Foul air eliminator

BACKGROUND OF INVENTION

1. Field of the Invention

This invention is a device for removing odors from air. More particularly, the invention relates to a self-contained device having a converter that chemically reduces malodor to innocuous compounds.

2. Description of the Related Art

Since the dawning of the modern age many people have at one time or another contemplated ways to cope with or eliminate malodorous air and ammonia that arises during use of the contemporary toilet. A number of methods have been employed for this purpose. These include burning candles, use of incense, opening windows, switching on overhead fans, spraying fragrances, use of elaborate toilet bowl designs and so on. These methods are ineffective, a nuisance to implement or too costly to install. Apart from the invention described herein, a single product, which is safe, effective and economical in dealing with this problem, has not emerged. Past solutions may have acted to ameliorate foul air to a limited degree, but they did so in a circuitous fashion—by rerouting the flatus or hiding it with fragrances and the like. Previous approaches do not target the fundamental cause of the trouble. The direct method of addressing this problem lies in the chemistry associated with the malodorous components themselves.

In contrast to fecal matter, tissue fluid, blood or other bio-fluids, the body of knowledge on the biochemical events giving rise to the formation of flatus is scant. Furthermore, there is not a single source that deals with the subject in a thorough fashion. Information on the compositional aspects of flatus taken from varied sources reveals the physiology and chemistry to be relatively plain. However, eliminating its negative properties affords a challenge. Flatus arises from aerophagia (swallowed boluses of air), gas diffusion (e.g. carbon dioxide) from the blood, bacterial production in the lumen, descending and sigmoid colons and from trace quantities of non-gaseous components carried with the flatus by mass transfer during expulsion. Swallowed air accounts for a large portion of nitrogen, oxygen and carbon dioxide, while diffusion from gas gradients contributes much of the remaining carbon dioxide and nitrogen portions. Methane, hydrogen, hydrogen sulfide (as well as a small amount of mercaptan) and carbon dioxide result from bacterial fermentation of residual ingesta at the point of the lumen and at locations further down in the alimentary tract. The trace non-gases are primarily heterocyclic amines from protein-rich ingesta. Specifically, the two amino acids, proline and tryptophan can lead to pyrrole and indole (C4H5N and C8H7N respectively) derivatives subsequent to deamination/decarboxylation of the parent molecules. Nitrogen from deamination is nearly quantitatively converted to ammonia and later to urea in a formal condensation with carbon dioxide in vivo. Energy from that transformation is captured and stored in lipid form as ATP for later use in the body. The remaining moieties of the proline and tryptophan precursors are readily converted in vivo to pyrrole and indole nuclei respectively. Both of these materials are thermodynamically stable owing to their aromaticity, but this is especially germane in the case of indole and its derivatives, which are resistant to further catabolic breakdown. Its structural integrity and associated physical-chemical properties are preserved while in the body. Consequently, indole is believed to be more ubiquitous in flatus among the general population, and the only alkaloid of appreciable significance in flatus. Even so the majority of this non-gaseous component will be eliminated as—is in fecal matter rather than flatus. The only other relevant constituent in flatus is low molecular weight carboxylic acid (butyric acid for example) that is generated from enzyme hydrolysis of ester oils. Flatus components and their approximate relative abundance are depicted below.

TABLE 1

[t1]

Major (and coincidentally odorless) Components of Flatus

Flatus Concentration Constituent Range

Oxygen 0-10%

Hydrogen 5-35%

Methane 0-30%

Carbon Dioxide 5-50%

Total Minor Comp. (Table 2) <1%

TABLE 2

[t3]

Minor (and coincidentally malodorous) Components of Flatus

Flatus Concentration Constituent Range (parts per million)

Indoles 0.5-10 ppm

Hydrogen Sulfide 0.5-10 ppm

Pyrroles <10 ppm

Carboxylic Acids 1-100 ppm

Mercaptans <0.1 ppm

Miscellaneous trace

It is to be noted that there is variation in flatus for individuals between expulsions as well as variation between individuals within the general population as a whole. For example, one third of the population produces no methane. This is why only ranges for flatus components are given.

The major components (Table 1) are present at a strength that is orders of magnitude greater than the minor ones (Table 2). The sum of all minor components in flatus seldom exceeds 1%. However, the most interesting aspect of flatus composition is that there is no major component which is malodorous—and there is no minor component which is not malodorous. Thus, as it is the principal intent of this invention to eliminate the experience of foul air exposure, it was only necessary to address problems created by the minor components (Table 2), and to a lesser extent, ammonia from urination. Indoles, pyrroles, carboxylic acids and most mercaptans are not gases at ambient or in vivo conditions. These four minor components, therefore, are susceptible to capture by activated charcoal. Indeed, in prior art, cited herein, a few previous inventors have incorporated the use of activated charcoal in their apparatuses. These devices were undoubtedly successful in removing these four substances, at least to a limited degree.

On the other hand activated charcoal cannot be used to mitigate hydrogen sulfide, contrary to numerous efforts and claims of the past. The mechanism for adsorption by activated charcoal involves, in sequence, condensation, Van der Walls attraction and capillary action to the interior core of the charcoal particle, at or near the boiling point of the intended substrate. With a boiling point of less than −60° C., hydrogen sulfide cannot undergo even the first step of the adsorption process unless it is taking place under cryogenic conditions.

