CA1178025A
Expired / Lapsed
CA
⏱️ 0.0 years remaining
Method for producing a pressurized oxide of sulfur
Assignee: Chemithon Corp
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Filing: 1981-11-06
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Granted: 1984-11-20
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Expires: 2001-11-06
Abstract
Abstract ABSTRACT OF THE DISCLOSURE A method for producing an oxide of sulfur using pressurized air. The pressurized air is mixed with molten sulfur at a sulfur burner to ignite and combust the molten sulfur and form a reaction mixture. The molten sulfur may be atomized. The pressurized air may be divided into two portions, one of which is preheated. The unheated pressurized air is mixed with the reaction mixture in the sulfur burner downstream of the location where the preheated pressurized air is mixed with the molten sulfur. Combustion of all the sulfur to sulfur dioxide is essentially completed within the sulfur burner, and the temperature of the gaseous mixture leaving the sulfur burner is controlled. The sulfur dioxide may then be cooled and converted to sulfur trioxide in a catalytic converter. The Moisture content of the pressurized air is reduced in a pressurized dryer upstream of the sulfur burner.
Inventors
- 👤 Burton Brooks
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-11-07 18:37
CPC Classifications
C; C01; C01B; C01B17/00; C01B17/69; C01B17/74; C01B17/76; C01B17/78; C01B17/79; C01B17/48; C01B17/50; C01B17/54; Y; Y02; Y02P; Y02P20/00; Y02P20/10; Y02P20/129
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
147 words
A method for producing sulfur trioxide gas, said method comprising: introducing molten sulfur into a confined sulfur-burning zone; introducing pressurized air having a pressure greater than about 30 psig up to about 120 psig into said confined sulfur-burning zone; combusting said sulfur and said pressurized air in said sulfur-burning zone to produce a first pres-surized mixture of pressurized sulfur dioxide and air; converting said pressurized sulfur dioxide into pressurized sulfur trioxide in a confined converting zone downstream of said sulfur-burning zone to produce a second pressurized mixture of sulfur trioxide and air; performing said converting step in three cata-lytic converting stages; cooling said pressurized mixture between the first and second of said converting stages; obtaining at least about 99% conversion in the first two of said converting stages; and obtaining greater than 99% conversion in said three converting stages without cooling between the second and third stages.
Claim 2
Independent Claim
147 words
A method for producing sulfur trioxide gas, said method comprising: introducing molten sulfur into a confined sulfur-burning zone; introducing pressurized air having a pressure greater than about 30 psig up to about 120 psig into said confined sulfur-burning zone; combusting said sulfur and said pressurized air in said sulfur-burning zone to produce a first pres-surized mixture of pressurized sulfur dioxide and air; converting said pressurized sulfur dioxide into pressurized sulfur trioxide in a confined converting zone downstream of said sulfur-burning zone to produce a second pressurized mixture of sulfur trioxide and air; performing said converting step in three cata-lytic converting stages; cooling said pressurized mixture between the first and second of said converting stages; obtaining at least about 99% conversion in the first two of said converting stages; and obtaining greater than 99% conversion in said three converting stages without cooling between the second and third stages.
Claim 3
Dependent Claim
92 words
A method as recited in Claim 1 and com-prising: cooling said second pressurized mixture of sulfur trioxide and air downstream of said converting zone; and introducing said pressurized air into an unheated, pressurized, moisture-absorbing, drying zone containing a stationary drying medium, and before said air is introduced into said sulfur-burning zone, to pro-duce dried, pressurized air having a dew point sufficient-ly low substantially to prevent, during the coolng of said second pressurized mixture, the formation of oleum in amounts having an adverse corrosive effect or an ad-verse effect in a sulfonating operation.
Claim 4
Dependent Claim
45 words
A method as recited in Claim 1 and com-prising: restricting the volume of said catalytic convert-ing stages to less than 60% of the volume required to convert the same weight amount of sulfur dioxide and handle the same weight amount of air at atmospheric pres-sure.
Claim 5
Dependent Claim
89 words
A method as recited in Claim 1 and com-prising: cooling said first pressurized mixture in a confined cooling zone located between said sulfur-burning zone and said converting zone; transporting said first pressurized mixture from said confined sulfur-burning zone to said confined cooling zone and then to said confined converting zone in transporting conduits; and restricting the volume of said transporting conduits and of said cooling zone to less than about 50% of the volume required to transport the same weight amounts of sulfur dioxide and air at atmospheric pressure.
Claim 6
Dependent Claim
31 words
A method as recited in Claim 4 and com-prising: restricting the volume of said transporting conduits and of said cooling zone to about one-third of the volume required at atmospheric pressure.
Claim 7
Dependent Claim
69 words
A method as recited in Claim 1 and comprising: preheating at least a portion of said pressurized air to a temperature above the ignition temperature of sulfur; and restricting the length of said sulfur-burning zone, and restricting the volume of said sulfur-burning zone by at least about 50%, compared to a sulfur-burning zone required to combust the same weight amounts of sulfur and air at atmospheric pressure without pre-heating.
Claim 8
Dependent Claim
26 words
A method as recited in Claim 6 and com-prising: restricting the volume of said sulfur-burning zone to about one-third of the volume required at atmos-pheric pressure.
