Multi-functional fecal waste and garbage processor and associated methods

• US 10,247,049 B2
• Filed: 06/21/2017
• Issued: 04/02/2019
• Est. Priority Date: 11/14/2014
• Status: Active Grant

• Current Assignee: Bill & Melinda Gates Foundation
• Original Assignee: Bill & Melinda Gates Foundation
• Inventors: Janicki, Peter
• Primary Examiner(s): Nguyen, Hoang M
• Application Number:
  US15/629,642
• Publication Number:
  US 20170283275A1
• Time in Patent Office: 650 Days
• Field of Search: 60670, 34 72, 34 73, 34 86, 34210, 34407
• CPC Class Codes: B01D 1/04 Evaporators with horizontal tubes
• CPC Class Codes: B01D 1/226 in the form of a screw or with helical blade members
• CPC Class Codes: C02F 1/001 Processes for the treatment of water whereby the filtration technique is of importance C02F1/44 takes precedence; construction of filters in general B01D24/00 - B01D41/00
• CPC Class Codes: C02F 1/004 using large scale industrial sized filters
• CPC Class Codes: C02F 1/04 by distillation or evaporation
• CPC Class Codes: C02F 1/20 by degassing, i.e. liberation of dissolved gases degasification of liquids in general B01D19/00; arrangement of degassing apparatus in boiler feed supply F22D
• CPC Class Codes: C02F 1/283 using coal, charred products, or inorganic mixtures containing them
• CPC Class Codes: C02F 1/444 by ultrafiltration or microfiltration
• CPC Class Codes: C02F 11/06 by oxidation incinerators for burning waste liquors, e.g. sulfite liquor from paper-making plant F23G7/04
• CPC Class Codes: C02F 11/12 by de-watering, drying or thickening
• CPC Class Codes: C02F 11/13 by heating
• CPC Class Codes: C02F 2303/06 Sludge reduction, e.g. by lysis
• CPC Class Codes: C02F 2303/10 Energy recovery
• CPC Class Codes: C02F 9/00 Multistage treatment of water, waste water or sewage
• CPC Class Codes: F01K 17/04 for specific purposes other than heating F01K17/06 takes precedence
• CPC Class Codes: F01K 17/06 Returning energy of steam, in exchanged form, to process, e.g. use of exhaust steam for drying solid fuel or plant
• CPC Class Codes: F01K 25/04 the fluid being in different phases, e.g. foamed
• CPC Class Codes: F22B 31/0007 with combustion in a fluidized bed fluidized bed apparatus per se B01J8/00; fluidized bed combustors F23C10/00
• CPC Class Codes: F23G 5/04 drying
• CPC Class Codes: F23G 5/30 having a fluidised bed
• CPC Class Codes: F23G 5/40 : Portable or mobile incinerators
• CPC Class Codes: F23K 1/04 : Heating fuel prior to delivery to combustion apparatus
• CPC Class Codes: F23K 2201/20 : Drying
• CPC Class Codes: Y02E 20/12 : Heat utilisation in combustion or incineration of waste
• CPC Class Codes: Y02E 50/10 : Biofuels, e.g. bio-diesel
• CPC Class Codes: Y02E 50/30 : Fuel from waste, e.g. synthetic alcohol or diesel
• CPC Class Codes: Y02W 10/30 : Wastewater or sewage treatment systems using renewable energies
• CPC Class Codes: Y02W 10/40 : Valorisation of by-products of wastewater, sewage or sludge processing

Abstract

At least one aspect of the technology provides a self-contained processing facility configured to convert organic, high water-content waste, such as fecal sludge and garbage, into electricity while also generating and collecting potable water.

Claims

1. A fecal waste processing system for electricity and potable water generation, comprising:

a steam-powered electricity generation system comprising a boiler assembly, a steam engine, and a condenser interconnected and having a primary water circuit that carries primary water through the boiler assembly, steam engine assembly, and condenser, wherein operation of the steam engine assembly generates electricity;

a fecal sludge system that receives at least a portion of the electricity generated from the steam engine assembly, the fecal sludge system comprising a sludge dryer assembly and a sludge delivery system configured to deliver wet fecal sludge to the sludge dryer assembly, wherein the condenser is coupled to the sludge dryer assembly and configured to deliver first heat to the wet fecal sludge to vaporize first sludge water from the fecal sludge and to dry solid fuel material in the fecal sludge;

a water collection system connected to the sludge dryer assembly and configured to receive and condense the vaporized first sludge water for collection in a collection portion as clean, liquid water; and

a combustor system connected to the fecal sludge system and the boiler of the electricity generation system, the combustor system comprising a combustor configured to burn the dry solid fuel material from the fecal sludge system and provide heat to the primary water circuit in the boiler assembly, wherein the boiler assembly provides steam to the steam engine.

