US1323847A

US1323847A - of tubize

Info

Publication number: US1323847A
Authority: US
Publication date: 1919-12-02
Anticipated expiration: 1936-12-02

Description

A. DRYEN. METHOD FOR THE CONCENTRATION OF SULFURIC ACID. 1,323,847.

Patented Dec. 2,1919.-

* UNITED STATES PATEN oFIuoE.

ACHILLE DRYEN, OF TUBIZE, BELGIUM, ASSIGNOR TO SOCIETE ANQNYME FABRIQUE DE SOIE ARTIFICIELLE DE TUBIZE, OF TUBIZE, BELGIUM.

I METHOD-FOR THE CONCENTRATION OF SULFURIC ACID.

Appilcation filed June 2 5, 1915 Serial No. 36,190.

To all whom it laay concern: I

Be it known that I, AornLLn D RY EN, a subject of the King of Belgium, resldmg at Tubize,in the Kingdom of Belgium, have invented certain new and useful Improvements in Methods for the Concentration of Sulfuric Acid, of which the following is a specification.

' evaporating elements which are arranged in a stepped order and communicate with one another in such a manner that the acid flows from the uppermost to the lowermost ele-.v

ment while'the vapors, which are produced by the ebullition of the acid under the action of asource of heat acting from outside, pass from the lowermost to the uppermost element of the'series.

My invention hasfor its object to secure 'a' more perfect utilization of the heat contained in the vapors which are'produced,

than has been hitherto obtained and further .quantity of vapor at a lower temperature and having less sulfuric acid than the vapors coming from the evaporating elements,

The annexed drawing shows dlagrammatically by way of example a vertical section through an apparatus suitable for carrying my invention into practice.

The apparatus comprises a number of closed elements a of suitable material such as cast-iron adapted to resist the. action of acids or platinum (especially for strong acids) or ordinarily lead (for weak acids).

,The said elements are arranged in stepped order, as shown in the drawing and'communioate with one another through pipes Z),

securing the "circulation of the acid and maintaining a constant level in each element.

The lowermost element of the series is provided with a conduit 0 for the flowing out of the concentrated acid and the uppermost element is connected by a conduit d to Specification of Letters Patent.

Patented Dec. 2, 1919.

a heater for the acid which is to be fed to the elements. The several elements, three in the example shown, are further connected with each other by conduits 7 which are provided in order to conduct the vapors generated in a given element to the next upper element. As shown on the drawing, each of the conduits 7 opens in the next upper element beneath the level of the acid contained in the latter element. The uppermost element, Which is fed with sulfuric. acid through the conduit d, is connected by a conduit g to a" tubular heater "or coil 71, adapted to heat the acid which is to be concentrated.

Said tubular heater or coil h is connected to a second 0011 i placed in a cooling-vat proranged in such a manner that the concentratmg elements a, present the greatest surface possible to the action of heating gas pro- .vided with connections is for a water-circulation. The whole of the apparatus is ar-- duced in a furnace Z or to any other heating medium. I 7

\Yhenthe apparatus is in action, the acid w'h1ch is to be concentrated, flows from the heater 6 through the conduit (1 intothe uppermost element a of the series of elements and thence flows successively, in a descendmg course, through the conduits b in the different elements composing the apparatus and escapes "finally through the conduit 0.

The vapors which are produced in the lowermost element are conducted through the conduit f in the next upper element Where they are led, as shown by the arrow into the mass of 'liquid contained in said element. Again the Vapors produced'in the second element of the series are similarly conducted in the third element of the series into the mass of liquid contained therein, and so on.

