US1362875A

US1362875A - System for the treatment

Info

Publication number: US1362875A
Authority: US
Publication date: 1920-12-21
Anticipated expiration: 1937-12-21

Description

T. R. A. KOCHER.

SYSTEM FOR THE TREATMENT OF CELLULOSE OR THE LIKE.

APPLICATION FILED FEB- 21, 1917.

1362,875, I I Patented Dec-21,1920.

W 4% W M A TTORNEY UNITED STATES PATENT OFFICE.

RUDOLPH A. KOCHER, or SAN rnnivcrseo, CALIFORNIA,

SYSTEM FOR THE TREATMENT OF GELLULOSE OR THE LIKE.

1,3easv5.

To all w/e om it may concern:

Be it known that I, RUDOLPH A. KooHnn, citizen of the United States, and resident of San Francisco, in the county of San Francisco and State of California, have invented certain new and useful Improvements in Systems for the Treatment of Cellulose or the like, of which the following is a specification.

My invention relates to improvements 1n systems for the treatment of cellulose or the like and is particularly adapted for the treatment of cellulose with a hydrolyz ng agent or agents for the purpose of changing the cellulose into other products, for example, glucose, which may then be fermented to produce alcohol. The object of the invention is to provide a system in which not only may the cellulose material be treated quickly, effectively and efficiently,

but also in which the treating materials may be eflicicntly generated and stored and effectively recovered for continued use.

Further and more specific -objects, features and advantages will more clearly appear from the detailed description given below, taken in connection with the accompanying drawing, which forms a part of this specification and illustrates more or less diagrammatically a system embodying the invention in one form.

Referring to the drawing, 1 represents a treatment container, comprising a horizontal cylinder provided with an external jacket 2, into which water may be introduced through a pipe 3 and taken off through a pipe 4 for the purpose of cooling the contents of the container 1.

If it is desired to heat the container and the contents therein, the water valves 5 and 6 are closed and steam is admitted through the pipe 7 by opening valve 8. The steam may be conducted from the jacket through a pipe 9 by opening the valve 10. If the container 1 be large, internal heating means may be provided centrally located within the container 1. I have shown for this purpose a hollow shaft 11, which hollow shaft is journaled at each end of the container and carries on one end a gear 12, meshing with a gear 13, which is driven by a belt from any suitable source of power. A. steam connection may be made with the hollow shaft 11, so that steam may be introduced thereinto for the purpose of heating the material in the middle of the container 1.

Specification of Letters Patent. Pat t d D 21 1 Application fi1ed February 27, 1917.

serial No. 151,175.

The shaft 11 carries four spirally arranged agitating blades or scrapers, 14 and 15, only two of which are shown, the other two belng located diametrically opposite the two shown. The blade 14 tends to move the material in the container 1 in one direction horizontally of the container, while the blade 15 moves the material in the other direction, so that during treatment, these blades move the material being treated back and forth horizontally of the cylinder 1. After the treatment is completed, an outlet 16 may be opened in the bottom of the container and as the material is moved back and forth, it will be delivered to the outlet at 16 and deposited in any suitable container, which may be placed beneath the outlet.

The material is introduced into the container through a manhole 17 as from a hopper 18.

The system may be effectively used for carrying out the processes described in my applications, Ser. No. 65676, filed Dec. 8, 1915, Ser. No. 130563 filed Nov. 10, 1916 and Ser. No. 132584 filed Nov. 21, 1916, in which the treatment of wood cellulose with hydrochloric acid of at least 39% strength, under certain conditions of pressure and temperature, to hydrolyze cellulose to glucose, is described.

lVhile the system is suitable for the use of various treatin agents, it is more particularly adapted to the use of a halogen acid for the treatment of cellulose, and in particular, hydrochloric acid. The cellulose is treated with hydrochloric acid of at least 39% strength in order to bring about the desired conversion, and in order that this acid may be easily and effectively recovered, only a small amount of liquid acid is used. I preferably use only from 4:0 to of water in the liquid acid based on the weight of thecellulose material. In order that the treating acid may be kept to the desired strength, even although the temperature is somewhat raised to hasten the conversion, 1 provide means for introducing the gas of halogen acid, as, for example, HCl gas into the container under pressure after the air has been withdrawn therefrom.

The hydrochloric acid gas may be stored under pressure in a tank 20 or other storage means, and leading from the tank 20 is a pipe 21, through which the hydrochloric acid gas may be introduced into the container 1 by opening the valves 22, 23 and If the gas within the tank is not under suflicient head of pressure to introduce the gas into the container 1 under sufiicient pressure, the valve 22 may be closed and the valve 25 opened and the force pump 26 set into operation, so that the pump 26 will force the gas into the container 1 under sufficient head of pressure. In order to determine the pressure at any time, the container 1 is provided with a recording pressure gage 27.

