US2045407A - Distillation of tar - Google Patents

Description

f ,tw fa C E 4 SheetS-Sheefc 2 fonde/75er A. H. RADSCH DISTILLATION 0F TAR 7rc/'a Original Filed July 8, 1931 INVENTOR @24m AW BY ATTORN EYS Finne 23, 1936. A. H. RADAscH 2,045,407

' DISTILLATION OF TAR original Filed July. 8, 1951 @sheets-'sheet s ATTORNEYS .Fume 23,1936. A H, RADASCH 2,045,407

DISTILLATION QF TAR origina-1 Filed Ju1y,. i931 4 sheets-sheet 4 INVENTOR @Mam/@4M ATTORNEYS Patented June 23, 1936 DISTILLATION nOF TAR Arthur H. Radasch, Bloomfield, N. J., assignor to The Barrett Company, New York, N. Y., a corporation of New Jersey Application July 8, 1931, Serial No. 549,419

Renewed January 27,1936

8 Claims.

This invention relates tothe distillation of tar and includes both the process and apparatus therefor. More particularly the invention relates 2o a novel method of recovering tar acids from It is customary to recover the tar acids from tar by distilling the tar, obtainingA a distillate and extracting the condensed distillate or a fraction of the condensedv distillate With caustic lsoda, or other alkaline reagent. This necessitates large tanks for the storage of tar-acid oil and extensive equipment for the liquid extraction. The present method does not require such storage facilities and does provide a continuous process by which .the tar acids are recovered from the vapor phase conjunction with the tar distillation.

There are many advantages in vapor phase extraction of the tar acids as compared with extraction in the liquid phase. By vapor phase extraction I refer to bringing the tar-acid vapors in admixture With vapors of non-acid or neutral oils into contact with an alkaline reagent whereby salts of the tar acids are formed and the tar acids are thus recovered and separated from non-acid constituents Without first condensing them. In order to extract tar acids in the vapor phase without condensing oils the extraction must be carried out without any substantial cooling of the vapors. In order that the extraction may be effected VWith an aqueous solution it is advantageous'thatV the vapors extracted shall not be so hot as to evaporate an excessive amount of Water from the solution because such evaporation will cause crystallization or solidilication of the solute from the solution and will cool `the vapors and cause condensation. Commercial solutions containing about 47 to 50% of caustic can be used in extracting gases or vapors at temperatures up to 200 C. or somewhat higher, without the evaporation of excessive amounts of water.

The temperature of the vapors resulting from distilling the tar may be so high that vapor phase extraction of these vapors is not practicable. Ac-

r ccrding to this invention, therefore, thevapors are cooled in a heavy oil condenser to a temperatureat which they can be extracted with an aqueous solution of an alkaline reagent. Higher boiling oils, including the higher boiling tar acids, are condensed in the cooling process While the lower boiling oils including lower boiling tar acids remain in vapor form. Tar acids are distilled from the condensed heavy oil by passing a large volume of tar-acid-free inert gases through the heavy oil. The gases and vapors from this inert gas distillation are blended with at least a partof the vapors of the lower boiling tar acids and neutral oils that are not condensed with the heavy oil. The blended gases are then extracted VWith an aqueous solution of caustic or other alkaline reagent, which removes tar acids as carbolate and the carbolate so formed includes tar acids that are vaporized from the heavy oil condensate andalso tar acids that are not condensed with the heavy oiljbut remain as vapors after rcondensing the higherboiling oilsV4 Tar acids are thus separated from vapors of non-acid constituents. It isl advantageous to recycle at least a portion of the resulting vapors throughrthe heavy oil condensate to aid in the distillation of tar acids from the heavy oil condensate. The tar-acid distillation is then lselective in so far as vapors of neutral oils in the recycled gases and vapors prevent or inhibit distillation of neutral oils from the heavy-oil condensate. i Y l In this distillationof tar acids from the heavy oil condensate, inert gases such as steamrnay be employed, and at least in part recirculated'. According to apreferred method, howevergthe recirculated gases include vapors of non-acid constituents present in the heavy oil or in the noncondensed vapors from the heavy oil condenser. Gases is used in this application in a broad sense to include non-condensable gasessuch as nitrogen, etc.,which may be employed in the inert gas distillation, and condensable vapors such'as steam and vapors of neutral oils.

