USRE20772E

USRE20772E - Process foe producing soap having

Info

Publication number: USRE20772E
Authority: US
Priority date: 1934-06-16
Publication date: 1938-06-28
Also published as: US2123647A

Description

1938. B. CLAYTON Re. 20,772

PROCESS FOR PRODUCING SOAP HAVING A DEFINITE WATER CONTENT Original FiledvJrune 16. 1954 r/4 Z 35 36 6a z? WED 36 9 .7 62 a4 96 be A3 -I!- 34 W M Z4 65 63 f/v vz/v TOR 55mm MIN (1/: Y TON ATTORNEY- Reissued June 28, 1938 UNITED STATES PATENT OFFICE PROCESS FOR PRODUCING SOAP HAVING A DEFINITE WATER CONTENT Original No. 2,037,003, dated April 14, 1936, Serial No. 730,971, June 13, 1334. Application for re-. issue June 13, 1337, Serial No. 143,312

18Claims.

My invention relates to the manufacture of soap and an object of the invention is to provide a process of and apparatus by which soap may be produced directly in a continuous process from raw material.

A further object of the invention is to provide a process of and apparatus for producing soap continuously in which the soap is produced in solid form of any suitable shape.

A further object of. the invention is to provide an apparatus for and process of producing soap in which the moisture content of the soap produced can be accurately regulated within any desired limits. 1

Further objects and advantages will be made evident hereinafter.

Referring to the drawing, which is purely diagrammatic, is a mixing apparatus, 2 is. a heater, 3 is a separating chamber, 4 is an extrusion pump, 5 is a boiler, 3 is a cooler and extruder, I is a water injection pump, 3 is a glycerine condenser, and 3 is a water condenser of the Jet type.

The mixing apparatus consists of an alkali pump II and a fat pump l2, the pump l2 being driven by a suitable motor 3 and the pump being driven through a speed changing gear M from the pump l2. The fat which it is desired to convert into soap is taken from a fat tank l3 and pumped into a mixer H by the pump I2. An alkali tank |3 contains an aqueous solution of a saponifying alkali such, for example, as caustic soda in water, the pump taking the aqueous alkali solution or reagent from the tank It and pumping it into the mixer H. The mixed fat and reagent pass through a pipe l3 to a coil 2| of the heater 2.

The heater 2 consists of an outer shell 23 in which a coil 2| is placed, and a burner 24 supplied with fuel through a fuel valve 25. Gas or oil may be used as fuel, this fuel being ignited at the burner and the hot products of combustion passing upwardly inside the shell 23 and supplying heat to the coil 2|. In the coil 2| a reaction takes place between the reagent and the fat, soap, glycerine and water vapors, hereinafter termed the "reaction products, being delivered through a pipe 23, havihg a pressure gauge 21 and a-thermor'neter 23 therein, to a nozzle 3| in the separating chamber 3.

The separating chamber 3 consists of a tight shell 32 inside which the nozzle 3| is carried. The nozzle consists of a metal member having a constricted orifice through which the reaction products must pass. The soap pump 4 is preferably a gear or screw pump capable of handling the hot soap precipitated in the chamber 32. This pump is driven by a motor 3| and delivers the hot soap to a pipe 32.

The boiler 3 may be of any convenient type, 5 that shown consisting of a shell II in which is placed a pipe coil 32. The water in the pipe coil 32 is heated by the products of combustion from a burner 53 supplied with gas through a fuel valve 34. Steam is delivered from the boiler 3 through a pipe 33, having a thermometer l3 and a pressure gauge 31 therein, to the pipe 42.

While diil'erent forms of cooler 3 may be employed, it is desirable that one be used which tends to uniformly mix the steam delivered by 13 the pipe 33 with soap delivered from the pipe 42 and the form shown is well adapted to accomplish this result. It consists of a tight shell 3| in which is placed a coil 32 into which the mixture of soap and steam is delivered by the pipe 42. The cooled soap leaves the coil 32 through a pipe 33. Cooling water is supplied to the cooler 3 through a pipe 33, the flow being controlled by a valve 33. Hot water is delivered from the cooler 3 through a pipe 33 to a tank 31. The cooled soap is delivered through the pipe 33 to an extrusion nozzle 33, which may have a single or several orifices of any desired shape, the soap being extruded in the form of threads or as a continuous bar 33. Devices may be incorporated in the extrusion nozzle 33 to break up the threads or bar into separate pieces of soap or the threads or bar 33 may be broken up after leaving the extrusion nozzle 33.