The treating of the material in the tank with the hydrochloric acid gas causes the temperature to be raised, and in order that the same may not be raised beyond the desired point, a recording thermometer 28 is provided for indicating the temperature within the container 1, and in case the temperature tends to rise above the desired point, cooling water or brine may be introduced through the pipe 3 into the jacket of the container to maintain the temperature at the desired value. After the conversion has taken place, the hydrochloric acid gas may be removed from the containerand recovered for further use.

For this purpose, I provide in the system an air-tight container 29, containing diluted hydrochloric acid, down to the bottom of which extends a pipe 30, connected with the main pipe 21, leading to the container 1, through a valve 31. Leading from the container 29 to a water cooled condenser 32 is a pipe 33 provided with a valve 34.. The condenser 31 is provided with pipes 35 connected to headers 36 and 37, pipes 35 being cooled by the surrounding cold water in the condenser, which water may be introduced through a pipe 38 and which may leave the condenser through apipe39.

Connected to the header 37 is a pipe 40, which leads to a scrubber or air-tight tank 41 containing pieces of pumice stone and sulfuric acid for the purpose of thoroughly drying the gas passed therethrough. The pipe 40 extends to the bottom of the scrub ber 41 and is provided with a valve 42, The acid in the scrubber 41 may be renewed or removed through the pipe 43. A pipe leads from the top of the scrubber 41 through a valved pipe 45 to an exhaust or evacuating pump 46. The other side of the pump 46 is connected to a pipe 47, which in turn is connected to a pipe 48 leading to the external atmosphere, the pipe 48 being provided with a valve 49. Pipe 47 is provided with a valve 50 and leads to the force or pressure pump 26. In the pipe connection between the pressure pump 26 and the main pipe 21, there is provided a pressure chamber 51 of any suitable kind, and if desired a check valve may be placed in the upper part of pipe 21. to prevent any back flow of gas from the container 1 toward the tank when the gases in the container 1 a1e"'under pressure, and likewise a check valve may be placed in the pipe 30, so that when the container 1 is being evacuated, there will be no back flow of gases or vapors into the container 1.

In operation, after the conversion has been carried out to the desired extent, the valve being closed and the valve 24 open, the valve 31 is opened and the gas within the container 1 being under pressure, immediately passes into the tank 29, Where any solid foreign particles or solid matter may be taken up bythe dilute hydrochloric acid, after which the gas passes through the pipe to the condenser 32, in'which practically all of the hyrochloric acid solution in the gas is condensed to form liquid hydrochloric acid solution which is collected in the header 36. From the condenser 32, the gas passes in the scrubber 41, where it is thoroughly dried and purified.

From the scrubber 41, the gas passes through pipe 44 and assuming the exhaust pump valve 52 to be closed and the valve 53 in by-pass about the pump 46 to be open, the gas will pass directly to the pipe 47 and if it is not desired to save the same, it may be. allowed to escape to the atmosphere through the pipe 48, the valve 50 being closed. As it is generally desirable, hoW- ever, to save this purified hydrochloric acid gas for further use, it is preferably conducted to the pressure pump 26 by closing valve 49 and opening valve 50, which pressure pump will force the gas under pressure into the storing means 20, so that it may again be used for treatment of material.

latter as much of the gas in the container 1 as will come oil without evacuation has been removed in this manner, the valve 53 is closed, the valve 52 is opened and the exhaust pump 46 put in operation to remove as much of the gaseous matteras possible from the container 1. If the temperature of the container be properly adjusted, not only will all of the hydrochloric acid gas be given ofi from the container 1., but 'HGl gas will begiven off from the liquid hydrochloric acid present inthe material until the strength of liquidacid inthe material is reduced to about 20% and then if the temperature of the material be at the proper point, even a large amount of this liquid hydro- :hloric acid of about 20% strength, may 0e vaporized and so withdrawn from the material in the container 1. This liquid hyro- :hloric acid will be condensed in the conlenser 32 and so saved for further use.

When a new charge of cellulose material has been introduced into the container, this hydrochloric acid condensed in the header 36 may be used to supply the necessary amount of water to the new charge in the container by opening valve 53 in the pipe 54 leading from the bottom of the header 36 to the pipe 21, which leads to the container 1. Likewise, the dilute hydrochloric acid in the container 29, after it has been charged as far as desirable with foreign matter, such as wood parts, etc., drawn off from the container 1 with the gas, may be discharged into the container 1 by opening valve 55.

In order that any loss of hydrochloric acid gas may be promptly and efiiciently replenished to the system, 1 provide a gas generator at 60 of any suitable kind, from which a pipe (51 leads to the header 36 of the condenser 32, the pipe 61 being provided with a valve 62. When it is desired to replenish gas tothe system, the generator 60 is put in operation and as the gas is generated,

that l r v 2 U f,

WNWliltlttllllllllllmdtnw V valve 62 is opened and the pumps and 26 set in operation, so that the gas is drawn through the condenser 32 and scrubber 411 to purify the same and then is forced into the storing apparatus 20 by the force pump 26.

