US1299791A

US1299791A - Drying process.

Info

Publication number: US1299791A
Application number: US17259417A
Authority: US
Inventors: Stewart E Seaman
Original assignee: SEAMAN WASTE WOOD CHEMICAL Co
Current assignee: SEAMAN WASTE WOOD CHEMICAL Co
Priority date: 1917-06-04
Filing date: 1917-06-04
Publication date: 1919-04-08
Anticipated expiration: 1936-04-08

Description

s.E.sEAMAN{ DRYING PROCESS.

APPLICATION FILED IuNE 4. I9I1.

1,299,791 Patented Apr. 8, 1919.

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CmICAL C0mANY,-0F NEWYOBK, N.' Y., A. CORPORATION 0F `Ih'llllW YORK.

name rnocnss.

To'aZZ-whom-tfmay coacrhi I Kings, andState of New lYork, have invented a newand useful Improvement in' Drying'Processes, of which thefollowingis a full, clear, and exact description,

. My invention relates to improvements ina process of dryingmorelor less inely divided wood, hull-bran, nut shells,- cotton seed hulls,

cellulose, 1ignum,orother materials having a distillate worth 'saving'preparatory to subjecting such materials to. destructive distillation. ylin order -that the material may have the best' chemical yield, it is advisable to have it substantially dry, and furthermore l' this obviates the diiliculty of generating too much-*steam or other waste gases in the retort. .Heretofore, however, diiiiculties have arisen in connection with drying such materials as ysawdust and other finely divided material" of the; kind specified, in'thatso much dust is generated'that explosions frequently occur and the dried material has been dangerous to handle. e On .the other hand to get to a-low moisture content, `and with my improved process I have been able todry the material to absolute dryness withoutdanger of explosions and without loss of material.

In' carrying out this idea use a drier which can be ofany approved type, but'is 'l" preferably a rotary drier, and apply direct heat-in'which the furnace .gases of combustion are drawndirectlyor indirectly through the drier. The wetmaterialto be dried is admitted with the hot combustion gases at "611e end of the drier, the whole content is dit this. way the 'charge to be distilled .is thor withdrawnfrorn the. opposite'end by an exhanister `and then passed through a dust 'sep-v arator of the ordinary'or'any approved type.

which permits the waste gaSSahd steam'. `to escaa from' the top, while the material to be ed 4is delivered through the bottom. In

oulily' and, may be absolutely dried, while itv ees notcomein contact with Zthe atmos- Ipheric air, but is fed directly to theretort so 'that' all danger is r.f nbviated.

This will be thefdescription which foll Speci-ieation.ofLetters Patent. application met '4,-ie`17, 'lsrxa1 narrates.;

jshws the drier in a otherformskcanbeuse` l All the mat 'al 'n the drier ,is exhausted `1.0Ws, and in which theligures show a form Be it known that L'STEWART SEAMAN,

' aci'tizen ofthe United States, and a resident of the boroughv vof Brooklyn, county vof .iently used for carrying my processinto efl'fect, although other forms of driers can be used if preferred.

Patented Apr. 351919.

DSTA'EES PATENT QFFICE. l

` STEWART E.- sammelten BROOKLYN, NEW Yonx, AssIGNon. 'ro sEAMaN wasrnwoon of .drying apparatus :which-can be conveningdrawin'gs y forming a part of this specication', in which similar reference characters indicate correspondingparts in all the views."

vvFigure 1 is a side elevationlpartlyfin sec.

tion of an apparatus -suitable for the intended purpose, and

.Fig 2 is-aL cross section on theline 2-2 of` Flgn 1.

The material'which as stated is morev or less Iine'ly divided, and which is to be dist1lled, is fed in its moist form or natural condition to the hopper 10, passingthrough a gate 11 which may be counter-balanced by a weighted arm 12 .and-passes through the in- -let end 13 of a rotary cylindrical drier 14.

This drierl is arranged to receive at its inlet- -end the combustion gasesfrom` a suitable furnace 15, which can be of any approved 1 type.

Where a rotary dri'erv is used as shown it is preferably provided with some form of lifting blades as 16, which will keep the material stirred up and in the air 'so that all' parts of it 'can be subjected to the hot gases and so quickly dried.

Any suitable means vcan be used for rotating the drier, and Ihave shown a very common form of structure in which the drying cylinder'14 has collars 17 runningon supporting trucks 18 andydriven by `a gear wheel 19,

pinion 20 and suitable connection with the driving shaft 21. This structure is vnot gone into in detail for the reason that it only to pass out at the top, while the dust and dried material. drops through the bottom,-" 105;

general'` type becausel The separator 25 is [throughfan`- outlet pipe'22-which connects'fVIV with an 'exhauster '23, andthe latter d-i'scharges through appe. 24 linto a .separator 25. This vca n'be' anylusual type of separator l which permits the waste gases and steam U the separator.

sparks or embersbeing drawn through the drier and into the separator so as to produce explosions, and the exhauster 23 is preferably placed between -the drier and This is important because much line dust is generated in drying and should be removed at once, the material becomes thoroughly dried, and if any sparks should enter this dried material which is more or less gaseous, or at least is in an explosive condition, disastrous results follow.

