[go: up one dir, main page]

WO2011070218A1 - Method and equipment for separating solids from slurry and use of the method and/or equipment - Google Patents

Method and equipment for separating solids from slurry and use of the method and/or equipment Download PDF

Info

Publication number
WO2011070218A1
WO2011070218A1 PCT/FI2010/000073 FI2010000073W WO2011070218A1 WO 2011070218 A1 WO2011070218 A1 WO 2011070218A1 FI 2010000073 W FI2010000073 W FI 2010000073W WO 2011070218 A1 WO2011070218 A1 WO 2011070218A1
Authority
WO
WIPO (PCT)
Prior art keywords
slurry
flocculant
mixer
helix
liquid
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.)
Ceased
Application number
PCT/FI2010/000073
Other languages
French (fr)
Inventor
Jussi Vaarno
Launo Lilja
Juhani Lyyra
Pertti Pekkala
Bror Nyman
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.)
Metso Corp
Original Assignee
Outotec Oyj
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 Outotec Oyj filed Critical Outotec Oyj
Publication of WO2011070218A1 publication Critical patent/WO2011070218A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • 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
    • B01F27/92—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis with helices or screws
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G1/00—Production of liquid hydrocarbon mixtures from oil-shale, oil-sand, or non-melting solid carbonaceous or similar materials, e.g. wood, coal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
    • B01D21/01—Separation of suspended solid particles from liquids by sedimentation using flocculating agents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
    • B01D21/02—Settling tanks with single outlets for the separated liquid
    • B01D21/08—Settling tanks with single outlets for the separated liquid provided with flocculating compartments
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
    • B01D21/28—Mechanical auxiliary equipment for acceleration of sedimentation, e.g. by vibrators or the like
    • B01D21/286—Means for gentle agitation for enhancing flocculation
    • 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
    • B01F23/50—Mixing liquids with solids
    • B01F23/53—Mixing liquids with solids using driven stirrers
    • 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
    • B01F27/114—Helically shaped stirrers, i.e. stirrers comprising a helically shaped band or helically shaped band sections
    • B01F27/1145—Helically shaped stirrers, i.e. stirrers comprising a helically shaped band or helically shaped band sections ribbon shaped with an open space between the helical ribbon flight and the rotating axis
    • 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
    • B01F27/114—Helically shaped stirrers, i.e. stirrers comprising a helically shaped band or helically shaped band sections
    • B01F27/1145—Helically shaped stirrers, i.e. stirrers comprising a helically shaped band or helically shaped band sections ribbon shaped with an open space between the helical ribbon flight and the rotating axis
    • B01F27/11451—Helically shaped stirrers, i.e. stirrers comprising a helically shaped band or helically shaped band sections ribbon shaped with an open space between the helical ribbon flight and the rotating axis 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
    • B01F27/80—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis
    • B01F27/86—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis co-operating with deflectors or baffles fixed to the receptacle
    • 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
    • B01F27/92—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis with helices or screws
    • B01F27/922—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis with helices or screws with two or more helices, e.g. with intermeshing helices
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F11/00—Treatment of sludge; Devices therefor
    • C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
    • C02F11/14—Treatment of sludge; Devices therefor by de-watering, drying or thickening with addition of chemical agents
    • C02F11/147—Treatment of sludge; Devices therefor by de-watering, drying or thickening with addition of chemical agents using organic substances
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/34—Treatment of water, waste water, or sewage with mechanical oscillations
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2301/00—General aspects of water treatment
    • C02F2301/02—Fluid flow conditions
    • C02F2301/024—Turbulent

