US1195075A - Method of and apparatus for concentrating acids - Google Patents

Method of and apparatus for concentrating acids Download PDF

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US1195075A
US1195075A US1195075DA US1195075A US 1195075 A US1195075 A US 1195075A US 1195075D A US1195075D A US 1195075DA US 1195075 A US1195075 A US 1195075A
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acid
tower
flues
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B17/00—Sulfur; Compounds thereof
    • C01B17/69—Sulfur trioxide; Sulfuric acid
    • C01B17/88—Concentration of sulfuric acid
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S159/00—Concentrating evaporators
    • Y10S159/19—Acid

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  • This invention relates to a method of and apparatus for concentrating acids by the use of heat, one of the objects of the invention being to provide simple and eflicient means for agitating the acid while it is being subjectedto heat so that all portions of the acid will thus be acted on and the accumulation of substances upon the bottom of difierent portions of the apparatus will be prevented.
  • a further object is to employ apparatus in which the hot gases pass over the agitated acid. 1
  • Another object is to utilize a tower in which is absorbed any acid gas which may be driven from other portions of the apparatus by the heat, this tower utilizing that portion of the heat which escapesfrom other portions of the apparatus.
  • a still further object is to provide apparatus of this character all parts of which are built into one unit thus to obtain a simple and durable structure at a minimum cost of construction and whereby practically all of the heat is used and the maximum efliciency attained.
  • Figure 1 is a view partly in s1de elevatlon and partly inse'ctionpf the apparatus.
  • Fig 2 is a view partly n plan and partly in horizontal section. ig. 3 ,is a vertical transverse section, a portion of said section being taken on the line AB Fig. 1 while the remainder of the section is taken on the line GD Fig. 1.
  • Fig. '4. is'an enlarged section on line E-F Fig. 2.
  • suitable construction the same being preferably arched and provided with transverse tie rods 2.
  • transverse tie rods 2 Above the arch may be arranged common bricks denoted at 3 and it is designed to place over this foundation a layer of asphalt 4 on which is arranged a thickness of acid resisting bricks 5 of any preferred construction, said bricks being laid in acid proof mortar.
  • par allel concentrating flues 6 and 7 each havmg an arched top which is inclined down- .wardly and inwardly from the outer end 7 of the flue, as shown at 8 and merges into a substantially horizontal arch "9 extending practically throughout the length of the flue.
  • the walls of'each flue are preferably constructed of silica fire brick, as indicated at 10 and erected on these walls are one or hot gases. However, should these hot acid fumes penetrate to the outer layer ofbricks and condense on the ,cool surfaces, it has been found that the buter arches would be I destroyed unless they should be made of acidproof brick.
  • the acid fumes and hot gases have no corrosive action whatever 'llntll sufliciently cool to condense and :this does not occur at the temperature-to which the fire brick lining is exposed but does occur at the temperature customarily encountered at the outer arch or casing of acid-proof brick.
  • the walls 10 and bottom 5 are extended outwardly beyond the outer ends of the flues .6 and 7 and said walls 10, together with an upstanding transverse wall 13 cooperate to form a trougn 14: extending across the outer ends of the *flues and which, communicates with said flues through acid ports 15.
  • This trough has a cover 16 preferably of lead.
  • the trough is provided with extensions 17 likewise covered with-lead or the like and which can be opened to permit the insertion r cally all of the heat which leaves the of cleaning rods which can thus be directed into the ports 15.
  • Extending through the end of the trough is an outlet pipe 18 for the acid,-that end of the pipe within the trough being upturned as shown particularly in Fig. 4 so that the acid will be maintained at a predetermined level within the trough.
  • Extending into the trough is an air pipe 19 having branches 20 which extend throu h the ports 15 and longitudinally for a esired distance within the flues 6 and 7. These pipes are extended along the bottoms of the fines and those portions thereof within the flues are apertured so that jets of air will be free to escape from the pipes and into the acid contained within the flues.
  • ports 21 Formed in the end wall of the flues are ports 21 through which gas burners may be extended or, if fuel other than gas or oil is employed, hot products of combustion vfrom a furnace located adjacent the apparatus herein described, can be directed to the ports 21.
  • trough 23 communicatin g with the interior of the tower through ports 24 in the walls of the tower.
  • Spaced arches 25 are erected in the lower portion of the tower, these arches being constructed of acid-proof brick set in acld-proof cement and servin to suprgort a brid e made up of paralle rows 0 rick, as in cated at 26.
