeneration zone, from which it returns to the treatment zone

The method of the invention consists in that part of the solvent evaporates and, from below flowing upwards, the dryer for the adsorbent passes through in such an amount that in the dryer a fluidized bed is created by the heating of the dryer at a temperature of at least 150 ° C or a temperature above the boiling point of the solvent is maintained, and that also the dried removed from the dryer Adsorbent enters a descent zone, which is an inert gas from the bottom up in such an amount flows through that a fluidized bed is also formed in this zone, with in the Abstreifone maintain a slightly higher pressure than in the dryer wnd, so that the stripping gas together method and apparatus for drying adsorbents

Applicant:

Socony Mobil Oil Company, Inc., New York, N.Y. (V. St. A.)

Representative: Dipl -Ing. W. Meissner, Berlin-Grunewald,

and Dipl -Ing H Tischer, Munich 2, Tal 71,

Patent attorneys

Claimed priority ».

V St ν America of July 11, 1955

Eric Victor Bergstrom, Short Hills, N J (V. St. A), has been named as the inventor

,! with the solvent removed from the absorbent flows into the dryer, from which the evaporated Solvent and the stripping gas are withdrawn together, with the solvent passing through ■ Condensation recovered

The identification is explained below in conjunction with the drawing. It shows
ι Fig 1 a Diagiamm that illustrates the change dei life of the adsorbent as a function of its moisture content.

Fig. 2 cm diagram of a plant for the implementation of a continuous process for the treatment of dimierol according to the invention
¹ Fig. 3 shows an embodiment of the dry ice, fm the adsorption agent,
Fig. 4 shows a vertical section along the line 4-4 in Fig. 3

In the case of the above-mentioned \ it, the usual method consists of the gluey granular admixture then the unwanted impurities never whipped on it in "in a suitable oxygen-depletion factor" atinosphai "/ .ubiennen iy / <> ne abtfe / ogene adsorption agent with ι inei nesintluVun amount of coal wassei slorlol \ οιιμμ · Ιμ im k.mn «s melit diiekl in <he lie» 1 leiimiis ^ om iil »tir <fulii ι widin da then the Π | in this zone \ <ibiiinit wenKii and from <| em S_ \ st (in \ ei Ιοί eng «Ik 11 wind« Vm m.ilei weise is a .suchei Vn lust so yiol). dal) the ς-Λη / Λ procedure

would become completely uneconomical In practice, therefore, as can be seen, for example, from "US Pat. No. 1,70,786, the adsorbent is treated with a washing or solvent of relatively low boiling point that is capable of serving after it has been drained from the treatment zone To loosen the amount of oil adhering to the adsorbent If the treatment process is carried out at a relatively high temperature, for example about 150 to 205 ° C, the adsorbent is usually cooled in a ligendous manner so that no significant amounts of the solvent are evaporated in the washing stage the washing stage next, last with solvent mixed adsorbent then wnd in a Tiocknei passed, the \ ^r orzugsweise works fluidized bed and in the subject the adsorbent a sufficiently high temperature to evaporate the solvent from it the! ietiockiiete adsorbent then passes into Die Reujenei leumgs / .one The fluidization is in (.my fiocknei up to dtiich application i need- (never moth gas for example exhaust gas or nitrogen! or you may be wondering about the use of water vapor. In the practice w 11! written Yei falueii have so far been working in general with water vapor for sounding

As from dei Γ ^ \ -Patentschiift 1 70ί 786 henoi-IJeIi 1, it is important that the moisture content of the * \ ds () i]) tion limit of 1 to 4.5 percent by weight

909 687/384

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and kept 4 percent by weight \ · Ιπ1 Strict <About moisture content in the circulatoryWem /. at some point ubci this value addition, so you · adsorption efficiency drops rapidly and the adsorbent must be replaced at great expense

