US2788959A

US2788959A - Spherodizer

Info

Publication number: US2788959A
Application number: US496361A
Authority: US
Inventors: John C Sherwin
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-03-23
Filing date: 1955-03-23
Publication date: 1957-04-16
Anticipated expiration: 1974-04-16

Description

United States Patent sr-nnngonlzan John C..Sherwin, Soutl1-San FranciscmrCalifi, assignor to the Unitedstates of America as represented by'the Secretary ofrthe Navy Application March- 23, 1955; Serial No.496',361

3 Claims. (Cl. 263-21) (Granted under Title 35, U. S. Code-(1952), sec; 266) This invention may be manufactured and used by or for the Government of the United States of America for governmental purposes withoutthe payment of any royalties thereon or therefor.

This invention relates to aerosol apparatus, and more particularly to an apparatus for producing an aerosol sample containing spherical particles.

In conducting laboratory radioactive contaminationdecontamination scale studies, it is, necessary to provide aerosol samples simulating the actual particulate matter orfall-out produced by an underground-orshallow underwater atomic explosion. It has been determinedth'at such radioactive particles are glassy spheres in an environment of inert particles.

Several difierent types of apparatus have been proposed for this purpose but, generally speaking, they have involved the handling of large quantities oflow activity materials as well as excessive number of'steps in the making, collecting and mixingofgradioactive spheres with the gross material. Further, these procedures entail the necessity for storing the mixture until used.

A principal object of thisinvention is to provide a single apparatus which willproduce an aerosol sample of spherical particles and acorollary object is to simultaneously mix the sphericalparticles with a second particulate matter to produce a desired aerosol.

Another object is to provide such an apparatus in which the cycle of operation is continuous.

Further objects are to provide an apparatus which is simple and inexpensive in initial cost and operation.

These and other objects will become apparent from the detailed description and the accompanying drawing.

The foregoing objects of this invention are accomplished by an apparatus generally comprising a combustion chamber in which can be formed radioactive spherical particles, the particles then being mixed with another particulate matter and the mixture discharged from the apparatus.

In one specific embodiment, the apparatus is formed of inner and outer concentrically spaced open-ended tubular members having an annular passage therebetween through which is propelled an inert particulate matter. The inner tube is a combustion chamber being provided with a flame producing means into which is introduced a second particulate matter capable of being melted and formed into spherical particles. The inner tube extends short of the mouth of the outer tube to form a chamber for mixing the inert particulate matter and the spherical particles, the latter particles being formed as they are drawn through the combustion chamber and subsequently discharged from the apparatus in the mixture.

In the drawing, Fig. l is a side elevation of the assembled apparatus constructed according to the invention; Fig. 2, a longitudinal section of the apparatus, and Fig. 3, an enlarged transverse section taken along line IH-Ill of Fig. 1.

Referring to the drawing, the apparatus, which is gen- 2,788,959 Patented, Apr. 16, 1957 2: erally indicated. by the numeral,10,.comprises apair. of inner and. outer open-ended. tubular. members. 12 and .14, connectedtogether inzspacedconcentric. relation. by, webs 16. To provide a carrier for the radioactive...spherical particles laterv to. be: described, an..inert, non-radioactive particulatematter represented by arrow. 17, is.introduced under pressure into passages..18.through-a-hose.20i and subsequently expelled froma .tube-nozzles22.in,a, mixture with. the. radioactive particles: representedzby. arrow .23..

Inner. tube; 12 constitutes a chamber. whereradioactive spherical. particles are..,formed. in. a. heating and cooling process, onesuitable heating. meansbeinga conventional oxy-acetylene torch24, having oxygen.andacetylenepipes 26. and'28- projectingthroughzouter. tube-14. As sucli;a flame, will produce temperatures of. approximately- 60.00? F., it is. preferred thatinner. tube. 12.be. constructed. of stainless steeland. provided. with cooling finsv 29. A powder cuttingadapter is threadedly. mounted arounrl a torch nozzle 32, and the nozzle assembly; is seatedin the rearend of inner tube 12. The. bore. of adapter30 is con: centricallyspaced from .nozzle 32.forrprovidingdischarge passages. 34 about nozzle. jets..36. Passages 34, which, in reality, are a series ofzradially-spacedholes, are com-r municated, with a suitable sourceof radioactive particulate matter, not shown, this matter being carrie'dzbyan oxygen stream and ejected from passages. ;34linto thecorn-bust-ion chamber in the direction of arrowsSSw The. radioactive matter may be a mixture :of soil particles andanyxradioactive material to be tested, ,thesoil particles capable of beingmelted in the oxy-acetyleneflame; The gas mixture discharged into inner tube 12 -from. nozzle jets36 is ig'- nitable by a spark plug 39connectedto asuitablexsource of, power, such as abatteryv 40 anda. transformer 42' (Fig. 1)

The radioactive matter. inthe illustrated embodiment is introduced into thecombustiorn chamber in .the. same. general direction as the oxy-acetylene. gases, and1it-.is. apparentthat the particles have a straightiflow through the flame as they are. being melted and ,formed .into. spherical particles. However, if it is desired to melt larger sized particles than normally could be accommodated with the above assembly, this can be accomplished by introducing the particles in a counterflow to the oxyacetylene gases, in which case the particles would be propelled into the flame and after propelling force has been dissipated they would reverse their path and flow concurrent with the flame. Thus, the larger particles would remain in the hottest position of the flame for a longer period of time and would have more opportunity to melt.

