GB2113562A - Treatment process - Google Patents

Treatment process Download PDF

Info

Publication number
GB2113562A
GB2113562A GB08232836A GB8232836A GB2113562A GB 2113562 A GB2113562 A GB 2113562A GB 08232836 A GB08232836 A GB 08232836A GB 8232836 A GB8232836 A GB 8232836A GB 2113562 A GB2113562 A GB 2113562A
Authority
GB
United Kingdom
Prior art keywords
plates
oxygen
rotation
axis
flow
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB08232836A
Other versions
GB2113562B (en
Inventor
John Edward Porter
Colin Ramshaw
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Imperial Chemical Industries Ltd
Original Assignee
Imperial Chemical Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Imperial Chemical Industries Ltd filed Critical Imperial Chemical Industries Ltd
Priority to GB8232836A priority Critical patent/GB2113562B/en
Publication of GB2113562A publication Critical patent/GB2113562A/en
Application granted granted Critical
Publication of GB2113562B publication Critical patent/GB2113562B/en
Expired legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/02—Aerobic processes
    • C02F3/12—Activated sludge processes
    • C02F3/1278—Provisions for mixing or aeration of the mixed liquor
    • C02F3/1284—Mixing devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
    • B01F23/2331—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
    • B01F23/2331—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements
    • B01F23/23311—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements through a hollow stirrer axis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
    • B01F23/2331—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements
    • B01F23/23314—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements through a hollow stirrer element
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/233—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements
    • B01F23/2335—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the direction of introduction of the gas relative to the stirrer
    • B01F23/23352—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids using driven stirrers with completely immersed stirring elements characterised by the direction of introduction of the gas relative to the stirrer the gas moving perpendicular to the axis of rotation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/2366—Parts; Accessories
    • B01F23/2368—Mixing receptacles, e.g. tanks, vessels or reactors, being completely closed, e.g. hermetically closed
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
    • B01F27/80—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis
    • B01F27/93—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis with rotary discs
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/02—Aerobic processes
    • C02F3/12—Activated sludge processes
    • C02F3/20—Activated sludge processes using diffusers
    • C02F3/205—Moving, e.g. rotary, diffusers; Stationary diffusers with moving, e.g. rotary, distributors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
    • B01F27/05—Stirrers
    • B01F27/11—Stirrers characterised by the configuration of the stirrers
    • B01F27/115—Stirrers characterised by the configuration of the stirrers comprising discs or disc-like elements essentially perpendicular to the stirrer shaft axis
    • B01F27/1155—Stirrers characterised by the configuration of the stirrers comprising discs or disc-like elements essentially perpendicular to the stirrer shaft axis with interconnected discs, forming open frameworks or cages
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
    • B01F27/05—Stirrers
    • B01F27/11—Stirrers characterised by the configuration of the stirrers
    • B01F27/19—Stirrers with two or more mixing elements mounted in sequence on the same axis
    • B01F27/191—Stirrers with two or more mixing elements mounted in sequence on the same axis with similar elements
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/10—Biological treatment of water, waste water, or sewage

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Microbiology (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Treatment Of Water By Oxidation Or Reduction (AREA)

Abstract

The biochemical oxygen demand of aqueous waste material is reduced by contacting it with an oxygen-containing gas while the material is flowing, under centrifugal force, as a thin film across a surface. A plurality of rotary annular discs 8 are mounted within a closed chamber 3 having a central gas feed tube 14 with operatives 15. The aqueous waste passes, under centrifugal action, across the disc surface as a thin film which absorbs the gas as it issues from the apertures. <IMAGE>