  • This bridge supports a brick checker-work indicated at 27 and above the checker-work is, arranged a filling of quartz indicated generally at 28.
  • Man-ho cs 29 are formed in one wallof the tower in line with the lines 6 and 7, these man-holes being provided with normally closed'cover lates 30. By removm the cover plates the ottom of the tower an the adjacent ends of the flues 6 and 7 can be readily cleaned.
  • a gas outlet pipe 81 is provided adjacent the top of the tower and the aorta so located that it will not obstruct't e flow of gas through this outlet pipe.
  • heat is directed into the outer an s of the flues, either b extending burners into said fiues throug the ports 21;. or by directing hot products of com ustion trom adjacent urnaccs through the ports 21.
  • Acid is spra quartz and wi trickle thcrethroug V to the bottom at the tower and then flow longitudinally oi the dues and out through trough 14 and the outlet pipe 18 which serves to conduct the acid to coolers rovidcd therefor.
  • the greatest heat wit the due: is adjacent the Iports 21 and this heat gradua 1y diminis or toward the tows practiucs ed as ordinarily u on the being used 1n the tower for action upon the descending acid.
  • concentration of the acid begins as soon as the acid is discharged into the tower, the heat increasing as the acid approaches the trough 14.
  • the acid is kept in a high state of agitation by air under pressure which is discharged through the apertures in the pipes 20 so that the accumulation of substances in the concentrating fiues is prevented and all portions of the acid in the flues is presented for direct contact with the hot gases. Consequently the concentration is effected quickly.
  • the flues can be cleaned by in sorting cleaning rods through the extensions 17 and ports 15 andv also by 0 enin the man-holes 29. Any acid gas de ivere to the tower from the flues will be absorbed within the tower by thedowncoming acid which has been sprayed from above.
  • the herein described method of concentrating acid which consists in directing hot gases over a relatively deep substantially static body or acid and of orcing air through the acid to a 'tate it and present all portions of the 'aci to the action of the ear I 8.
  • the herein described method of concentratin acid which consists in subject- 1111 a re ativsly deep substantially s atic ha y or acid to heat which increases tron:
  • the herein descnbcd method at concentrating acid which consists in directing hot gases over fa relatively dce tiall static body of acid and em upwar y between pieces or impervious matcrial, and directing acid downwardly basubIbc-ntween said pieces of material and into said body, thereby to subject the acid to an increasing degree of heat.
  • the herein described method of concentrating acid which consists in directing hot gases over a relatively deep substantially static body of acid and thence upwardly between pieces of impervious material, directing acid downwardly through said material and into said body, thereby to subject the acid to an increasing degree of heat, and then directing jets of air through the body of acid to agitate the acid and bring all portions thereof into direct contact with the hot gases thereabove.
  • cluding a tower having an arched structure in the bottom thereof, pieces of impervious material supported by the arched structure, a flue opening into the tower for holding a relatively deep substantially static body of acid received from the tower, means for directing hot gases over the acid within the flue and longitudinally of the flue to the bottomportion of the tower, there being a gas outlet adjacent the top of the tower.
  • Apparatus for concentrating acid including a tower having an arched structure in the bottom thereof, pieces of impervious material supported by the arched structure, a flue opening into the tower for holding a relatively deep substantially static body of acid received from the tower, means for directing hot gasesflover the acid within the flue and longitudinally of the flue to the bottom portion of the tower, there being a gas outlet adjacent the top of the tower, there being openings adjacent the respective ends of the flue for the reception of cleaning means.
  • Apparatus for use in the concentration ofacid including a tower, an arched structure within the lower portion of the tower, pieces of impervious material supported by the arched structure, flues extending from the bottom portion of the tower and adapted to receive acid from the tower, said flues having acid ports in their outer ends, a transverse trough extending across the outer ends of the flues for the reception of acid from the ports, an outlet member extending from the trough and constituting means for maintaining the acid at a predetermined level within the trough and flues, and means for directing hot gases over the acid within the flues and into the tower.
  • Apparatus for use in the concentration of acid including a tower, an arched structure-within the lower portion of the tower, pieces of impervious material supported by the arched structure, flues extending from the bottom portion of the tower and adapted to receive acid from the tower, said flues having acid ports in their outer ends, a transverse trough extending across the outer ends of the flues for the reception of and from the ports, an outlet member extend. ing from the trough and constituting means for maintaining the acid at a predetermined level within the trough and flues, and means for directing hot gases over the acid within the flues and into the arched structure in the tower.