Although operation of the apparatus probably is obvious from the drawing, it will be briefly described. After the oxy-acetylene flame has been properly set and the inner tube 12 has attained a red heat, the flow through pipe 20 is initiated. The inert non-radioactive material flow 17 is propelled through passages 18 and discharged from nozzle 22. Simultaneous with the above flow, the radioactive particles in flow 37 are ejected into the flame through passages 34 and are heated above their melting point in transit through the combustion chamber so that, upon leaving the hot area of the flame they solidify into spherical particles. When the radioactive spherical particles reach the end of the inner tube 12, they are mixed in chamber 44 formed between the end of tube 12 and tube 14 and finally they are discharged through nozzle 22. with the inert material. The discharged material can be directed in any manner depending on the type of contamination-decontamination studies to be conducted.

The foregoing apparatus enables the formation of spherical particles, the mixing of these particles and dispersion of the mixture, all in a simple and expeditious manner. These operations are carried on in a continuous cycle eliminating separate and independent operations, and the stowage of intermediate mixtures.

Obviously, many modifications and variations of the present invention are possible in the light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced'otherwise than as specifically described.

I claim: 1 V

1. Apparatus for forming and mixing particulate matter comprising an outer tubular member having inlet and outlet ends, 'a material supply means coupled to said inlet end for introducing a particulate matter into the member and propelling it through said outlet end, an inner tubular member concentrically disposed in spaced relationship within said outermember for forming an annular passageway for said material, said inner member terminating short of said outer member discharge end for providing a mixing chamber formed by the portion of said outer member extending beyond said inner member, said portion converging into a discharge funnel of substantially the cross-sectional area of the inner member, said inner member opening into said mixing chamber and having its other end closed, flame-producing means mounted in said closed end, and a second material supply means communicated with said inner tubular member for delivering a second particulate matter into said member, said flame being capable of coalescing meltable matter into spheres prior to discharge into said mixing chamber, whereby said spheres are discharged from said chamber in an atmosphe're of the particulate matter propelled through said outer tubular member.

7 2. Apparatus for forming and mixing particulate matter comprising an outer tubular member having inlet and outlet ends, a material supply means coupled to said inlet end for introducing a particulate matter into the member and propelling it through said outlet end, an inner tubular member concentrically disposed in spaced relationship within said outer member for forming an annular passageway for said material, said inner member terminating short of said outer member discharge end for providing a mixing chamber formed by the portion of said outer member extending beyond said inner member, said portion converging into a discharge tunnel of substantially the cross-sectional area of inner member, said inner member opening into said mixing chamber and having its other end closed, flame-producing means mounted in said closed end, and a second material supply means mounted in said closed end concentrically about said flame-producing means for delivering a second particulate matter into said inner tubular member, said flame being capable of coalescing meltable matter into spheres prior to discharge into said mixing chamber, whereby said spheres are discharged in an atmosphere of the particulate matter propelled through said outer tubular member.

3. Apparatus for forming and mixing particulate matter comprising an outer tubular member having inlet and outlet ends, a supply of particulate matter, means for introducing said particulate matter under pressure into said inlet end and propelling it through said outlet end, an inner tubular member concentrically arranged in spaced relationship within said outer member for forming an annular passage for said material, said inner member terminating short of said outer member discharge end for providing a mixing chamber formed by the portion of said outer member extending beyond said inner member, said portion converging into a discharge funnel of substantially the cross-sectional area of said inner member, said inner member opening into said mixing chamber and having its other end closed, flame-producing means mounted in said closed end, a second supply of particulate matter, a second material supply means communicating said second supply with said inner tubular member concentrically about said fiame-producing means for introducing into said inner member said second particulate matter, said flame being capable of coalescing meltable matter into spheres prior to discharge into said mixing chamber, whereby said spheres are discharged in an atmosphere of said particulate matter propelled through said outer chamber.

References Cited in the file of this patent UNITED STATES PATENTS 2,536,742 Hammond Jan. 2, 1951 2,619,776 Potters Dec. 2, 1952 2,642,273 Dube June 16, 1953 Johnson et al. Apr. 25, 1950