As ambient conditions are not conducive to this adsorption process, it would be advantageous to devise an alternative method for removing hydrogen sulfide, within the operating parameters to be found in the user environment.

SUMMARY OF INVENTION

The invention lies in a self-contained foul air eliminator comprising a housing having an intake port, an exhaust port, an impeller, and a converter. The converter includes an oxidizing agent or a hydro-sulfur labile compound in an amount sufficient to effectively react with malodorous compounds in air driven by the impeller from the intake port to the exhaust port through the converter. The converter further includes an aqueous solution of a promoter carried by a support in a position to accelerate the reaction between the oxidizing agent or hydro-sulfur labile compound and the malodorous compounds.

Preferably, the housing contains a power source such as a battery to render it portable. For example, it can be mounted to a toilet. A foul air eliminator according to the invention can also have the housing adapted to connect to a 120-volt household current to drive the impeller. Preferably, the impeller operates in a range of 20 SCFM to 150 SCFM. In another aspect, eliminator can have a fragrance repository between the converter and the exhaust port.

BRIEF DESCRIPTION OF DRAWINGS

In the drawings:

FIG. 1

is a perspective view of a converter element with an oxidizing agent according to the invention;

FIG. 2

is a perspective view of another embodiment of a two-tiered converter containing oxidizing agent, Lewis base and Lewis acid according to the invention;

FIG. 3

is a perspective view of a three-tiered converter according to the invention;

FIG. 4

is a schematic diagram of a foul air eliminator according to the invention;

FIG. 5

is a schematic diagram of an alternative embodiment of a foul air eliminator according to the invention;

FIG. 6

is an elevational view of a foul air eliminator according to the invention;

FIG. 7

is a perspective view of an alternate embodiment of a foul air eliminator according to the invention; and

FIG. 8

is a perspective view of a further embodiment of the foul air eliminator according to the invention.

DETAILED DESCRIPTION

This invention includes two sub-units. The first sub-unit is referred to herein as the “converter” (or “converting system”). It is that part of the device, which contains the agents that chemically change ammonia from urination and odoriferous components in flatus to non-malodorous substances. The second sub-unit is referred to herein as the “gas-handler” (or “gas-handling system”). It delivers the foul air to the converter for alteration and discharges the malodor-free air that results. In addition, the two systems are integrated in a manner that introduces efficiency to the overall process.

1. Converter

Referring to

FIG. 1

at the heart of the invention is a converter

100

. It generally consists of a zone of the agent used for the chemical conversion of the odor causing substances. In the depicted embodiment of

FIG. 1

, flexible fabric

102

is impregnated with an agent

104

, or agents. The fabric must be chemically resistant to the conversion agent, or agents, and porous enough to allow the air stream delivered by the gas-handler to smoothly pass through it (0.1 SCFM or higher) when making contact with the converter chemical. It is essentially a membrane that is positioned in the converter in such a way that the foul air can not escape without first making contact with the agent.

The area of the incident surface varies. For example, effective bathroom models have had areas of two to six square inches. The surface area can be larger in units that have more demand, such as a hospital unit (see FIG.

7

). A variation of this membrane design is a packed column containing beads impregnated with converter agent. In either case the foul air is forced to make contact with chemical agents in the converter. The converter is a modular unit that can be easily removed and replaced when needed.

Hydrogen sulfide and, to a lesser extent, mercaptans, are the only odor-causers, other than ammonia from urination, that require chemical conversion. The other malodorous components can be dealt with in a manner well known in the art. The sulfur compounds are transformed into non-volatile and non-odorous compounds when they are reacted with various oxidizers. Therefore, in its simplest form the conversion chemical may consist only of an oxidizing agent—particularly if removing hydrogen sulfide is the only objective. This simplest approach does in fact have merit. The reason is that hydrogen sulfide is the most egregious of the malodorous components. It is toxic and detectable by the human olfactory system at extremely low levels (typically parts per billion). Moreover, current theory on nerve receptor site mechanics holds that both primary and secondary receptor nerves are capable of detecting multiple numbers of different substances, and that in order for a nuisance odor to be experienced, a certain threshold number of these sites must be triggered directly or indirectly. It may well be that for most of the population, simply eliminating the odor owing to the hydrogen sulfide could sufficiently reduce the total impact of the entire group of malodorous components, so that the nuisance threshold is not reached. This would mean a commercial goal of eradicating the unpleasant experience could be achieved by using only an oxidizing agent in this device in most instances. Thus, at a minimum, the converter fabric has a single oxidizing agent applied to it.

For daily use on a given commode over a three month period, the minimum quantity of oxidizing agent required for effective operation of this invention varies from 0.1 grams to 10 grams depending on the molecular weight, particle size and reactivity of the oxidizing agent used. The reason that such a small quantity of reagent is needed is that the amount of malodorous components being converted are so miniscule. Indeed, the longevity of the converter module depends more on the intramolecular degradation tendencies of the specific reagents being used than on the load level of the malodorous components during use.

In some instances the oxidizing agent must first be adsorbed on a support before impregnation on the fabric. In other cases it can be used neat—or on a support. A useful support can be any chemically resistant adsorbent material including, but not limited to, precipitated silica, fumed silica, diatomaceous earth, inert elastomeric pellets, vermiculite, natural or synthetic zeolites or alumina. Common oxidizing agents that are effective in this device are listed below (Table 3). Mixtures of these materials in different ratios are also effective.

