WO2009111791A2

WO2009111791A2 - Landfill waste remediation process

Info

Publication number: WO2009111791A2
Application number: PCT/US2009/036557
Authority: WO
Inventors: Richard C. Jackson
Original assignee: Capital Technologies, Inc.
Priority date: 2008-03-07
Filing date: 2009-03-09
Publication date: 2009-09-11
Also published as: WO2009111791A3

Abstract

A method of remediating landfill waste comprising mining the waste from a landfill, screening the waste, shredding the waste, magnetically separating ferrous metals from the waste, performing a solid distillation de-polymerization process on the waste to produce hydrocarbon gas (plus water vapor and dry solid waste), distilling the hydrocarbon gas to produce hydrocarbon liquid (which can be processed into synthetic fuel), recycling hydrocarbon gas to produce heat to operate the solid distillation process, and cracking and hydrotreating the hydrocarbon liquid to produce synthetic fuel. In one embodiment, the method further comprises recovering non-ferrous metals from the dry solid waste. Preferably, the method further includes performing an ultra-high temperature gasification process to the dry solid waste to produce inorganic material (which can be returned to the landfill) and a hydrocarbon gas (which can be recycled to produce heat for the method).

Description

LANDFILL WASTE REMEDIATION PROCESS

FIELD OF INVENTION

[0001] The present invention relates to techniques of waste remediation, processing, and recycling.

BACKGROUND

[0002] In a world ever increasing in population, with a finite amount of natural resources and a finite amount of habitable land, a process and system to mine and extract significant quantities of essential industrial materials from what had previously been thought of as waste deposits is desirable. Landfills and industrial dumps must be re-characterized as important deposits of highly concentrated materials, which are by definition the very materials that are consumed by mankind in the course of their everyday lives.

[0003] Various methods concerning recycling of waste and the conversion of waste into energy are known. There is a need for waste remediation systems that are able to handle all types of waste and can recycle nearly all constituents of the waste with low environmental impact.

SUMMARY OF THE INVENTION

[0004] The present invention provides a landfill waste remediation process that effectively extracts and recycles substantially all valuable constituents from landfills, while simultaneously reclaiming the landfill space, removing a dangerous source of groundwater contamination and greenhouse gases (methane leakage from aging landfills), and producing energy to run the process. The result is a process that converts waste (e.g., municipal solid waste, waste water sludge, coal mine tailing, industrial wastes, etc.) into recaptured metals, minerals and carbon compounds without the need to inefficiently burn the waste and thus without producing substantial amounts of smoke or other environmental contaminants. Utilizing the present invention, existing landfill sites can be economically mined and remediated for much higher and better use.

[0005] In one aspect, the process starts by mining, screening, and shredding the waste and magnetically separating the ferrous metals. The waste is then run through a solid distillation de-polymerization process to produce hydrocarbon gas, water vapor, and dry solid waste. The water vapor is distilled, and the resulting liquid water is treated and properly disposed of or used. Undistilled (e.g., non-condensable) hydrocarbon gas can be recycled and used to run generators or produce heat to operate the solid distillation process. Distilled de-polymerized hydrocarbon liquid can be sold for industrial, commercial, or residential use. In addition the hydrocarbon liquid can be cracked and hydrotreated to produce a valuable synthetic fuel and other products.

[0006] The dry solid waste from the solid distillation process is then processed in order to recover any desired non-ferrous metals. The resulting solid waste can then be subjected to an ultra-high temperature gasification process, which produces inorganic material and a hydrocarbon gas and/or mixed with coal for power generation, thereby reducing demand for freshly mined coal. The inorganic material can be returned to the landfill, further processed to extract valuable metals and elements, or sold for industrial use. The hydrocarbon gases can be recycled and used to run generators or produce heat to operate the process. In addition, the hydrocarbon gases can be sold for industrial, commercial, or residential use, or the hydrocarbon gas can be treated with gas-to-liquids technology (e.g., Fischer-Tropsch process or Mobil process, as is well-known in the art) to produce a valuable synthetic fuel, and other products.

[0007] In a preferred embodiment, the present invention would result in a process that reuses substantially all of the waste, and has substantially no material placed into, or back into, a landfill. That is, all material put into the process would be processed and reused for some purpose, resulting in a zero or near zero (e.g., less than 10%, 5%, 1%, etc. of input mass) waste process.