Description

SPECIFICATION Treatment process This invention relates to a process for treating aqueous waste material having an oxygen demand, especially aqueous waste material which has an oxygen demand and in which a solid is suspended.
Typical aqueous waste materials which have an oxygen demand and in which a solid may be suspended include interaii2 sewage sludge and industrial waste, e.g. from food processing plants, the canning industry, fish farming, slaughterhouses, woollen manufacture, pulp, paper and board manufacture, and cotton processing.
The treatment of such aqueous waste materials to reduce their biochemical oxygen demand has traditionally been carried out in aeration units, which usually are static units in which the aqueos waste material passes over assorted contact materials while exposed to air. Such units usually are large in order to allow the relatively slow aeration to take place and to afford access to large quantities of air.
We have now found that the oxygen demand of such liquids can be substantially reduced for the expenditure of a desirably small amount of energy by treating the liquid with an oxygen-containing gas in a centrifugal gas-liquid contacting device.
Accordingly, the present invention provides a process for reducing the biochemical oxygen demand of aqueous waste material by contacting the aqueous waste material with an oxygen-containing gas, characterised in that the aqueous waste material is caused to flow under centrifugal force as a thin film across a surface and in contact with the oxygen-containing gas. Conveniently the surface is a surface of a plate mounted for rotation about an axis so as to give rise to the required centrifugal force.
The plate may be one of a plurality of plates.
The plate or plates may be disposed parallel to the axis of rotation but preferably, for increased efficiency, the plate or plates are mounted substantially transversely to the aforesaid axis, for example to form a stack of parallel plates.
The plates may be formed from any material which has the mechanical strength to withstand the stress generated in the material during use in the process of the present invention. Preferably the material is substantially resistant to attack by or reaction with the material with which it may be in physical contact. Typically, the material from which the plates are formed is a glass, ceramic or preferably a metal, more preferably a chemically resistant metal, e.g. stainless steel, nickel or titanium. It is often desirable to give the plates an appropriate surface treatment, which may be chemical, e.g.
etching, or physical, e.g. sand-blasting, to provide surfaces which are wetted by the liquid.
Whilst the plates may be flat and have generally even surfaces, preferably, for increased efficiency of the gas/liquid contacting, the plates are capable of causing perturbations in the flow of liquid film. For example, the plates may be corrugated or may have protrusions or indentations on one or both surfaces or may be perforated. The corrugations, protrusions, indentations or perforations are preferably disposed substantially transversely to the flow of the liquid across the plate surface. Thus, in the case of a stack of parallel plates mounted to rotate about an axis perpendicular to the plates, since the flow of liquid thereoverwill be in a generally radially outward direction, the corrugations, protrusions, indenta- Lions or perforations may advantageously be disposed in one or more circles concentric with the axis of rotation.Preferably the aforesaid one or more circles is or are continuous, particularly preferably it or they is or are in the form of one or more channels and more particularly preferably the one or more channels is or are substantially V-shaped. The concentric circles are preferably located at intervals of between 1 and 20 mms, especially about 10 mms.
Where a substantially V-shaped channel is present the radially outer surface of the V-shaped channel is preferably steeper than the radially inner surface thereof and more preferably the opper portion, at least, of the radially outer surface presents a continously decreasing gradient to the liquid as it emerges from the channel; such a decreasing gradient affords retention of the liquid on the surface of the plate at higher rotational speeds, where retention is desired.
Where a plurality of concentric substantially V-shaped channels are formed in a plate which is mounted in a centrifugal device used in the present invention there are preferably between 50 and 1,000 channels per metre measured in a radial direction across the plate, and preferably more than about 100 channels per metre; thus the pitch of the pattern of concentric channels, that is the distance between repeated features of the pattern, is preferably between 1 and 20 mms, more preferably less than about 10 mms. The depth of each channel is preferably between 0.2 and 5 mm, more preferably between 0.5 and 2.5 mm.
Where a plate used in the process of the present invention is of uniform thickness, the aforesaid uniform thickness is generally between 0.05 and 5 millimetres and preferably is in the range 0.5 to 1.5 millimetres.
Where a stack of concentric plates is employed in the process of the present invention the axial distance between plates is conveniently in the range 0.5 millimetres to 50 millimetres and preferably is between 1 and 10 millimetres. However, it will be appreciated that the aforesaid axial distance may be chosen in the light of the dimensions of any solid matter which is suspended in the liquid which is to be treated in the process of the present invention.
Whilst the oxygen-containing gas used in the process of the present invention may be air, i.e. the process is one of aeration, preferably the oxygencontaining gas is an oxygen-rich gas because this gives more efficient and quicker treatment and reduces the amount of any unwanted gas, e.g.
nitrogen, which has to be dissolved in the liquid. By oxygen-rich gas we mean pure oxygen or an oxygen-containing gas mixture having a proportion of oxygen greater than that of air. Preferably the oxygen content of the oxygen-rich gas is at least 80% and more preferably is in excess of 98%. The o;:"gen-nch gas may, if desired, include a small proponion of ozone or other gas which has a beneficial e#fact en the liquid being treated.
A variety of sources of oxygen-rich gas available.
Fo. exampie, pure oxygen may be supplied from an insulated vessel in which liquid oxygen is stored and passed through an evaporator prior to its introduction into the aqueous waste material. Alternatively, pure oxygen may be supplied from one or more gas storage cylinders. Oxygen-rich air may be supplied from an air separation plant operating a pressure swing adsorption-desorption cycle.
Solids which may be present in the liquid to be treated in the process of the present invention may be of fibrous character, e.g. hair, wool and cotton waste, or particulate, e.g. fat globules.
Circular plates over the surface of which the liquid flows in the process of the present invention have diameters typically in the range 25 cm to 5 metres and preferably about 1 metre.