TABLE 3

Common oxidizers useful for conversion of hydrogen sulfide

[t2]

1. Sodium dichloroisocyanuric acid.

2. Potassium dichloroisocyanuric acid.

3. Sodium trichloroisocyanuric.

4. Potassium trichloroisocyanuric.

5. Potassium permanganate.

6. Sodium permanganate.

7. Sodium hypochlorite in wet solvent.

8. Potassium hypochlorite in wet solvent.

9. Hypochlorous acid in wet solvent.

10. Calcium oxide.

11. Magnesium oxide.

12. Chromium trioxide.

13. Manganese dioxide.

14. Chromium trioxide-pyidine complex.

15. Lead tetraacetate.

16. Barium oxide.

17. Cadmium oxide.

18. Lead oxide.

19. Strontium oxide.

20. Mercury oxide.

21. Chromic acid.

22. Hydrogen peroxide - wet.

23. Sodium peroxydicarbonate.

24. Potassium peroxydicarbonate.

25. Metachloroperbenzoic acid.

26. Trifluroperacetic acid.

27. Trichloroperacetic acid.

28. Perbenzoic acid.

29. Potassium chromate.

30. Sodium chromate.

31. Sodium metaperiodate.

32. Potassium metaperiodate.

33. Copper oxide.

34. Cobalt oxide.

35. Osmium tetroxide.

36. Titanium dioxide.

37. Tungston oxide.

38. Diatomic halogens (iodine, chlorine, bromine and fluorine).

In addition, there are numerous, more exotic agents that also effectively oxidize hydrogen sulfide (and mercaptans) in this device. These are indicated below (Table 4) and cross referenced with CAS numbers.

TABLE 4

Exotic oxidizers useful in this invention

[t4]

CHEMICAL

CAS #

CROSS-REF

tert-BUTYLPEROXY

[26748-

NEODECANOATE

41-

4]

tert-BUTYL

[26748-

PEROXYNEOHEPTANOATE

38-

9]

tert-BUTYLPEROXY OCTOATE

[13467-

tert-BUTYL

82-

PEROCTOATE

8]

tert-BUTYL

[0-0-

PEROXYPHENOXYACETATE

0]

3-tert-BUTYLPEROXY-3-

[25251-

PHENYLPHTHALIDE

51-

8]

tert-BUTYLPEROXY PIVALATE

[927-7-

1]

tert-BUTYLPEROXY iso-PROPYL

[2372-

CARBONATE

21-6]

tert-BUTYLPEROXY STEARYL

[0-0-

CARBONATE

0]

tert-BUTYLPEROXY o-TOLUATE

[22313-

62-

8]

tert-BUTYLPEROXY-3,5,5-

[13122-

TRIMETHYLHEXANOATE

18-

4]

O,O-tert-BUTYL-O-iso-

[0-0-

PROPYL PEROXYCARBONATE

0]

CHLOROPEROXYBENZOIC ACID

[0-0-

0]

3-CHLOROPEROXYBENZOIC

[937-

m-CHLOROPER-

ACID

14-4]

BENZOIC ACID

9(11),22-CHOLESTADIEN-

[0-0-

24b-METHYL-5,8-PEROXY-

0]

3b-OL ACETATE

6,9(11),22-CHOLESTATRIEN-

[0-0-

24b-METHYL-5,8-PEROXY-

0]

3b-OL ACETATE

6,9,(11),22-CHOLESTATRIEN-

[0-0-

24b-METHYL-5,8-PEROXY-3b-

0]

OL 3-ACETATE

COPPER (II) OXYACETATE

[52503-

63-

6]

COPPER OXYCHLORIDE

[1332-

40-7]

COPPER (II) OXYCHLORIDE

[1332-

COPPER

40-7]

OXYCHLORIDE

COPPER OXYCHLORIDE

[0-0-

SULFATE

0]

TRIMETHYLCYCLOHEXANE

[6731-

1,1-BIS(tert-

36-8]

BUTYLPEROXY)-

3,3,5-TRIMETHYL-

CYCLOHEXANE

DICETYL PEROXY

[26322-

DICARBONATE

14-

5]

DICYCLOHEXYL PEROXY

[1561-

DICARBONATE

49-5]

DI-2-ETHOXYETHYL

[52373-

PEROXYDICARBONATE

74-

7]

DI(2-ETHYLHEXYL)

[16111-

PEROXYDICARBONATE

62-

9]

2,5-DIHYDROPEROXY-2,5-

[3025-

DIMETHYLHEXANE

88-5]

2,4-DIHYDROXY-2-METHYL-

[0-0-

4-HYDROPEROXYPENTANE

0]

DIMETHOXY-iso-

[0-0-

PROPYLPEROXYDICARBONATE

0]

2,5-DIMETHYL-2,5-BIS(tert-

[78-63-

2,5-DIMETHYL-2,5-

BUTYLPEROXY)HEXANE

7]

DI(tert-BUTYL-

PEROXY)HEXANE

2,5-DIMETHYL-2,5-BIS(tert-

[0-0-

BUTYLPEROXY) HEX-3-YNE

0]

2,5-DIMETHYL-2,5-BIS(2-

[13052-

2,5-BIS(2-

ETHYLHEXOYLPEROXY)HEX-

9-0]

ETHYLHEXANOYL-

ANE

PEROXY-2,5-

DIMETHYLHEXANE

2,5-DIMETHYL-2,5-DI

[2618-

(BENZOYLPEROXY)HEXANE

77-1]