Definitions

  • the invention relates to the method specified in the preamble of claim 1 for separating solids from slurry.
  • the invention further relates to the equipment specified in the preamble of claim 9.
  • the invention further relates to the use of the method and/or equipment as specified in claim 17.
  • Oil sand is the term used for bitumen that is bound to grains of sand. Worldwide, the amount of oil in oil sands is of the same magnitude as the amount of normal petroleum. The exploitation of oil sands on a wide scale only began in the last couple of decades of the twentieth century, because it is more difficult to utilise than conventional oil.
  • Bitumen is formed from petroleum so that the petroleum has lost its lighter hydrocarbons and the remaining heaviest part has been partially decomposed by bacteria. Thus bitumen is partially degraded petroleum. Oil sands contain 1 - 20% bitumen.
  • the grains of sand are surrounded by a layer of water, including different kinds of particulates such as clay and other minerals.
  • the bitumen film that surrounds the layer of water has to be separated from the sand, water and particulates before it can be processed further .
  • the recovery and processing of oil sands into crude oil requires more energy and money than drilling the equivalent amount of oil from conventional deposits. For this reason, the wide-scale exploitation of oil sands has not previously been profitable, but with the rise in oil price and development in technology the operation has become economically viable. It is possible that in the future, when the current sources of oil are exhausted, people will turn to the use of oil sands as the major source of crude oil.
  • the environmental impacts of refining oil sands are greater than those in conventional oil production.
  • Some slurry processing methods and equipment for separating solids from slurry containing a suspension of liquid and fine solid particles are known in the prior art in connection with oil sand refining, for example in US patents 4,225,433 and 5,645,714.
  • a quantity of liquid flocculant is added to the slurry that is substantially smaller than the amount of slurry.
  • the slurry and flocculant are mixed to form a contact between the fine solid particles and the flocculant in order to bind the fine solid particles to each other as floes.
  • the solids and liquid from the flocculated slurry are separated from one another in a separate process stage following the flocculation stage.
  • the flocculant or flocculation agent is usually a long-chain polymer, which when mixed evenly and electrochemically into the slurry "glues" the fine solid particles to each other in floes that are large enough to be separated from the liquid by conventional separation methods.
  • a static mixer consists of a flow-through pipe with a series of helical baffles fixed to its inner walls.
  • a blade mixer comprises a rotating blade rotor in the vicinity of the base of the mixing tank. The powerful shear mixing in a blade mixer brings about a large vortex, but the speed difference at the tip of the blade is great and causes turbulence that is too strong and has a large energy intensity. It breaks the floes that have formed.
  • a drum mixer is a rotating drum, in which mixing blades have been attached to the inner surface of the wall. As the drum rotates, the blades mix the mass by lifting and dropping it on each cycle.
  • the purpose of the invention is to eliminate the aforementioned drawbacks.
  • the purpose of the invention is to present a method and equipment whereby a very gentle mixing is achieved that does not break up floes.
  • a further purpose of the invention is to present a method and equipment through which the amount of flocculant required can be reduced and cost savings achieved .
  • Yet another purpose of the invention is to present a method and equipment through which the size of the equipment demanded by the separation stage subsequent to the post-flocculation stage can be reduced and separation accelerated.
  • a flocculant is mixed gently into the slurry with a helical rotor mixer at a low mixing intensity, imparting to the mixture in the cylindrical mixer tank a vertical circulation flow, while simultaneously forming smaller turbulent flows in it essentially without directing shear forces on the mixture in order to avoid breaking up the floes.
  • the mixer belonging to the equipment accordant with the invention is a helical rotor mixer, which is adapted for gently mixing flocculant into slurry at a low mixing intensity and without directing shear forces on the mixture in order to avoid breaking up the floes.
  • the method and equipment accordant with the invention are especially useful in separating solids from slurry in the oil sand refining process, in which the slurry to be treated is the fine tailings generated in the oil sand refining process, in which the fine solid particles are mostly sand and clay, and the liquid is water, in which there are small amounts of residual bitumen .
  • the invention is not restricted solely to the oil sand application but is useful in the separation of solids and liquid in any slurry, where a flocculant is mixed into the slurry prior to separation.
  • the benefit of the invention is that a very gentle and homogenous mixing of flocculant into slurry is obtained with a helical rotor mixer at a low and uniform intensity so that the mixture is subjected to as little floc-breaking shear force as possible and the powerful turbulences it causes.
  • a helical rotor mixer provides a large surface area capable of moving slurry, whereby the energy is distributed evenly into the mixture. Helical rotor mixers have no tips that cause powerful turbulences and the breaking up of floes.
  • a helical rotor mixer enables coverage of the entire volume of the slurry, ensuring that it rotates the slurry around thoroughly in every part of the tank.
  • a smaller amount of flocculant is required than when mixing with conventional mixers, so that large cost savings can be made.