Finally the vapors produced in the last or uppermost element of the series are conducted through the conduit g into the coil h of the heater 6 where they are condensed and afterward cooled when circulating in the coil 2' of the cooling vat It will be observed, consequently that the mixture of vapors of sulfuric acid and Water, which is produced in. a given element, is always conducted into a liquid mixture of sulfuric acid andwater having less strength or concentration than the mixture which has produced thesaid vapors. A condensation of the vapor of sulfuric acid takes place consequently and the heat'which is set free by this modification of sta.te,'again secures the vaporization of a certain quantity of water. If a condensation of a certain quantityof water-vapor also takes place, the heat of condensation of said vapor and the heat due to the reaction between said water of condensation and the sulfuric acid are equivalent to the quantity of heat which is neces sary for the re-separation of a corresponding quantity of water and its reevaporation with this difference, however that the new vapors, which are produced have a temperature which is lower than that of the first mentioned vapors.

As a result, the vapors which are produced in a lower element, owing to the fact that they are conducted into the mass of liquid contained in the next upper element, are replaced by a corresponding quantity of vapors having a lower temperature and less sulfuric acid than themselves. But as the temperature of the vapors which are produced in a given element, is considerably lower than the boiling temperature of the liquid, the temperature of the vapors pass ing through the mass of liquid contained in the next upper element, may be lower than the boiling temperature of said liquid. On the other hand, the vaporization of any quantity'of water,}oth er than that corresponding to the condensation of the vapors coming from the preceding element, requires not only the evaporating heat but also a new quantity of heat whichis equivalent to the heat of reaction between sulfuric acid and water.

Said quantity of heat which is necessary to secure a concentration'in the next element,

- is furnished by the furnace Z or by any other sourceof heat, for instance by coils heated by gas or vapor at a suitable .temperature.

These theoretical considerations show that the economical utilization of theheat contained in the vapors which are set free and the condensation of the sulfuric acid contained in said vapors, are not necessarily bound to the passage of the vapors which are produced 1n a given element, into the mass of-liquid contained in the next upper element but that a similar result could be obtained by collecting together the vaporswhich are produced in the different elements of the apparatus and then leading said vapors conjointly in the uppermost element in which the sulfuric acid is led for the purpose of concentration Each of the elements composing-the apparatus could evidently be subdivided in a number of compartments arranged in stepped order so as to increase the number of passages or bubbling of the vapors through the inass of liquid contained in each element.

-Having thus described my invention, what I claim is:

1. A method of concentrating sulfuric acid which comprises heating separat 1' 1- nines of acid confined against direct contact with the roducts of combustion of the source of ieat, conducting the vapor produced by each volume of acid into acid of less concentration, the contact of the vapor with the acid of less concentration causing the evolution of vapor containing less sulfuric acid than the vapor of the acid of higher concentration and conducting acid from one volume to the volume of acid of greater concentration.

2. In an apparatus for concentrating sulfuric acid, a series of closed Vessels each adapted to hold sulfuric acid of a'different degree of concentration, means for heating each of said vessels, conduits connecting said vessels for conducting the sulfuric acid from one vessel to the next vessel containing sulfuric acid of a greater degree of concentra tion,- and conduits connecting said vessels vessels for conducting the sulfuric acid from one vessel to the next vessel containingv sulfuric acid of a greater degree of concentration,conduits connecting said vessels for conductingthe vapors. given off in each vessel to the next vessel into sulfuric acid of a less degree of concentratiom'a conduit for conducting weak sulfuric acid to the first vessel of said series, a heating coil, and means for conducting the vapors from said first named vessel to said heating coil and said heating coil being arranged to heat the Weak sulfuric acid in saidv conduit.

4. A method of concentrating sulfuric acid which comprises heating several voltunes of acid to the boiling point, maintain-1 ing the acid out of contact with the products of combustion of the source of heat, conducting the vapor produced by each volume of acid into acid of less concentration, the contact of the vapor with the acid of less concentration causing the evolution of vapor containing less sulfuric acid than the vapor of the acid of higher concentration, and conducting acid from one volume to the volume of acid of greater concentration.

In testimony whereof I have aflixed my signature in presence of two witnesses.

JAC UE BEDE, CHARLES ROY NASMITH.