The water injection pump I may also be a 35 screw or gear pump, being driven by a motor 1|, the speed of which may be regulated to control the amount of water injected through a pipe 12 into the coil 32 of the boiler 3.

Any gas or vapor released in the separating chamber 3 is withdrawn through a pipe 33 having a pressure gauge 35 and a thermometer 33 therein. The pipe 34 communicates with the bottom of the glycerine condenser 3. The glycerine condenser 3 consists of a tight shell 3| having in- 43 termediate heads 32 between which tubes 33 extend. The space between the heads 32 inside the shell 3| and around the tubes 33 is filled with cooling water delivered through a pipe 33 having a valve 35, this cooling water being removed 30 through a pipe 33.

Any condensate produced in the glycerine condenser 3 passes downwardly through a pipe 31 to a glycerine tank 33, the pipe 31 being about thirty feet long so that as long as the lower end of the 33 pipe is submerged in the'glycerine in the tank 98, it is possible to maintain a high degree of vacuum in the condenser 9.

Any gases or vapors which are not condensed in the glycerine condenser 9 pass through a pipe 9|, having a thermometer 92 and a pressure gauge 99 therein, to thejet condenser 9. This jetcondenser is supplied with cooling water from a pipe 94 and is provided with an air pump 95. Any water condensed in the jet condenser 9 is delivered through a pipe 98 to a water tank 91. The pipe 99 is about thirty feet long so that as long as the lower end is submerged in the water in the tank 91, a vacuum may be maintained in the condenser 9 if desired.

The method of operation is as follows:

The tank I6 is filled with the saponifiable fat which it is desired to convert into soap, this fat being warmed if necessary to a point at which it is liquid. The tank I9 is filled with an aqueous solution of a saponifying alkali, such, for example, as a solution of caustic soda in water. The fat is pumped into the mixer I1 by the pump 12 and the saponifying alkali is pumped into the mixer I! by the pump H. The variable speed gear I is adjusted so that the proportion of saponifying alkali supplied to the mixer I1 is only slightly in excess of that theoretically necessary to completely saponify the fat. The pumps II and I2 may be piston pumps but should be of such type that they can pump against several hundred pounds per square inch pressure. The mixture of saponiilable fat and saponfying alkali is delivered through the pipe i9 to the heater 2 and is heated therein by the products of combustion from the burner 24.

It will be understood that the aqueous solution of a saponiiying alkali is dispersed in the saponiilable material due to mixing in the mixer l1 and is maintained in dispersion during the flow of the material through the coil 2| of the heater. The reagent or aqueous solution of a saponifying alkali is in the form of fine drops, the surfaces oi which are in contact with the oil. of producing a reaction between the reagent and the saponifiable material by providing contact between the reagent and the oil is for convenience termed contacting."

In the coil 2| a reaction takes place between the saponifying alkali and the saponifiable fat, and soap and glycerine are formed. Sumcient heat is supplied to the mixture in the coil 2| to raise the temperature of the reaction products passing through the pipe 26, as indicated on the thermometer 29.

The reaction products, that is to say, the soap and glycerine, with all of the water content of the mixture delivered to the coil 2|, are ejected through the nozzle 3| into the separating chamber 3. The interior of the separating chamber 3 is maintained under vacuum and there is, of course, a high pressure drop as the reaction products pass through the constricted orifice of the nozzle 9i.

These reaction products emerge from this constricted orifice in the form of a high velocity jet containing steam, glycerine vapor, and particies of liquid soap. The soap is thrown violently downward to the bottom of the chamber due to the velocity of the jet and in its passage through the chamber the glycerine vapor and steam escape therefrom, passing upwardly and being withdrawn through the pipe 34. Suflicient heat should be supplied by the burner 24 to enable the temperature as indicated by the ther- This method mometer 39 of the vapors passing to the glycerine condenser 9 to be maintained above the boiling point of glycerine at the absolute pressure indicated on the vacuum gauge 95.

The soap which is delivered to the bottom oi the separating chamber 3 contains almost no water or glycerine. It is, however, at a sumciently high temperature to be liquid and it is continuously withdrawn through the soap pump 4 and delivered to the pipe 42.

Since the soap delivered to the pump 4 is practically free from water, it is desirable to add water thereto to produce a commercial soap, since such soaps usually contain from 10% to 20% of water. Thiswater content is added in the form of steam injected through the pipe I5 into the flowing stream of hot soap leaving the pump 4 through the pipe 42. The pump 4 should be capable of exerting considerable pressure since it not only takes soap from the chamber, which is under a vacuum, and extrudes it against atmospheric pressure, but it must also overcome some fluid friction in the cooler 6 and a very considerable friction in the extrusion nozzle 89. By regulating the rate of feed of the water pump I in proportion to the rate of feed of the fat pump II, a soap of absolutely fixed and definite water content can be produced.