  • the size of the post-mixer separation equipment can be reduced, which also results in substantial cost savings.
  • a vertical circulation flow and turbulent flows are formed with a helical rotor mixer, and in its tank there is at least one helical rotor (known as a helix rotor) equipped with a spiral member rotating at a constant radius around a vertical rotation shaft.
  • a helical rotor known as a helix rotor
  • the flocculant is mixed into the slurry with a helical rotor mixer in which there are several helix rotors.
  • the peripheral speed of the rotor may become too great and start to form floc-breaking turbulence. Additionally, strength issues will arise. It is beneficial to increase the number of helix rotors so that the peripheral speeds can be kept low.
  • the flocculant is mixed into the slurry with a mixing intensity of the magnitude of 0.04 - 0.3 k /m 3 , preferably a maximum of 0.10 kW/m 3 .
  • polymers of long- chain anions or cations are used as the flocculant, such as polyacrylamide ( ⁇ 7 ⁇ ) and/or polyethylene oxide (PEO) .
  • the discrete separation stage subsequent to the flocculation stage, in which the solids and liquid of the flocculated slurry are separated from each other is accomplished using a mixer/settler, centrifuge or by vacuum filtration .
  • the flocculant is mixed into the slurry in a volumetric flow ratio of the order of magnitude of 1:40.
  • the helical rotor mixer consists of a tank, whose interior is bounded laterally by the cylindrical sidewall and below by the base; at least one helix rotor, which is arranged in the interior; a power device to rotate the helix rotor, and a group of elongated vertical baffles projecting from the sidewall towards the central axis of the tank.
  • the helix rotor consists of a vertical rotation shaft, which is connected to a power device, and the helix member, which is fixed to the rotation shaft with a support arms that are a radius away from the shaft.
  • the helix member is circular in cross-section, like a tube.
  • the helix member is non-circular in cross-section, like a flat rectangle .
  • the helical rotor mixer comprises several helix rotors.
  • the helical rotor mixer comprises 2 - 8 helix rotors.
  • the rotating shafts of the helix rotors are arranged radially with regard to the vertical centre axis of the tank and at a constant distance from one another.
  • Figure 1 presents the part of the process to which the invention relates in diagrammatic form, namely the mixer and separation equipment.
  • Figure 2 presents a vertical section of a helical rotor mixer of one embodiment accordant with the invention
  • Figure 3 presents section III-III from Figure 2
  • Figures 4 - 6 present sections of three other helical rotor mixer embodiments corresponding to Figure 3.
  • Figure 1 is a process diagram of the part of the process which comprises the mixer 1 and its subsequent separation equipment 2.
  • Slurry containing a suspension of liquid and fine solid particles is conducted to the mixer 1.
  • a quantity of liquid flocculant is added to the slurry that is materially less than the quantity of the slurry.
  • the slurry and flocculant are mixed with the mixer 1 to bring about contact between the fine solid particles and the flocculant in order to ' bind the fine solid particles to one another as floes.
  • the flocculated slurry is routed from the mixer to the separation equipment 2, in which the solids and liquid from the flocculated slurry are separated from each other .
  • the flocculant is mixed into the slurry for instance with a helical rotor mixer 1 accordant with Figure 2 with a low mixing intensity, for example a mixing intensity of the order of magnitude of 0.04 - 0.3 k /m 3 , preferably a maximum of 0.10 k /m 3 , gently providing a vertical macrocirculation flow in the mixture in the cylindrical mixer tank and simultaneously forming smaller turbulent microflows there without materially directing shear forces on the mixture, in order to avoid the floes from being broken up.
  • the vertical macrocirculation flow and the turbulent microflows are formed with the helical rotor mixer 1.
  • Figures 2 and 3 show a configuration in which the helical rotor mixer 1 comprises three double helix rotors 7.
  • the helical rotor mixer 1 consists of a tank 3, whose interior 4 is bounded laterally by a cylindrical inner wall 5 and beneath by the base 6.
  • the double helix rotors 7 are arranged in the interior 4 in a triangular formation a radius away from the central axis of the tank, as shown in Figure 3.
  • Each double helix rotor 7 is rotated by a power device 8.
  • Some baffles 9 protrude from the inner wall 5 of the tank 3 towards the central tank axis.
  • Each double helix rotor 7 comprises a vertical rotating shaft 10, to which a power device 8 is connected, and two identical helical tubes 11, which are circular in cross-section and are attached to the rotation shaft 10 by support arms 12 symmetrically opposite each other at a distance of one radius from the shaft.
  • Figures 4 - 6 depict further potential mixers in which the number of double helix rotors 7 is different.
  • the mixer 1 of Figure 4 there is only one double rotor 7 situated centrally in the tank.
  • the mixer 1 of Figure 5 there are five double helix rotors 7 arranged in a pentagonal configuration symmetrically with regard to the vertical central tank shaft.
  • the mixer 1 of Figure 6 there are eight double helix rotors 7 arranged in an octagonal configuration symmetrically with regard to the vertical central tank shaft.
  • Double helix rotors with two helical members are referred to in the examples above only by way of illustration. There may even be only one helical member in the helix rotor depending on the requirements of the application. Two helical members in one rotor make the rotor more robust structurally and obtain a more even distribution of mixing power compared with a single helical member.
  • the helical member its cross-section may be a shape other than circular. It may be a flat bar bent into a spiral, in which case the cross-section is a flat rectangle .