These relationships are illustrated in FIG. 1, which shows the change in the degree of decolourization efficiency of Fuller's earth from 0.55 to 0.25 mm as an adsorbent, which has gone through 20 cycles of hydration and knihydration, the adsorbent being dehydrated in each cycle. jetted and then hydrated to a certain moisture content. It is clear from the diagram that repeated hydration> 5 to more than 4 ^x h weight percent moisture content causes a rapid drop in the efficiency with which the adsorbent entered the system and leads to a permanently deactivated adsorbent. The division of the diagram was based on the assumption that an adsorbent would be bone dry after heating to 565 ° C a temperature It has now been found that even this does not provide a complete solution to the moisture problem. The adsorbent leaving the washing stage is in almost all cases at a temperature substantially below 150 ° C. In practical operation this current is usually at the temperature of the surrounding atmosphere, which is usually 32 to 38 ° C. It has also been determined that even if the bubbling bed is kept in the dryer at about 175 ° C, the rather cold adsorbent used by the wash zone

first enter the dryer and here -dei-fe-uchtag-

is subject to an atmosphere containing a lot of moisture, immediately sufficient Absorbs moisture so that the maximum value of 4V2 weight percent is exceeded Even if So the fluidized bed in the dryer above the Temperature is maintained at which substantial amounts of moisture are adsorbed adsorption of moisture takes place, as a result of which the above-mentioned undesirable effects occur The use of a readily available inert gas such as Uwa exhaust in place of the commonly used one Water vapor is also not a satisfactory solution, because the exhaust gas is dehydrated in some way had to graze in order to perform an important function, which is an expensive operation

Em main! Purpose of the invention intestines, a vei fahien and a voi 1 icht to see, around the adsorbent between the treatment and! regeneration zones a system for the treatment of liquid oil 111 to bend a condition dei the inadequacy dei bisheiigui Yeifnhiensweise eliminated

TI111 lxsondeiei purpose of the connection is then / λλ S (IiCH a variant and a \ 01 direction, in the \ <lsoiptionMniite! / Between treatment and '■! «• m nei κι unsis / oin eini \ nlnii </ 111 B <handluii'4 λοιι liquid oil in a <'ii condition /.u bring that the moisture content of the adsorptive agent selected you MT treatment effectively and economically kept at the same level, at which the adsorbent agent was quickly de-activated when The above-mentioned purpose of the invention is achieved in that a hydrocarbon solvent is used in the washing stage and a part of this solvent is used after evaporation as an exciter for the fluidized bed in the dryer In particular, it is suitable to be operated with such fluidizing means and also has a groove fluidized bed and steam-working holding chamber next to the drying chamber Part of the Invention In Figure 2 of the drawing is a treatment vessel

10 shown, the upper end by lines

11 fed with a granular adsorbent wild Fuller's earth, Bauxite, bentonite, bone charcoal, charcoal, magnesium silicate, activated by heat and acid Kaolin, active charcoal and synthetic silica, alumina or magnesia gels or synthetic ones Gel combinations from these substances are called The adsorbent is said to be a noticeable Particle shape in contrast /, to fine powder, .have, and the grain size should generally be in the range from 4.7 to 0.15 mm, preferably 1.7 to 0.25 mm, The particles of the Adsorptionsnutteis can be used in regular form, as Balls, grains, pearls, etc., or in irregular shapes such as those obtained by grinding and sieving be obtained, ^

The liquid oil can be treated for various purposes e.g. discoloration, removal of suspended colloidal or dissolved carbon or coke or various gum-forming compounds

The adsorbent runs under the action of gravity as a "column" through the treatment vessel. While it is sinking, the adsorbent can be in a compact state, that is, the individual particles rest on each other and work = always carried by the particles below are a loosened bed have, wherein the particles do not rest on each other, ledoch so enclosed by the surrounding particles that they ^s 'ch in - "' esenthehen rectified vertically downward through the treatment zone move Dei term" column "refers to the two states