2,5-DIMETHYL-2,5-DI(tert-

[78-63-

BUTYLPEROXY)HEXANE

7]

2,5-DIMETHYL-2,5-DI(tert-

[1068-

2,5-DIMETHYL-2,5-

BUTYLPEROXY)-3-HEXYNE

27-5]

DI(tert-BUTYL-

PEROXY)HEXYNE-3

2,5-DIMETHYL-2,5-DI(tert-

[0-0-

BUTYLPEROXY)HEXYNE

0]

2,5-DIMETHYL-2,5-DI(tert-

[1068-

BUTYLPEROXY)HEXYNE-3

27-5]

2,5-DIMETHYL-2,5-DI(2-

[13052-

2,5-BIS(2-

ETHYLHEXANOYL PEROXY)

9-0]

ETHYLHEXANOYL-

HEXANE

PEROXY-2,5-

DIMETHYLHEXANE

DI-(3-METHYL-3-METHOXY

[0-0-

BUTYL)PEROXYDICARBONATE

0]

DIMYRISTYL

[53220-

PEROXYDICARBONATE

22-

7]

DI(PROPYL)

[16066-

PEROXYDICARBONATE

38-

9]

DI-iso-PROPYL

[105-

PEROXYDICARBONATE

64-6]

ETHYL-3,3-BIS(tert-

[55794-

ETHYL 3,3-DI(tert-

BUTYLPEROXY)BUTYRATE

20-

BUTYLPER-

2]

OXY)BUTYRATE

ETHYL 3,3-DI(tert-

[55794-

BUTYLPEROXY)BUTYRATE

20-

2]

2-ETHYLHEXYL

[1611-

PEROXYDICARBONATE

62-9]

HYDROGEN PEROXY-SULFURIC

[0-0-

UREA

0]

1-[(1-

[78-18-

HYDROPEROXYCYCLOHEXYL)

2]

DIOXY]CYCLOHEXANOL

1-

[12262-

CYCLOHEXANONE

HYDROPEROXYCYCLOHEXYL-

58-

PEROXIDE

1-HYDROXY CYCLOHEXYL

7]

PEROXIDE

13(S)-

[33964-

HYDROPEROXYOCTADECA-

75-

9Z,11E-DIENOIC ACID

9]

13(S)-HYDROPEROXY-

[0-0-

9Z,11E,15Z-

0]

OCTADECATRIENOIC ACID

MAGNESIUM

[84665-

MONOPEROXYPHTHALATE

66-

7]

MAGNESIUM

[78948-

PEROXYPHTHALATE

87-

5]

MAGNESIUM

[0-0-

PEROXYPHTHALATE

0]

HEXAHYDRATE

MONOPEROXYPHTHALIC ACID,

[78948-

MAGNESIUM SALT

87-

5]

MONOPEROXYPHTHALIC ACID

[84665-

MAGNESIUM SALT

66-

HEXAHYDRATE

7]

p-NITROPEROXYBENZOIC ACID

[943-

4-NITROPER-

39-5]

BENZOIC ACID

OXOPEROXYMOLYBDENUM

[23319-

OXOPIPEROXY-

(PYRIDINE)

63-

MOLYBDENUM

HEXAMETHYLPHOSPHOR-

3]

(PYRIDINE)

AMIDE

HEXAMETHYL-

PHOSPHORAMIDE

OXOPIPEROXYMOLYBDENUM

[23319-

(PYRIDINE)

63-

HEXAMETHYLPHOSPHOR-

3]

AMIDE

PEROXYACETIC ACID

[79-21-

PERACETIC ACID

0]

PEROXYDICARBONATE

[34099-

48-

4]

PEROXYDISULFURYL

[13709-

FLUORIDE

32-

5]

PEROXYDOL

[0-0-

0]

PEROXYKETAL, CYCLIC

[0-0-

0]

PEROXYMONOSULFURIC ACID

[0-0-

0]

PEROXYNITRITE

[14042-

1-4]

PEROXYNITRITE,

[157167-

TETRAMETHYLAMMONIUM

78-

SALT

7]

POTASSIUM

[15593-

PEROXYDIPHOSPHATE

49-

4]

POTASSIUM PEROXYDISULFATE

[7727-

POTASSIUM

21-1]

PERSULFATE

POTASSIUM PEROXY

[0-0-

MONOSULFATE

0]

iso-PROPYL-sec-

[0-0-

BUTYLPEROXYDICARBONATE

0]

SODIUM CARBONATE

[0-0-

PEROXYHYDRATE

0]

SODIUM PEROXYCARBONATE

[4452-

58-8]

SODIUM PEROXYDISULFATE

[7775-

SODIUM

27-1]

PERSULFATE

TETRAKIS(PYRIDINE)SILVER (II)

[15810-

PEROXYDISULFATE

50-

1]

TETRAPOTASSIUM

[0-0-

PEROXYDIPHOSPHATE

0]

2,4,4-TRIMETHYLPENTYL-2-

[0-0-

PEROXYNEODECANOATE

0]

2,4,4-TRIMETHYLPENTYL-2-

[0-0-

PEROXYPHENOXYACETATE

0]

VINYL TRIS(tert-BUTYLPEROXY)

[15188-

SILANE

9-7]

Yet a third type of material that can be reacted with hydro-sulfur compounds (hydrogen sulfide and mercaptans) can be referred to as “hydro-sulfur labile” compounds. These materials are organic substances possessing functional groups that can form products resulting form nucleophilic addition. For example, phthalic anhydride is effective at a level of one gram in a standard unit (see FIG.