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Water Supply & Treatment (AREA)
  • Hydrology & Water Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Dispersion Chemistry (AREA)
  • Mixers Of The Rotary Stirring Type (AREA)
  • Extraction Or Liquid Replacement (AREA)
  • Separation Of Suspended Particles By Flocculating Agents (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

A method and equipment for separating solids from slurry containing a suspension of liquid and fine solid particles. An amount of liquid flocculant is added to the slurry that is considerably smaller than the amount of slurry. The slurry and flocculant are mixed with a mixer (1) to bring about contact between the fine solid particles and the flocculant in order to bind the fine solid particles to each other as floes. The solids and liquid of the flocculated slurry are separated from each other with a separation device (2) in a separate process stage after the flocculation stage. The flocculant is gently mixed into the slurry with a helical rotor mixer (1) at a low mixing intensity, giving the mixture in the cylindrical tank of the mixer a vertical macrocirculation flow and simultaneously creating in it smaller turbulent microflows without essentially subjecting the mixture to shear forces in order to avoid breaking up the floes. The method and equipment are extremely practical in the treatment of the fine tailings generated in oil sands refining.

Description

METHOD AND EQUIPMENT FOR SEPARATING SOLIDS FROM SLURRY AND USE OF THE METHOD AND/OR EQUIPMENT
FIELD OF THE INVENTION The invention relates to the method specified in the preamble of claim 1 for separating solids from slurry. The invention further relates to the equipment specified in the preamble of claim 9. The invention further relates to the use of the method and/or equipment as specified in claim 17.
BACKGROUND OF THE INVENTION
Oil sand is the term used for bitumen that is bound to grains of sand. Worldwide, the amount of oil in oil sands is of the same magnitude as the amount of normal petroleum. The exploitation of oil sands on a wide scale only began in the last couple of decades of the twentieth century, because it is more difficult to utilise than conventional oil.
Bitumen is formed from petroleum so that the petroleum has lost its lighter hydrocarbons and the remaining heaviest part has been partially decomposed by bacteria. Thus bitumen is partially degraded petroleum. Oil sands contain 1 - 20% bitumen.
The grains of sand are surrounded by a layer of water, including different kinds of particulates such as clay and other minerals. The bitumen film that surrounds the layer of water has to be separated from the sand, water and particulates before it can be processed further . The recovery and processing of oil sands into crude oil requires more energy and money than drilling the equivalent amount of oil from conventional deposits. For this reason, the wide-scale exploitation of oil sands has not previously been profitable, but with the rise in oil price and development in technology the operation has become economically viable. It is possible that in the future, when the current sources of oil are exhausted, people will turn to the use of oil sands as the major source of crude oil. The environmental impacts of refining oil sands are greater than those in conventional oil production.
This proposal focuses on the end of the oil sands refining process, and relates to the issue of what is known as post-treatment of fine tailings, which contain a suspension of water, sand, clay and bitumen whereby the solid particles are made to separate as effectively as possible from the water. Fine tailings are generated in the refining process in large quantities. Traditionally, in the Canadian oil sands area for example, tailings are routed to large artificial ponds for settling. However, clarification in these ponds is very slow and may take years. Currently, there has been an attempt to accelerate the separation of solids and water by flocculating the tailings and separating the solids and liquid with separation equipment, such as thickeners, centrifuges and filters. The solids can be used for instance for earthworks and landscaping and the separated water can be recycled back to the process to save raw water resources .
Some slurry processing methods and equipment for separating solids from slurry containing a suspension of liquid and fine solid particles are known in the prior art in connection with oil sand refining, for example in US patents 4,225,433 and 5,645,714. A quantity of liquid flocculant is added to the slurry that is substantially smaller than the amount of slurry. The slurry and flocculant are mixed to form a contact between the fine solid particles and the flocculant in order to bind the fine solid particles to each other as floes. Then the solids and liquid from the flocculated slurry are separated from one another in a separate process stage following the flocculation stage. The flocculant or flocculation agent is usually a long-chain polymer, which when mixed evenly and electrochemically into the slurry "glues" the fine solid particles to each other in floes that are large enough to be separated from the liquid by conventional separation methods.
In the known processes a static mixer, several blade mixers in series, or a drum mixer have been used for mixing the flocculant into the slurry. A static mixer consists of a flow-through pipe with a series of helical baffles fixed to its inner walls. A blade mixer comprises a rotating blade rotor in the vicinity of the base of the mixing tank. The powerful shear mixing in a blade mixer brings about a large vortex, but the speed difference at the tip of the blade is great and causes turbulence that is too strong and has a large energy intensity. It breaks the floes that have formed. A drum mixer is a rotating drum, in which mixing blades have been attached to the inner surface of the wall. As the drum rotates, the blades mix the mass by lifting and dropping it on each cycle. The problem with all of these mixers is that adverse, severe shear force is directed on the slurry during mixing. This breaks up the floes that have already been generated into smaller pieces, weakening the effectiveness of the post-mixing separation stage and undesirably leaving fine solid particles in the liquid. Attempts are being made to improve the situation by increasing the amount of flocculant, so that a great deal of flocculant is consumed, which is detrimental because flocculation agents are very expensive. A further problem is the fact that a separation facility greater in size is required in the separation stage than in the case where the floes are not broken during mixing. Moreover, the volume flow of the solids-containing slurry to be treated is large in comparison with that of the flocculant to be mixed into it, so that it is difficult to achieve uniform mixing using conventional mixing methods.
PURPOSE OF THE INVENTION
The purpose of the invention is to eliminate the aforementioned drawbacks.
In particular, the purpose of the invention is to present a method and equipment whereby a very gentle mixing is achieved that does not break up floes. A further purpose of the invention is to present a method and equipment through which the amount of flocculant required can be reduced and cost savings achieved . Yet another purpose of the invention is to present a method and equipment through which the size of the equipment demanded by the separation stage subsequent to the post-flocculation stage can be reduced and separation accelerated.
SUMMARY OF THE INVENTION
The features of the method accordant with the invention are characterized by what is disclosed in claim 1. Furthermore, the features of the equipment accordant with the invention are characterized by what is disclosed in claim 9. Further, the features of the use of the method and equipment accordant with the invention are characterized by what is disclosed in claim 17.
In the method accordant with the invention, a flocculant is mixed gently into the slurry with a helical rotor mixer at a low mixing intensity, imparting to the mixture in the cylindrical mixer tank a vertical circulation flow, while simultaneously forming smaller turbulent flows in it essentially without directing shear forces on the mixture in order to avoid breaking up the floes.