Liquid hydrocarbon, for example, a mineral oil odei fuel oil with a low asphalt content, enters the System through line 12 a The oil can optionally The treatment vessel 10 is heated in a V01 warmer 13 before the introduction 111 Suitable treatment temperatures are in the range of -32 to 370 ° C, a typical treatment temperature is about 150 ° C. The oil carried out gets into the lower part of the treatment vessel 10 and then flows upwards duich the sinking adsorbent through, with which the desired cleaning wud wud through the line 14 wud the treated product withdrawn Verbi also adsorbent, the Vei removed from the oil has adsorbed unions, duich sinks the lines 15 together with substantial amounts of oil down from you lead «, η λ ei agree in one ^ .lmmlei 16 / ti a single shorn, dei dutch du Lu tuny 17 goes down Adsoiptionsinitti 1 and Oil then get 111 the focus rieituiig 18, the opposite d (i line 17 has a sufficiently reduced diameter so that the adsorbent in it is suspended in the oil and λ on this get 1 age «wild Adsorbent and oil then go one way

i 070

RoIr ι * 19, a certain hollow is selected in order to set the withdrawal amount of the adsorbent ¹ · αι ·· the treatment vessel 10

Adsorbent and oil now reach one another Line 20 back down into the upper part of the washing vessel 21 This goes through this washing vessel Adsorbent also as a column downwards by Outside the washing vessel becomes a vat held by hydrocarbon solvents in a tank 22. Suitable detergents or solvents are n-heptane, n-octane, and heavy gasoline that boil within a range of 38 to 205 ° C are preferred The solvent is a paraffinic heavy fuel with a boiling range of 93 to 150 ° C. The solvent is drawn from the tank 22 via the line 23 in the lower part of the washing vessel 21 and then guided up through this in order to loosen the liquid oil adhering to the adsorbent, while the unwanted impurities stick to the adsorbent. The washing stage can be at atmospheric Pressure or any other pressure above or below atmospheric pressure and operated at any temperature below the temperature at which a substantial one Evaporation of the solvent takes place, for example at 15 to 120 ° C usually will the solvent in the tank 22 is kept at the ambient temperature, so that the adsorbent is cooled on passage through the washing vessel 21 to a temperature which is very 'close to the temperature of the surrounding area. In any case, the temperature of the adsorbent is when it leaves of the washing vessel well below 175 ° C. The heavy gasoline used with the liquid in the intestine oil leaves the washing vessel through line 24 in a fraction vessel 25 This is where solvents are made and liquid oil separated by distillation The above outgoing solvent passes through line 26 into a condenser 27, where 111 flows back through the tank 22 The liquid ÖJ "will withdrawn from the bottom of the fractionation vessel 25 and combined through line 28 with the fresh oil which Introduced through line 12 in dat. Treatment vessel At the lower end of the washing vessel there is a system similar to that for the solid particles the system on the treatment vessel 10, with adsorbent and solvent through the line Exit 29, then lifted through the delivery line 30 and emerge from this line 30 through one of the tubes 31. The mixture of adsorption so agents and solvents, which are largely based on one Tcmperatui is below 175 ° C, then falls through the Line 32 in the upper part of the dryer 33