If desirable, a condenser maybe employed in the cycle before the gases enter the caustic `tovver and the condenser may be placed in such a position that it acts upon the recycled gases before or after the vapors from the distillation of the heavy oil are blended with the lower boiling vapors from the heavy oil condenser; or a condenser may be included in the cycle for cooling the vapors after they leave the caustic extractor. If the condenser precedes the caustic extractor, tar-acid oils are condensed. If the condenser follows the caustic extractor, the oils may be neutralpoils or oils of at least relatively low tar-acid content.

It may be desirable to treat separately the vapors from the heavy oil condensate with caustic or other'alkaline reagent to recover the tar acids present in this heavy oil condensate before blending these vapors With the vapors leaving the heavy oil condenser. Further, it may be desirable'to insert a condenser in this inert gas cycle after such a caustic extractor toV condense separately neutral oils distilled from the heavy oil condenai before blending the vvapors'from the' distillation of this heavy oil condensate with the vapors leaving the heavy oil condenser.

Various modiiications of the process are possible within the scope of this invention. By condensing and drawing off the heavy oil fraction without excessive cooling, condensate is obtained which generally contains sufcient heat to effect the inert gas distillation of tar acids Tfrom the oil without other heating. Thus the Yentire -heat required for the distillation of tar acids from the heavy oil condensate may be supplied to the tar in the still. Additional heat may be supplied to the system to effect the distillation of tar acids, if necessary or desirable, as, sfor example,

by heating the oil by heat 'interchange with steam or other heating medium before or during the inert gas distillation, or by :heating V.the .'cir'- culated gases, etc. According to the @preferred method, however, the tar acids are vaporized by the self-contained heat of the heavy `oil condensata l "The vrateatwlflich Ftl'ie inert gases are circulated thrcughithe hot condensat-e is correlated with'the temperature of thecondensate so that the desired percentageof the tar 'acids is-vaporized from the condensate. By limiteddistillation, lowerboiling tar acidscan be obtained, such as a mixture of phenol andtheicresols which contains a relatively :small` amount of therv'higher Iboiling acids. By repeated :fractional treatments desired tar-'acid fractions canbe :obtained vfrom the same condensate.

"The vapors from the tar distillation `may be atsuchihigh'temperature that one or more separate .heavy oil fractions maybe condensed before condensing a tar-acid oil fraction containing desired taracids.

"The process-is applicable to the treatment of tars, such fas coke-oven -.tars, gas-retort tars, vertical-retort tars and low-temperature tarsaand other tar-acid vand.neutral-oil-containing hydrocarbon materials `such as coal-tar oils. It may be :applied to 4the treatment of raw, moistureconta-ining taror stripped tar, etc., or Vto the separate -treatment vof tar :fractions such as the heavy :tar'ffrom the collector main of a cokeoveniplant, `or the llighttaror tarr-y oilfrom the condensers ofY such `a plant. It may be applied tofthe treatment of mixtures containing coal tar, etc. The invention will be described more particularly -as .applied to :the .treatment of cokeoven tar.

V In :the Ivapor xph-ase extraction of V.tar acids, caustic lsoda has proven very rsatisfactory, and because-of 'its relative cheapness it is considered a :desirable alkaline reagent for use in this connection. @ther neutralizing agents may `be employed.

:It is advantageous -to-lcarry out `thetar distillation-process 'as a Ycontinuous .process .in which the Yvapors leave the still lat a substantially uniform temperature although the invention may also ibev'applied to a .batch distillation process. When the taris Lcontinuously"distilled apipe still is prefer-red' for 'this purpose although a .tank still `oripot-still `can be employed. A series of stills arranged, forexampla on .thecascade principle, may be employed. The heavy-oil-condenser employed may be used fin conjunction with an ordinaryJfractionatingcolumn. Selected oil :fractions frornrthe rcondensing or fractionating .units maybetreated-.fortherecovery.of graded .tar acid tractions.

`AThe .tar--acidlstill -in rwhich tar acidsare dis tilled from the-heavyoilcondensate .may bea "va-pors from other vapors.

packed tower or a grid tower of the type employed for bringing a gas and liquid into intimate contact, or any other suitable gas and liquid contact apparatus may be used.