  • Apparatus for use in the concentration of acid including a tower, an arched structure within the lower portion of the tower, pieces of impervious material supported by the arched structure, flues extending from the bottom portion of the tower and adapted to receive acid from the tower, said flues having acid ports in their outer ends, a transverse trough extending across the outer ends of the flues for the reception of acid from the ports, an outlet member extending from the trough and constituting means for maintaining the acid at a predetermined level within the trough and flues, means for directing hot gases over the acid within the flues and into the tower, and means for directing air under pressure into the acid within the flues to agitate the acid and present all portions thereof in direct contact with the hot gases thereover.
  • Apparatus for concentrating acid including an acid concentrating flue, said flue having an arched top comprising an inner thickness of fire brick and an outer thickness of acid proof material, said fire brick being capable of expansion and contraction independently of the acid proof material, means for drawing off acid from the flue, said means operating to maintain the acid at a predetermined level within the flue, and means for directing hot gases over the acid and longitudinally of the flue.
  • a concentrating flue having an arched top comprising an inner thickness of fire brick and an outer thickness of acid proof material, said inner thickness being capable of expansion and contraction independently of

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Description

T. C. OLiVER.,-
METHOD OF AND APPARATUS FOR CONCENTRATING ACIDS. APPLICATION FILED MAR. 22. 1916.
Patented Au 15, 1916.
3 SHEETS-SHEET 1.
1 jCQZZWfi/j wltnesses v w) I In ventor 1 I Attofneys 1 5 1 My. d e t n m a P APPLIC'ATIONYFILED'MAR.22,1916.
Z T E F. 8 I E E. s 3
-Witnesses fizm- Attorneys v T. c OLIVER.
v METHOD OF AND APPARATUS FOR COYNCENTRATING cms; APPLICATION FILED MAR-22,19I6. I 1,195,075, Patented Aug. 15,1916.
3 SHEETS-SHEET a.-
Witnesses Inventor Attorneys v UNITED STATES PATENT OFFICE.
THOMAS CLIFFORD OLIVER, OF CHARLOTTE, NORTH CAROLINA, ASSIGNOR TO CHEMICAL CONSTRUCTION COMPANY, 01? CHARLOTTE, NORTH CAROLINA.
METHOD OF AND APPARATUS FOR CONCENTRATING ACIDS.
To all whom it may concern:
Be it known that I, THOMAS C. OLIVER, a citizen of the United States, residing at Charlotte, in the county of Mecklenburg and State of North Carolina, have invented a new and useful Method of and Apparatus for Concentrating Acids, of which the following is a specification.
This invention relates to a method of and apparatus for concentrating acids by the use of heat, one of the objects of the invention being to provide simple and eflicient means for agitating the acid while it is being subjectedto heat so that all portions of the acid will thus be acted on and the accumulation of substances upon the bottom of difierent portions of the apparatus will be prevented.
A further object is to employ apparatus in which the hot gases pass over the agitated acid. 1 Another object is to utilize a tower in which is absorbed any acid gas which may be driven from other portions of the apparatus by the heat, this tower utilizing that portion of the heat which escapesfrom other portions of the apparatus.
A still further object is to provide apparatus of this character all parts of which are built into one unit thus to obtain a simple and durable structure at a minimum cost of construction and whereby practically all of the heat is used and the maximum efliciency attained.
With the foregoing and other objects in view the invention consists in certain novel details of construction and certain steps in the method of concentrating acids, which will be hereinafter-more fully'described and pointed out in the claims.
In the accompanying drawings the-form of apparatus used in carrying out the improved process, has been illustrated,
. Figure 1 is a view partly in s1de elevatlon and partly inse'ctionpf the apparatus. Fig 2 is a view partly n plan and partly in horizontal section. ig. 3 ,is a vertical transverse section, a portion of said section being taken on the line AB Fig. 1 while the remainder of the section is taken on the line GD Fig. 1. Fig. '4. is'an enlarged section on line E-F Fig. 2.
Referring to the figures by 1 characters of reference 1 designates-a foundation of any Specification of Letters Patent.
Patented Aug..'15, 1916.
Application filed larch 22, 1916. Serial No. 85,938.
suitable construction, the same being preferably arched and provided with transverse tie rods 2. Above the arch may be arranged common bricks denoted at 3 and it is designed to place over this foundation a layer of asphalt 4 on which is arranged a thickness of acid resisting bricks 5 of any preferred construction, said bricks being laid in acid proof mortar.