6

). Other organic functional groups that serve as hydro-sulfur labile compounds to react and convert the sulfur-containing malodorous components of flatus are indicated below:

TABLE 5

Hydro-sulfur labile converter functional groups

[t5]

1. Carboxylic acid anhydrides

2. Olefins

3. Alkynes

4. Carboxylic acid esters

5. Aldehydes

6. Isonitriles

7. Alkyl halides

8. Alpha diketones

9. Acyl halides

10. Diazo ketones

11. Epoxides

12. Isocyanates

13. Isothiocyanates

14. Thiocyanates

15. Vinyl ethers

16. Diazonium salts

17. Alpha-beta unsaturated carbonyls

18. Ketones

19. Alpha-beta unsaturated nitriles

20. Metal hydrides

21. Carbamates

Interestingly, in addition to being capable of reacting with certain sulfur compounds, some of the reagents listed act as disinfectants as well. In particular, sodium dichloroisocyanuric acid and sodium hypochlorite have been proven to be be effective for this purpose.

For a more effective version of this appliance the carboxylic acid and amine (indoles and pyrroles) portions of flatus needed to be addressed as well. Activated charcoal can theoretically capture these materials. But unfortunately, the adsorbed species can be desorbed if the temperature in the room where the device is located should rise for any reason. Thus, as implied earlier, any device solely employing activated charcoal will end up emitting odor after a certain period of use. To avoid this, the carboxylic acids and amines, including ammonia from urination, must also be chemically converted to non-volatile substances rather than merely adsorbed. Unlike in the case of hydrogen sulfide and mercaptans, neither oxidation nor nucleophilic addition can be used for this purpose. However, carboxylic acids can be converted to non-volatile salts with a Lewis base. Analogously, the amines can be made into salts with a Lewis acid. But because Lewis acids and bases are not compatible, only one or the other can be impregnated along with the sulfur compound converter (Tables 3, 4 and 5) on a single piece of converter fabric. Thus the need for separate agent-bearing zones. Thus, referring to

FIG. 2

, a version of the converter

200

that targets all malodorous components includes a laminar structure consisting of two layers of fabric

202

,

204

. Because the transformation of carboxylic acids and amines to their corresponding conjugate salts is a facile process, nearly any Lewis base

206

and nearly all Lewis acids

208

can be used. For strictly practical reasons readily available commodities are preferred. Thus, useful base converters include, but are not limited to, sodium carbonate, sodium bicarbonate, Calcite, potassium carbonate etc. Useful acid converters include ascorbic acid, aspartic acid, phenol, citric acid, maleic acid, oxalic acid succinic acid and so on.

During the course of developing this device, two secrets were discovered that marginally improved the effectiveness of the converter. The first was that when aqueous solutions of certain materials pre-adsorbed on a support (such as silica or others—vide supra) were mixed with select chemical converting reagents prior to being applied to the converter fabric, the performance of the converter was boosted. These materials (Table 6), referred to herein as “promoters,” are linked by common features.

TABLE 6

Promoters used to enhance converter performance

[t6]

1. Tergitol

R

9.5 from Union Carbide.

2. Alfonic

R

Nonionic from Vista Chemical Co.

3. JL 80X nonionic from Huntsman.

4. Polyethylene glycol.

5. Polypropylene glycol.

6. Glucan P-20 from Amerchol.

7. Cetyl range ethoxylated nonionic.

8. Lauryl range ethoxylated nonionic surfactant.

The promoters cited are all water-soluble ethylene oxide or propylene oxide oligimers. They have inverse cloud points owing to their propensity to complex with water. Since solvent-solute kinetics are intrinsically more favorable than gas-solid kinetics, the enhanced performance is undoubtedly due to the presence of the bound water. In short, any water-soluble ethylene oxide or propylene oxide derivative, or mixtures of such, will have this beneficial effect to some degree, depending on the identity of the converter agents it is blended with and the degree to which it is capable of binding with water.

The second thing learned related to the use of activated charcoal. Even though it is not especially effectual when used by itself, some performance synergy is realized when it is used to complement the actual converter chemicals. Activated charcoal is not compatible with oxidizing agents, so the two cannot be blended together. But when a zone of charcoal is positioned upstream, it acts as a sort of holding reservoir for foul air components, which can release malodorous components to the converter chemicals at a later point in time. This is important in instances when the converter would otherwise be swamped by a heavy flux of malodorous air. Therefore, referring to

FIG. 3

, an adaptation of the two-tiered version of the converter includes a third tier carrying an activated charcoal. The three-tiered adaptation

300

therefore includes two fabric layers

302

,

304

, corresponding to the layers of

FIG. 2

, and an activated charcoal layer

310

.

The converter fabric itself can be formed out of nearly any flexible cloth or mat material—including fordriniered pulp, woven, semi-woven, natural fiber, synthetic fiber, high rag content paper or felt, which is at least somewhat resistant to chemical degradation and is of sufficient porousity to allow a minimum air flow rate of 0.1 SCFM. This is true for two reasons: 1) the converter chemicals used are generally not especially reactive or harsh. 2) Any destructive aptitude they possess is severely modulated by their relatively low concentration. For example, half-inch nylon fiber mat with nominal 25-micron pore size works as well as one inch polypropylene fiber mat with 100-micron pore size. The number and kinds of different fabric materials (or porous beads in the case of a packed column arrangement) that can be successfully employed in fabricating the converter appears to be limitless.