The caustic extractors may likewise be packed towers or grid towers or other apparatus containing suitable spray means. Preferably the caustic extractors include more than one Contact chamber in each of which the gases 'are sprayed with caustic for efiiciency in removal of tar acid In order to provide -contactwbetween a large surface of the caustic and the vapors it is advisable to recirculate, with the fresh causticY employed, a part of the carbolate alreadyformed. By providing two or more chambers for the'extraction it is possible to ad- Amitiresh lcaustic to one, recirculate the carbolate 4formed in -it and withdraw carbolate produced in the iinal chamber, as described in connection with thedrawings, without withdrawing any large Apercentage of .uncombined caustic with this finished carbolate.

fAfter the extraction of tar acids from the vapors from the heavy -oil condensation, the vapors may be further cooled and oils condensed either Arractionally .or to .produce a total condensate. These; oils will -be relatively .-free from tar acids, depending upon the thoroughness with which tar acids are removed from the vapors during the tar `acid-extraction. They will include -lower boiling the amount of oil removed vfrom it. If oils are distilled the residuerom the distillation will be aheavy .oil although in some cases it will be a pitch. The invention will be further described in connection with the accompanying drawings but .it .isintende'd and is to be lunderstood that itis not limited thereto. Y

. .-Eig. `1 showsa tar still which includes aheating coil and -vapor box connected with a frac- .tionating column especially equipped for the recovery-.of tarV acids;

IFigs. 2 .to 6 are modified forms of the apparatus shown 1in Fig. 1;

Fig. 7 shows apparatus which may be employed inconnection with a simple still to carry out the invention; and

Fig. 8 shows a series of simple stills arranged for continuous distillation.

In the drawings the same numeral is employed to indicate like apparatus with the addition of a distinguishing letter for each different figure.

lAccording to 'the arrangement of Fig. 1, the tar to be .treate'dis heated in the coil I of the pipe still and vthen flashed in the vapor box v2. The vapors are separated from residue which is drawn oil "into the pitch receiver 3. The vapors pass through the main 4 to the section 5 of the fractionating column. Other sections of the fractionating column are shown at 6 and 1. Between the column sections are cooling coils V8, 8 and 8".

A heavy oil Vfraction is removed from section 5 by cooling the vapors to a temperature such that the oils condensed contain a. negligible amount of tar acids of commercial value. On further cooling oils will be condensed which will contain desirable 'tar acids. From Vsection 6 an oil is withdrawn which `contains -a :part of the desired tar acids and the balance of the desired tar acids pass in .vapor form through the main 9 to the caustic extractor .|0. There is no gas or liquid passage -between the Ycooling coils 8 (above sec- 75 bij tion E) and section 1 of the column. All of the vapors pass from the cooling section above sec,- tion 6 through the main 9 to the caustic extractor I0 and vapors pass from the caustic extractor I0 back to section 1 through the main I0. The vapors enter section at a temperature above that at which they can be extracted in the vapor phase by caustic. They are cooled by the cooling coils above section 6 to about 200 C. or lower and are passed to the caustic tower IIJ at this temperature.

The oil withdrawn from the section 6 throug the line 6 enters the tar-acid still I2, which is` shown as a packed tower in which the oil is brought into intimate contact with inert gases circulated through the linek I I by the blower II These inert gases cause distillation of tar acids from the oil. The tar acids and inert gasespass from the tower` I2 through the main I3 and are combined with the vapors leaving the cooler 8 of the column and are together treated in the caustic extractor I0. In the caustic extractor tar acids are extracted from the vapors and separated as carbolates. If the extraction of tar acids is thorough, the oil obtained by cooling the vapors following such extraction will be a neutral oil.

Apart of the gases from the caustic tower are recirculated through the tower I2. These gases are relatively free from vapors of tar acids, but contain neutral oils which repress further distillation of neutral oils from the heavy oil in the tar-acid still I2, but do not interfere with vaporization of tar acids. The residue drawn off from the tower I2 and collected in the tank I4 will be a neutral oil or oil ofV relatively low tar-acid content. v v

The caustic 'extractor shown is of a preferred type. Fresh `caustic is introduced at I5'. The extractor is divided into two sections, each of which preferably contains grids or other means for exposing a largev surface of liquid to the gases passing through it. In connection with each section a line I6 is provided for withdrawing carbolate which is pumped by pumpsy I'I through the heat interchangers K IB and sprayed into the gases through the spray nozzles I9. Finished carbolate is drawn oif through the'line 20 into the receiver 2I. YThe temperatures of the sprayed solutions are preferably so controlled by the heat interchangers I3 that there is substantially no condensation of oils in the caustic extractor. If desired, the vapors may be cooled to effect condensation of neutralI oils in the caustic extractor.