Correspondingly, the mixer belonging to the equipment accordant with the invention is a helical rotor mixer, which is adapted for gently mixing flocculant into slurry at a low mixing intensity and without directing shear forces on the mixture in order to avoid breaking up the floes. The method and equipment accordant with the invention are especially useful in separating solids from slurry in the oil sand refining process, in which the slurry to be treated is the fine tailings generated in the oil sand refining process, in which the fine solid particles are mostly sand and clay, and the liquid is water, in which there are small amounts of residual bitumen .
However, the invention is not restricted solely to the oil sand application but is useful in the separation of solids and liquid in any slurry, where a flocculant is mixed into the slurry prior to separation.
The benefit of the invention is that a very gentle and homogenous mixing of flocculant into slurry is obtained with a helical rotor mixer at a low and uniform intensity so that the mixture is subjected to as little floc-breaking shear force as possible and the powerful turbulences it causes. A helical rotor mixer provides a large surface area capable of moving slurry, whereby the energy is distributed evenly into the mixture. Helical rotor mixers have no tips that cause powerful turbulences and the breaking up of floes. A helical rotor mixer enables coverage of the entire volume of the slurry, ensuring that it rotates the slurry around thoroughly in every part of the tank. When using a helical rotor mixer a smaller amount of flocculant is required than when mixing with conventional mixers, so that large cost savings can be made. Furthermore, the size of the post-mixer separation equipment can be reduced, which also results in substantial cost savings.
In one embodiment of the method, a vertical circulation flow and turbulent flows are formed with a helical rotor mixer, and in its tank there is at least one helical rotor (known as a helix rotor) equipped with a spiral member rotating at a constant radius around a vertical rotation shaft.
In one embodiment of the method, the flocculant is mixed into the slurry with a helical rotor mixer in which there are several helix rotors. The bigger the slurry volume it is intended to mix and the bigger the mixing tank, the more advantageous it is to use several helix rotors in the same tank. In a small tank it is possible to use only one helix rotor, but if only one large helix rotor is used in a large tank, the peripheral speed of the rotor may become too great and start to form floc-breaking turbulence. Additionally, strength issues will arise. It is beneficial to increase the number of helix rotors so that the peripheral speeds can be kept low. In one embodiment of the method, the flocculant is mixed into the slurry with a mixing intensity of the magnitude of 0.04 - 0.3 k /m3, preferably a maximum of 0.10 kW/m3.
In one embodiment of the method, polymers of long- chain anions or cations are used as the flocculant, such as polyacrylamide (Ρ7ΛΜ) and/or polyethylene oxide (PEO) .
In one embodiment of the method, the discrete separation stage subsequent to the flocculation stage, in which the solids and liquid of the flocculated slurry are separated from each other, is accomplished using a mixer/settler, centrifuge or by vacuum filtration .
In one embodiment of the method, the flocculant is mixed into the slurry in a volumetric flow ratio of the order of magnitude of 1:40.
In one configuration of the equipment, the helical rotor mixer consists of a tank, whose interior is bounded laterally by the cylindrical sidewall and below by the base; at least one helix rotor, which is arranged in the interior; a power device to rotate the helix rotor, and a group of elongated vertical baffles projecting from the sidewall towards the central axis of the tank.
In one configuration of the equipment, the helix rotor consists of a vertical rotation shaft, which is connected to a power device, and the helix member, which is fixed to the rotation shaft with a support arms that are a radius away from the shaft. In one configuration of the equipment, the helix member is circular in cross-section, like a tube.
In one configuration of the equipment, the helix member is non-circular in cross-section, like a flat rectangle .
In one configuration of the equipment, the helical rotor mixer comprises several helix rotors.
In one configuration of the equipment, the helical rotor mixer comprises 2 - 8 helix rotors.
In one configuration of the equipment, the rotating shafts of the helix rotors are arranged radially with regard to the vertical centre axis of the tank and at a constant distance from one another.
LIST OF DRAWINGS
Below the invention is described in detail by means of example embodiments, with reference to the appended drawings, in which
Figure 1 presents the part of the process to which the invention relates in diagrammatic form, namely the mixer and separation equipment.
Figure 2 presents a vertical section of a helical rotor mixer of one embodiment accordant with the invention,
Figure 3 presents section III-III from Figure 2,
Figures 4 - 6 present sections of three other helical rotor mixer embodiments corresponding to Figure 3. DETAILED DESCRIPTION OF THE INVENTION
Figure 1 is a process diagram of the part of the process which comprises the mixer 1 and its subsequent separation equipment 2.
Slurry containing a suspension of liquid and fine solid particles is conducted to the mixer 1. A quantity of liquid flocculant is added to the slurry that is materially less than the quantity of the slurry. The slurry and flocculant are mixed with the mixer 1 to bring about contact between the fine solid particles and the flocculant in order to ' bind the fine solid particles to one another as floes. The flocculated slurry is routed from the mixer to the separation equipment 2, in which the solids and liquid from the flocculated slurry are separated from each other .
The flocculant is mixed into the slurry for instance with a helical rotor mixer 1 accordant with Figure 2 with a low mixing intensity, for example a mixing intensity of the order of magnitude of 0.04 - 0.3 k /m3, preferably a maximum of 0.10 k /m3, gently providing a vertical macrocirculation flow in the mixture in the cylindrical mixer tank and simultaneously forming smaller turbulent microflows there without materially directing shear forces on the mixture, in order to avoid the floes from being broken up. The vertical macrocirculation flow and the turbulent microflows are formed with the helical rotor mixer 1.
As an example, Figures 2 and 3 show a configuration in which the helical rotor mixer 1 comprises three double helix rotors 7. The helical rotor mixer 1 consists of a tank 3, whose interior 4 is bounded laterally by a cylindrical inner wall 5 and beneath by the base 6. The double helix rotors 7 are arranged in the interior 4 in a triangular formation a radius away from the central axis of the tank, as shown in Figure 3. Each double helix rotor 7 is rotated by a power device 8. Some baffles 9 protrude from the inner wall 5 of the tank 3 towards the central tank axis. Each double helix rotor 7 comprises a vertical rotating shaft 10, to which a power device 8 is connected, and two identical helical tubes 11, which are circular in cross-section and are attached to the rotation shaft 10 by support arms 12 symmetrically opposite each other at a distance of one radius from the shaft.
Figures 4 - 6 depict further potential mixers in which the number of double helix rotors 7 is different. In the mixer 1 of Figure 4 there is only one double rotor 7 situated centrally in the tank. In the mixer 1 of Figure 5 there are five double helix rotors 7 arranged in a pentagonal configuration symmetrically with regard to the vertical central tank shaft. In the mixer 1 of Figure 6 there are eight double helix rotors 7 arranged in an octagonal configuration symmetrically with regard to the vertical central tank shaft. There may be any suitable number of double helix rotors 7 whatsoever.
Double helix rotors with two helical members are referred to in the examples above only by way of illustration. There may even be only one helical member in the helix rotor depending on the requirements of the application. Two helical members in one rotor make the rotor more robust structurally and obtain a more even distribution of mixing power compared with a single helical member. As for the helical member, its cross-section may be a shape other than circular. It may be a flat bar bent into a spiral, in which case the cross-section is a flat rectangle .
The invention is not restricted to refer only to the example embodiments presented above, but many variants are possible while remaining within the framework of the concept of the invention as specified in the patent claims.