The mixture of steam and glycerine vapor passing through the pipe 94 into the glycerine condenser 8 is cooled in its upward passage through the tubes 89 to such a degree that substantially all of the glycerine content of these vapors is condensed, this glycerine condensate running downwardly through the pipe 91 to the tank 89. The steam, freed from the glycerine vapors, then passes through the pipe 9| to the water condenser 9. The supply or cooling water delivered to the glycerine condenser through the pipe 84 is so regulated that the temperature of the steam passing through the pipe 9|, as indicated on the thermometer 92, is considerably below the boiling point of glycerine at the pressure indicated on the pressure gauge 93 and above the boiling point of water at that pressure.

In the jet condenser 9 the steam is condensed due to the introduction of cooling water through the pipe 94, the condensed water being delivered through the pipe 96 to the tank 9'I.- Any air or uncondensed vapor or gas which would tend to accumulate in the jet condenser 9 is continuously withdrawn by the air pump 95.

In practice the degree of vacuum carried in the separating chamber 3 may be regulated by suitable manipulation of the condensers 9 and 9 and the air pump 95. The degree of vacuum maintained depends somewhat upon the tempperature of the jet leaving the nozzle'3l. The higher this temperature, the higher the absolute pressure can be carried in the separating chamher 3. This pressure must be suiliciently low to promote a rapid vaporization of the glycerine, this vaporization being promoted by the fact that the chamber also contains steam, thus reducing the partial pressure of the glycerine vapors due to the law of partial pressures.

In practice the apparatus operates continuously, the tanks i6 and I9 being replenished from time to time and the glycerine and water delivered to the tanks 91 and 88 being withdrawn as they accumulate. The soap 69 extruded from the pipe 6| has a definite and constant water content. The glycerine recovered, being a distillate, is in very pure form and has a high commercial value.

If desired, the temperature in the separating chamber! can be lowered sumciently so that all or a portion of the glycerine is not vaporized and is carried over as a liquid in the soap removed by the pump '4. The same eiiect can, of course, be obtained by increasing the absolute pressure in the separating chamber. All that is necessary to permit the glycerine to be carried over into the soap with asubstantial dehydration of. the soap passing to the pump 4, is to hold the temperature in the separating chamber 3 above the boiling point oi water at the pressure maintained therein, but below the boiling point of glycerine under that pressure.

I claim as my invention:

1. A continuous process of producing soap directly from a saponiflable material by the reaction therewith of an aqueous solution of a saponiiying reagent, and recovering the glycerine pro duced by the process, which comprises: contacting the materials to produce soap and glycerine; continuously passing the mixture of soap and glycerine into an evaporating chamber; continuously removing water and glycerine vapor from said chamber at a rate suiiicient to maintain a sumcient vacuum therein to vaporize substantially all the water and glycerine in said mixture; and continuously withdrawing soap from said chamber in such a manner as not to impair the vacuum maintained therein.

2. A continuous process of producing soap directly from a saponifiable material by the reaction therewith oi an aqueous solution of a saponifying reagent, and recovering the glycerine produced by the process, which comprises: contacting the materials to produce soap and glycerine; continuously passing the mixture of soap and glycerine intoan evaporating chamber; continuously removing water and glycerine vapor from said chamber at a rate suflicient to'maintain a sufllcient vacuum therein to vaporize substantially all the water and glycerine in said mixture; maintaining the soap at such, a temperature after the glycerine and water vapor has been withdrawn therefrom that it is molten and sufilciently liq- .uid to be pumped; and pumping said soap out of said chamber as the soap is formed therein without impairing the vacuum maintained in said chamber.

3. A continuous process of producing soap directly from a saponifiable material by the reac-- tion therewith oi an aqueous solution of a saponiiying reagent, and'recovering the glycerine produced by the process, which comprises: contacting the materials to produce soap and glycerine; continuously passing the mixture of soap and glycerine into an evaporating chamber; continuously removing water and glycerine vapor from said chamber at a rate suflicient to maintain a suflicient vacuum therein to vaporize substantially all the water and glycerine in said mixture; maintaining the soap at such a temperaure after the glycerine and water vapor has been withdrawn therefrom that it is molten and sufliciently liquid to be pumped; pumping said soap out of said chamber as the soap is formed therein without impairing the vacuum maintained in said chamber; cooling said soap after it has been so pumped to atemperature at which it is plastic: and utilizing the pressure used for pumping the soap from said chamber to extrude the soap from a suitable orifice in the form of a 'solid bar.