After the material is thoroughly dried as stated, I prefer to feed it directly to the retort before it has a chance to absorb any moisture or take fire, and to this end I arrange the inlet of the retort immediately below the discharge from the separator 25, or at least arrange to feed the material directly from the separator to the retort. In

the drawing I have shown a convenient way of carrying out this idea. I-Iere the drier is shown 1n connection with a retort of the kind disclosed in Letters Patent of the United States No. 1,236,885, dated August 14, 1917, but obviously other forms of retort may be supplied from the drier if desired. As shown the dried material issuing from the separator passes into the feed hopper 26 of the retort, and from this hopper it is pushed by the ram or plunger 27 into and through the feed pipe 28 of the retort 29. Thus the air is expelled and the retort sealed. Obviously many other forms of retort and feeding devices might be used without affecting the principle of the invention. It will be seen from the description given that the entire material to be distilled passes through the drier with the gases of combustion rom the furnace, and that the entire products both of the material to be dried and from the furnace flue, pass to the separator 25 where the separation takes place as indicated, and so the dried material is never in contact with the outside air. Thus it will be seen that the dust and fine material is confined until it reaches the retort, and as the material is mingled directly with the products of combustion from the furnace it is thoroughly dried, and without waste.

From the rforegoing description it will be seen that the form of drier is not very material, but that the essential thing is to have a drying chamber through which the hot products of combustion from the furnace are drawn and to carry through thischamber the material to be dried which is thus subjected to the action of the hot furnace gases.

It will also be noticed that this process is continuous, as the drier serves as a part of a iiue through which the hot products of combustic-n from the furnace are drawn, and the material to be dried whether sawdust or other more or less linely divided material, can be continuously fed to the drier and the separation goes on continuously in the sepau rator 25.

It will be noticed that the drying cham ber or drier 14 can receive the hot gases from any suitable furnace, that the feed of the wet material is at the end of the. drier which receives the hot gases, and that the material is exhausted by suction applied to the discharge end of the drier. This is important because in this arrangement the greatest pressure is at the end nearest the exhauster, and so the wet material comes in contact with the hot gases of combustion at their point of highest temperature and the sparks are extinguished by the wet material before they can be carried through the drier to the material which has become thoroughly dried. Where attempts have been made to blow hot gases through the drier with the material to be dried, disastrous results have usually followed because the pressure then is highest at the intake end of the drier and occasionally sparks will ily through and of course ignite and explode the charge. It will -be further noticedthat this operation is continuous and that it is used in connection with a destructive still, so that the material assing from the separator passes directly to t e still through suitable feeding means, which itis not thought necessary to show here, and there is no chance for the material to pick up moisture or to create'explos'ive dusts or comtion from a furnace into said drier near the' intake of the material to be dried, drawing the mingled gases and material through the drier by suction applied at the dischargeend of the latter, separating the waste gases from the dried material, and feeding theA dried material direct to a retort.

2. The process of drying more or less finely divided material which conslsts of feeding the material to be dried to a drying chamber, drawing the hot gases of combustion from a furnace throu h such chamber whereby the chargeand t e hot gases become mingled. exhausting the contents of the drying chamber, and separatin the steam and waste gases from the dri charge at such a distance from the .drying chamber as' will preclude the carrying of sparks to the point of separation.

3. The process of drying which consists in feeding more or less finely divided material to be dried into one end of a drier, discharging the hot gases of combustion from a furnace into the inlet end of the drier, a 'tating the contents of the drier, exhausting the contents from the discharge end of the drier,

vseparating thesteam' and waste gases from p the discharge, and feeding the dried material to .aretortg continuously passin mingled hot, products of furnace combustion and material to be dried through a "drying chamber,vcont`inu ously exhausting'the contents of the chamber by suction atthe discharge end thereof, separating the steam and waste gases from the dried material, and continuously feeding the dried material to a retort.

5. The process of drying which consists in continuously passing mingled hot products of furnace combustlon and material to beA dried through a drying chamber, continuously exhausting the contents of the chamber by suction at thel discharge end thereof,

and separating the steam and waste gases -'from the drying chamber as will preclude -the carrying of` sparks or excessivelyhot gases tothe point nf separation. 4; The process of drying which consists in 6. The process of dryingV more or less nely divided materials which consists in feeding the material 'to be dried to a drying chamber, drawing the hot gases of combustion from a urnacelthrough such drying chamber and mingling the furnace gases with the material to be dried, withdrawing the contents of the drying chamber to such a distance as will preclude the presence of sparks or excessively hot gases, and then im mediately separating the waste gases and fine dust from the' dried material.

STEWART. E. SEAMAN.

Witnesses:

F. ENOSLIN, W. F. DOUGHTY.