Claims

PATENT CLAIMS
1. A method for separating solids from slurry that contains a suspension of liquid and fine solid particles, and in which method
an amount of liquid flocculant is added to the slurry that is materially smaller than the amount of slurry,
- the slurry and flocculant are mixed to bring about contact between the fine solid particles and the flocculant in order to bind the fine solid particles to each other as floes, and
- the solids and liquid of the flocculated slurry are separated from each other in a separate process stage after the flocculation stage,
characterised in that the flocculant is gently mixed into the slurry with a helical rotor mixer at low mixing intensity, giving the mixture in the cylindrical tank of the mixer a vertical macrocirculation flow and simultaneously creating in it smaller turbulent microflows without essentially subjecting the mixture to shear forces in order to avoid breaking up the floes.
2. A method according to claim 1, characterised in that a vertical circulation flow and turbulent flows are formed with a helical rotor mixer, in the tank of which there is at least one helix rotor equipped with a helical member rotating at a constant radius from the vertical rotation shaft.
3. A method according to claims 1 or 2, characterised in that the flocculant is mixed into the slurry with a helical rotor mixer, which has several helix rotors.
4. A method according to any of the preceding claims 1
- 3, characterised in that: the flocculant is mixed into the slurry at a mixing intensity, which is of the magnitude of 0.04 - 0.3 k /m3, preferably a maximum of 0.10 kW/m3.
5. A method according to any of the preceding claims 1
- 4, characterised in that the flocculant used is a long-chain anionic or cationic polymer, such as polyacrylamide (PAM) and/or polyethylene oxide (PEO) .
6. A method according to any of the preceding claims 1
- 5, characterised in that a discrete separation stage after the flocculation stage, in which the solids and liquid of the flocculated slurry are separated from each other, is achieved with a thickener/clarifier, by centrifuge or by vacuum filtration.
7. A method according to any of the preceding claims 1
- 6, characterised in that the flocculant is mixed into the slurry at a volumetric flow ratio that is of the magnitude of 1:40.
8. A method according to any of the preceding claims 1
- 7, characterised in that the slurry is the fine tailings containing fine solids generated in the oil sands refining process, in which the fine solid particles are largely sand and clay, and the liquid is water in which there are small amounts of residual bitumen .
9. Equipment for separating solids from slurry that contains liquid and fine solid particles, which are in colloidal solution in the liquid, and where the equipment comprises
- a mixer (1) for mixing the flocculant to bring about contact between the fine solid particles and the flocculant in order to bind the fine solid particles to each other as floes, and - a separation device (2), which is arranged after the mixer in order to separate the solids and liquid, characterised in that the mixer (1) is a helical rotor mixer, which is adapted for gently mixing flocculant into slurry at a low mixing intensity and essentially without directing shear forces in order to avoid breaking up the floes.
10. Equipment according to claim 9, characterised in that the helical rotor mixer (1) consists of
- a tank (3), the interior (4) of which is bounded laterally by the cylindrical-shaped sidewall (5) and beneath by the base (6),
at least one helix rotor (7), which is arranged in the interior (4),
- a power device (8) to rotate the helix rotor ( 7 ) , and
- a group of elongated vertical flow baffles (9), protruding from the sidewall towards the central axis of the tank.
11. Equipment according to claim 10, characterised in that the helix rotor (7) consists of
- a vertical rotation shaft (10), which is connected to a power device (8), and
- one or two helix members (11), which are fixed to the rotation shaft (10) by support arms (12) at a distance of one radius from the rotation shaft.
12. Equipment according to claim 11, characterised in that the helix member (11) is circular in cross- section .
13. Equipment according to claim 11, characterised in that the helix member (11) is non-circular in cross- section, such as a flat rectangle.
14. Equipment according to any of the preceding claims 9 - 13, characterised in that the helical rotor mixer (1) comprises several helix rotors (7).
15. Equipment according to claim 14, characterised in that the helical rotor mixer (1) comprises 2 - 8 helix rotors ( 7 ) .
16. Equipment according to claim 15, characterised in that the rotation shafts (10) of the helix rotors (7) are arranged radially with regard to the vertical central axis of the tank (3) .
17. The use of a method according to any of the preceding claims 1 - 8 and/or equipment according to any of the preceding claims 9 - 16 in the oil sands refining process.
PCT/FI2010/000073 2009-12-08 2010-12-08 Method and equipment for separating solids from slurry and use of the method and/or equipment Ceased WO2011070218A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FI20096296 2009-12-08
FI20096296A FI123597B (en) 2009-12-08 2009-12-08 Method and apparatus for separating solid particles from sludge and using the method and / or apparatus

Publications (1)

Publication Number Publication Date
WO2011070218A1 true WO2011070218A1 (en) 2011-06-16

Family

ID=41462762

Family Applications (2)

Application Number Title Priority Date Filing Date
PCT/FI2010/000073 Ceased WO2011070218A1 (en) 2009-12-08 2010-12-08 Method and equipment for separating solids from slurry and use of the method and/or equipment
PCT/FI2010/000074 Ceased WO2011070219A1 (en) 2009-12-08 2010-12-08 Method and apparatus to create uniform mixing in connection with a hydrometalurgical process

Family Applications After (1)