4. A continuous process of producing soap directly from a saponifiable material by the reaction therewith of an aqueous solution o1 a saponitying reagent, and recovering the glycerine produced by the process, which comprises: contacting the materials to produce soap and glycerine; continuously passing the mixture of soap and glycerine into an evaporating chamber; continuously removing water and glycerine vaporirom said chamber at a rate sufllcient to maintain; a suiflcient vacuum therein to vaporizesubstantially all the'water and glycerine in said mixture; continuously withdrawing soap from said chamber in such a manner as not to impair the vacuum maintained therein; and adding suflicient water to said soap after it has been withdrawn from said chamber to give it a definite water content. 5. A continuous process of producing soap directly from a saponiflable material by the reaction therewith of an aqueous solution of a saponifying reagent, and recovering the glycerine pro duced by the process, which comprises: contactingithe materials to produce soap and glycerine; continuously passing the mixture of soap and glycerine into an evaporating chamber; continuously removing water and glycerine vapor from said chamber at a rate suflicient to maintain a suiilcient vacuum therein to vaporize substantially all the water and glycerine in said mixture; maintaining the soap ,at such a temperature after the glycerine and water vapor has been withdrawn therefrom that it is molten and sufficicntly liquid to be pumped; pumping said soap out of said chamber as the soap is formed therein without impairing the vacuum maintained in said chamber; and adding sufllcient water to said soap after it has been withdrawn from said chamber to give it a definite water content.

6. A continuous process of producing soap directly from a saponifiable material by the reaction therewith of an aqueous solution of a saponilying reagent, and recovering the glycerine produced by the process, which comprises: contacting the materials to produce soap and glycerine; continuously passing the mixture of soap and glycerine into an evaporating chamber; continuously removing water and glycerine vapor from said chamber at a rate sufiicient to maintain a sufficient vacuum therein to vaporize substantially all the water and glycerine in said mixture;

maintaining the soap at such a temperature after the glycerine and water vapor has been withdrawn therefrom that it is molten and sumciently liquid to be-pumped; pumping said soap out of said. chamber as the soap is formed therein without impairing the vacuum maintained in said chamber; cooling said soap after it has been so pumped to a temperature at which it is plastic; i

adding sufiicient water to said soap after it has been withdrawn from said chamber to give it a definite water content; and utilizing the pressure used for pumping the soap from said chamber to extrude the soap from a suitable orifice in the form of a solid bar.

7. A process of producing soap directly from a saponifiable material by the reaction therewith of an aqueous solution of a saponiiying reagent and recovering the glycerine produced by the process, which comprises; contacting the materials to produce soap and glycerine; continuously passing the mixture of soap and glycerine into an evaporating chamber; continuously removing water and glycerine vapor from said chamber at a rate sufiicient to maintain a sufiicient vacuumtherein to vaporize substantially all the water and glycerine in said mixture; and continuously withdrawing soap from said chamber in such a manner as not to impair the vacuum maintained therein.

8. A process of producing soap directly from a saponifiable material by the reaction therewith oi an aqueous solution of a saponifying reagent and recovering the glycerine produced by the process, which comprises: contacting the materials to produce soap and glycerine; continuously passing the mixture of soap and glycerine into an evaporating chamber; continuously removing water and glycerine vapor from said chamber at a rate sufilcient to maintain a sufllcient vacuum therein to vaporize substantially all the water and glycerine in said mixture; maintaining the soap in said chamber at such a temperature after the glycerine and water has been withdrawn that it is molten; and continuously withdrawing soap from said chamber in such a manner as not to impair the vacuum maintained therein.

9. A process of producing soap directly from a saponiflablematerial by the reaction therewith of an aqueous solution 01' a saponifying reagent, and recovering the glycerine produced by the process, which comprises: contacting the materials to produce soap and glycerine; continuously passing the mixture of soap and glycerine into an evaporating chamber; continuously removing water and glycerine vapor from said. chamber at a rate suilicient to maintain a suflicient vacuum therein to separate as vapor substantially all the water and glycerine in said mixture: maintaining the soap at such a temperature after the glycerine and water vapor has been withdrawn therefrom that it is molten and sumciently liquid to be pumped; and pumping said soap out oi. said chamber as the soap is formed therein without impairing the vacuum maintained in said chamber.

