Liquid purification or separation – Processes – Making an insoluble substance or accreting suspended...
Patent
1994-11-29
1996-05-28
Dawson, Robert A.
Liquid purification or separation
Processes
Making an insoluble substance or accreting suspended...
423220, 4235764, 422168, 261 84, 2102211, 2102212, 210704, 210758, 210787, 2105123, C01B 1716, B01D 2126
Patent
active
055208185
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to method and apparatus for effecting gas-liquid contacting, for example, for the removal of components from gas streams, in particular by chemical conversion or removal of gaseous components while in contact with a liquid phase or slurry, or for the removal of components from a liquid phase, in particular, for the chemical conversion or removal of components from a liquid phase while in contact with the gaseous phase.
BACKGROUND TO THE INVENTION
Procedures for effecting contact between a gas phase and a liquid phase have been devised for a variety of purposes, for example, to remove a component from the gas or liquid phase. In this regard, many gas streams contain components which are undesirable and which need to be removed from the gas stream prior to its discharge to the atmosphere or to further processing. One such gaseous component is hydrogen sulfide, while another such component is sulfur dioxide.
Hydrogen sulfide occurs in varying quantities in many gas streams, for example, in sour natural gas streams and in tail gas streams from various industrial operations. Hydrogen sulfide is odiferous, highly toxic and a catalyst poison for many reactions and hence it is desirable and often necessary to remove hydrogen sulfide from such gas streams.
There exist several commercial processes for effecting hydrogen sulfide removal. These include processes, such as absorption in solvents, in which the hydrogen sulfide first is removed as such and then converted into elemental sulfur in a second distinct step, such as in a Claus plant. Such commercial processes also include liquid phase oxidation processes, such as Stretford, LO-CAT, Unisulf, SulFerox, Hiperion and others, whereby the hydrogen sulfide removal and conversion to elemental sulfur normally are effected in reaction and regeneration steps.
In Canadian Patent No. 1,212,819 and its corresponding U.S. Pat. No. 4,919,914, the disclosure of which is incorporated herein by reference, there is described a process for the removal of hydrogen sulfide from gas streams by oxidation of the hydrogen sulfide at a submerged location in an agitated flotation cell in intimate contact with an iron chelate solution and flotation of sulfur particles produced in the oxidation from the iron chelate solution by hydrogen sulfide-depleted gas bubbles.
The combustion of sulfur-containing carbonaceous fuels, such as fuel oil, fuel gas, petroleum coke and coal, as well as other processes, produces an effluent gas stream containing sulfur dioxide. The discharge of such sulfur dioxide-containing gas streams to the atmosphere has lead to the incidence of the phenomenon of "acid rain", which is harmful to a variety of vegetation and other life forms. Various proposals have been made to decrease such emissions.
A search in the facilities of the United States Patent and Trademark Office with respect to gas-liquid contacting procedures has revealed the following United States patents as the most relevant to the present invention:
______________________________________ U.S. Pat. No. 2,274,658
U.S. Pat. No. 2,294,827
U.S. Pat. No. 3,273,865
U.S. Pat. No. 4,683,062
U.S. Pat. No. 4,789,469
______________________________________
U.S. Pat. Nos. 2,274,658 and 2,294,827 (Booth) describe the use of an impeller to draw gas into a liquid medium and to disperse the gas as bubbles in the liquid medium for the purpose of removing dissolved gaseous materials and suspended impurities from the liquid medium, particularly a waste stream from rayon spinning, by the agitation and aeration caused by distribution of the gas bubbles by the impeller.
The suspended solids are removed from the liquid phase by froth flotation while the dissolved gases are stripped out of the liquid phase. The process described in this prior art is concerned with contacting liquid media in a vessel for the purpose of removing components from the liquid phase by the physical actions of stripping and flotation.
These references contain no discussion or suggestion
REFERENCES:
patent: 2274658 (1942-03-01), Booth
patent: 2294827 (1942-09-01), Booth
patent: 2659691 (1953-11-01), Gislon et al.
patent: 3273865 (1966-09-01), White
patent: 3341450 (1967-09-01), Ciabatttari et al.
patent: 3647069 (1972-05-01), Bailey
patent: 3796678 (1974-03-01), Sen
patent: 3911093 (1975-10-01), Sherif et al.
patent: 3915391 (1975-10-01), Mercade
patent: 3925230 (1975-12-01), Koeptle et al.
patent: 3979282 (1976-09-01), Cundy
patent: 3993563 (1976-11-01), Degner
patent: 4009251 (1977-02-01), Meuly
patent: 4036942 (1977-07-01), Sibeud et al.
patent: 4255262 (1981-03-01), O'Cheskey et al.
patent: 4442083 (1984-04-01), Canales et al.
patent: 4452766 (1984-06-01), Pike
patent: 4525338 (1985-06-01), Klee, Jr.
patent: 4534952 (1985-08-01), Rapson et al.
patent: 4552747 (1985-11-01), Goar
patent: 4576708 (1986-03-01), Oko et al.
patent: 4618427 (1986-10-01), Venas
patent: 4648973 (1987-03-01), Hultholm et al.
patent: 4649032 (1987-03-01), Snavely, Jr. et al.
patent: 4666611 (1987-05-01), Kaelin
patent: 4683062 (1987-07-01), Krovak et al.
patent: 4737272 (1988-04-01), Szatkowski et al.
patent: 4789469 (1988-12-01), Cvitas et al.
patent: 4808385 (1988-02-01), Grinstead
patent: 4824645 (1989-04-01), Jones et al.
patent: 4889701 (1989-12-01), Jones et al.
patent: 4919914 (1990-04-01), Smith et al.
patent: 4959183 (1990-09-01), Jameson
"Development of Self-Inducing Dispenser for Gas/Liquid and Liquid/Liquid Systems" by Koen et al, Proceedings of the Second European Conference on Mixing, 30th Mar.-1st Apr. 1977.
"Outokumpu Flotation Machines" by K. Fallenius, in Chapter 29 of Flotation, ed. M. C. Fuerstenau, AIMM, PE Inc, New York 1976.
"Flotation Machines and Equipment" in Flotation Agents and Processes, Chemical Technology Review #172, M. M. Ranney, Editor, 1980.
Chemical Abstracts, vol. 81, No. 8, 1974, (Columbus, Ohio, US), p. 242, abstract 41073s & JP, A, 7385475 (Tabata Kagaku Co. Ltd) 13 Nov. 1973.
Ellenor David T. R.
Harbinson John N.
Smith James W.
Apollo Environmental Systems Corp.
Dawson Robert A.
Reifsnyder David A.
The University of Toronto Innovations Foundation
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