CROSS REFERENCE TO RELATED APPLICATION

[0001] The present application claims priority to United States Patent Application No.

61/540,871 , filed September 29, 201 1 , in the name of Mark D. Tranter, and entitled MICROBIAL OIL REMOVAL SYSTEM, the entire contents of which are incorporated herein for all purposes.

FIELD

[0002] The present disclosure relates generally to the use of microbes for removing oil from parts. More particularly, the present disclosure relates to an automated parts cleaning system including an automatic and continuous oil removal system using an automated microbe supply and digester system for removing oil from parts.

DISCUSSION OF RELATED ART

[0003] It is generally known to use certain microbes for remediating oil to clean a part. Examples of systems for washing or removing oil from and other hydrocarbon-based substances from parts using microbes are generally disclosed in US Patent Nos. 6,019,1 10; 6,057,147; and 6,391 ,836 and U.S. Publication No. 2006/0278255. It is generally known to provide a microbial cleaning solution, a cleaning basin, a filter, and a reservoir for aerating and storing the cleaning solution. The cleaning basin is capable of only holding a limited number of parts and such parts must be manually located into and manually removed from the basin post-cleaning. Accordingly, the known systems have drawbacks because they have a limited amount of microbes in a tank and are incapable of continuously cleaning parts.

[0004] One system is the Bio-Circle system (www.biocircle.com) available from

Walter Surface Technologies, Pointe-Claire, Quebec, Canada, which has limited performance capability, including a basin size of only 38 X 27 inches and a total system capacity of approximately 37 gallons of microbial cleaning solution. The performance results for such a system are very limited and incapable of use in a production environment where a significant number of parts are effectively continuously manufactured. For example, in one production facility, certain parts are manufactured in a progressive stamping die at the rate of hundreds (and preferably even thousands) of parts/hour to achieve a total production of millions of parts per annum. It is generally known that it is necessary to use oil in the stamping die for manufacturing the parts. The oil for use in a stamping die for use in stamping (or producing) a part is generally known as a stamping oil. However, in the known systems, the stamping oil is removed from the part in an oil removal process using a heated water bath and air-knife blades, etc such that the stamping oil ends up contaminating the heated water. The existing automated systems oil removal require washers that must typically operate at about 90°C or higher, requiring substantial energy costs (for using electricity or other power source) to maintain the temperature of the water. The existing systems further generally require the use of toxic heavy alkaline cleaners and typically produce massive amounts of wastewater, both of which must be disposed of according to stringent environmental regulations. The prior art systems have long been known as evidenced by U.S. Patent Nos. 3,930,897; 4,565,583; and 5, 143, 102. While such systems have been known for quite some time, there use continues unabated along with their drawbacks and problems of wasted water and energy (as well as other environmental issues). Accordingly, there long remains a significant need for a system that avoids such problems while still performing the necessary functions and objectives needed in the manufacturing process. Despite this significant and long felt need, no such system has been successfully developed or implemented.

SUMMARY

[0005] The present disclosure addresses one or more of the above needs by providing an automated and continuous system for the removal of organic matter from parts using a microbial cleaning solution. The system includes a plurality of tanks and filters in fluid communication with one another to continuously reuse the microbial cleaning solution. A control system is disclosed for controlling the various inputs (water, turbidity, microbe supply, parts) of the system based upon sensed conditions of the automated and continuous system and its outputs (water, O2 level, pH level, microbial biosensor, parts)

[0006] The system includes a submersion tank and a microbial cleaning solution, at least a portion of which is located within the submersion tank. The system further includes a conveying structure traveling through the portion of microbial cleaning solution located within the submersion tank. A filter system is located adjacent and in fluid communication with the submersion tank. The filter system leads to one or more digester portions located adjacent and in fluid communication with the filter system. The digester portion may include a plurality of angled platforms for receiving microbial cleaning solution that travels through the filter system and into the digester portion. A recovery tank is included within the system for receiving digested microbial cleaning solution that has passed through the digester portion. The recovery tank includes a means for transporting digested microbial cleaning solution form the recovery tank to the submersion tank. The system may further include one or more communicating and monitoring means. At least one monitor is included for determining the current level of microbial activity within the submersion tank. In addition, at least one communication means is included for causing the transport of digested microbial cleaning solution from the recovery tank to the submersion tank when the monitor indicates that the level of microbial activity in the submersion tank has fallen below a predetermined value.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Fig. 1 is a partial, cross-sectional, graphic view of an exemplary system in accordance with the present disclosure.

[0008] Fig. 2 is a partial, cross-sectional, graphic view and flow diagram of an exemplary digester portion of a system in accordance with the present disclosure.

[0009] Fig. 3 is a cross-sectional graphic view depicting exemplary connection pathways of a system in accordance with the present disclosure.

DETAILED DESCRIPTION

[0010] In general, the present disclosure and teachings described herein provide for a continuous parts cleaning system that utilizes a microbial cleaning solution for the removal of organic matter from parts.

[0011) The microbial cleaning solution preferably contains microbes that are capable of metabolizing organic material, namely hydrocarbons. A preferred cleaning solution removes oil, grease, soot, wax, protein, and other materials that are generally not removable with standard cleaning processes. Examples of suitable microbial cleaning solutions are available from Walter Surface Technologies, Pointe-Claire, Quebec, Canada. The microbial cleaning solution is capable of being recovered and re-used to reduce waste. In addition, the microbial cleaning solution is substantially non-toxic and non-flammable.

