Bioslurry reactor for treatment of slurries containing minerals, soils and sludges

• US 5,227,136 A
• Filed: 11/05/1990
• Issued: 07/13/1993
• Est. Priority Date: 02/07/1986
• Status: Expired due to Fees

• Current Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Original Assignee: Envirotech Corporation
• Inventors: O'Connor, Lawrence T., Duncan, Steven P., Emmett, Robert C. Jr., Brox, Gunter H., Hanify, Douglas E.
• Primary Examiner(s): Housel, James C.
• Assistant Examiner(s): Le, Long V.
• Application Number:
  US07/612,585
• Time in Patent Office: 981 Days
• Field of Search: 435/813, 435/311, 435/314, 435/315, 210/197, 210/202, 210/208, 210/221.2, 422/135, 422/225, 422/227, 423/DIG. 17, 423/20
• US Class Current: 422/225
• CPC Class Codes: B01F 23/23124 consisting of flexible porous or perforated material, e.g. fabric
• CPC Class Codes: B01F 23/231242 in the form of slits or cut-out openings
• CPC Class Codes: B01F 23/231264 being in the form of plates, flat beams, flat membranes or films
• CPC Class Codes: B01F 23/2331 characterised by the introduction of the gas along the axis of the stirrer or along the stirrer elements
• CPC Class Codes: B01F 23/2368 Mixing receptacles, e.g. tanks, vessels or reactors, being completely closed, e.g. hermetically closed
• CPC Class Codes: B01F 23/237612 Oxygen
• CPC Class Codes: B01F 25/212 the injectors being movable, e.g. rotating
• CPC Class Codes: B01F 27/1121 pin-shaped
• CPC Class Codes: B01F 27/1124 rake-shaped or grid-shaped
• CPC Class Codes: B01F 27/1125 with vanes or blades extending parallel or oblique to the stirrer axis
• CPC Class Codes: B01F 33/82 Combinations of dissimilar mixers
• CPC Class Codes: B01J 8/10 moved by stirrers or by rotary drums or rotary receptacles or endless belts
• CPC Class Codes: B09C 1/08 chemically
• CPC Class Codes: B09C 1/10 microbiologically, biologically or by using enzymes
• CPC Class Codes: C02F 11/004 Sludge detoxification
• CPC Class Codes: C02F 3/085 Fluidized beds
• CPC Class Codes: C02F 3/10 Packings; Fillings; Grids packing elements in general B01J19/30, B01J19/32
• CPC Class Codes: C02F 3/121 Multistep treatment
• CPC Class Codes: C02F 3/1221 comprising treatment of the recirculated sludge
• CPC Class Codes: C02F 3/201 Perforated, resilient plastic diffusers, e.g. membranes, sheets, foils, tubes, hoses
• CPC Class Codes: C02F 3/207 : with axial thrust propellers
• CPC Class Codes: C02F 3/223 : using "air-lift"
• CPC Class Codes: C02F 9/20 : Portable or detachable small-scale multistage treatment devices, e.g. point of use or laboratory water purification systems
• CPC Class Codes: C22B 3/02 : Apparatus therefor
• CPC Class Codes: C22B 3/18 : with the aid of microorganisms or enzymes, e.g. bacteria or algae
• CPC Class Codes: Y02P 10/20 : Recycling
• CPC Class Codes: Y02W 10/10 : Biological treatment of water, waste water, or sewage
• CPC Class Codes: Y10S 423/17 : Microbiological reactions

Abstract

A reactor vessel for use in treating slurries containing minerals, soils or sludges contaminated with toxic organic substances is disclosed. The vessel includes a tank, having a sealed cover, a mixer arrangement, an air supply arrangement and an exhaust gas recycling system. The air supply arrangement includes one or more porous, flexible membrane diffusers adapted for introducing gas, in the form of fine bubbles, into a tank-contained slurry.

Claims

1. Apparatus for use in treating, through use of bacteria, minerals, soils or sludges which have been contaminated with hazardous waste organic compounds, said apparatus comprising:

slurry-forming means for adding water to said minerals, soils or sludges to form a slurry;

screening means, associated with said slurry-forming means, for removing all solid material of a preselected size from said slurry;

a container means associated with said screening means for containing a quantity of slurry and bacteria suited to treat hazardous waste organic compounds;

an oxygen supply means mounted within said container means, said oxygen supply means including at least one flexible porous membrane diffuser adapted for receiving a supply of oxygen-containing gas and distributing said gas into said container means in a form of fine bubbles;

a mixing means mounted within said container means for mixing and recirculating the slurry contained within said container means;

an exhaust gas recycling means mounted on said container means for drawing off a quantity of exhaust gases from said container means, treating said exhaust gas by extracting carbon dioxide therefrom, injecting oxygen into said quantity of exhaust gas and thereafter reintroducing said treated exhaust gas into said container means by means of said oxygen supply means, wherein said container means is sealed to prevent escape of exhaust gases; and

dewatering means, associated with said container means, for receiving said slurry from said container means and dewatering said slurry.

