Abstract:
A system for extracting metals (e.g. precious metals or dangerous metals) from a substrate material such as sludge from a lake bed or sewage treatment facility includes processing the substrate material and metals by exposing the substrate material and metals to the plasma of an electric arc. Then, the exposed substrate material and metals are passed through an electrically charged collection grid in which the metals, now electrically charged, are attracted to the collection grid and hold to the collection grid and the substrate material exits the collection grid with less concentrations (or none) of the metals. In some embodiments, in addition to recovering the metals (e.g. precious metals, dangerous metals, etc.), a flammable gas is produced.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. provisional application No. 61/988,973 filed on May 6, 2014, the disclosure of which is incorporated by reference. 
     
    
     FIELD 
       [0002]    This invention relates to the field of reclamation and more particularly to a system, method and apparatus for reclaiming metals such a precious or toxic metals. 
       BACKGROUND 
       [0003]    There are many instances in which precious metals or toxic metals are suspended in a material. There are many bodies of water (e.g., lake beds, river beds, sewage, and sludge) in which precious metals or toxic metals are suspended within silt and water forming, for example, sludge. Likewise, effluent from certain mining or processing operations includes some concentration of precious metals or toxic metals such as the metals that are being mined. With prior technology, it was not cost effective to extract the precious metals or toxic metals from these material so the material remains, in some cases, polluting the area around where the material is present (e.g. cadmium and lead suspended in sludge in a lake bed). 
         [0004]    Often there is value to these materials if sufficient quantity is extracted from the sludge, but prior systems were incapable of a cost-effective extraction of precious metals or toxic metals, especially when such precious metals or toxic metals are suspended in low concentrations. 
         [0005]    What is needed is a system that will extract metals that are suspended in a material such as sludge or water. 
       SUMMARY 
       [0006]    A system for extracting metals (e.g. precious metals or dangerous metals) from a substrate material such as sludge from a lake bed or sewage treatment facility includes processing the substrate material and metals by exposing the substrate material and metals to the plasma of an electric arc. Then, the exposed substrate material and metals are passed through an electrically charged collection grid in which the metals, now electrically charged, are attracted to the collection grid and hold to the collection grid and the substrate material exits the collection grid with less concentrations (or none) of the metals. In some embodiments, in addition to recovering the metals (e.g. precious metals, toxic metals, etc.), a flammable gas is produced. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: 
           [0008]      FIG. 1  illustrates a schematic view of an exemplary system for recovering metals. 
           [0009]      FIG. 2  illustrates a schematic view of an exemplary system for recovering metals. 
           [0010]      FIG. 3  illustrates a schematic view of an exemplary controller of a system for recovering metals. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures. 
         [0012]    Throughout this description, system for recovering metals  5  is described as a system for processing a material that contains suspended particles of metals such as silver and gold or toxic metals or materials such as cadmium. For simplification, this source material will be referred to as sludge  8  as in sludge that is often found on the floor of water bodies, though any material is anticipated for processing by the system for recovering metals  5 . Another example of such material is solvents used in processing integrated circuits and circuit boards, etc. Another example of such material is effluent from mining operations. 
         [0013]    Referring to  FIGS. 1 and 2 , exemplary systems  5 / 5 A for recovering metals such as precious metals or toxic metals are shown. In addition to recovering such metals (e.g. precious metals or toxic metals), in some embodiments, a flammable gas  24  is also produced. The systems for recovering precious metals  5 / 5 A are examples of systems  5 / 5 A for recovering precious metals, as other such systems  5 / 5 A and configurations are also anticipated. The recovery on metals from the sludge  8  starts with exposing the sludge  8  to a plasma  18  of an electric arc. The sludge  8  is pumped through a valve  52  by a feed pump  50  and into the reactor  12  where it is known as feedstock  22 . The electrodes  14 / 16  and plasma  18  of the arc are submerged within the feedstock  22  as the feedstock is circulated within the reactor  12  and re-injected into the plasma  18  of the electric arc between the two electrodes  14 / 16 . The plasma  18  causes the feedstock  22  to react, depending upon the composition of the feedstock  22  and the composition of the electrodes  14 / 16  used to create the arc. 
         [0014]    The electrodes  14 / 16  are made of any known conductive material or materials. In some embodiments, one or both electrodes  14 / 16  are made of a sacrificial material (e.g. carbon), in that, some portion of the electrode(s)  14 / 16  is sacrificed and combined with atoms/molecules of the feedstock  22  to form a gas  24 , typically a combustible gas  24 . In some embodiments, one or both electrodes  14 / 16  are made from a material (e.g. a metal such as copper, tungsten, steel, etc.) that does not readily sacrifice atoms to the arc and, therefore, require less adjustment and replacement. In some embodiments, one electrode  14 / 16  is made of a sacrificial material (e.g. carbon) while the other electrode  14 / 16  is made of a non-sacrificial material (e.g. copper). 