Erected over the brick bottom 5 are par allel concentrating flues 6 and 7 each havmg an arched top which is inclined down- .wardly and inwardly from the outer end 7 of the flue, as shown at 8 and merges into a substantially horizontal arch "9 extending practically throughout the length of the flue. The walls of'each flue are preferably constructed of silica fire brick, as indicated at 10 and erected on these walls are one or hot gases. However, should these hot acid fumes penetrate to the outer layer ofbricks and condense on the ,cool surfaces, it has been found that the buter arches would be I destroyed unless they should be made of acidproof brick. In other words, the acid fumes and hot gases have no corrosive action whatever 'llntll sufliciently cool to condense and :this does not occur at the temperature-to which the fire brick lining is exposed but does occur at the temperature customarily encountered at the outer arch or casing of acid-proof brick.
The walls 10 and bottom 5 are extended outwardly beyond the outer ends of the flues .6 and 7 and said walls 10, together with an upstanding transverse wall 13 cooperate to form a trougn 14: extending across the outer ends of the *flues and which, communicates with said flues through acid ports 15. This trough has a cover 16 preferably of lead. The trough is provided with extensions 17 likewise covered with-lead or the like and which can be opened to permit the insertion r cally all of the heat which leaves the of cleaning rods which can thus be directed into the ports 15.
Extending through the end of the trough is an outlet pipe 18 for the acid,-that end of the pipe within the trough being upturned as shown particularly in Fig. 4 so that the acid will be maintained at a predetermined level within the trough.
Extending into the trough is an air pipe 19 having branches 20 which extend throu h the ports 15 and longitudinally for a esired distance within the flues 6 and 7. These pipes are extended along the bottoms of the fines and those portions thereof within the flues are apertured so that jets of air will be free to escape from the pipes and into the acid contained within the flues.
Formed in the end wall of the flues are ports 21 through which gas burners may be extended or, if fuel other than gas or oil is employed, hot products of combustion vfrom a furnace located adjacent the apparatus herein described, can be directed to the ports 21.
Erected at that end of the fines remote from the trough 14 is a tower 22 about the.
base of which is formed a trough 23 communicatin g with the interior of the tower through ports 24 in the walls of the tower. Spaced arches 25 are erected in the lower portion of the tower, these arches being constructed of acid-proof brick set in acld-proof cement and servin to suprgort a brid e made up of paralle rows 0 rick, as in cated at 26. This bridge supports a brick checker-work indicated at 27 and above the checker-work is, arranged a filling of quartz indicated generally at 28.
Man-ho cs 29 are formed in one wallof the tower in line with the lines 6 and 7, these man-holes being provided with normally closed'cover lates 30. By removm the cover plates the ottom of the tower an the adjacent ends of the flues 6 and 7 can be readily cleaned.
A gas outlet pipe 81 is provided adjacent the top of the tower and the aorta so located that it will not obstruct't e flow of gas through this outlet pipe.
In using the ap aratus, heat is directed into the outer an s of the flues, either b extending burners into said fiues throug the ports 21;. or by directing hot products of com ustion trom adjacent urnaccs through the ports 21.
Acid is spra quartz and wi trickle thcrethroug V to the bottom at the tower and then flow longitudinally oi the dues and out through trough 14 and the outlet pipe 18 which serves to conduct the acid to coolers rovidcd therefor. The greatest heat wit the due: is adjacent the Iports 21 and this heat gradua 1y diminis or toward the tows practiucs ed as ordinarily u on the being used 1n the tower for action upon the descending acid. Thus it will be seen that concentration of the acid begins as soon as the acid is discharged into the tower, the heat increasing as the acid approaches the trough 14. The acid is kept in a high state of agitation by air under pressure which is discharged through the apertures in the pipes 20 so that the accumulation of substances in the concentrating fiues is prevented and all portions of the acid in the flues is presented for direct contact with the hot gases. Consequently the concentration is effected quickly. As has been pointed out heretofore the flues can be cleaned by in sorting cleaning rods through the extensions 17 and ports 15 andv also by 0 enin the man-holes 29. Any acid gas de ivere to the tower from the flues will be absorbed within the tower by thedowncoming acid which has been sprayed from above.
It might be stated that the fire brick lining of each concentrating flue and which lining has been indicated at 11, is not permanently cemented or joined to the acid-proof arch 12 and, consequently, said fire brick lining is free to expand and contract independently of the rest of the arch.