F.111 Solvent flow from tank 22 withdrawn through the line 34 and by means of a heating device 35 to a temperature above 150 ° C, for example 230 ° C, heated and • 'ampft The evaporated solvent then disappears > 'en unteien ThI «los Trocknei s 33 a Fs will be one μ ·) aiisu icln-mli amount of evaporated solvent is called / t ihll s, ch the adsorbent ineih.ilb des Ti.ickiui · 1111 state of a fhmiized Pelts there is I'iimih hay winl enough tub • unsuccessful. so dall mine temperatui at least about 150 ° C is kept by ι in indiektei W.timeaustausch mn ι my suitable heating means about steam, take place! dot πι the T3ei7voi iichtung mil iiidnektoi W .mn »iiln 1 transmission through the line felt and dmeh the Leihing 37 dm ans wiedei collected inside the dryer Husmjjc solvent that / usdmnnn with the adsorbent enters, evaporates The dried adsorbent then stiomt from the drying egg 33 in the adjacent Remigungs- or Abieifzone 38 The lower part of this zone 38 is through the line 39 water vapor or another inert Gas supplied in sufficient quantity to absorb the adsorption agent in the stripping zone in the state of a fluidized bed. The temperature in this The stripping zone is kept above 175 ° C continuously The pressure in the stripping zone will be slightly above that Pressure kept in the dry zone so that the stripping gas along with solvent that about is still removed from the adsorbent, flows back into the dryer 33. The total amount of evaporated solvent and stripping gas then withdrawn through line 40 and condensed by condenser 41 before entering tank 22 returns If the stripping gas is condensable, as is the case with water vapor, it can be released from the Tank 22 can be drained intermittently through line 42 as condensate, on the other hand - a non-condensable one If stripping gas is used, it can be vented from tank 22 to the atmosphere, or used elsewhere>; ";} < > ·> «*> ·

-Is lifted to the adsorbent to a level Übeivdejn Regenenerungsgefaß 45; the now existing dried adsorption 'medium is the lower part of a suitable Forderers-44 by a Verschlußsaule'43 in "Example ¹ · as a bucket elevator or gas lift through .. The adsorbent is discharged from the conveyor through the line 46. The main part of the adsorbent reaches the upper part of the regeneration vessel 45, but some of the dried adsorbent is returned through the line 47 to the stripping zone 38, so that that, if for some reason the adsorbent flow to the 3Vockner or between the dryer and scraping chamber is interrupted, the sealing column 43 does not run out and becomes leei but then -from the line 47 is filled with adsorbent Atmosphere escapes or through the conveyor 44 and the lei device 46 got into the regeneration vessel, which would mean an extraordinary fire hazard

In Regenenerungsgefaß 45 the adsorbent falls by gravity down from and is treated with a sauei-containing gas zugefuhit wnd through line 48 and is used for burning off the adsorbed Verunieinigungen The exhaust gas produced by the combustion passes through line 49 from the regenerated adsorbent wnd duich < The line 50 is withdrawn from the regeneration vessel and cooled down in the circuit 51 to the treatment pole. It is then frozen to a level above the treatment vessel 10 by means of the F01-deiois52 and, as a result of welding, the line 53 111 sinks a distribution 75. from which it passes through lines 11 into the treatment vessel

Rs 1 lcirlit eisichtttch dall bu the described star Κι iiu "mile between the treatment vessel and Tiockiiei λot lies on the adsorbent at a Teinpeiatui 111X01 half 150 ⁰ C moisture exposed / t lsi * s (ibsiM rstandbcli is thereby exposed that every - / Solvent used in treatment is rendered anhydrous before it is introduced into the system.

This is carried out in the event that it is necessary to deactivation by moisture in the washing zone to prevent The only point where moisture comes into contact with the adsorbent is the stripping zone 38, but this is where the occurs Adsorbent always at a temperature above 150 ° C and remains at this temperature

Details of a suitable design for the

medium stripped wild, stream through the overflow opening 57 and are withdrawn through line 40 with the main stream of solvent vapor The adsorbent, which is now free of solvent vapor, comes out of zone 60 via a Übereilauf 64 in the zone 61, which is on a slightly lower level than the overflow 57. In the zone 61, the adsorbent sinks than compact masso by gravity down one