[0008] Variations of the above-described process can be utilized. For example, certain steps can be added or removed from the above-described process and/or the above process steps can be performed in a different order. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The attached figure is a diagram depicting a process for remediating landfill waste embodying one or more aspects of the present invention.

DETAILED DESCRIPTION

[0010] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including," "comprising," or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.

[0011] The invention provides, among other things, a waste remediation process that efficiently recycles and reuses all waste constituents in existing landfills and new waste streams. The process utilizes all materials from the waste, and recovers energy and usable hydrocarbon fuels from the waste.

[0012] Many types of waste may be treated by the process described herein, such as municipal waste, waste comprised of materials used in our daily lives, industrial waste, waste produced from industrial processes, medical waste, waste from hospitals and clinics that may be contaminated with body fluids and fecal matter, waste water sludges, coal mining tailings, and the like. The major components of these types of wastes are organic waste. The process effectively extracts and recycles valuable constituents from the waste, and also produces its own energy from the waste, facilitating the recapture and beneficial and environmentally- sound reuse of metals, minerals and carbon compounds present in the waste. If widely used, this will dramatically reduce the demand for new production of scarce resources, extending the earth's limited natural mineral and energy reserves for future generations.

[0013] An outline of the processes performed in the waste remediation system is diagramed in the figure. The process includes the intake of waste into the facility. The material may be delivered to the facility by conveyor, truck, a slurry pipeline or a combination thereof. Existing landfill waste can be excavated using standard mining equipment, with material conveyed to a screening system to separate out dirt by mechanical and cyclone systems, and then conveyed to the system. After the waste is taken into the facility, the waste is fed into a shredder, and then through a magnetic processing system to remove any ferrous metals preferably by a separation conveyor. These ferrous metals are accumulated and recycled.

[0014] The non-ferrous waste is processed using a solid distillation de-polymerization process, preferably a continuous -flow, low-oxygen, heated auger, or rotary kiln technology. This process includes moving the non-ferrous waste through a closed, oxygen- free heated chamber, either continuously or in batches. Within the chamber, the waste is heated to high temperatures (about 750°F) in the absence of oxygen to de-polymerize the plastic compounds and separate by vaporization the moisture and volatiles (e.g., hydrocarbon vapors) from the solid waste. A series of condensers operate under a vacuum pressure such that hydrocarbon vapors and moisture are drawn to the condensers. The hydrocarbon and moisture vapors are condensed and collected for further processing. Solid distillation processes are described in US Patent Application Nos. 11/320,936 and 11/704,627, which are incorporated herein by reference in their entirety.

[0015] The condensed liquids collected include water and hydrocarbon liquids. These materials are separated into water and hydrocarbon gases by gravity separation, and/or by the use of liquid/liquid separation or polymer processes. Recovered water is treated if necessary to meet local discharge standards, used for agricultural irrigation, treated by reverse osmosis to provide potable water or a combination thereof. The hydrocarbon gases recovered are further distilled into a hydrocarbon liquid and separated from the undistilled gases. The undistilled gases may be used as a fuel source to run generators to produce energy or to create the heat required for the solid de-polymerization distillation process described above.

[0016] The distilled hydrocarbon liquid has many uses. The hydrocarbon liquid may be further used as a source of "renewable" heating oil for power generation and/or heating and sold for industrial, commercial or residential use. The distilled hydrocarbon liquids may also be used as diluents for the oil industry. Further, the hydrocarbon liquids may be cracked and hydrotreated to produce usable refined synthetic fuels such as diesel, kerosene, and other renewable transportation fuels and other commercial products. Methods of producing refined synthetic fuels are known in the art, and such methods are described in U.S. Patent Application Nos. 10/274,403, 10/273,384, and 10/273,390, which are incorporated herein by reference in their entirety.

[0017] The solid waste produced from the solid distillation processes described above, consists of a combination of sterile inert material metals, carbon and carbon compounds. This remaining solid waste is commonly about 20%-40% of the original mass and less than about 10% of the original volume. A simple screening and/or cyclone system extracts non- ferrous metals such as aluminum, copper and cobalt from the non-distilled solids. These non- ferrous metals are accumulated and recycled. The remaining material may be land filled using much less space than the original waste, used as a filler to produce structural or cosmetic components (e.g., blocks, bricks, composite members), mixed with coal or burned directly for heat and/or power generation, or treated by an ultra-high temperature gasification steam-shift process, or a combination thereof.