10. A process of producing soap and recovering glycerine therefrom, which comprises the steps of reacting a saponifiable material with a saponifying reagent to effect substantial saponification, thereafter passing the resultant saponifled mixture, including soap and glycerine, into a vapor separating chamber and there promoting the separation of glycerine vapors from the soap by aintaining a temperature sumciently high to cause the separated soap to be in a substantially liquid condition in said chamber, withdrawing the glycerine vapors from said vapor separating chamber at a rate suiiicient to maintain a vacuum in said chamber, withdrawing the substantially liquid soap from said vapor separating chamber without substantially impairing the said vacuum maintained therein.

11. The process of producing soap and recovering glycerine which includes the steps 01' continuously withdrawing glycerine vapors from an evaporating chamber containing a mixture of soap and glycerine, at a rate sufllcient to cause a reduced pressure to be maintained therein, promoting the separation of glycerine vapors from said soap by maintaining sufiicient temperature in said evaporating chamber to cause the soap therein to be in a liquid condition when said vapors are separated from said soap, and withdrawing the liquid soap from said chamber without substantially impairing the reduced pressure maintained therein.

12. The process of producing soap and removing vaporizable impurities therefrom which comprises the steps of mixing saponifiable and saponifying materials, advancing the mixture, under pressure, to an evaporating chamber, heating the mixture to a temperature suflicient to vaporize said impurities when said pressure is reduced, discharging the heated mixture into thesaid some evaporating chamber, continuously withdrawing vapors from said chamber at a rate suiiicient to maintain a vacuum therein, maintaining the soap in a substantially liquid condition until removed from said chamber and removing'said soap from said chamber substantially as soon as the same collects therein without substantially impairing the vacuum maintained in said chamber and during the concurrent introduction of the mixture to the evaporating chamber.

- 13. The process 01 producing soap and removing therefrom vaporizable impurities which comprises the steps of admixing saponiflable and saponifying materials to effect substantial saponification, introducing said mixture into an evaporating chamber, maintaining a temperature upon said mixture sufllcient to vaporize the vaporizable constituents thereof and to maintain the soap in said chamber in a molten condition until removed, withdrawing the vaporized constituents at a rate suflicient to maintain a vacuum in said chamber, and withdrawing the molten soap irom the chamber without breaking the vacuum main tained therein.

14. The process of producing soap and removing vaporizable impurities which includes the steps of continuously withdrawing the vaporizable impurities from an evaporating chamber containing a mixture of soap and vaporizable impurities, at a rate suflicient to cause a reduced pressure to be maintained therein, and continuously withdrawing the soap from said chamber without substantially impairing the reduced pressure maintained therein.

15. The process of producing soap and removing vaporizable-impuritles therefrom which comprises the steps of pumping under pressure a stream of previously saponified soap and said impurities to a vapor separating chamber, heating the stream during its advancement to an extent sufliciently high to vaporize said impurities during the advancement of said stream, introducing the thus heated stream to an evaporating chamber maintained under a vacuum whereby said impurities are separated as vapors from said soap, continuously withdrawing the soap while the stream is being continuously introduced to the'vapor separating chamber.

16. The process as defined in claim 15 in which the impurities are separated as vapors with the aid of steam functioning to reduce the partial pressure of said vapors.

17. A continuous process for producing soap and recovering glycerine which comprises the steps of pumping together saponifiable and saponifying materials, advancing the resultant mixture as a stream through a reaction zone to eifect substantial saponification and the formation of glycerine, supplying suflicient heat to the mixture as it is continuously advanced through said reaction zone to vaporize at least a portion of said glycerine, continuously introducing the mixture oi soap and glycerine thus produced into an evaporating chamber, continuously withdrawing the glycerine vapor from said chamber at a rate sufficient to maintain a partial vacuum therein, maintaining the soap at such a temperature after the glycerine has been removed therefrom that it is in a substantially molten condition, continuously withdrawing the said molten soap in its anhydrous and substantially glycerine free state from the evaporating chamber without substantially impairing the partial vacuum therein maintained and continuously subjecting the soap after materials in said zone to cause substantially complete vaporization oi said vaporlzable materials when said mixture is introduced into a vapor p rating chamber. introducing the mixture to said chamber, continuously withdrawing said vapors from said chamber at a rate suincient to maintain a vacuum in said chamber and withdrawing the soap from the vapor separating chamber without substantially impairing the said vacuum maintained therein.

ENJAMIN CLAYTON.