         [0015]    Any feedstock  22  containing any amount of metals (e.g., precious metals or toxic metals) is anticipated either in fluid form or fluid mixed with solids, preferably fine-grain solids such as gold dust, etc. The gas  24  produced in this process is typically combustible and the composition of the gas  24  is dependent upon the fluid base of the feedstock  22  and the composition of the electrodes  14 / 16 . 
         [0016]    In examples in which the feedstock  22  is a petroleum-based liquid having there within precious metals, the exposure of this petroleum-based feedstock  22  to the arc (as above) results in a gas that includes polycyclic aromatic hydrocarbons which, in some embodiments, are quasi-nanoparticles that are not stable and, therefore, some of the polycyclic aromatic hydrocarbons will form/join to become nanoparticles or a liquid. Therefore, some polycyclic aromatic hydrocarbons as well as some carbon particles/nanoparticles are present in the resulting gas  24 . In some embodiments, some of the carbon particles or nanoparticles are trapped or enclosed in poly cyclic bonds. Analysis of the produced gas  24  typically includes polycyclic aromatic hydrocarbons that range from C 6  to C 14 . The presence of polycyclic aromatic hydrocarbons as well as carbon particles or nanoparticles contributes to the unique burn properties of the resulting gas  24 . This leads to higher burning temperatures. 
         [0017]    In another example, the feedstock  22  is used motor oil and at least one of the electrodes  14 / 16  are carbon. In this, the petroleum molecules separate within the plasma of the electric arc  18  into a gas  24  that includes hydrogen (H 2 ) and aromatic hydrocarbons, which percolate to the surface of the petroleum liquid  22  for collection. In some embodiments, the gas  24  produced though this process includes suspended carbon particles since at least one of the electrodes of the arc  18  is made from carbon and serves as the source for the charged carbon particles or nanoparticles that travel with the manufactured hydrogen and aromatic hydrocarbon gas  24  and are collected along with, for example, the hydrogen and aromatic hydrocarbon molecules, thereby changing the burning properties of the resulting gas  24 , leading to a hotter flame. In this example, if the feedstock  22  is used motor oil and the fluid/gas  24  collected includes any or all of the following: hydrogen, ethylene, ethane, methane, acetylene, and other combustible gases to a lesser extent, plus suspended charged carbon particles or nanoparticles that travel with these gases. Used motor oil often has fine grain particles of metal suspended there within. Although such metals are typically not valuable for recovery, in some instances, it is important to remove these particles of metal during the processing of used motor oil, while in other instances, such metals are of importance depending upon the metals of the motor in which such used motor oils was used. 
         [0018]    For simplicity, the produced gas  24  is shown being collected in a tank  30  for later use. 
         [0019]    In operation, the circulation valve  52  is set to open by the controller  40 , connecting the source of sludge  8  to the pump  50  and the pump  50  is controlled to operate and fill the reactor  12  to a certain level with feedstock  22 . As the process continues, it is anticipated that the above is repeated as the feedstock  22  depletes, e.g., as the gas  24  is produced. Note, at this time the exit valve  62  is closed so that no feedstock  22  exits the reactor  12 . 
         [0020]    Once sufficient feedstock  22  is within the reactor  12 , the valve  52  is controlled by the controller  40  to circulate and the feedstock  22  is pumped from the reactor  12  through a feed pipe/tube  56  and back out through an injection pipe  54  by the circulation pump  50 . This flow is directing the circulation of feedstock  22  directly into the plasma  18  of the arc between the electrodes  14 / 16 . In some embodiments, the flow of the feedstock  22  is directed through one or both of the electrodes  14 / 16  for better positioning within the plasma  18 . 
         [0021]    In the system  5  of  FIG. 1 , when sufficient feedstock  22  has been exposed to the plasma  18  of the arc, the exit valve  62  is opened and the exit pump  60  is operated to pump some or all of the processed feedstock  22  out of the reactor through an exit pipe/tube  64 . The feedstock  22  that has been exposed to the plasma  18  then passes through one or more plates  68  of a collection grid  66 . Each of the plates is electrically charged, either positively or negatively with respect to the feedstock  22  that has been exposed to the plasma  18 . During exposure to the plasma  18  of the arc, the suspended metal particles (e.g. suspended precious metal particles or suspended toxic metal particles) gain or lose electrons and, therefore, become either positively or negatively charged. As the charged suspended metal particles (e.g. suspended precious metal particles or suspended toxic metal particles) pass close to the plates  68  of the collection grid  66 , by nature of such charge with respect to the specific charge on the plates  68 , the plates  68  attract the metal particles (or suspended metal particles) and the metal particles (e.g. suspended precious metal particles or suspended toxic metal particles) collect on the plates  68 . At some point, the system is shut down and the metal particles (e.g. suspended precious metal particles or suspended toxic metal particles) are removed (e.g., scraped) from the plate(s)  68 . 