The dryer and the stripping zone can be seen from Fig. 3 and 4 io partition plate 65 extends in the chamber 60 m from the walls, which are filled by spaced heating pipes 54 contain these overflows The dividing plate 65 extends These tubes are arranged in bundles, each from a level above the overflow 57 to a bundle of a group of 15 consecutive levels below the overflow 64 to prevent At each end of a bundle of ice, the adsorbent is supplied with a suitable heating medium via the overflow 57, which from the other passes directly to the overflow 64 without the end of the bundle being diverted again is a number of manifolds to be exposed to the dried, a Striped tubes 55 for the vaporized solvent pre-20 adsorbent leaves the zone 61 through those that see the heated solvent vapor through line 43. The adsorbent flow is maintained under line 34 (Fig. 2) The tubes are with
provided a number of openings through which the
Solvent vapor escapes and flows through the drying chamber in order to fluidize the 25
located adsorbent to effect it
can also introduce other institutions
of the solvent vapor. For example, the steam can flow through drip pipes 80

Adsorbents enter, which play main role with bell caps 30 In general, however, it is are provided in order to achieve an even distribution that is desirable for the height of the dryer vessel effect The wet adsorbent will be on a larger than its width dimensions, and further Side of the dryer fed through line 32, it should be sufficiently wide so that the and falls through the funnel 70 into the fiuidisiert, guide 32 not entering adsorbent and eating The surface approximately at the line 56 lies that 35 goes away indirectly via the overflow 57, without topping At the end of the fluidized bed, the next level is reached in the fluidized bed held by an overflow 57, which extends over the As already stated, it is necessary that the

Long one side wall of the drying chamber extends, while the moisture content of the adsorption, which is opposite the side wall, is "aredistically less than 4.5 percent by weight, and the preferred feed 32 for the adsorbent is kept below 4 percent by weight." To meet this requirement, the adsorption run 111 must have the stripping chamber 38, which is connected to the vessel 33
has a common wall across the top
In the middle of the bed and above the heating pipes 54 there is a number of baffle plates 58, which are kept above about 150 ° C for a period of 45 degrees and inclined across the entire width of the drying chamber An adsorbent heated up to 665 ° C as rising vapor must be assumed to be bone dry between these plates

flow, which is the adsorption carried away by the steam. In most operating modes, it is undesirable

deflect medium and cause it to fall into the fiuidized so that the temperature of the adsorbent 230 ° C bed /.uinfallt The vapors then rise to the upper
End of dryer on where the main part of them
reheated by means of a suitable heating means
wild, which flows through pipes 59 to thereby create a

Condensation of the vapor at this point can be distilled to mean 55 In some beti To prevent the steam from being passed through line 40, however, it is possible to use the dryer as a pre

break, the line 43 is released from the return flow 47 supplied with adsorbent, as shown in U.S. Patent 2,709,674

The dimensions of the various parts, the system, obtained by the method of the present invention works depend on a number of factors including the desired throughput and the Nature of the adsorbent to be dried the

medium depart from the drying bed with a temperature of at least 150 ° C and preferably at least 175 ⁰ C, and the stripping zone must Remote Egg

anywhere in the system, apart from \ oin Regeneration vessel, exceeds, because above this Temperature certain adsorbed impurities that are to be burned off from the solution

deducted

The chamber 38 is in an actual drafting zone and a withdrawal or collection chamber 61 below An inert gas, for example, before the lowering zone 60 Steam, introduced at the lower end of the same via distribution pipes 62, by means of heating coils Can hici <hiicli indirect heat exchange tloj M) S) Ieifknmmei also warm / ugefiihit

DtM Diuck in the Aiistrt if / .iine 60 wnd etAvas ubfi ilt'in 65 bum »Him 19 (VC dvuchgefiihit Druck in dei Tiockonzom · i? Ehalt <? N, and« las inert m> i ptionsmittt 1 wiiuk with t'intm Gas wild 111 in such a way as to lidei Meii £ »e supplied that
«'As \ ils () i]) ti (iiiMiiiiit 1 111 (around zone 60 in the nuidisicrten
Condition prevailed with internal gas and solvent vapor. flei through the gas \ 0111 AdsoiptiDiis- 70 bi-n Schwerben / ms was to about 230 ^r C t'ihit / t