Application Number Title Priority Date Filing Date
PCT/FI2010/000074 Ceased WO2011070219A1 (en) 2009-12-08 2010-12-08 Method and apparatus to create uniform mixing in connection with a hydrometalurgical process

Country Status (11)

Country Link
EP (1) EP2509709A4 (en)
CN (1) CN102665887B (en)
AU (1) AU2010329807A1 (en)
BR (1) BR112012013894A2 (en)
CA (1) CA2780852A1 (en)
CL (1) CL2012001477A1 (en)
EA (1) EA022724B1 (en)
FI (2) FI123597B (en)
PE (1) PE20130300A1 (en)
WO (2) WO2011070218A1 (en)
ZA (1) ZA201203911B (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015168378A1 (en) 2014-04-30 2015-11-05 Dow Global Technologies Llc Polymeric flocculants for treating aqueous mineral suspensions
WO2015168376A1 (en) 2014-04-30 2015-11-05 Dow Global Technologies Llc Treatment of aqueous mineral suspensions with a polymeric flocculants
WO2016019213A1 (en) 2014-07-31 2016-02-04 Dow Global Technologies Llc In-line dynamic mixing apparatus for flocculating and dewatering oil sands fine tailings
EP2864446A4 (en) * 2012-06-21 2016-03-02 Suncor Energy Inc IMPROVED TECHNIQUES FOR DEHYDRATION OF FINE AND THICK RESIDUES
WO2017034790A1 (en) 2015-08-25 2017-03-02 Dow Global Technologies Llc Flocculation of high-solids mineral slurries
CN106861501A (en) * 2017-03-20 2017-06-20 无锡科技职业学院 A kind of high-shear emulsifying dissolves mixing kettle
WO2017205249A1 (en) 2016-05-27 2017-11-30 Dow Global Technologies Llc Method of treating high-solids mineral slurries with polymeric flocculants
WO2018022352A1 (en) 2016-07-25 2018-02-01 Dow Global Technologies Llc Acoustic mixing for flocculant addition to mineral suspensions
WO2018057325A1 (en) 2016-09-23 2018-03-29 Dow Global Technologies Llc Process for tailings remediation
WO2018063810A1 (en) 2016-09-27 2018-04-05 Dow Global Technologies Llc Process for dewatering an aqueous process stream
CN112456672A (en) * 2019-09-09 2021-03-09 国家能源投资集团有限责任公司 Mine water treatment method and system
EP3680007A4 (en) * 2018-03-05 2021-07-07 Nippon Sosey Kogyo Co., Ltd. ROTARY MIXER OF A TWO-LIQUID MIXING INJECTION MACHINE
US20230201778A1 (en) * 2020-04-20 2023-06-29 Metso Outotec Finland Oy Mixing arrangement, mixer settler unit and use
CN119080378A (en) * 2024-11-05 2024-12-06 胜利油田万和石油工程技术有限责任公司 Oil drilling mud processing system

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103936042A (en) * 2013-01-22 2014-07-23 贵阳铝镁设计研究院有限公司 Three-shaft stirring decomposing tank
CA2823459C (en) 2013-08-09 2015-06-23 Imperial Oil Resources Limited Method of using a silicate-containing stream from a hydrocarbon operation or from a geothermal source to treat fluid tailings by chemically-induced micro-agglomeration
CN104226147B (en) * 2014-10-15 2016-08-17 浙江辰鸿纺织品科技有限公司 A kind of for window cloth slurry high efficiency dispersion mixing arrangement
CN109529703A (en) * 2018-11-28 2019-03-29 河南易成新能源股份有限公司 Graphite product ingredient mixing arrangement

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040168987A1 (en) * 2001-06-25 2004-09-02 Bror Nyman Method and apparatus for clarifying a slurry
CA2673982A1 (en) * 2008-07-28 2010-01-28 Hunton Energy Holdings, LLC Basic filtration of bitumen fines

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR615110A (en) * 1926-04-26 1926-12-30 Mixer
NL52125C (en) * 1939-03-31 1942-03-16
DE1225951B (en) * 1961-08-10 1966-09-29 Wilhelm Heinrich Schmidt Mixing device
US4198376A (en) * 1974-02-14 1980-04-15 Rhone-Progil Vertical autoclave for bulk polymerization of vinyl chloride based polymers and copolymers
US5248485A (en) * 1990-04-04 1993-09-28 Outokumpu Oy Method for mixing liquid, solids and gas and for simultaneously separating gas or gas and solids from the liquid
CN2158301Y (en) * 1993-03-26 1994-03-09 郭洪臣 Double-shaft helice mixer
DE19901267B4 (en) * 1999-01-15 2006-08-10 Löhr, Anke, Dr. Mixing and treatment device
FI123662B (en) * 2006-02-17 2013-08-30 Outotec Oyj Process and mixing plant for mixing gas in sludge in a closed reactor

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040168987A1 (en) * 2001-06-25 2004-09-02 Bror Nyman Method and apparatus for clarifying a slurry
CA2673982A1 (en) * 2008-07-28 2010-01-28 Hunton Energy Holdings, LLC Basic filtration of bitumen fines