2. The apparatus of claim 1, wherein said slurry-forming means includes an attrition mill.

3. The apparatus of claim 1, wherein said screening means includes a trommel screen.

4. The apparatus of claim 1, wherein said dewatering means includes a pressure filter.

5. The apparatus of claim 1 wherein said dewatering means includes a vacuum filter.

6. The apparatus of claim 1, wherein said dewatering means includes a centrifuge.

7. The apparatus of claim 1 wherein said container means includes a plurality of tanks.

21. The apparatus of claim 1 wherein said mixing means comprises:

an outlet defined in a bottom of said container means;

a conduit, having a first end and a second end, said first end being mounted on said outlet, said conduit extending outwardly away from said container means, and then upwardly along an exterior surface of said container means along a height of said container means, said conduit extending into an interior of said container means at its second end;

an open-ended draft tube mounted vertically upright within said container means, said second end of said conduit being mounted to empty into said open-ended draft tube; and

a driven impeller mounted within said draft tube;

wherein said second end of said conduit is oriented to discharge slurry and solids contained therein into said draft tube at a location elevationally above said impeller.

8. Apparatus for use in treating, through use of bacteria, minerals, soils or sludges, which have been contaminated with hazardous waste organic compounds, said apparatus comprising:

slurry-forming means for adding water to said minerals, soils or sludges to form a slurry;

screening means, associated with said slurry-forming means for screening said slurry to remove therefrom all solid material over a preselected size, to constitute a quantity of sized, slurry-borne minerals, soils or sludges;

washing means associated with said screening means for washing said sized quantity of sized minerals, soils or sludges;

classifying means, associated with said washing means for classifying said quantity of sized minerals, soils or sludges, said classifying means being adapted for removing fine material of a preselected size and excess water from said slurry;

a container means, associated with said classifying means, for containing a quantity of slurry and bacteria suited to treat hazardous waste organic compounds;

an oxygen supply means, mounted within said container means, said oxygen supply means including at least one flexible porous membrane diffuser adapted for receiving a supply of oxygen-containing gas and distributing said gas into said container means in a form of fine bubbles;

a mixing means mounted within said container means for mixing and recirculating the slurry contained within said container means;

an exhaust gas recycling means mounted on said container means for drawing off a quantity of exhaust gases from said container means, treating said exhaust gas by extracting carbon dioxide therefrom, injecting oxygen into said quantity of exhaust gas and thereafter reintroducing said treated exhaust gas into said container means by means of said oxygen supply means, wherein said container means is sealed to prevent escape of exhaust gases; and

dewatering means, associated with said container means, for receiving said slurry from said container means and dewatering said slurry.

9. The apparatus of claim 8, wherein said slurry-forming means includes an attrition mill.

10. The apparatus of claim 8, wherein said screening means includes a trommel screen.

11. The apparatus of claim 8, wherein said dewatering means includes a pressure filter.

12. The apparatus of claim 8, wherein said dewatering means includes a vacuum filter.

13. The apparatus of claim 8, wherein said dewatering means includes a centrifuge.

14. The apparatus of claim 8, wherein said classifying means includes a countercurrent washing screw classifier.

15. A reactor vessel for use in treating, through use of bacteria, slurries containing minerals, soils, or sludges, including such slurries as may be contaminated with hazardous waste organic compounds, said slurries having a solids concentration by weight of at least approximately 6% or more, said vessel comprising:

a container means, said container means having a bottom, for containing a quantity of slurry;

an oxygen supply means mounted within said container means, said oxygen supply means including at least one flexible porous membrane diffuser adapted for receiving a supply of oxygen-containing gas and distributing said gas into said container means in a form of fine bubbles;

a means for mixing and recirculating the slurry contained within the tank;

a means for withdrawing solids that have settled onto said bottom of said container means;

a means for transporting said withdrawn solids upwards and reintroducing said solids into said container means at a location above said bottom; and

rake means mounted adjacent a bottom of said container means thereof, for scraping said bottom and directing any concentrations of solids deposited on said bottom to a collection location within said vessel proximate said means for withdrawing solids.

16. The reactor vessel of claim 15, wherein said container means is fitted with an airlift means for upwardly transporting said solids from said collection location and thereafter introducing said solids into said slurry above said container means bottom.

17. The reactor vessel of claim 15, wherein said container means includes a biomass-carrying medium screening means which includes a quantity of biocatalyst carrier particulates, adapted for bacteria and facilitating their attachment thereon, being placed in said slurry within said container means, and a screen mounted over a discharge port of said container means adapted for capturing said particulates from slurry discharged as effluent from said container means.

18. The reactor vessel of claim 16, wherein said airlift means is adapted for transporting said solids to a height above a surface level of the slurry contained within said container means and thereafter discharging said solids over said surface level.

19. The reactor vessel of claim 16, wherein said airlift means is adapted for discharging said solids over a screen mounted within said container means and over a discharge conduit adapted for directing slurry as effluent away from said container means.

20. The reactor vessel of claim 15 wherein said flexible porous membrane diffuser is generally upright.