2. The system of claim 1 wherein the sludge dryer assembly is a two-stage dryer sequential having first and second dryer stages, wherein the first dryer stage generates the vaporized sludge water from the sludge, and the second dryer stage uses the vaporized sludge water from the first dryer stage to dry the sludge.

3. The system of claim 1 wherein the sludge dryer assembly comprises sequential first and second dryer stages, where the first dryer stage receives a substantially continuous flow of fecal sludge from the sludge delivery system and provides a substantially continuous flow of partially dried thickened fecal sludge to the second dryer stage, and the second dryer stage provides substantially dried solid fuel material to the combustor, and wherein water from the first and second dryer stages is provided to the water collection system.

4. The system of claim 1 wherein the sludge dryer having a rotatable advancing assembly within a housing, the rotatable advancing assembly being configured to move the fecal sludge axially through the housing as the fecal sludge is dried.

5. The fecal waste processing system of claim 1 wherein the combustor system is a fluidized bed combustor assembly.

6. The fecal waste processing system of claim 1 wherein the steam-powered electricity generation system, the fecal sludge system, the water collection system, and the combustor system are mounted on a frame and transportable with the frame as a unit.

7. The fecal waste processing system of claim 1 wherein the steam-powered generator is a single action, liquid cooled steam engine.

8. The fecal waste processing system of claim 1 wherein the fecal sludge system comprises a rotatable heated auger that engages the fecal sludge, advances the fecal sludge through the fecal sludge system and delivering at least some of the first heat to the fecal sludge.

9. A multifunctional wet waste processing system for generating electricity and clean water generation, comprising:

a sludge dryer assembly having a waste path with a sludge inlet configured to receive wet sludge comprising a mixture of water and solid waste material, the sludge dryer assembly having a drying portion configured to dry the sludge and separate at least some of the water from the solid waste material to provide dried solid fuel, the sludge dryer assembly having a first water outlet, a dry waste outlet, and a condenser portion having a fluid path with a fluid inlet and a first fluid outlet, the fluid path being isolated from the waste path;

a clean water collection system coupled to the first water outlet and configured to collect the separated water from the sludge;

a dry waste combustor assembly coupled to the dry waste outlet of the sludge dryer assembly, the dry waste combustor assembly having a combustion portion that receives the solid fuel from the dry waste outlet and burns the solid fuel and generates heat, and the dry waste combustor assembly having a boiler heated by the heat from the combustion portion burning the solid fuel, the boiler having a first water inlet and a first steam outlet;

a steam-powered generator coupled to the first steam outlet of the boiler and configured to generate electricity, the generator having a second fluid outlet coupled to the fluid inlet of the condenser portion; and

a water pump having a second water inlet coupled to the fluid outlet of the condenser portion, wherein the water pump is coupled to the first water inlet and wherein the boiler is configured to convert a flow of water entering the boiler to a flow of steam to power the steam-powered generator.

10. The system of claim 9 wherein the drying portion of the sludge dryer assembly comprises a steam-heated auger in the waste path and configured to move and heat the sludge during the drying process.

11. The system of claim 9 wherein the waste dryer assembly is a multi-segment dryer having sequential first and second dryer segments each coupled to the condenser portion and each configured to dry the sludge by vaporizing water from the sludge using heat from exhaust steam from the steam-powered generator.

12. The system of claim 11 wherein the first dryer segment generates first dryer water from water separated from the sludge, and the second dryer segment has a first water carrier portion coupled to the first dryer segment and configured to carry the first dryer water adjacent to and isolated from the sludge in the second dryer segment, and the second dryer segment having a second water carrier portion isolated from the first water carrier portion and configured to carry the exhaust steam from the steam-powered generator adjacent to the sludge, wherein heat from the first and second water carrier portions dries the sludge moving therein.

13. The system of claim 9 wherein the waste dryer assembly is configured to receive in the condenser portion exhaust steam from the steam-powered generator, the drying portion having a first segment connected to the sludge inlet and has a first heater portion coupled to the condenser and configured to vaporize a first portion of the water from the sludge with heat from the exhaust steam, and a second dryer segment connected in series to the first dryer segment and configured to vaporize a second portion of the water from thickened sludge received from the first dryer segment with heat from the exhaust steam.