As an example of a method of operating theapparatus shown in Fig. 1, it is possible to heat coke'- oven tar of about 3% tar-acid content in the coil I to a temperature of 400 C. On flashing, the

v vapors leave the vapor box 2 through the main 4 at a temperature of about 380 C. and pitch with a melting point of about 210 F. is produced. The vapors are cooled in passing through the section 5 to a temperature of about 280 C., and the oil drawn oi of the section 5 through the outlet 5 has a boiling range of about 248 C. to over 400 C. In the section 6 the vapors are cooled to 200 recirculating the inert gases through this oil at a rate of 150 cubic feet per gallon of oil ltreated it is possible to reco-ver in the neighborhood of 80 to 90% of the taracids in the oil.

After extracting the tar acids the vapors are in part` returned to the fractionating column through the line I0', and the balance are recycled through the tar-acid still I2 through the line `I I. By the cooling coils 8 above section 'I of the fractionating column the vapors are further cooled and a neutral oil of lower boiling range is obtained. The vapors are subsequently totally condensed in the final condenser 'I'. Instead of the fractionating column 'I, as shown inFig. 1, the vapors leaving the caustic extractor may pass directly to the final condenser I and be totally condensed.`

f In Fig. 2 the vapors pass directly from the vapor box 2a to the condenser 6a from which the heavy oil condensate is drawn oif to the tar-acid still I2a. The omission of any condenser corresponding to the section 5 and cooling coils vt of Fig. 1 is possible if the tar is distilled to lower melting point pitches. It may even be desirable if high melting point pitch is made, collecting the higher boiling oils together with intermediate boiling tar-acid-containing oils and drawing both off together into the tar-acid still. This gives a larger bulk of oil to be treated in the tar-acid still, but the extra sensible heat content of the higher-boiling oils may at times be an aid to the inert gas distillation. 'Ihe condenser 6a may be an indirect condenser inwhich water or other cooling fluid is circulated through tubes; or part of the condensate may be cooled and recirculated; or any other suitable type of condenser may be used. In Fig. 2 simple condensers are shown for simplicity, and the caustic extractor is shown for simplicity as a single packed tower Illa instead of the preferred extractor shown at IE) inFig. 1.

The apparatus of Fig. 3 includes a condenser 22 between the caustic tower I 0b andthe taracid still I2b. In the apparatus of Fig. 1 there is no direct gas passage between the sections 6 and 'I of the fractionating column. All of the gases from the section 5 pass through the main 9 to the caustic extractor. In Fig. 3 there is an open passage between the sections 6b and 'Ibof the fractionating column. 'I'he main 9h connects with the caustic tower and the inert gas cycle is maintained under equalized pressure by a portion of the vapors passing from the fractionating column into the caustic extractor IUI) through this connecting main. The gases and vapors from the tar-acid still I2?)` combine with these vapors from the iractionating column and the combined gases and vapors pass to the caustic tower I 0b Where Vthey are extracted to recover tar acids. The resulting vapors pass to the condenser 22. In this condenser a neutral oil or oil of relatively low tar-acid content is condensed, depending upon the extentto which tar acids are extracted and removed in the extractor ilb. The cooling in the condenser 22 can be so regulated as to produce an oil of desired boiling range.

An arrangement similar to Fig. 3 is one in which the condenser is placed before the caustic extractor. The vapors from the fractionating column may blend with the lgases and vapors from the still |211, either before or after passing through the condenser.

In Fig. 4 a condenser 23 is included in the inert gas cycle preceding the caustic tower |00. Vapors from the tar-acid still I2c are cooled in the condenser 23 and a portion of the vapors condensed andV recovered as tar-acid oil in this condenser before the vapors pass on to the-caustic extractor. 'Ihe cooling in the condenser 23 may be so .regulated as to produce an oil of desired boiling range. A modification of the arrangement shown `in the drawing is one in which the gases and vapors from the still I2C combine with the vapors from the column before they enterv the condenser 23.