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2864446A4 (en) * 2012-06-21 2016-03-02 Suncor Energy Inc IMPROVED TECHNIQUES FOR DEHYDRATION OF FINE AND THICK RESIDUES
WO2015168376A1 (en) 2014-04-30 2015-11-05 Dow Global Technologies Llc Treatment of aqueous mineral suspensions with a polymeric flocculants
WO2015168378A1 (en) 2014-04-30 2015-11-05 Dow Global Technologies Llc Polymeric flocculants for treating aqueous mineral suspensions
US11001512B2 (en) 2014-04-30 2021-05-11 Dow Global Technologies Llc Treatment of aqueous mineral suspensions with polymeric flocculants
US10315944B2 (en) 2014-04-30 2019-06-11 Dow Global Technologies Llc Polymeric flocculants for treating aqueous mineral suspensions
WO2016019213A1 (en) 2014-07-31 2016-02-04 Dow Global Technologies Llc In-line dynamic mixing apparatus for flocculating and dewatering oil sands fine tailings
US10781117B2 (en) 2015-08-25 2020-09-22 Dow Global Technologies Llc Flocculation of high-solids mineral slurries
WO2017034790A1 (en) 2015-08-25 2017-03-02 Dow Global Technologies Llc Flocculation of high-solids mineral slurries
US11001514B2 (en) 2016-05-27 2021-05-11 Dow Global Technologies Llc Method of treating high-solids mineral slurries with polymeric flocculants
WO2017205249A1 (en) 2016-05-27 2017-11-30 Dow Global Technologies Llc Method of treating high-solids mineral slurries with polymeric flocculants
WO2018022352A1 (en) 2016-07-25 2018-02-01 Dow Global Technologies Llc Acoustic mixing for flocculant addition to mineral suspensions
WO2018057325A1 (en) 2016-09-23 2018-03-29 Dow Global Technologies Llc Process for tailings remediation
WO2018063810A1 (en) 2016-09-27 2018-04-05 Dow Global Technologies Llc Process for dewatering an aqueous process stream
CN106861501A (en) * 2017-03-20 2017-06-20 无锡科技职业学院 A kind of high-shear emulsifying dissolves mixing kettle
EP3680007A4 (en) * 2018-03-05 2021-07-07 Nippon Sosey Kogyo Co., Ltd. ROTARY MIXER OF A TWO-LIQUID MIXING INJECTION MACHINE
CN112456672A (en) * 2019-09-09 2021-03-09 国家能源投资集团有限责任公司 Mine water treatment method and system
US20230201778A1 (en) * 2020-04-20 2023-06-29 Metso Outotec Finland Oy Mixing arrangement, mixer settler unit and use
EP4139031A4 (en) * 2020-04-20 2024-01-24 Metso Finland Oy Mixing arrangement, mixer settler unit and use
CN119080378A (en) * 2024-11-05 2024-12-06 胜利油田万和石油工程技术有限责任公司 Oil drilling mud processing system

Also Published As

Publication number Publication date
EP2509709A4 (en) 2016-01-06
EA201290405A1 (en) 2013-01-30
PE20130300A1 (en) 2013-03-22
AU2010329807A1 (en) 2012-06-21
ZA201203911B (en) 2013-04-24
CL2012001477A1 (en) 2012-11-16
EP2509709A1 (en) 2012-10-17
FI124092B (en) 2014-03-14
CA2780852A1 (en) 2011-06-16
WO2011070219A8 (en) 2011-11-17
FI20096296A0 (en) 2009-12-08
EA022724B1 (en) 2016-02-29
BR112012013894A2 (en) 2016-05-03
WO2011070219A1 (en) 2011-06-16
FI20100318L (en) 2011-06-09
CN102665887A (en) 2012-09-12
FI20096296L (en) 2011-06-09
CN102665887B (en) 2015-06-24
FI20100318A0 (en) 2010-09-16
FI123597B (en) 2013-07-31
AU2010329807A8 (en) 2012-07-19

Similar Documents

Publication Publication Date Title
WO2011070218A1 (en) Method and equipment for separating solids from slurry and use of the method and/or equipment
DK1697053T3 (en) Process and reactor for flocculation treatment
KR101673668B1 (en) A Circular sludge collector
CN113843051B (en) Multi-stage stirring circulation slurry mixing equipment and method
JP2002058908A (en) Flocculating sedimentation treatment equipment
CN104692605A (en) Reduction treatment method and device for oily sludge
GB2488995A (en) Solid and liquid separation
EP3221269A1 (en) Improved ballasted clarification system
CN101219850A (en) Technique for processing blue algae slurry with intracapsular dehydration technique
US12053749B2 (en) Mixing apparatus and method of operation
CN113413646B (en) Supergravity device for solid-liquid separation
JP2011005375A (en) Solid-liquid separator
CN117771752A (en) Mechanical accelerating clarifier dosing equipment and dosing process
JP2002058912A (en) Whirling flow type flocculating/separation equipment
US20200131059A1 (en) Water treatment plant having integrated ballasted flocculation and decantation, and a corresponding method
CN112028305A (en) Recycling method, separating equipment and recycling system of concrete washing water
CN111807677A (en) Zero-emission purification high-viscosity polymer-containing oil sludge treatment method and treatment system
CN104743731A (en) Method for removing heavy oil by dense medium surface modifying process
CN110743698B (en) A kind of device and method for separating and collecting sand and scum in sediments
CN210419615U (en) Magnetic powder sludge separation structure and sewage settling system
CN1291792C (en) Mixture air floatation type dynamic vortex flow separation method and its device
CN223392954U (en) Multi-element gold concentrate pulp-liquid separation thickener
CN111606528A (en) Oily sludge cleaning tank and efficient stirring device thereof
CN112295745A (en) Horizontal screw machine feed arrangement structure
US2295714A (en) Water treating apparatus

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 10835536

Country of ref document: EP

Kind code of ref document: A1

DPE1 Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101)
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 10835536

Country of ref document: EP

Kind code of ref document: A1