It is well known that when sulfuric acid is subjected to a temperature above a certain de ree it is disintegrated. It has been found, owever, that by following the process herein set forth, gases heated to very high temperatures can be caused to flow over the acid without causing disintegration, this being due to the fact that the acid is kept constantly in a cool condition by the air bubbling through'it.
What is claimed is 1- 1. The herein described method of concentrating acid which consists 'in subjecting a relatively deep substantially static body oi acidto the action of an overlying currentot hot gases and directing air through the heated acid to agitate it.
p 2. The herein described method of concentrating acid, which consists in directing hot gases over a relatively deep substantially static body or acid and of orcing air through the acid to a 'tate it and present all portions of the 'aci to the action of the ear I 8. The herein described method of concentratin acid, which consists in subject- 1111 a re ativsly deep substantially s atic ha y or acid to heat which increases tron:
one end to the other or said body and in iorcing air through the acid where subjected to the greatest degree of heat. I
4. The herein descnbcd method at concentrating acid, which consists in directing hot gases over fa relatively dce tiall static body of acid and em upwar y between pieces or impervious matcrial, and directing acid downwardly basubIbc-ntween said pieces of material and into said body, thereby to subject the acid to an increasing degree of heat.
5. The herein described method of concentrating acid, which consists in directing hot gases over a relatively deep substantially static body of acid and thence upwardly between pieces of impervious material, directing acid downwardly through said material and into said body, thereby to subject the acid to an increasing degree of heat, and then directing jets of air through the body of acid to agitate the acid and bring all portions thereof into direct contact with the hot gases thereabove.
6. Apparatus for concentrating acid, in
cluding a tower having an arched structure in the bottom thereof, pieces of impervious material supported by the arched structure, a flue opening into the tower for holding a relatively deep substantially static body of acid received from the tower, means for directing hot gases over the acid within the flue and longitudinally of the flue to the bottomportion of the tower, there being a gas outlet adjacent the top of the tower.
. 7. Apparatus for concentrating acid, including a tower having an arched structure in the bottom thereof, pieces of impervious material supported by the arched structure, a flue opening into the tower for holding a relatively deep substantially static body of acid received from the tower, means for directing hot gasesflover the acid within the flue and longitudinally of the flue to the bottom portion of the tower, there being a gas outlet adjacent the top of the tower, there being openings adjacent the respective ends of the flue for the reception of cleaning means.
8 Apparatus for use in the concentration ofacid, including a tower, an arched structure within the lower portion of the tower, pieces of impervious material supported by the arched structure, flues extending from the bottom portion of the tower and adapted to receive acid from the tower, said flues having acid ports in their outer ends, a transverse trough extending across the outer ends of the flues for the reception of acid from the ports, an outlet member extending from the trough and constituting means for maintaining the acid at a predetermined level within the trough and flues, and means for directing hot gases over the acid within the flues and into the tower.
9. Apparatus for use in the concentration of acid, including a tower, an arched structure-within the lower portion of the tower, pieces of impervious material supported by the arched structure, flues extending from the bottom portion of the tower and adapted to receive acid from the tower, said flues having acid ports in their outer ends, a transverse trough extending across the outer ends of the flues for the reception of and from the ports, an outlet member extend. ing from the trough and constituting means for maintaining the acid at a predetermined level within the trough and flues, and means for directing hot gases over the acid within the flues and into the arched structure in the tower.
10. Apparatus for use in the concentration of acid, including a tower, an arched structure within the lower portion of the tower, pieces of impervious material supported by the arched structure, flues extending from the bottom portion of the tower and adapted to receive acid from the tower, said flues having acid ports in their outer ends, a transverse trough extending across the outer ends of the flues for the reception of acid from the ports, an outlet member extending from the trough and constituting means for maintaining the acid at a predetermined level within the trough and flues, means for directing hot gases over the acid within the flues and into the tower, and means for directing air under pressure into the acid within the flues to agitate the acid and present all portions thereof in direct contact with the hot gases thereover.
11. Apparatus for concentrating acid, including an acid concentrating flue, said flue having an arched top comprising an inner thickness of fire brick and an outer thickness of acid proof material, said fire brick being capable of expansion and contraction independently of the acid proof material, means for drawing off acid from the flue, said means operating to maintain the acid at a predetermined level within the flue, and means for directing hot gases over the acid and longitudinally of the flue.
12. In acid concentrating apparatus, a concentrating flue having an arched top comprising an inner thickness of fire brick and an outer thickness of acid proof material, said inner thickness being capable of expansion and contraction independently of
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