2. Gas Handler

Referring now to

FIGS. 4 and 5

, the gas handling system is merely a collection of support elements required to channel malodorous gas to the converter so it can be made benign. Although some type of gas handling system is described in all prior art, in no case has it been connected to a chemical converter, which is essential to the successful operation of the appliance.

Specifically, the gas-handler

400

includes an intake

402

, impeller

404

, exhaust port

406

, power source

408

, and housing

410

.

Housing

410

communicates between the intake

402

and the exhaust

406

, carrying the impeller

404

and the converter

300

, as depicted schematically (see FIG.

4

). Since the only requirement is to deliver the malodorous air to the converter for alteration, there is an inherent flexibility in the way some of the elements can be arranged and scaled. For example, it matters not whether the impeller is positioned downstream from the converter (

FIG. 5

) or upstream from it (FIG.

4

)—although in practice, the upstream location afforded better flow in most cases. Also, an enlarged version of the device accommodates more demanding applications. Use around bedpans in hospital rooms and in surgery rooms have been identified as areas where a larger version of this invention would be of value. In all these cases, however, the converter and all five elements of the gas-handling system are optimal. With the converter having already been explained, each element of the gas-handler will be discussed presently.

In order for the converter to function properly, a majority of the malodorous gas must first be collected. This is accomplished by means of intake

402

, including a port

1

leading to a hollowed flange

2

mounted on the sides and/or back of the toilet bowl during installation (FIG.

6

). The intake port(s)

1

, hollow flange

2

or combination thereof is the point of entry of the malodorous gas into the gas-handling system. In the case of a flush toilet they are located at or near the level of the toilet bowl rim. Air flow is generated by impeller

404

. Owing to the relatively short distance the air travels, especially when the intake port

402

is mounted toward the back of the bowl, there is minimal flow resistance. Accordingly, the required flow rate is governed primarily by the volume of flatus to be removed during a single expulsion. Physiological data reveal that this volume is rarely greater than 300 ml (and more typically 150 ml). Furthermore, volume expansion resulting from movement to a lower pressure environment (˜1 atm.) is not greater than 15%. From this data a volume of 200 ml can be established as a benchmark (i.e. applicable in >90% of the cases). When this is coupled with a factor for diffusion time (e.g. diatomic oxygen gas diffusion coefficient=0.178 cm2/sec at 00 C.), we arrive at a required flow rate of around 67 ml/sec. After converting units we get approximately 0.10 to 0.15 SCFM. Thus, 0.1 SCFM was computed as the minimum effective impeller flow rate for this invention.

It was learned that a large variety of impellers (fans, blowers and so on) were capable of efficiently delivering flow rates far in excess of 0.1 SCFM. Two-sided intake blowers were particularly attractive in experimental models owing to their shape. The impeller may be optionally activated by means of either a pressure sensitive actuator (set nominally for 20 pounds), or a manual control button. In either case the switch communicates with the power source and impeller (blower) through an electrical lead housed within the unit itself. In practice, impellers rated for around 20 SCFM were found to work well. The number of impellers commercially available that can deliver a flow rate in this neighborhood is staggering. Ones that have the following rating options all work satisfactorily in this invention:

[t7]

Parameter

Range

Flow, SCFM

1-100

RPMs

100-5000

Power, watts

5-100

Voltage

3-240

Current, amps

0.2 min

The exhaust

406

is the opening by which the purified air escapes the handler

400

and reenters the room (FIG.

6

). However, it is apparent that the escaping purified air possesses kinetic energy, which can theoretically be utilized. For example, a modular fragrance repository

14

can be placed at the exhaust port

406

so that the exhaust energy can be used to introduce a pleasant scent into the air during use of the invention. Though this appliance obviates the need for this option, its inclusion is prudent from a commercial standpoint.

The relatively diminutive flow rate requirements make it possible for power source

408

to be either a battery or a wall outlet (120 volt or 240 volt). It is housed within the unit itself in the case of the former. Model work demonstrates that a 12 volt battery can operate for six to eight weeks with regular daily use of this device before replacement is needed. Thus, there is considerable leeway for selecting sources of power to be incorporated into this invention. Independent of the source of power, the switch mechanism that activates whatever power source is in place can be selected from a variety of options. Among them are:

[t8]

1. Pressure actuator switch

2. Manual switch

3. Infrared trigger type

4. Radio frequency type

Flatus, though unpleasant, is neither hazardous nor corrosive. And since, by design, the chemical reagents housed in the converter never make direct contact with the gas-handling system, materials of construction of the gas-handler is not a troublesome issue. The only requirements are that they be machinable, semi-rigid to hold shape and have enough longevity to be practical. Therefore, a large array of materials can be used in fabricating this invention—including, but not limited to, the following:

t9]

1) Stainless steel

2) Aluminum

3) Carbon steel

4) PET

5) PVC

6) Polystyrene

7) High density polyethylene

8) LDPE

9) Polypropylene

10) Polycarbonate

11) ABS resin

12) Phenol formaldehyde resin

13) Wood

14) Particle laminate

15) Thermosetting resins

16) Thermoplastics

17) Polyvinyl actetate

18) Partially hydrolyzed polyvinyl acetate

19) Polyacrylonitrile

20) Polyacrylic ester

21) Caplan

R

22) Kevlar

R

23) Sheet metal

In addition, the flexibility engendered by the overall invention design affords the potential of manufacturing all or portions of the gas-handling system by injection, or blow molding methodologies.

