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US4704972A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for reducing acid pollutants in smoke

Assignee: Sogea SA
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Filing: 1987-01-13
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Granted: 1987-11-10
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Expires: 2007-01-13
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Abstract

Abstract A method and apparatus for reducing the amount of water-soluble acid pollutants contained in hot smoke or fumes produced by combustion, such as the incineration of household garbage, in the course of which dust is removed from the smoke and the smoke is then cooled before being released into the atmosphere. A heat exchange process involving a cold fluid is used in the cooling phase, in which the smoke is cooled to a temperature below its dew point so that the resulting total or partial condensation of the water vapor contained in the smoke traps acid pollutants.

Inventors

  • 👤 Denis Marchand

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 08:55
CPC Classifications
B; B01; B01D; B01D5/00; B01D5/0003; B01D5/0009; B01D5/0078; B01D5/0093; B01D53/00; B01D53/002; F; F23; F23J; F23J15/00; F23J15/06; F23L; F23L15/00; F23L15/04; F23J2219/00; F23J2219/70; F23J2900/00; F23J2900/15004; Y; Y02; Y02E; Y02E20/00; Y02E20/34; Y02P; Y02P70/00; Y02P70/10

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 132 words
A method for reducing the amount of water-soluble acid pollutants contained in hot smoke produced by combustion means (1; 101), comprising the steps of: (a) removing dust from said smoke (31; 110), (b) cooling the smoke to a temperature below a dew point thereof so that water vapor contained therein condenses and traps acid pollutants, said smoke being cooled by passing it through a heat exchanger (4) in thermal communication with a cold fluid in a descending vertical path, (c) collecting and draining off the condensate (43, 9) for neutralization of the acid pollutants trapped therein with a reagent (10, R), (d) passing smoke exiting the heat exchanger through means (61) for trapping remaining condensate droplets carried by the smoke, and (e) releasing smoke exiting the trapping means to the atmosphere (7).
Claim 2
Independent Claim 132 words
A method for reducing the amount of water-soluble acid pollutants contained in hot smoke produced by combustion means (1; 101), comprising the steps of: (a) removing dust from said smoke (31; 110), (b) cooling the smoke to a temperature below a dew point thereof so that water vapor contained therein condenses and traps acid pollutants, said smoke being cooled by passing it through a heat exchanger (4) in thermal communication with a cold fluid in a descending vertical path, (c) collecting and draining off the condensate (43, 9) for neutralization of the acid pollutants trapped therein with a reagent (10, R), (d) passing smoke exiting the heat exchanger through means (61) for trapping remaining condensate droplets carried by the smoke, and (e) releasing smoke exiting the trapping means to the atmosphere (7).
Claim 3
Dependent Claim 37 words
The method of claim 1, wherein, after dust removal and before cooling in the heat exchanger, the smoke is initially cooled (104) to a temperature higher than a highest dew point of acidic substances in the smoke.
Claim 4
Dependent Claim 22 words
The method of claim 2, wherein the temperature of the smoke after said initial cooling is between 130° C. and 180° C.
Claim 5
Dependent Claim 13 words
The method of claim 2, wherein said initial cooling is implemented using water.
Claim 6
Dependent Claim 62 words
The method of claim 1, wherein the cold fluid is air which, after being heated through thermal contact with the smoke in the heat exchanger, is separated into two fractions, a first of said fractions being mixed with cooled smoke during its release to the atmosphere, and a second of said fractions being conveyed to the combustion means as supplementary combustion air.
Claim 7
Independent Claim 164 words
An apparatus for reducing the amount of water-soluble acid pollutants contained in hot smoke produced by combustion means (1; 101), comprising: (a) means (31; 100) for removing dust from said smoke, (b) a heat exchanger (4) coupled to an outlet of the dust removing means for cooling the smoke to a temperature below a dew point thereof such that water vapor contained therein condenses and traps acid pollutants, (c) means (43, 9) operatively associated with the heat exchanger for collecting and draining off the condensate for neutralization of the acid pollutants trapped therein with a reagant (R), (d) devesiculator means (61) coupled to an outlet of the heat exchanger for trapping remaining condensate droplets carried by the smoke, and (e) a smokestack (7) coupled to an outlet of the devesiculator means for discharging treated smoke to the atmosphere, wherein: (1) air is forced through the heat exchanger as a coolant, and (2) the heat exchanger defines a vertically descending flow path for the smoke.
Claim 8
Independent Claim 164 words
An apparatus for reducing the amount of water-soluble acid pollutants contained in hot smoke produced by combustion means (1; 101), comprising: (a) means (31; 100) for removing dust from said smoke, (b) a heat exchanger (4) coupled to an outlet of the dust removing means for cooling the smoke to a temperature below a dew point thereof such that water vapor contained therein condenses and traps acid pollutants, (c) means (43, 9) operatively associated with the heat exchanger for collecting and draining off the condensate for neutralization of the acid pollutants trapped therein with a reagant (R), (d) devesiculator means (61) coupled to an outlet of the heat exchanger for trapping remaining condensate droplets carried by the smoke, and (e) a smokestack (7) coupled to an outlet of the devesiculator means for discharging treated smoke to the atmosphere, wherein: (1) air is forced through the heat exchanger as a coolant, and (2) the heat exchanger defines a vertically descending flow path for the smoke.
Claim 9
Dependent Claim 54 words
The apparatus of claim 6, further comprising a further heat exchanger (104) interposed between the dust removing means and said heat exchanger, a recuperative boiler (2) comprising part of the combustion means, and means (105, 108, 21) for circulating water as a cooling fluid through said further heat exchanger and said boiler, in succession.
Claim 10
Dependent Claim 25 words
The apparatus of claim 6, further comprising a wet dust-scrubber (62) interposed immediately downstream from the heat exchanger (4) and upstream from the devesiculator means.
Claim 11
Dependent Claim 18 words
The apparatus of claim 6, wherein the combustion means (101) comprises an incinerator of household refuse or garbage.

References Cited (Backward Citations)

US3726239A Cited
US4019444A Cited
US4285282A Cited
US4309947A Cited
US4651655A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-11-09 1991-05-11 1991-11-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-11-09 1995-05-11 1995-11-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-11-09 1999-05-11 1999-11-10 $7700.00 Window Closed / Lapsed

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