When operating according to Figs. 3 and 4 it is not necessary that the vapors leaving section 6b and section 6c be cooled to 200 C., since the vapors will be combined with the cooler gas of the inert gas cycle. It is sufficient that the combined gas caustic tower we. cooling in the condenser 25, an oil of relatively low stream be about 200 C. or lower before being brought into the extractor. The temperature of the vapors leaving the column through the mains 9b and 9c and the temperature of the circulating inert gases are regulated according to the respective amounts of each to give the proper operating temperature within the caustic extractors |01) and Ic.

The oils withdrawn from section 6d of the fractionating column shown in Fig. are oils of higher boiling range than those which pass in vapor form to the caustic tower 10d through the main 9d. It may therefore be desirable to extract tar acids separately from this higher boiling oil before blending vapors from the inert gas distillation in the tar-acid still |2d with vapors from the section 6d. A caustic tower 2S is therefore provided for separately treating these vapors. Caustic is sprayed into the tower 24 in order to recover the higher boiling tar acids before blending vapors from the still 12d with the vapors from the section 6d of the fractionating column. By thus separately recovering higher boiling tar acids the phenol content of the tar acids recovered in the caustic tower Id may be increased.

The apparatus of Fig. 6 is somewhat similar to that shown in Fig. 5 but in addition to the caustic tower 2de for extracting higher boiling tar acids,

a condenser 25 is shown for fractional condensation of neutral oils in the inert gas cycle before the vapors distilled in the tower 12e enter the By careful regulation of the tar acid content is thus separately collected. The temperature of the gas leaving the condenser 25 and the temperature of the gas passing from the column through the main Se are each regulated so that the temperature of the continuous gases is not above about 200 C.

A ractionating column with condensers, or simple condensers can be employed in any of the modifications shown, as desired. In the apparatus of Fig. 3 there is open communication between t-he sections 5b and 1b of the fractionating column. In the apparatus of Figs. 1, 2 and 4 to 6 the gases from the sections 6, 6a, etc., when passing to the section 1, 1a, etc., must first pass through the caustic tower I0, Illa, etc.

Fig. '1 shows an arrangement for the continuous distillation of tar and production of pitch in a simple, direct-fired still 26. The arrangement is intended for use in connection with a process in which high melting point pitch is produced. The gases pass from the still through the condensers 5f, Bf, 1f and 28 and the condensation is so controlled that the heaviest oil condensed in 5f contains no appreciable amount of desired tar acids. The oils from the condensers Bf and 1f are taracid-containing oils. They are drawn off into the tar-acid still l2f. The vapors from `'the still are cooled in these condensers soV that they leave the condenser 1j at a temperature in the neighborhood of 200I C.,and the vapors Aleaving this condenser still contain tar acids. These vapors combine with the gases and vapors from the tar acid still .I2f and pass through the extractor lf. A portion of the extracted gases and 'vapors is recirculated through the tar acid still I2f. The balancepasses to thecondenser 28, in which, on further cooling, `an oil fraction substantially free from tar acids is obtained. This oil fraction generally will contain 2% -or less of tar acids depending upon the extent to which tar acids are removed in the caustic extractor Mib.

' In Fig. 8 a cascade of stills is shown connected with condensers and a caustic extractor for carrying out this invention. The tar enters the still 30 and after partial distillation ows in Series through the stillsV 3i, 32 and 33 and is progressively distilled as it passes through the stills.

The lightest oils are vaporized in the still 30 and higher boiling oils are progressivelyY distilled from the stills 3|, 32 and 33. The highest boiling oils from the still 33 pass through the `condenser 35 and are subjected to fractional condensation therein. The residual vapors combine with the vapors from the still 32 and pass through the condenser 36. Similarly, the residual vapors from condenser 36 combine with the vapors from still 3| before passing to the condenser31. The residual vapors from lthe condenser 31 combine with the vapors from the still 30. In an ordinary distillation they pass directly to the worm condenser 34 but when tar acids are recovered they are passed through the caustic extractor |0g before passing to the condenser 34. g

The cooling in the condenser 35 is'so regulated that the oil fraction condensed therein contains no considerable amount of tar acids. The condensate from the vcondenser 31 and generally also the condensate from the condenser 36 contain tar acids. These condensates run into or are pumped by the pump 39 into the tar-acid still l2gin which tar acids are distilled from the oils by a current of inert gases.' The gases and vapors from the tar acid still |29' are blended with the vapors from condenser 31 and from still 30 and are then passed through the caustic extractor lg. 'I'he cooling in condenser '31 is so regulated that the combined vapors entering the caustic extractor Ig are at a temperature in the neighborhoodof 200 C. or lower and can therefore be extracted directly with caustic soda. Part of the extracted vapors are recirculated and again passed through the tar acid still l2g. The balance of the extracted vapors passes through the worm .condenser 34.