Referring to

FIG. 6

, the intake port

1

is located under the lid of the toilet. It communicates with the rest of the unit by means of the hollow flange

2

. As the invention is being used, it may be activated by the manual switch

3

. The foul air flows through the intake port and hollow flange by means of the pressure differential created by the in-line impeller

4

. The impeller is a 3000 rpm, 20 SCFM blower powered with 11 Watts, by a 12 volt, 900 milliamp battery

5

through contacts

6

and leads

7

. The battery also communicates with the manual switch

3

by means of the electrical leads

8

. The impeller also communicates with the switch through the impeller leads

9

.

The housing

10

is PVC. The overall length is 15 inches. The width is approximately 5.5 inches at its widest point. The battery is located near the bottom on the interior of the unit and is secured with adhesive and a truncated PVC flange just large enough to hold it. The flange extends laterally toward the center. It is positioned against one side so air flow is not obstructed. The unit sits up off the floor with a clearance

11

of approximately two inches. Its weight is supported by means of a hook-shaped fastener

12

that curves over and under the toilet bowl rim. The fastener

12

is an extension of the lower surface of the intake port. The exhaust port

13

is approximately six square inches and is fitted with a fragrance repository

14

composed of a scent absorbed onto a piece of porous felt that is roughly the same size as the exhaust port opening.

Turning now to the converter

15

, the illustrated embodiment is the more advanced three-tiered version described earlier (

FIG. 3

) with a total lateral surface area of approximately 20 square inches. It is supported by means of an interior PVC lip that extends to the interior of the device toward the center. It is around {fraction (3/32)} inches wide and runs along the entire interior circumference of the device at its widest point. The composition of the converter is as follows:The first layer of the embodiment of the converter is a half-inch thick polypropylene fiber mat that is supporting 25 grams of 40 mesh activated charcoal.

The second layer of the converter in this embodiment is another half-inch thick piece of fiber mat impregnated with 75 grams of the following formula:

[t10]

1.

15% Sodium dichloroisocyanuric acid.

2.

8% of 5% Sodium hypochlorite solution.

3.

18% Sodium bicarbonate (Lewis base).

4.

18% Alfonic

R

nonionic surfactant.

5.

39% Ultrasil

R

precipitated silica.

6.

2% Partially hydrolyzed polyvinyl acetate.

The third layer is yet another half-inch thick mat that was impregnated with 25 grams of the following formula:

[t11]

1. 45% Citric acid.

2. 20% Alfonic

R

nonionic surfactant.

3. 35% Ultrasil

R

precipitated silica.

The top two layers rest on the bottom one, which is in turn supported by the PVC lip described earlier. This unit operated successfully for eight weeks before the battery required changing.

EXAMPLE 2

Referring again to

FIG. 6

, an alternate embodiment has the intake port

1

located under the lid of the toilet. It communicates with the rest of the unit by means of the hollow flange

2

. As the invention is used, it is activated by the pressure switch

16

. The foul air flows through the intake port and hollow flange by suction created by the in—line impeller

4

. The impeller was a 3000 rpm, 20 SCFM impeller receiving power from a 120 volt outlet (not shown). The power also communicates to the pressure switch by means of electrical leads

18

. The impeller also communicates with the switch through the impeller leads

9

.

The housing

10

is PVC. The overall length is 15 inches. The width is approximately 5.5 inches at its widest point. The battery is located near the bottom on the interior of the unit and is secured with adhesive and a truncated PVC flange just large enough to hold it. The flange extends laterally toward the center. It is positioned against one side so air flow is not obstructed. The unit sits up off the floor with a clearance

11

of approximately two inches. Its weight is supported by means of a hook-shaped fastener

12

that curves over and under the toilet bowl rim. The fastener

12

is an extension of the lower surface of the intake port. The exhaust port

13

is approximately six square inches and is fitted with a fragrance repository

14

composed of a scent absorbed onto a piece of porous felt that is roughly the same size as the exhaust port opening.

An alternative converter

15

is the simple one-layer design of

FIG. 1

with a total lateral surface area of approximately 18 square inches. It is supported by means of an interior PVC lip that extends to the interior of the device toward the center. It is around {fraction (3/32)} inches wide and runs along the entire interior circumference of the device at its widest point. The composition of the converter is as follows:

The mat is half-inch thick polypropylene fiber impregnated with 50 grams of the following formula:

[t12]

1. 25% Calcium Oxide.

2. 10% of 5% Sodium hypochlorite solution.

3. 25% Alfonic

R

nonionic surfactant (Promoter).

4. 40% Ultrasil

R

precipitated silica.

This unit operated with fair success for a seven weeks.

EXAMPLE 3

Referring again to

FIG. 6

, another embodiment has the intake port

1

located under the lid of the toilet. It communicates with the rest of the unit by means of the hollow flange

2

. As the invention is being used, it is activated by the pressure actuator

16

. The foul air flows through the intake port and hollow flange by means of the pressure differential created by the in-line impeller

4

. The impeller is a 3000 rpm blower powered with 11 Watts, by a 12 volt, 900 milliamp battery

5

through contacts

6

and leads

7

. The battery also communicates with the pressure switch

16

by means of the electrical leads

18

. The impeller also communicates with the switch through the impeller leads

9

.