14. A multifunctional wet organic sludge processing system, comprising:

a sludge dryer assembly having a sludge inlet configured to receive sludge comprising a mixture of water and solid organic waste material, the sludge dryer assembly having a drying portion with a housing and a sludge advancing assembly in the housing, wherein the sludge advancing assembly is rotatable to cause the wet sludge to move within the housing along a waste path, the sludge dryer assembly having a heating portion adjacent to the waste path and configured to dry the sludge and thermally separate at least some of the water from the solid waste material to provide dried solid fuel, the sludge dryer assembly having a first steam inlet and a first steam outlet and a dry waste outlet;

a combustor assembly coupled to the dry waste outlet of the sludge dryer assembly, the combustor assembly having a combustion portion that receives the solid fuel from the dry waste outlet and burns the solid fuel to generate heat, and the combustor assembly having a boiler heated by the heat from burning the solid fuel, the boiler having a first water inlet and a second steam outlet;

a steam-powered generator coupled to the second steam outlet of the boiler and configured to generate electricity, the generator having a water outlet coupled to the first steam inlet of the sludge dryer assembly, wherein steam from the generator enters the first steam inlet, remains isolated from the sludge in the waste path and vaporizes the water in the sludge moving in the drying portion; and

a water pump having a second water inlet coupled to the water outlet of the steam-powered generator, wherein the water pump is coupled to the first water inlet, and the boiler is configured to convert a flow of water entering the boiler to a flow of steam to power the steam-powered generator.

15. The system of claim 14, further comprising a condenser coupled between the sludge dryer assembly and the boiler, wherein the condenser is configured to receive steam from the sludge dryer assembly and provide liquid water to the boiler.

16. The system of claim 14, further comprising a clean water collection system coupled to the first steam outlet and configured to collect the water thermally separated from the wet sludge.

17. The system of claim 14 wherein the sludge advancing assembly is a steam-heated auger in the waste path configured to move and heat the sludge during the drying process.

18. The system of claim 14 wherein the waste dryer assembly is a multi-segment dryer having sequential first and second dryer segments each configured to dry the sludge by vaporizing water from the sludge using heat from exhaust steam from the steam-powered generator.

19. The system of claim 18 wherein the first dryer segment generates first dryer water from water separated from the sludge, and the second dryer segment has a first water carrier portion coupled to the first dryer segment and configured to carry the first dryer water adjacent to and isolated from the sludge in the second dryer segment, and the second dryer segment having a second water carrier portion isolated from the first water carrier portion and configured to carry the exhaust steam from the steam-powered generator adjacent to the sludge, wherein heat from the first and second water carrier portions dries the sludge moving therein.

20. A sludge processing system for clean water generation, comprising:

a sludge dryer assembly having a dryer housing with a sludge inlet configured to receive a flow of sludge along a waste path, the sludge comprising a mixture of water and solid waste material, the sludge dryer assembly having a heater system coupled to the dryer housing and having a vapor path adjacent to and isolated from the waste path the heater system being configured to heat the sludge in the dryer housing and thermally separate vapor from the solid waste material to provide dried waste material, the dryer housing having a vapor outlet and a solid fuel outlet, the heater system having a vapor inlet and a water outlet; and

a vapor collection assembly connected to the vapor outlet of the dryer housing to receive the vapor thermally separated from the solid waste material, and the vapor collection assembly being connected to the vapor inlet of the heater system and configured to direct the vapor from the dryer housing into the heater to heat the sludge moving along the waste path in the dryer housing; and

a water collection system connected to the water outlet of the heater system and configured to carry water in vapor and/or liquid phase away from the heater system.

21. The sludge processing system of claim 20 wherein the sludge dryer assembly is a two-stage dryer having sequential first and second dryer stages, wherein the heater system comprises a first heater formed as part of the first dryer stage and a second heater formed as part of the second dryer stage, wherein the first dryer stage heats the sludge to provide thickened sludge to the second dryer stage, wherein the second dryer stage heats the thickened sludge to form the dried waste material, wherein the first dryer stage includes the vapor outlet, and wherein the second heater includes the vapor inlet that receives the vapor from the vapor collection assembly and uses the vapor to heat the sludge provided to the second stage drying.

22. The sludge processing system of claim 20, further comprising:

a combustor assembly coupled to the solid fuel outlet of the dryer housing and configured to receive the dried waste material from the second dryer stage, the combustor assembly having a combustor configured to receive and burn the dried solid waste material, and having a boiler configured to receive heat from the combustor;

a primary water circuit that carries primary water to the boiler which heats the primary water to form steam, wherein the boiler comprises a first steam outlet; and

a power plant comprising a steam engine and a generator driven by the steam engine, the steam engine being coupled to the first steam outlet to receive steam therefrom, the generator being configured to generate electricity, the first heater having a fluid path with a steam inlet and a fluid outlet, the steam powered generator exhausts steam into the fluid path using the steam inlet, wherein heat from the exhausted steam in the fluid path boils the water in the sludge to form the thickened sludge, wherein the steam in the fluid path is condensed into a liquid, and wherein the boiler receives the liquid over the fluid outlet and is configured to convert the liquid water into steam to power the generator.

23. The sludge processing system of claim 20 wherein the sludge dryer assembly comprises a sludge advancing assembly rotatably positioned in the dryer housing and move the sludge along the waste path during the drying process.

24. The sludge processing system of claim 20 wherein the sludge advancing system is a vapor-heated auger in the waste path configured to heat the sludge moving along the waste path during the drying process.