To use heater for regeneration vessel In In this case the temperature can be in the dry zone be as high as λ \ κ · 370 ° C

example

With a contimm ι borrowed YeifahuMi / 111 Entcolorunt » \ oii SchmiiMol by means of Fulleu »ide nut i'inei Koinsiiiiisst · \ on J 1 to 0.55mm winde · Enii.11-

l> as benut / .tt \ d Schwei hm / 111 y <wash dav cnicn Su'delxMtich from 105 to 17S ^1-1 C had a choice ι n <l dt s \ Yasch \ 01 gangs became the Vl-I, ml 38 ^C C ahm-lviililt Em part do-Ml-

and \ Erdanipft and your lower part of a dryer of a type similar to that shown in Figs Bauait supplied The temperature in Dryer amounted to about 200 ° C In the adjacent Stripping zone wuide saturated water vapor from about 175 ° C used as a steeling medium

The dryer used was a rectangular jar with 1.57 by 1.52 m cross-section and 3.15 m high heating pipes were over the entire lower section the dry chamber at a level 0.18 m above the ground to a level of 1.97 m Provided distributed above the floor. The overflow edge 57 was 1.07 m from the top of the vessel away, and there was a 0.2 m opening above it Provided over the entire length of the edge. The overflow 57 extended over a length of 1.42 m a 1.52 m side wall of the vessel. The chamber 60 extended along a side wall of the vessel from the upper edge of the opening above the overflow 57 down to a level of 0.84 m below it The overflow 64 was 0.05 m below the overflow 57 and was 0.38 m wide

Of course, details of those described Embodiments of the invention can be changed and improved without the scope of the invention leaving

Claims (4)

Claims 1 Process for drying granular adsorbents used for purifying hydrocarbon oils serve and after withdrawal from the treatment zone to remove still adhering oil with a solvent made of hydrocarbon treated, creating a cooling of the Adsorptionsmtttcls to below 150 ° C which is then dried to evaporate the solvent and finally regenerated is characterized by the fact that "in" is part of the Solvent evaporates and flows from bottom to top through the dryer for the adsorbent passes through in such an amount that a fluidized bed is created in the dryer, which through the heating of the dry ice at one temperature kept at least 150 ° C or a temperature above the boiling point of the solvent is, and that finer the dried adsorbent withdrawn from the dryer in a Stripping zone, which is an inert gas of flows through the bottom upwards in such an amount that a fluidized bed is also created in this zone, with a slightly higher one in the stripping zone Pressure than is maintained in the dryer, so that the dehumidifying gas 7 together with that from the adsorbent removed solvent flows into the dryer, from which the evaporated solvent and the stripping gas are withdrawn together, the solvent being condensed is recovered 2 The method according to claim 1, characterized in that that the solvent is a heavy gasoline with a boiling range of about 38 to 205 ° C serves 3 Vertan ren according to claim 1, characterized in that that superheated steam at a temperature of at least 150 ° C is used as the stripping gas. 4 device for performing the method according to claims 1 to 3, characterized in that that the dryer (33) is on the opposite side of the feed (32) for the adsorbent Side has an overflow (57) on which a stripping chamber is located directly next to the dryer (38) adjoins the common side wall containing the overflow (57) the dryer and is provided with an overflow (64) in the opposite side wall, which is lower than the first-mentioned overflow (57), and that further between the overflows a partition plate (65) is provided spaced from the walls containing the overflows cherishes the length of the shortest of the two Overflows and extends vertically from a level below the second overflow (64) to to a level above the first overflow (57) and that finally next to the stripping chamber a collection chamber is provided, "the adsorbent flowing over the overflow" (64) " records Documents considered
U.S. Patent No. 1,701,786. 2,161,307,830,
German patent specification No. 920 437 Older patents considered
German patent Ni 1 040 724 For this purpose 2 sheets of drawings