The speed at which the plates are rotated in the process of the present invention is such that the liquid flowing across the surface of the plates is subjected to a mean acceleration, as hereinafter defined, of more than 10 metres seconds#2. Generally, as the mean acceleration is increased the rate of oxygen transfer into the liquid is increased. However, it will be appreciated that for plates of a certain diameter, loaded at a certain liquid flow rate, the power requirements of the apparatus in which the plates are mounted is proportional to the square of the speed of rotation of the plates. Thus the optimum speed at which the plates are rotated often represents a commercial balance between the desirability of a high mean acceleration and a low power requirement.
Mean acceleration am is defined by the equation:
where N is the rotational speed of the plates about the axis of rotation thereof in revolutions thereof in revolutions per minute, r, is the distance in metres from the aforesaid axis to the radially outer portion of the plates and r1 is the distance in metres from the aforesaid axis to the radially inner portion of the plates; it will be appreciated that where a plate is in the form of a disc, r, is zero.
The oxygen-containing gas in the process of the present invention may flow co-currently with or counter-currently to the flow of the liquid, It is preferred that an oxygen-rich gas is fed to the centrifugal contacting device in the process of the present invention at substantially the same rate as oxygen being removed by the treated liquid.
The liquid to be treated in the process of the present invention is preferably fed to the plates adjacent the axis of rotation and is discharged from the plates adjacent their radially outer portion.
Means to charge the liquid to the plates typically comprises a feed-pipe provided with an appropriate number of suitably disposed orifices. The liquid discharged from the plates is typically collected in a stationary housing in which the plates rotate and from which it can be, for example, returned to a convenient sewer.
Where counter-c-#rr# nt flow is employed it will be apprecistedi that means are necessary distant the axis of rotation and preferably adJacent the radially distant portion of the plates to charge the oxygencontaining gas to the plates. Conveniently the plates are mounted in a stationary housing in which they rotate, into which housing the oxygen-containing gas can be charged under a suitable pressure and hence flow between the plates.
The rate of flow of liquid across the surface of a plate is typically in the range 104 to 10-2 metres31 second/metre of plate perimeter.
The process of the present invention may conveniently be effected while the liquid is held in or while it is flowing through a sewer. For example, through a conduit connected between the sewer and the centrifugal gas-liquid contacting device used in the process of the present invention, a portion of the liquid may be fed to the gas-liquid contacting device for treatment and then returned via a second conduit to the sewer.
The term "sewer" as used in this specification includes within its scope a conduit which is connected between a source of liquid which has an oxygen demand and a treatment plant, e.g. an activated sludge or biological filtration plant or a place of disposal or collection; any pumping equipment used to transfer the aforesaid liquid through a conduit and any sump in which the aforesaid liquid is collected before being pumped through a conduit.
The process according to the present invention can be perfomed in a gravity sewer or a rising sewer.
A gravity sewer slopes downwards in the direction of the flow of sewage therethrough so that the passage of the sewage is effected by gravity. On the other hand, in a rising sewer transfer of sewage is effected by a pump. A rising sewer may comprise a conduit which follows the undulations of the ground in which it has been laid. This type of rising sewer is sometimes referred to as a pumping sewer or main, and possibly lengths of it will have a downward inclination in the direction of the flow of the sewage.
Alternatively, a rising sewer can be a cylindrical pipe which is inclined so that it rises continuously or for most of its length in the direction of flow of the sewage therealong.
In a rising sewer, the treatment may be performed in a length of conduit forming a part of the sewer, in any sump in which sewage is collected before being passed through the rest of the sewer, or in the volute of any pump used to pass the sewage through the rest of the sewer.
Flammable vapour is sometimes present in the air space above the level of liquid in a sewer. In conventional processes for treating sewage with an oxygen-rich gas, care has to be taken to ensure that substantially all the oxygen in the oxygen-rich gas has been dissolved since if undissolved oxygen entered the aforesaid air space explosive conditions could exist The process of the present invention tends to avoid the problem associated with the presence of undissolved oxygen in the sewage by affording better dissolution of the oxygen-contain ing gas.
When the process according to the present invention is applied to the treatment of sewage, the treatment may alternatively be applied at the sewage works itself, at the secondary treatment stage. It may be of particular advantage in appropriate circumstances to remove a portion of sewage, say for example 5 per cent to 30 per cent, especially about 10 per cent, from a larger volume in say a treatment bed; to subject that removed portion to the process of the present invention, especially using neat oxygen or an oxygen-rich gas; and then to return the treated portion to the main body of sewage. In this way it is possible, where an existing works is already operating at its capacity, to enhance the total capacity of the works for the relatively modest cost of a compact centrifugal device such as the present invention may employ.
The invention will now be further described by reference to the following drawings, which show a preferred apparatus for carrying out the process of the present invention. In the drawings: Figure 1 is a vertical section through a gas-liquid contacting device in which the process of the present invention can oe carried out; and Figure 2 is a horizontal section on the line A-A of Figure 1.
In the drawings, a rotor, designated generally by the numeral 1, is mounted upon a drive shaft 2, by means of which it is rotated within a chamber 3 defined by cover 4, base 5 and cylindrical sidewall 6.
Where the shaft 2 passes through the base 5 a conventional mechanical seal 7 is provided. Rotor 1 comprises a plurality of thin annular plates 8, mounted on six pins 9 on the base 10 of the rotor and spaced apart by washers 11, and a cover plate 12.
The chamber 3 is provided with a gas4eed tube 13, liquid feed-pipe 14, which has apertures 15 in its lower end, and liquid discharge port 16.
In the process of the present invention, the chamber 3 is charged with oxygen via tube 13, the rotor 1 is rotated, and the liquid to be treated in the process is fed via feed-pipe 14 and the apertures 15 to the stack of annular plates 8. The liquid moves radially outwards across the surfaces of the annular plates as a thin film, is ejected from the outer perimeter of the plates and collects in the chamber 3 from where it can be run off through discharge port 16 and returned to a sewer. The thin film of liquid absorbs oxygen as it flows across the surfaces of the annular plates and oxygen is continually replenished via the feed-pipe 13.