         [0022]    In the system  5 A of  FIG. 2 , as the feedstock  22  is been exposed to the plasma  18  of the arc, some or all of the processed feedstock  22  passes through or close to one or more plates  68  of a collection grid  67 . Each of the plates  68  is electrically charged, either positively or negatively with respect to the feedstock  22  that has been exposed to the plasma  18 . During exposure to the plasma  18  of the arc, the suspended metal particles (e.g. suspended precious metal particles or suspended toxic metal particles) gain or lose electrons and, therefore, become either positively or negatively charged. As the charged suspended metal particles pass close to the plates  68  of the collection grid  67 , by nature of such charge with respect to the specific charge on the plates  68 , the plates  68  attract the metal particles (e.g. precious metal particles or toxic metal particles) which collect on the plates  68 . At some point, the system is shut down and the metal particles (e.g. suspended precious metal particles or suspended toxic metal particles) are removed (e.g., scraped) from the plate(s)  68 . 
         [0023]    After the metal particles are collected by the plate(s)  68  of a collection grid  66 / 67 , remaining material (e.g. sludge) exits the system through an outlet  70  for further processing. Such material that exits through the outlet  70  has less or no suspended metal particles as such have been extracted and attach to the plate(s)  68 . 
         [0024]    Note that, based upon the charge applied to the metal particles, it is anticipated that in some embodiments, the plate(s)  68  are positively charged while in some embodiments, the plate(s)  68  are negatively charged. In some embodiments, some plates  68  are positively charged and some plates  68  are negatively charged. 
         [0025]    In some embodiments, a solvent, thinner, or coagulant material  90  is mixed into the feedstock  22  under control of the controller  40 . In such, the material  90  improves adhesion of the suspended metal particles to the plates  68 , improves flow of the feedstock  22 , changes the specific gravity of the feedstock with respect to the suspended metal particles, etc., such that the precious metal particles either adhere better to the plates  68 , or fall to the bottom of the reactor  12 , or float to the top of the feedstock  22  for collection from the surface. 
         [0026]    Referring to  FIG. 3 , a schematic view of an exemplary controller  40  of a system  5 / 5 A for recovering precious metals is shown. This example computer system  40  represents a typical computer system  40  used to control various aspects of the system for recovering precious metals. The example computer system  40  is shown in its simplest form, having a single processor. Many different computer architectures are known that accomplish similar results in a similar fashion and the present invention is not limited in any way to any particular computer system. The present invention works well utilizing a single processor system, as shown in  FIG. 2 , a multiple processor system where multiple processors share resources such as memory and storage, a multiple server system where several independent servers operate in parallel (perhaps having shared access to the data or any combination). In any of these systems, a processor  170  executes or runs stored programs that are generally stored for execution within a memory  174 . The processor  170  is any processor or a group of processors, for example an Intel Pentium-4® CPU or the like. The memory  174  is connected to the processor by a memory bus  172  and is any memory  174  suitable for connection with the selected processor  170 , such as SRAM, DRAM, SDRAM, RDRAM, DDR, DDR-2, etc. Also connected to the processor  170  is a system bus  182  for connecting to peripheral subsystems such as a network interface  180 , persistent storage (e.g. a hard disk)  188 , removable storage (e.g. DVD, CD, flash drive)  190 , a graphics adapter  184  and a keyboard/mouse  192 . The graphics adapter  184  receives commands and display information from the system bus  182  and generates a display image that is displayed on the display  186 . 
         [0027]    In general, the persistent storage  188  is used to store programs, executable code and data such as user financial data in a persistent manner. The removable storage  190  is used to load/store programs, executable code, images and data onto the persistent storage  188 . These peripherals are examples of input/output devices  180 / 184 / 192 , persistent storage  188  and removable storage  190 . Other examples of persistent storage include core memory, FRAM, flash memory, etc. Other examples of removable media storage include CDRW, DVD, DVD writeable, Blu-ray, compact flash, other removable flash media, floppy disk, etc. In some embodiments, less devices or other devices are connected to the system through the system bus  182  or with other input-output connections/arrangements as known in the industry. Examples of these devices include printers; graphics tablets; joysticks; and communications adapters such as modems and Ethernet adapters. In such, any of the prior devices  184 / 188 / 190 / 180 / 192  are optionally present. 
         [0028]    Various components of the system for recovering precious metals  5  are controlled by the controller  40  such as the pumps  50 / 60 , the power supply  10 , the valves  52 / 62 , and the electrode moving mechanism(s)  17 . For example, the controller  40  instructs the power supply  10  to apply the required voltage to the collection grid  68  as the controller instructs the valve  62  to open and the pump  60  to initiate flow through the collection grid  68 . 
         [0029]    In systems  5 / 5 A in which a wide-area connection or connection to other system is needed, the network interface  180  connects the computer-based system to the network  110  through a link  178  which is, preferably, a high speed link such as a cable broadband connection, a Digital Subscriber Loop (DSL) broadband connection, a T1 line, or a T3 line. 
         [0030]    Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result. 
         [0031]    It is believed that the system and method as described and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.