[0018] Ultra-high temperature gasification is described in U.S. Patent No. 5,464,454. This process produces very few if any harmful admissions by applying indirect thermal energy in the absence of oxygen to reduce materials to a combustible gas and a non- hazardous, non-leachable inorganic material. The ultra-high temperature gasification process converts the carbon and carbon compounds of the solid waste into hydrogen and carbon synthetic gas and inert inorganic material. The hydrogen and carbon gases are scrubbed to remove sulfur or chloride compounds or any residual metals. The clean gases may contain from about 50% hydrogen and from about 50% carbon compounds, such as carbon monoxide. The clean gases are able to be processed using gas-to-liquid technology to produce synthetic fuels or safely combusted to provide heat and/or power to run other processes such as the solid distillation process described above. The synthetic fuels may be sold for industrial, commercial or residential use. The other gasification byproduct, inert inorganic material, may contain a combination of industrial metals, e.g. copper, aluminum, brass and chromium, precious metals, e.g. gold, platinum, and silver, as well as other noble metals and valuable elements, e.g. cobalt. In addition, the inert inorganic material has some lower value elements such as silicon, and the like. Various chemical and mechanical techniques may be used to concentrate and extract these various materials for capture and recycling.

Claims

What is claimed is:

1. A method of remediating landfill waste comprising: mining the waste from a landfill; screening the waste; shredding the waste; magnetically separating ferrous metals from the waste; performing a solid distillation de-polymerization process on the waste to produce hydrocarbon gas, water vapor, and dry solid waste; distilling the hydrocarbon gas to produce hydrocarbon liquid; recycling hydrocarbon gas to produce heat to operate the solid distillation process; and cracking and hydrotreating the hydrocarbon liquid to produce synthetic fuel.

2. The method of claim 1, further comprising recovering non-ferrous metals from the dry solid waste.

3. The method of claim 1, further comprising performing an ultra-high temperature gasification process to the dry solid waste to produce inorganic material and a hydrocarbon gas.

4. The method of claim 3, further comprising returning the inorganic material to the landfill.

5. The method of claim 1, recycling the hydrocarbon gas from the ultra-high temperature gasification process to produce heat for any of the processes of the method.

6. The method of claim 1, further comprising treating the hydrocarbon liquid to produce synthetic fuel.

7. A method of remediating waste comprising: providing the waste; magnetically separating ferrous metals from the waste; performing a solid distillation de-polymerization process on the waste to produce hydrocarbon gas, water vapor, and dry solid waste; distilling the water vapor; recycling hydrocarbon gas from the solid distillation de-polymerization process to produce heat to operate the solid distillation process; and cracking and hydrotreating hydrocarbon liquid to produce synthetic fuel.

8. The method of claim 7, further comprising recovering non-ferrous metals from the dry solid waste.

9. The method of claim 7, further comprising performing an ultra-high temperature gasification process to the dry solid waste to produce inorganic material and a hydrocarbon gas.

10. The method of claim 9, further comprising returning the inorganic material to the landfill.

11. The method of claim 9, further comprising recycling the hydrocarbon gas from the ultra-high temperature gasification process to produce heat for any of the processes of the method.

12. The method of claim 9, further comprising distilling the hydrocarbon gas to produce hydrocarbon liquid, and treating the hydrocarbon liquid to produce synthetic fuel.

13. A method of remediating waste comprising: providing the waste; performing a solid distillation de-polymerization process on the waste to produce hydrocarbon gas, water vapor, and dry solid waste; performing an ultra-high temperature gasification process to the dry solid waste to produce inorganic material and a hydrocarbon gas.

14. The method of claim 13, further comprising recovering non-ferrous metals from the dry solid waste from the solid distillation de-polymerization process.

15. The method of claim 13, further comprising recycling hydrocarbon gas from the solid distillation de-polymerization process to produce heat to operate the solid distillation process.

16. The method of claim 13, further comprising distilling the water vapor from the solid distillation de-polymerization process.

17. The method of claim 13, further comprising: distilling the hydrocarbon gas to produce hydrocarbon liquid; and cracking and hydrotreating the hydrocarbon liquid to produce synthetic fuel.

18. The method of claim 13, further comprising recycling the hydrocarbon gas from the ultra-high temperature gasification process to produce heat for any of the processes of the method.