Claims (11)

1. A process for reducing the biochemical oxygen demand of aqueous waste material by contacting said material with oxygen-containing gas, characterised in that the aqueous waste material is caused to flow under centrifugal force as a thin film across a surface an in contact with the oxygen-containing gas.
2. A process as claimed in claim 1, in which the surface is one face of a plate mounted for rotation about an axis.
3. A process as claimed in claim 2, in which the plate is one of a plurality of plates.
4. A process as claimed in claim 2 or claim 3, in which the plate is mounted parallel to its axis of rotation.
5. A process as claimed in claim 2 or claim 3, in which the plate is mounted transverse to its axis of rotation.
6. A process as claimed in claim 5, in which the aqueous waste material is caused to flow across at least one surface of each of a plurality of plates, mounted parallel to each other transverse to thsir common axis of rotation, and some at least of said plates are capable of causing perturbations in said liquid flow.
7. A process as claimed in claim 6, in which said plates capable of causing perturbations are corrugated or have protrusions and/or indentations on at least one surface or are perforated.
8. A process as claimed in claim 7, in which said corrugations, protrusions, indentations or perforations are disposed in one or more circles concentric with the axis of rotation.
9. A process for reducing the biochemical oxygen demand of aqueous waste material which comprises feeding said material to a stack of parallel plates mounted for rotation about an axis perpendicular to said plates, rotating said plates so as to subject the material to a mean acceleration of more than 10 metres seconds~2 and thereby cause said material to flow across said plates in the form of a thin film, and bringing an oxygen-containing gas into contact with said thin film.
10. A process for reducing the biochemical oxygen demand of aqueous waste material, which process is substantially as hereinbefore described with reference to the accompanying drawings.
11. A process for reducing the biochemical oxygen demand of flowing sewage comprising diverting a portion of said sewage flow, subjecting said diverted portion to treatment by a process as claimed in any of claims 1 to 10, and subsequently combining the treated diverted portion with the undiverted portion of said sewage flow.
GB8232836A 1981-11-24 1982-11-17 Treatment process Expired GB2113562B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB8232836A GB2113562B (en) 1981-11-24 1982-11-17 Treatment process

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8135405 1981-11-24
GB8232836A GB2113562B (en) 1981-11-24 1982-11-17 Treatment process

Publications (2)

Publication Number Publication Date
GB2113562A true GB2113562A (en) 1983-08-10
GB2113562B GB2113562B (en) 1986-01-08

Family

ID=26281363

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8232836A Expired GB2113562B (en) 1981-11-24 1982-11-17 Treatment process

Country Status (1)

