Liquid purification or separation – Processes – Treatment by living organism
Patent
1997-05-13
1999-10-05
Upton, Christopher
Liquid purification or separation
Processes
Treatment by living organism
210605, 210617, 210621, 210151, 2101951, 2102212, 210903, C02F 330
Patent
active
059618302
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to a wastewater treatment method and plant.
As used herein, the term "wastewater" includes sewage and any other contaminated water. Thus, the treatment plant may be used to treat a range of wastewaters including municipal wastewater and industrial wastewater.
The invention has as one of its aims the recycling of wastewater.
This invention has particular, but not exclusive, application to so-called "water-mining" plants for treatment of wastewater. However, the invention could also be used as an "end of pipe" facility.
The term "water-mining" refers to an approach to wastewater treatment which is fundamentally different to conventional treatments. Traditionally, wastewater has been reticulated from its source to a distant "end of pipe" treatment plant whereat the wastewater is treated and separated into a number of by-products.
One by-product is water of a grade suitable for irrigation, industrial applications and the like. However, this treated water is seldom returned to its origin due to the high cost of reticulation.
The "water mining" approach employs a smaller "community" site-specific plant which is intended to "mine" useable treated water from wastewater originating within a community which can then be used in the community from which the wastewater originates. The recycled water may be potable or may be suitable only for non-potable uses.
It will be appreciated that the water mining approach reduces the demand for the reticulation of water to the community and for the reticulation of wastewater away from the community.
It is envisaged that a number of smaller "community" plants would operate in conjunction with the "end of pipe" treatment plant. In that case, the smaller "community" plants need not be capable of treating the bulk of solids. Rather, solids and any other constituents not readily treatable or removable by the smaller "community" plant can be diverted to the "end of pipe" treatment plant. Alternatively, the community plant might be an "end of pipe" plant in its own right.
Thus, the essence of the "water mining" approach is to mine useable water from wastewater at or adjacent the location from which the wastewater originates. In addition to recycling water, the approach reduces reticulation loads and the loading on the "end of pipe" plant.
Whilst the "water mining" approach is plant intensive, it should be appreciated that the bulk of capital costs associated with a wastewater system resides in the reticulation system.
A "community" plant, as broadly described above, is preferably compact, low maintenance, unobtrusive, remotely controllable, and substantially odourless. Most preferably, it is modular and requires little site preparation.
BACKGROUND ART
Conventional modern wastewater treatments systems usually involve some form of biological nitrification and denitrification to remove ammonia from the wastewater.
In the nitrification stage, ammonia is reacted with oxygen to produce oxides of nitrogen, particularly nitrates. In the denitrification stage, the oxides of nitrogen are broken down to their constituent elements in the absence of oxygen.
Conventional wastewater treatments systems are large and do not address the requirements of a plant suitable for water mining.
DISCLOSURE OF THE INVENTION
In one aspect the invention resides in a method of treating wastewater including: remove solids by dissolved gas flotation.
The biological treatment is accelerated by the high partial pressure of oxygen whilst the subsequent pressure reduction can be synergistically employed to clarify the biologically treated wastewater.
Preferably, the method further includes: pressure to drive a filtration and/or disinfection process.
Preferably, the biological treatment under pressure includes: substantially remove ammonia.
Preferably also, the biological treatment under pressure further includes: dissolved oxygen; and substantially remove soluble oxidised nitrogen.
Alternatively, the pressurised biological treatment may be totally aerobic for BOD removal only.
REFERENCES:
patent: 3246885 (1966-04-01), Stevens
patent: 3390076 (1968-03-01), Dubach
patent: 3542675 (1970-11-01), Mail et al.
patent: 3574331 (1971-04-01), Kurosawa et al.
patent: 3576738 (1971-04-01), Duffy
patent: 3617539 (1971-11-01), Grutsch
patent: 3725264 (1973-04-01), Wheeler
patent: 3846289 (1974-11-01), Jeris et al.
patent: 4009099 (1977-02-01), Jeris
patent: 4056465 (1977-11-01), Spector
patent: 4069149 (1978-01-01), Jackson
patent: 4126544 (1978-11-01), Baensch et al.
patent: 4279754 (1981-07-01), Pollock
patent: 4315821 (1982-02-01), Climenhage
patent: 4430225 (1984-02-01), Takamatsu et al.
patent: 4696747 (1987-09-01), Verstraete et al.
patent: 4948509 (1990-08-01), Stack
patent: 5075384 (1991-05-01), Burke
patent: 5437785 (1995-08-01), Roshanravan
patent: 5484534 (1996-01-01), Edmondson
patent: 5516434 (1996-05-01), Cairo Jr. et al.
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