Claim 9
Dependent Claim
69 words
A method as recited in Claim 6 and com-prising: initiating combustion of the sulfur by mixing the sulfur with said preheated portion of pressurized air, as the sulfur enters said sulfur-burning zone, to produce a reaction mixture containing sulfur dioxide; essentially completing the combustion of said molten sulfur in said sulfur-burning zone; and withdrawing said first pressurized mixture from said sulfur-burning zone into apparatus downstream of said sulfur-burning zone.
Claim 10
Dependent Claim
35 words
A method as recited in Claim 8 and com-prising: controlling the temperature of said first pres-surized mixture as it leaves the sulfur-burning zone to avoid an adverse effect upon the strength of said down-stream apparatus.
Claim 11
Dependent Claim
44 words
A method as recited in Claim 9 wherein said controlling step comprises: controlling the amounts and temperature of air and sulfur introduced into said sulfur-burning zone to provide said first pressurized mixture with a temperature in the range 800° to 1500°F (426° to 815°C).
Claim 12
Dependent Claim
22 words
A method as recited in Claim 8 wherein: said first pressurized mixture has a sulfur dioxide content in the range 3-18 vol.%.
Claim 13
Dependent Claim
30 words
A method as recited in Claim 8 and com-prising: avoiding subjecting the sulfur to the heating influence of said preheated air portion upstream of the entry to said sulfur-burning zone.
Claim 14
Dependent Claim
59 words
A method as recited in Claim 8 and com-prising: dividing said pressurized air into two portions; said preheating step being performed on one of said portions, the other of said portions remaining un-preheated; and introducing said unpreheated portion of air into said sulfur-burning zone downstream of the loca-tion therein where said preheated air portion was mixed with the sulfur.
Claim 15
Dependent Claim
80 words
A method as recited in Claim 13 wherein: said preheated air portion comprises at least the stoichiometric amount of oxygen required to convert all of said molten sulfur to sulfur dioxide and has a temperature above 475°F and below 1500°F (246° and 815°C); and said method comprises controlling the ratio of preheated to unpreheated air and the amount of sulfur to maintain said first pressurized mixture at a tempera-ture no greater than 1500°F (815°C) as it leaves said sulfur-burning zone.
Claim 16
Dependent Claim
39 words
A method as recited in Claim 8 wherein said preheating step comprises: indirectly cooling said first pressurized mix-ture with said portion of pressurized air, at a first heat exchanging zone downstream of said sulfur-burning zone, to preheat said portion.
Claim 17
Dependent Claim
118 words
A method as recited in Claim 8 and com-prising: cooling said first pressurized mixture to a predetermined temperature range at a location downstream of said sulfur-burning zone, said cooling being performed in two separate, discrete steps; one of said two steps comprising indirectly cooling said first pressurized mixture with said portion of pressurized air to preheat said portion of pressurized air and to partially cool said first pressurized mixture; and controlling the extent of said indirect cooling at said one cooling step to limit the temperature to which said portion of pressurized air is preheated so as to maintain a temperature in said first pressurized mixture at the outlet of said sulfur-burning zone no greater than 1500°F (815°C).
Claim 18
Dependent Claim
128 words
A method as recited in Claim 1 and comprising: cooling said second pressurized mixture of sulfur trioxide and air downstream of said converting zone to a temperature below about 120°F (49°C); drying said pressurized air by flowing it through an unheated, pressurized, moisture-absorbing, drying zone, containing a stationary drying medium, and before said air is introduced into said sulfur-burning zone; and pressurizing said air, before it is flowed through said drying zone, to a pressure which, as a result of said drying step produces dried, pressurized air having a dew point sufficiently low substantially to prevent, during said cooling of said second pressurized mixture below about 120°F (49°C), the formation of oleum in amounts which have an adverse corrosive effect or an adverse effect in a sulfonating operation.
Claim 19
Dependent Claim
33 words
A method as recited in Claim 17 wherein said pressurizing step comprises: pressurizing said air to a pressure which, in said drying zone, reduces the dew point of said air below -40°F (-40°C).
Claim 20
Dependent Claim
25 words
A method as recited in Claim 18 wherein said pressurizing step comprises: pressurizing said air to a pressure in the range 50 to 70 psig.
Claim 21
Dependent Claim
149 words
A method as recited in Claim 18 wherein said drying zone is of the type which, after the removal of moisture from air in said drying zone, may be regen-erated to deplete it of moisture by passing heated air and cooling air sequentially through said zone, said method further comprising: regenerating said zone by depressurizing a fraction of the pressurized air dried by said method and diverting said depressurized fraction of dry air thorugh said zone; said regenerating step being performed without heating or cooling said depressurized fraction of dry air and without employing a separate blower for said depressurized fraction of air; and maintaining (1) the energy expended to pressurize said air at less than (2) the energy required to obtain said dew point below -40°F (-40°C) when said drying zone is regenerated by passing heated air and cooling air therethrough and employing separate blowers to do so.
Claim 22
Dependent Claim
28 words
A method as recited in Claim 20 and com-prising: obtaining said fraction of dry air from another drying zone arranged in tandem with the drying zone under-going regeneration.
References Cited (Backward Citations)
No citation records indexed.
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