Country Link
GB (1) GB2113562B (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2132184A (en) * 1982-12-17 1984-07-04 Water Res Centre Biological treatment of liquids
WO1999008780A1 (en) * 1997-08-20 1999-02-25 Tva Technologies Pty Ltd Improved mixing and aerating apparatus
WO1999062608A1 (en) * 1998-05-29 1999-12-09 Norsk Hydro Asa A method for desorption of one or more compounds from an absorbent solution and use thereof
WO1999062626A1 (en) * 1998-06-01 1999-12-09 Alliance Pharmaceutical Corp. Liquid breathing-gas exchanger
US20150209741A1 (en) * 2014-01-27 2015-07-30 ProMinent Fluid Controls, Inc. Polymer Mixer
CN105800266A (en) * 2016-05-30 2016-07-27 苏州速腾电子科技有限公司 Throwing and splashing device
CN105797633A (en) * 2016-05-30 2016-07-27 苏州速腾电子科技有限公司 Diffuser
CN105817157A (en) * 2016-05-30 2016-08-03 苏州速腾电子科技有限公司 Liquid circulating device
CN105836395A (en) * 2016-05-30 2016-08-10 苏州速腾电子科技有限公司 Spraying device

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105797620A (en) * 2016-05-30 2016-07-27 苏州速腾电子科技有限公司 Diffusion device
CN105797631A (en) * 2016-05-30 2016-07-27 苏州速腾电子科技有限公司 Solution tank with diffusion device
CN105797632A (en) * 2016-05-30 2016-07-27 苏州速腾电子科技有限公司 Container with diffuser

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2132184A (en) * 1982-12-17 1984-07-04 Water Res Centre Biological treatment of liquids
WO1999008780A1 (en) * 1997-08-20 1999-02-25 Tva Technologies Pty Ltd Improved mixing and aerating apparatus
US6280078B1 (en) 1997-08-20 2001-08-28 Tva Technology Pty. Ltd. Double sided Mixing and aerating apparatus
CN1089267C (en) * 1997-08-20 2002-08-21 Tva技术有限公司 Improved mixing and aerating apparatus
WO1999062608A1 (en) * 1998-05-29 1999-12-09 Norsk Hydro Asa A method for desorption of one or more compounds from an absorbent solution and use thereof
WO1999062626A1 (en) * 1998-06-01 1999-12-09 Alliance Pharmaceutical Corp. Liquid breathing-gas exchanger
US20150209741A1 (en) * 2014-01-27 2015-07-30 ProMinent Fluid Controls, Inc. Polymer Mixer
CN105800266A (en) * 2016-05-30 2016-07-27 苏州速腾电子科技有限公司 Throwing and splashing device
CN105797633A (en) * 2016-05-30 2016-07-27 苏州速腾电子科技有限公司 Diffuser
CN105817157A (en) * 2016-05-30 2016-08-03 苏州速腾电子科技有限公司 Liquid circulating device
CN105836395A (en) * 2016-05-30 2016-08-10 苏州速腾电子科技有限公司 Spraying device

Also Published As

Publication number Publication date
GB2113562B (en) 1986-01-08

Similar Documents

Publication Publication Date Title
US3276994A (en) Sewage treatment
GB2113562A (en) Treatment process
US3650950A (en) Material shearing mixer and aerator
EP0247162B1 (en) Centrifugal oxygenator for treatment of waste water and system
EP0080311B1 (en) Contacting device
US4231863A (en) Method and apparatus for treating water
US4505820A (en) Method for cleaning waste water
US4956082A (en) Centrifugal bio-contactor apparatus
US4643852A (en) Energy efficient phase transfer/dispersion systems and methods for using the same
AU5256699A (en) Device for agitating a liquid in a reactor and for injecting a gas into this liquid
EP0629142A1 (en) Apparatus and method for treatment of waste water sludge
EP0058225B1 (en) Pressurized aeration tank for activated-sludge process sewage treatment
EP0258228A1 (en) An apparatus for the purification of water, waste water in particular, by a biological oxidation method
CA2173397A1 (en) Biochemical reactor of liquid current type, groundwater and wastewater purifying system equipped therewith, and liquid transport-stirring apparatus that employs the transport means used in said reactor and system
US5240599A (en) Apparatus for treatment of waste water sludge
US3704868A (en) Mechanical aerator
FI59825C (en) APPARATUS FOER FRAMSTAELLNING AV EN LIGNOCELLULOSAPRODUKT AV KROSSADE VAEXTRAOMATERIALIER
US4233152A (en) Apparatus and method for the treatment of liquors
US5314622A (en) Dual purpose oxygenator
JP4632630B2 (en) Biological fluid treatment device
US4108763A (en) Continuous treatment of liquid effluent and sewage
JPS59501939A (en) Method and equipment for dehydrating liquid or pasty mixtures
US5002659A (en) Arrangement for cleaning of waste water
WO1989006160A1 (en) An agitator
GB2297084A (en) Water treatment device

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee