US2240921A - Chemical apparatus - Google Patents

Description

I May 6 1941 c, E. ANDERSON 2,240,921y

I CHEMICAL APPARATUS Filed oct. 4, 195s INV NTOR l l l l l l l l l l l l l l l l l.

ATTORNEY Patented May 6, 1941 UNETE STTES azien si" orties CHEMICAL APPARATUS Application October 4, 1939, Serial: No. 297,913

(Cl. Zit-284) 3 Claims.

This invention relates to the 'manufacture of sulfuric acid by the chamber process and is directed to improved equipment designed to lessen the hazard of handling hazardous fumes and to admit of access into the equipment for inspection and repair without danger to the workman.

In the operation of the lead chamber system it is necessary periodically to inspect the spray heads used to introduce water into the chambers. In removing these spray heads the Workman is momentarily exposed to the chamber gases which escape into the atmosphere due to the slightly positive pressure in the chambers. These gases consist mainly oi sulfur dioxide and nitrogen oxides, and with the present available equipment it is impossible for the workman entirely to escape exposure as the fumes spread over the top of the chamber. Although in removing a spray the workman may be exposed to the fumes only momentarily, he nevertheless may inspect and wash a large number of sprays at one time, and the accumulative effect of the repetitive exposure is considerable land may lead eventually to harmful effects.

It is an object of the present invention to avoid this hazard and to provide apparatus particularly adapted to be applied to lead chambers for this purpose. Other objects will appear hereinafter.

These objects are accomplished by the present invention, a representative modification of which is illustrated within the accompanying drawing in which Figure l is a partial section in elevation taken transversely through a lead chamber, and Figures 2, 3, and 4 are detail views.

In the drawing I represents the top of the conventional lead chamber; 2 are externally supported transverse beams adapted to support the top of the chamber by means oi the lead straps 3 burned as at 4 to the top of the chamber. A support 5 is provided across the beams 2, and on this support rests a shallow lead pan 6 which is provided with a lead lute 'I composed of an ann nular chamber 8 1adapted to hold a body of water and an inverted cap 9 provided with a flangeA lil adapted to seat in the annular chamber 8 to provide a liquid seal. The inner wall il of the annulus is formed as a continuation oi a tube or pipe I2, which is burned as at I3 into the top of the chamber to provide an aperture through which the spr-ay head Ill may be inserted. The

lute cap 9 is burned to pipe I5 at i6 and forms a unitary part of and acts as a support `for the spray head.

Means is provided whereby a fluid pressure curtain can be set up and maintained across the pipe I2. When it is desired to remove the spray head for inspection and repair this pressure curtain may be set up to prevent discharge of noxious fumes into the atmosphere and yet Without in any way interfering with the removal of the spray head. This pressure curtain is set up by spraying Water, air, steam, or other suitable fluid through the nozzles I'I into and across the internal cross section of the pipe I2. This nozzle, as best seen in Figures 2, 3, and 4, has a flat oblong orifice I8 which is substantially the width of the pipe I2 and is so located in the pipe `as to direct a thin sheet of fluid transversely across the interior of the pipe. As best shown in Figure 2, the nozzle is inserted in the pipe I2 at an angle so as to direct the iiow of uid toward the interior of the chamber, thus creating a zone of pressure in the tube I2 suiiicient to offset the operating pressure in the chamber. Egress of noxious fumes from the chamber is prevented because the pressure in said zone is positive with respect to the operating pressure and any flow of gas is from said zone into the chamber. Thus, as illustrated in Figure 2, the nozzle II is burned into the pipe I2 as at I9 at an angle of about 45. A greater angle, say or even approaching the right angle, may be employed, and gas may be caused to flow in the tube from the exterior `to the interior, from the nozzle to the interior, or from the nozzle to both the interior and the exterior, depending upon the type of pressure zone established in the tube.

The pipe or tube I2 need not be of greater diameter than required for convenience in passing the spray head I3, or for whatever purpose the aperture is intended, and should be relatively long as compared with its diameter. It is desirable that the nozzle I-'I be located at least one diameter of the pipe I2 from either end, and it is preferable that it be located several diameters from the end opening into the chamber.

It will be understood, of course, that more than one nozzle may be employed suitably spaced about the periphery of the pipe I2, and that any suitable maniiolding device may be used to supply iiuid to the several nozzles and to impart any particular motion to the iluid desired. It will also be understood that various parts may be made of stoneware, glassware, steel, metal alloys, or other materials of construction according to the severity of exposure 'and corrosive conditions obtaining. It will also be understood that, while I have described my invention with particular application to Water sprays in lead chamber systems, it has more general utility and may also be applied to acid recirculation lutes or apertures designed merely for inspection or sampling of the contents of lead chamber and like apparatus operated under like positive pressure, e. g., less than about 0.075 pound per square inch.

I claim:

1. In a lead chamber system means whereby access may be had to the interior of a lead chamber Without egress of noxious fumes which comprises in combination with a wall of said chamber of an open ended tube provided with a removable closure and sealed in an aperture in said wall in a manner such that access may be had from the outside into the interior of the chamber, and fluid pressure curtain means for establishing a zone of pressure in said tube which is positive with respect to the operating pressure of said system. v

2. In a closed system operating at a positive pressure less than 0.075 pound per square inch gauge, the combination with a wall of said system of means for providing access to the interior thereof comprising an open ended tube relatively long as compared with its diameterV having one end opening into the interior of said system and the other end opening to the atmosphere, said last named end being adapted to be closed by a removable closure, and means for so directing fluid into said tube as to olset the positive pressure in said system whereby access may be had to the interior of said system without egress of gas therefrom.

3. In a lead chamber system for the manufacture of sulfuric acid means whereby access may be had to the interior of a lead chamber without egress of noxious fumes which comprises in combnation with a Wall of said chamber of removable closure means for an aperture in said wall so arranged that when said closure means is removed noxious fumes in said chamber may escape through said aperture into the atmosphere, and means for establishing a fluid pressure curtain across said aperture which is positive with respect to the operating pressure of said system whereby when said closure means is removed access may be had to the interior of the system without the atmosphere becoming conn taminated with noxious fumes.

CARL E. ANDERSON.

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