Before charging the hydrochloric acid gas into the container 1, it is desirable to remove or exhaust most of the air from the container and this may be done byclosing valve 50 and opening valve i9 and setting the exhaust pump -16 into operation. The air will then be drawn from the container 1 through the pipe 21, the tank 29, condenser 32 and scrubber 4:1 by the exhaust pump 16 and discharged therefrom to the atmosphere through pipe 48. Afterthe air has thus been evacuated from the chamber 1, valve 31 may be closed and valves 22 and 23 opened, so that under pressure in the tank 20 may be admitted to the container 1 as first described.

While I have illustrated only a single treatment container 1, a single tank 29, a single condenser, a single scrubber, a single vacuum pump, a single force pump and a single storage tank, it is obvious that all of these elements as well as others, may be duplicated and operated in series, that is, the gas obtained from the operation after the treatment; of the material in the container 1 may be purified as described and then discharged into the storage means for use in a second container and so on. Likewise, the hydrochloric acid recovered in the condenser 32 may be used for providing moisture and some of the acid required in a second container. Several of such systems may be thus connected up in series, and, if desired, the last may be connected to the first so that a cyclic path of operation is provided. In such a case, it is not necessary that the gas recovered from one operation be put into a storage means prior to its being used in a second operation, but it may be forced directly into the second treatment container by the force pump, which container thus acts as a storage means. In order that the amount of evacuation of the container 1 may be easily known, a recording vacuum gage 63 is provided on the container 1.

.In using the system for the treatment of wood cellulose material, such as sawdust, to produce glucose, I preferably keep the temperature between and 60 C. and the gas is preferably maintained at such a pressure as to insure a constant excess of gas above the rate of absorption of the gas by the moisture and porous material. I prefer to feed the gas at such a rate as to maintain a pressure in the converter of from 40 to 60 pounds per square inch. The greater the pressure, the quicker the desired or necessary strength of acid is formed with the moisture or dilute acid already present in the mixture. This strength of acid should be at least 39% if HCl is used. For con- .venience in actual operation, I prefer to use approximately saturated acid. The strength of saturated acid is, of course, different for different degrees of pressure and temperature, so that for increases of temperature, as, for example, 40' to 60 (1, the pressure must be raised at least sufficient to form or maintain an acid of 39% strength. that this pressure is for any given temperature may be easily calculated. The time required to saturate large quantities of material in the manner indicated varies from one-half hour to two hours, depending upon the degree of cooling, amount of agitation and pressure.

There will usually follow a short period during which the material stands at a temperature of 10 to, 60 C. after the necessary strength of acid has been reached and during this period of heating at this temperature, it is not always necessary to agitate the material. The higher the temperature used and the greater the strength of acid used, the shorter the time it takes to produce the desired conversion. The conversion can be carried out at ordinary room temperature, although this takes somewhat longer, and if desired the saturated acid may beformed at ordinary room temperatures and then later the conversion accelerated by increasing the temperature of the material. The heat formed during the absorption of the HG]. gas may be used to accelerate the hydrolysis. As an example, it may be stated from actual experience that material which stood in contact with acid of 42% strength had reached the maximum conversion, after standing for one hour at 40 to 45 0., in one-half hour at C.

Provided that the treatment is such that the cellulose is not only converted to glucose, but the glucose has to some extent been reconverted to other materials, then the mass, after being dried out and removed from the container 1, may be boiled with water to reconvert these materials to glucose or to similar fermentable products.

The amount. of water added V is generally such as to form about a 30% glucose solution a after this final hydrolysis has taken place. place-in thecontainer 1, the heat being applied by turning steam into the jacket 2 of the container, or by turning-steam directly into the interior :of theichamber or container 1. Or thiszstep mayzbecarried out= ini an autoclave:

Following-this -step,-the material may be further diluted and is ready-forfermentation without the necessity of'separating the glucose material fromitheiinsoluble residue or lignine. The-amountsof acid :remaining is such asito form'iapproximately a 1%acid solution when the:first water is'added to form the 30% glucosesolutionn Itis also obvious-'thatainstead ofooperating a nume berof converters and connecting pieces of apparatuswin series that they may be operatedsincparallel and if desired, the storage i'tanks -may: all be connected together.

Likewise, if desired, afterthe conversion of e the material has taken place in container-l,

it may be discharged into a second container of the system, wherein the hydrochloric acid mayfbe removed therefrom in the manner described, and then it may be discharged into another container 1, .in which water maybe added to it .to produce anydesired reconversion;

All parts with which the acid comes in contact'are suitably protected by a coating of acid resisting material.

