System and method for biological wastewater treatment and for using the byproduct thereof

• US 7,736,508 B2
• Filed: 12/17/2007
• Issued: 06/15/2010
• Est. Priority Date: 09/18/2006
• Status: Active Grant

• Current Assignee: Christopher A. Limcaco
• Original Assignee: Christopher A. Limcaco
• Inventors: Limcaco, Christopher A.
• Primary Examiner(s): PRINCE JR, FREDDIE GARY
• Application Number:
  US11/957,648
• Publication Number:
  US 20080135475A1
• Time in Patent Office: 911 Days
• Field of Search: 210/601, 210/603, 210/621, 210/602
• US Class Current: 210/602
• CPC Class Codes: C02F 1/76 with halogens or compounds of halogens C02F1/4674 takes precedence
• CPC Class Codes: C02F 2303/24 Separation of coarse particles, e.g. by using sieves or screens
• CPC Class Codes: C02F 2305/06 Nutrients for stimulating the growth of microorganisms
• CPC Class Codes: C02F 3/082 Rotating biological contactors
• CPC Class Codes: C02F 3/32 characterised by the animals or plants used, e.g. algae
• CPC Class Codes: C05F 7/00 Fertilisers from waste water, sewage sludge, sea slime, ooze or similar masses
• CPC Class Codes: C12P 5/023 Methane
• CPC Class Codes: C12P 7/08 produced as by-product or from waste or cellulosic material substrate
• CPC Class Codes: Y02A 40/20 Fertilizers of biological origin, e.g. guano or fertilizers made from animal corpses
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel
• CPC Class Codes: Y02W 10/10 Biological treatment of water, waste water, or sewage
• CPC Class Codes: Y02W 10/37 using solar energy
• CPC Class Codes: Y02W 30/40 Bio-organic fraction processing; Production of fertilisers from the organic fraction of waste or refuse

Abstract

A wastewater treatment system and process biologically treats wastewater to produce substantially clean water effluent and byproducts. The treatment system includes an array of media wheels that rotate into and out of exposure to sunlight for sustained algae growth. One byproduct is algae removed from the rotating media wheels, which may be provided to other processing facilities to produce, for instance, bio-diesel fuel. Waste CO₂ from the processing facility may also be returned to the treatment system for enhanced algae growth. Bacteria is provided to form a symbiotic relationship with the algae, fueled by sunlight to effectively remove toxic materials from the wastewater. Large scale facilities may integrate the treatment systems in a regenerative cycle in which the biomass obtained from the algal colonies is used in a separate facility and byproducts of the operation of the separate facility are used by the treatment system to fuel further algal growth.

Claims

1. A process for wastewater treatment comprising:

operating a first treatment facility operable to biologically treat wastewater to produce a substantially clean effluent and a byproduct of biosolids;

using photosynthesis in the first treatment facility to increase the biosolids produced by the facility;

extracting the biosolids from the first treatment facility;

providing the biosolids to a separate facility for processing the biosolids; and

recycling less than the entire output from the separate facility back to the first treatment facility to affect its operation.

2. The wastewater treatment process of claim 1, wherein the separate facility is a power generation plant operable to generate electricity from the combustion of the biosolids.

3. The wastewater treatment process of claim 2, wherein the recycled output of the power generation plant is CO₂.

4. The wastewater treatment process of claim 3, wherein the CO₂ output from the power generation plant is substantially completely attributable to combustion of the biosolids.

5. The wastewater treatment process of claim 4, wherein the recycled output includes excess heat from the combustion of the biosolids.

6. The wastewater treatment process of claim 2, wherein the recycled output of the power generation plant is electricity that is supplied to the treatment facility to power electrical components thereof.

7. The wastewater treatment process of claim 1, further comprising:

operating one or more successive additional treatment facilities to receive effluent and recycled output from the separate facility when the capacity of the prior operated treatment facilities to use the recycled output is exceeded.

8. The wastewater treatment process of claim 7, wherein additional treatment facilities are added until a desired output of the separate facility is achieved.

9. The wastewater treatment process of claim 7, wherein the biosolids byproduct of each of the additional treatment facilities is combined and provided to the separate facility.

10. The wastewater treatment process of claim 1, wherein the step of providing the biosolids to a separate facility includes drying the biosolids extracted from the first treatment facility.

11. The wastewater treatment process of claim 10, wherein the recycled output includes excess heat from the combustion of the biosolids that is used to dry the biosolids.

12. The wastewater treatment process of claim 1, wherein the first treatment facility uses algae to increase the biosolids produced by the facility.

13. The wastewater treatment process of claim 1 further comprising removing biosolids from the wastewater prior to introduction to the first treatment facility and combining the removed biosolids with the biosolids extracted from the first treatment facility prior to being provided to the separate facility.

14. The wastewater treatment process of claim 1, wherein the separate treatment facility combusts the extracted biosolids.

15. The wastewater treatment process of claim 14, wherein at least a portion of the clean effluent is provided to the separate facility for conversion into steam.