Instead of the single condensers arranged in series shown in Figs. `'1 and 8, a fractionating column may be employed. In each of the arrangements shown a caustic tower such as that shown in Fig. l is to be preferred for the extraction of the vapors.

The invention is not limited to the .arrangements shown in .the vdrawings or to the specic processes described. It is defined in the appended claims.

I claim:

l. The method Vof treating tar-acid and neutral-oil-containing hydrocarbon material. which comprises -distilling the material, cooling the vapors to condense part but not all of the tar acids thereby producing 'a tar-a'cid-containin-g `condensate, vaporizing tar acids from this condensate, blending-fthe tar acid vapors with uncondensed vapors resulting 'from thesdistillation of 75 the hydrocarbon material and extracting the blended vapors for tar acids by contact With an alkaline reagent.

2. The method of treating tar-acid and neutraloil-containing hydrocarbon material, Which comprises distilling the material, cooling the vapors to condense part but not all of the tar acids thereby producing a tar-acid-containing condensate, vaporizing tar acids from this condensate, blending the tar acid vapors with uncondensed vapors resulting from the distillation of the hydrocarbon material and extracting the blended vapors for tar acids by contact with an alkaline reagent, the vaporization of the tar acids being effected by the self-contained heat of the condensate.

3. The method of treating tar-'acid and neutral-oil-containing hydrocarbon material, which comprises distilling the material, cooling the vapors to condense part but not all of the tar acid vapors thereby producing a tar-acid-containing condensate, vaporizing tar acid from the condensate While still hot in a current of inert gases containing neutral oil vapors, blending the resulting gases and vapors with uncondensed vapors resulting from the distillation of the hydrocarbon material, extracting the blended vapors for tar acids by contact with an alkaline reagent and recycling at least a portion of the resulting gases and vapors to aid in the vaporization of the tar acids from the condensate.

4. The method of obtaining tar acids from tar, which comprises distilling the tar, cooling the distillate vapors to condense part but not al1 of the tar acids therefrom, thereby producing a taracid-containing condensate, vaporizing tar acids from this condensate while still hot, extracting part but not all of the tar acids therefrom by contact With an alkaline reagent, blending the resulting tar acid vapors with uncondensed vapors from the distillation of the tar and extracting tar acids therefrom by contact with an alkaline reagent.

5. The method of treating coke oven tar, which comprises heating the tar to a temperature of at least 250 C., flashing the heated tar, cooling the vapors from the flashing operation to a temperature not above 210 C., thereby producing a tar acid oil, vaporizing tar acids from this oil, blending at leasta portion of the tar acid vapors with uncondensed vapors from the flashing operation, and extracting the combined vapors by bringing an alkaline reagent into contact therewith.

6. The method of recovering tar acids, which comprises subjecting tar to distillation, cooling resulting vapors to condense a tar acid oil While leaving part of the tarI acids in vapor form, vaporizing tar acids from the tar acid oil and blending them with the tar-acid-containing vapors, and

then extracting the blended vapors by contact with an alkaline reagent.

'7. The method 0f recovering tar acids, which comprises distilling tar to pitch, cooling the vaporsto a temperature not above 200 C., thereby producing a tar acid oil while leaving tar acids in the vapor state, vaporizing tar acids from this oil, blending at least a portion of these vapors with uncondensed vapors from the distilling operation and extracting the combined vapors by contact with an alkaline reagent.

, 8. The method of recovering tar acids, which comprises progressively distilling tar in a series of stills, condensing a tar-acid-containing oil from the vapors from one of the stills, vaporizing tar acids from this oil, blending these vapors With tar-acid-containing vapors from one of the other stills and extracting tar acids from the blended vapors by bringing an alkaline reagent into contact therewith. Y

ARTHUR I-I. RADASCI-I.

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