While I have described myimprovements in great idetailrwithrespect to one embodiment thereof-,1 .do-not desire to be limited to such details-since many changes and modificationsother 'than those mentioned may bemadewithout departing from the spirit and scope of my invention in its broader aspects.v Hence, it is desired to cover all. systems coming within the language of theappended claims.

hat I claim as new and desire to secure by Letters Patent is:

1. A system for the treatment of cellulose or the like, having in combination a treat ment containenmeans for introducing a hydrolizing acid gas into said container'and means for withdrawing said gas from said container andstoring it, and means for condensing a solution of the acid gas from said gas, on its way to be stored.

2. A system-for the treatment of cellulose or the like, having in combination a treatment container, means for introducing a hydrolizing acid gas into said container and. means for withdrawing-said gas from said container and storing it, means for remov ing moisture or Water vapor from said gas on its way to 'be stored, and for removing foreign particles from said gas on its way to be stored, and for condensing a solution This boiling With-water may take of the acid gas fromsaid gas, on its way to be stored 3. A system for the treatment of cellulose or the like, comprising a treatment container; withmeans for agitating the material therein, meansfor-introducing halogen acid gas into'sa'id container,- means for withdrawing: halogen acid gas from said container 'and'storing it under pressure and means forcondensing a solution of halogen acid from said gas, on its way to be stored.

Asystem for the treatment of'cellulose orthe like, having in combination a treatment container, means 'for'storing a gaseous cellulose hydrolyzing agent under pressure, ineansrforcondu'cti-n'g said gas from said storage means and introducing it intosaid container "under pressure, an exhaust pump for withdrawing the gas 'from said container and a force pump for forcinggas so Withdrawn, into said storing means under pres sure.

A system for the-treatment of cellulose or'theilike, having ZlIFCOIIlblIliLtlOIl a treatment container, means :for generating a halogen acid gas, means for storing said gas, means-forforcing the gas from said generating means intosaid storing means-under pressure,'means for'conducting the gas from said. storing means to said container, and means for Withdrawing the gas from said container and conducting it to said forcing means to be forced into said storing means under pressure.

6. A system for the treatment of cellulose or the like, having in combination a treatment container, means for generating a hydrolizing acid gas, means for storing said gas, means for forcing the gas from said generating meansinto said storing means under. pressure, means for conducting'the gas from said storing means to said container, and means forrwithdrawing the gas from said container and means for removing moisture from said gas on its Way to the storing means.

7. A system for thetreatment of cellulose or the like, havingin combination a treat ment container, means for generating a halogen acid gas, .means for storing said gas, means for forcing the gas from said generating'means into said storing means under pressure, means for conducting the gas from said storing means to said container, and means for withdrawing the gasfrom said container and conducting it, to said forcing means to be forced into said storing means under pressure, and means for removing moisture from'the gas on its way'from the generating means to the storing means and from the gas on its way from the container to the storing means.

8. A system for the treatment of cellulose material or the like, having-in combination a treatment container with means for agitating the material therein, means for varying the temperature in said container, means for forcing hydrochloric acid gas into said container under pressure and means for evacuating said container to remove hydrochloric acid gas and hydrochloric acid gas solution from the container.

9. A system for the treatment of cellulose material or the like, having in combination a treatment container, with means for agitating the material therein, means for varying the temperature in said container, means for forcing a hydrolyzing acid gas into said container under pressure and means for evacu' ating said container to remove acid gas and acid gas solution from the container, and means whereby both the acid gas and acid solution may be purified and stored and again returned to said container.

10. A system for the treatment of cellulose material. or the like, having in combination a treatment container with means for agitating the material therein, means for Varying the temperature in said container, means -for forcing halogen acid gas into said container under pressure and means for evacuating said container to remove halogen acid gas and halogen acid solution from the con tainer, means for separating the halogen acid solution from the halogen acid gas and means for returning the halogen acid solution to the treatment of material independently of the halogen acid gas.

11. A system for the treatment of cellulose or the like comprising a treatment container, means for introducing an acid gas into the container under pressure, to act upon the cellulose material or the like in the container, means for separating acid gas from the material treated and means for condensing a solution of the acid gas so separated and mixing it with a fresh charge of cellulose or the like to be treated in said container.

12. A system for the treatment of cellulose or the like comprising a treatment container, means for introducing an acid gas into the container under pressure, to act upon the cellulose material or the like in the container, means for separating acid and acid gas from the treated material and means for'condensing a solution of the acid gas so separated and mixing both the acid solution and gas with a fresh charge of cellulose or the like to be treated in said container.

Si ned at Decatur, in the county of Adams and tate of Indiana, this 22nd day of February A. D. 1917.

RUDOLPH A. KOOHER. lVitnesses:

C. J. LUTZ, FRED B. SMITH.