US5064763A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Biological process for purifying waste air
Assignee: BASF Corp
•
Filing: 1989-03-27
•
Granted: 1991-11-12
•
Expires: 2009-03-27
Abstract
Abstract The application relates to a process for the biological disposal and purification of waste air which is contaminated with hazardous substances with the aid of biofilters. The breakdown efficiency of the biofilter is increased by adding to the waste air basic compounds which are in the form of a gas or dissolved.
Inventors
- 👤 Rolf Bentz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:28
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/74; B01D53/84; B01D53/85; Y; Y02; Y02A; Y02A50/00; Y02A50/20
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
58 words
A process for the biological disposal and purification of waste air which is contaminated with organic solvent fumes with the aid of biofilters, wherein a basic compound, or mixture of basic compounds, which is in the form of a gas and/or is dissolved in a solvent is added to the contaminated waste air before entry into a biofilter.
Claim 2
Dependent Claim
58 words
A process for the biological disposal and purification of waste air which is contaminated with organic solvent fumes with the aid of biofilters, wherein a basic compound, or mixture of basic compounds, which is in the form of a gas and/or is dissolved in a solvent is added to the contaminated waste air before entry into a biofilter.
Claim 3
Dependent Claim
29 words
A process according to claim 1, wherein the contaminated waste air is moistened with water or water vapour, and the basic compound is added before and/or after the moistening.
Claim 4
Dependent Claim
28 words
A process according to claim 1, wherein the contaminated waste air is moistened with water or water vapour, and the basic compound is added at the same time.
Claim 5
Dependent Claim
20 words
A process according to claim 1, wherein the contaminated waste air is moistened with a basic compound dissolved in water.
Claim 6
Dependent Claim
15 words
A process according to claim 1, wherein the solvents used are organic solvents or water.
Claim 7
Dependent Claim
22 words
The process according to claim 1, wherein alkali metal and/or alkaline earth metal hydroxides and/or nitrogen-containing compounds are used as basic compounds.
Claim 8
Dependent Claim
17 words
The process according to claim 6, wherein ammonia, ammonium compounds and/or amines are used as basic compound.
Claim 9
Dependent Claim
22 words
The process according to claim 7, wherein ammonia or aqueous ammonia is added to the waste air after or during the moistening.
Claim 10
Dependent Claim
44 words
The process according to claim 1, wherein the basic compound is metered in depending on the pH, with the pH being measured in the biofilter, in the condensate, in the waste water and/or in the purified waste air after it emerges from the biofilter.
Claim 11
Dependent Claim
45 words
The process according to claim 1, wherein the contaminated waste air is passed through a separate buffer which is located upstream and/or downstream of the moistening device, upstream and/or downstream of the device for introducing the basic compounds, or else between several biofilters where appropriate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-11-11 | 1995-05-13 | 1995-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-11 | 1999-05-13 | 1999-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-11 | 2003-05-13 | 2003-11-12 | $7700.00 | Window Closed / Lapsed |