The housing

10

is PVC. The overall length is 15 inches. The width is approximately 5.5 inches at its widest point. The battery is located near the bottom on the interior of the unit and is secured with adhesive and a truncated PVC flange just large enough to hold it. The flange extends laterally toward the center. It is positioned against one side so air flow is not obstructed. The unit sits up off the floor with a clearance

11

of approximately two inches. Its weight is supported by means of a hook-shaped fastener

12

that curves over and under the toilet bowl rim. The fastener

12

is an extension of the lower surface of the intake port. The exhaust port

13

is approximately six square inches and is fitted with a fragrance repository

14

composed of a scent absorbed onto a piece of porous felt that is roughly the same size as the exhaust port opening.

The third embodiment of the converter

15

is the two-tiered arrangement described earlier (

FIG. 2

) having total lateral surface area of approximately 20 square inches. It is supported by means of an double adhesive tape applied to the edge of the bottom layer. The first layer is one-inch thick nylon fiber mat impregnated with 85 grams of the following formula:

[t13]

1. 19% Sodium dichloroisocyanuric acid.

2. 5% of 5% Sodium hypochlorite solution.

3. 16% Potassium carbonate (Lewis base).

4. 21% Alfonic

R

nonionic surfactant (Promoter).

5. 39% Ultrasil

R

precipitated silica.

The second layer is another half-inch thick polypropylene mat that was been impregnated with 25 grams of the following formula:

[t14]

1. 50% Citric acid.

2. 20% Tergitol

R

nonionic surfactant.

3. 30% Ultrasil

R

precipitated silica.

This unit operated with excellent success for two and a half months.

EXAMPLE 4

In another model all parameters were identical with those described in the first example with the following exceptions:

[t15]

1. A 25 SCFM blower was substituted for the one described in the first

example.

2. The exhaust port was not fitted with a fragrance repository.

3. The housing was straight-walled at the bottom rather being

tapered.

4. The exhaust port was roughly twice as large.

EXAMPLE 5

In yet another model all parameters were identical with those described in the second example with the following exceptions:

[t16]

1. A 38 SCFM blower was substituted for the one described in the first

example.

2. The housing was straight-walled at the bottom rather being

tapered.

3. The exhaust port was roughly twice as large.

EXAMPLE 6

In still another model all parameters were identical with those described in the first example with the following exceptions:

[t17]

1.

A 25 SCFM blower was substituted for the 20 SCFM blower

described in the first example.

2.

The exhaust port was not fitted with a fragrance repository.

3.

The housing was straight-walled at the bottom rather being

tapered.

4.

The exhaust port was roughly twice as large.

5.

10% Potassium permanganate solution (5%) was added to the

converter.

6.

13% Calcium oxide was added to the converter.

7.

Sodium dichloroisocyanuric acid was not added to the converter

chemical mixture

EXAMPLE 7

A “heavy duty” version

20

of the present invention is shown in FIG.

7

. It is designed for use near hospital bed-pans and in operating rooms, was fabricated in a way that is conceptually identical to that described in the first example in the preferred embodiment, including an intake hose

22

and an exhaust port

24

. This model differs only in the following ways:

[t18]

1. It is dimensionally larger.

2. The in-line impeller is rated for 150 SCFM air displacement.

3. No fragrance repository is fitted in the exhaust port.

4. It is connected to a 120 volt electrical outlet 28 by connector 26.

5. The total weight of converter agent is 275 grams.

6. The unit was not tapered at the bottom.

EXAMPLE 8

Another version of the present invention

30

, shown in

FIG. 8

, rests on the floor rather than being supported by fastener

12

of FIG.

6

. The floor model

30

is conceptually identical to that described in the first example in the preferred embodiment. This model differs only in the following ways:

[t19]

1. It is straight-walled rather than tapered at the bottom.

2. It is supported by three one-inch high PVC legs 32.

3. It includes a hollow flange 34 formed as an oval where it intersects

the housing.

Solving the chemistry is the precise approach which the present invention employs. Using a chemical converter, the malodorous components undergo a chemical metamorphosis to materials that are inoffensive to the sense of smell. Basically, it singles out the malodorous components and irreversibly captures and simultaneously converts these materials to substances that are not capable of being re-released into the air to generate the foul odor experience. Fortuitously, many of the materials, which work effectively as converters, also destroy bacteria. In addition, use of this invention obviates the need for using spray canisters, which can introduce CFCs (chloroflurocarbons) that have been cited as having a potentially harmful effect on atmospheric ozone.

While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit.

Number	Name	Date	Kind
4604110	Frazier	Aug 1986	A
5454122	Bergeron	Oct 1995	A
5896591	Horan et al.	Apr 1999	A
6003157	Bruyere	Dec 1999	A
6528014	Parkhurst et al.	Mar 2003	B1

	Number	Date	Country
Parent	09/661109	Sep 2000	US
Child	10/065537		US

Foul air eliminator

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications

Field of Search

US

International Classifications

Abstract

Description

Claims

CROSS REFERENCE TO RELATED APPLICATIONS

US Referenced Citations (5)

Provisional Applications (1)

Continuations (1)