Liquid purification or separation – Processes – Treatment by living organism
Patent
1997-05-28
1998-12-22
Wyse, Thomas G.
Liquid purification or separation
Processes
Treatment by living organism
210620, 210627, 210631, 210192, 2101951, 210205, C02F 178, C02F 330, C02F 132
Patent
active
058513990
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a process according to the preamble of claim 1 and a corresponding plant according to the preamble of claim 10.
The invention relates to the treatment and disposal of water-borne pollutants which can be degraded only with difficulty, or not at all, in a purely biological manner, e.g. toxic substances in leachates from landfills or industrial effluent such as chlorinated hydrocarbons, dioxins, pesticides or dyestuffs.
It is customary to treat industrial effluent and landfill leachates of this type by a combination of biological treatment and ozonization, in order to achieve the legally prescribed values for introduction into a sewage outfall for COD (=chemical oxygen demand), BOD.sub.5 (=biological oxygen demand), AO.sub.x (=absorbable organic halogenated hydrocarbons) and NH.sub.4 --N (=ammonium nitrogen). For this purpose, conventional unpressurized activated sludge biological treatments or pressurized vessel biological treatments using activated sludge or film biological treatments fixed on support materials are used. Attempts are made to oxidize completely, with ozone, the substances which are not biodegraded in these treatments to give biodegradable acids or carbon dioxide. An ozone treatment of this type which can be connected downstream of a biological treatment is subject matter of EP 478 583 B1.
In order to save energy, it is also known to give the nonbiodegraded substances only a preliminary cracking with ozone and then to feed them to a downstream biological step where a further biodegradation process takes place which can then deal with the preliminarily cracked substances which were not biodegraded in the first biological stage. Plants of this type are operated by the applicant in the harbors of Amsterdam and Rotterdam in order to treat industrial effluent in such a manner that they can be introduced into the sewage outfall.
The combinations of preliminary biological treatment, ozonization and downstream biological treatment in various vessels and stages gives rise to large overall dimensions. In addition, the circulating water streams for the upstream and downstream biological treatment and ozonization are circulated and operated separately. This also gives rise to high energy costs for the pumps. The biological treatments are customarily supplied with atmospheric oxygen, energy again being necessary to operate the gas introduction apparatus, i.e. the compressors. If the biological treatments are supplied with industrial-grade oxygen, it is also already known to react the industrial-grade oxygen in a separate system to generate the ozone required for the ozonization and then, that is to say when the ozone is no longer present, to use it for the biological treatment. However, in this case also, the oxygen which was not converted into ozone and not absorbed by the circulating water of the plant, is collected separately and resupplied to the ozone generator, as is given by, for example, EP 478 583, FIG. 3, for which purpose pump power and plant components are required.
The preambles of claims 1 and 10 are based on DE 40 00 292 A1, which relates to a process for purifying water which is polluted with poorly degradable compounds, using ozone, in which prepurified water is subjected to an ozonization at an ozone concentration such that only a preliminary oxidation of the poorly degradable compounds present in the water takes biodegradation by microbiologically colonized activated carbon. An adequate efficiency of the ozonization requires in this case a complex multistage reaction vessel arrangement.
The object of the invention is to eliminate the disadvantages of the prior method which are high capital expenditure for vessels and equipment units and high energy expenditure for the water circuits to supply the biological treatment and the separate water circuits for the ozone introduction and ineffective oxygen utilization.
This object is achieved in its processing aspect by the invention given in claim 1.
A biological treatment and an ozone treatment are again combined here,
REFERENCES:
patent: 3847803 (1974-11-01), Fisk
patent: 4256574 (1981-03-01), Bhargava
patent: 4824563 (1989-04-01), Iwahori et al.
patent: 5240600 (1993-08-01), Wang et al.
patent: 5645725 (1997-07-01), Zitzelsberger et al.
Patent Abstracts of Japan, vol. 950, No. 003, JP 7-080481, Mar. 1995.
Patent Abstracts of Japan, vol. 018, No. 371, JP 6-099188, Apr. 1994.
Patent Abstracts of Japan, vol. 950, No. 004, JP 7-088495, Apr. 1995.
Derwent Publications Ltd., Class D15, AN 95316272, JP 7-214093, Aug. 1995.
Chemical Patents Index, Derwent Publications, Ltd., Ref. No. 94-205360/25, JP 6-142695, Nov. 1992.
H. U. Baldes, "Aufbereitung von Deponiesickerwasser mit Ozon aus Sauerstoff", WLB Wasser, Luft und Boden, Apr. 1993, p. 54.
Lehr-und Handbuch der Abwassertechnik; 3 Aufl., Bd. IV, Verlag Ernst & Sohn, Berlin, 1985, p. 311.
Chemical Patent index, Derwent Publications, Ltd., Ref. No. 90-315580/42, JP 2-222798, Feb. 1989.
Wedeco Umwelttechnologie Wasser-Boden-Luft GmbH
Wyse Thomas G.
LandOfFree
Process and arrangement for biodegrading pollutants in water does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process and arrangement for biodegrading pollutants in water, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process and arrangement for biodegrading pollutants in water will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2042461