[0012] In a system devoted to aerobic bacterial metabolism, specific bacteria are selected having improved degradative abilities when exposed to an oxygen source. Such bacteria may include species from the genera Pseudomonas, Sphingomonas, Rhodoccus, Mycobacterium, Bacillus, Flavohacterium, Alcanivorax, and other species known in the art as effective in hydrocarbon bioremediation. In a system devoted to anaerobic bacterial metabolism, specific bacteria are selected having improved degradative abilities in environments lacking oxygen. Such bacteria may include species from the genera Geobacter, Dechloromonas, the Desulfobacteriaceae family, and other species known in the art as effective in anaerobic environments.

[0013] The microbial cleaning solution may be located into a submersion tank, where water is added to fill the tank to a desired capacity. The tank must include a plurality of rigid walls and must be watertight to maintain liquid materials within the tank. Openings may be formed in the tank above a water line for the entry and exit of items for cleaning via a conveying means. A further opening may be placed at a downward location adjacent a filter system so that submersion tank contents can continuously enter the filter system as needed. In order to improve the cleaning capacity of the system, the submersion tank may be equipped with sprayers, blowers and air knives to assist in removing organic material from parts as they both enter and exit the submersion tank via the conveyer.

[0014] The continuous cleaning system as described herein may be part of a larger automated system where parts are stamped and conveyed directly into the continuous cleaning system, and are subsequently conveyed out of the continuous cleaning system and into a post-production system for further processing. Thus, the conveyer preferably includes an in-feed conveyer, typically operated by a conveyor motor, upon which parts are located for entry into the submersion tank. This in-feed conveyer may be connected to, adjacent to, or somehow integrated with a conveying or other transport means from a stamping or other manufacturing system. Alternatively, parts may even be hand loaded on the in-feed conveyor. The in-feed conveyor preferably conveys the parts to an intermediate conveyor and/or to a submersion conveyor for conveying the parts through the submersion tank. Once the parts have travelled along the submersion conveyer so that the parts are contacted with the microbial cleaning solution, an exit conveyer may be utilized. The exit conveyer is connected to the submersion conveyer and may also be connected to, adjacent to, or somehow integrated with a conveying or other transport means for further processing of the parts post-cleaning.

[0015] As parts are conveyed through the submersion tank and contacted by the microbial cleaning solution and any sprayers, blowers or air knives within the submersion tank, debris and specifically metallic particulates are removed from the parts. This debris travels downward within the submersion tank towards a filter system adapted to collect such debris. The initial portion of the filter system may include a screen portion for collecting larger particulate matter. Any metallic debris capable of fitting though the screen portion may then alternatively be collected in a magnetic filter located adjacent the screen portion. The magnetic filter includes a sleeve and one or more magnets located within. Both the screen portion and magnetic filter may be easily removed on a temporary basis to discard any debris collected. The filter system preferably includes a pump and/or pressurizing means for increasing the flow of material from the submersion tank into and through the filter system. The filter system may also include various cartridge filters, bags filters, or other filter formats to successfully prevent particulate matter from entering the digester system.

[0016] Upon passing through the one or more filters for removing particulates, the filtered liquid passes into a digester which temporarily stores the filtered liquid and is adapted for microbe metabolism. In the event that the selected microbes are aerobic microbes (which may be preferred for their improved ability to degrade aromatic hydrocarbons), the digester is designed to maximize exposure of the microbes to oxygen. As an example, the surface area within the digester can be formed as a multi-tiered structure, whereby each tier can contain a pre-determined maximum volume of microbial matter (e.g., filtered liquid) and any additional microbial matter will travel downward to a lower tier. The multi-tiered system will maximize oxidation of the microbial matter thereby improving the rate and level of hydrocarbon metabolism by the microbes.

[0017] The tiers may be stacked and placed at an angle in a non-parallel relationship with adjacent tiers. As a result, the microbial matter may enter the digester and travel along a first or top tier, which is placed at a downward angle relative to the perpendicular axis of the digester. A second tier may be located below the first tier so that the microbial matter travels along the first tier and downward onto the second tier. The second tier is located at an opposing downward angle as compared to the downward angle of the first tier. Subsequent tiers are located below each preceding tier and at opposing downward angles. The number of tiers may vary but may include at least two tiers, at least five tiers, or even at least seven tiers. As the number of tiers increases, the exposure time of the microbial matter to oxygen increases as well. It may thus be beneficial to increase or decrease the number of tiers based upon the metabolic rates of the microbial matter. As an example, if the microbial matter travels through the digester and only a portion of the hydrocarbon material is metabolized, additional tiers may be added to improve oxidation and the resulting metabolic efficacy of the microbial matter. [0018] In addition to an increase in the number of tiers, the system may include a series of interconnected digesters, which may include two, three, or more digesters. The microbial matter may travel through each digester to increase oxidation opportunity. Alternatively, after travelling through the one or more filters located below the cleaning tank, the microbial matter may be directed into the digester having sufficient space for new microbial matter, and thus each microbe may travel through only one digester.

[0019] The digester includes a variety of internal conditions and processes to increase microbial oxidation and metabolism within the digester. It is believed that the temperature within the digester should achieve specific raised levels to improve metabolism. Ideally, this temperature may be at or about room temperature to minimize energy requirements within the system. The temperature within the digester may be about -2°C or greater. The temperature within the digester may be less than about 70°C or less. The temperature within the digester is from about 20°C to about 60°C. The digester may also be adapted to contain increased levels of oxygen as compared to ambient air located external of the digester, which is believed to increase oxidation levels of the microbial matter therein. The relative amount of oxygen within the digester by volume may be about 1.5mg/L or greater. The relative amount of oxygen within the digester by volume may be about 40mg/L or less.

[0020] The digester may include additional functionality to further assist in more efficient microbial metabolism to ready the microbe more quickly for it to be returned to the submersion tank. The digester or portions of the digester may be adapted for movement and/or vibration. Such movement may improve contact between the microbes and hydrocarbons and may also improve microbe access to oxygen and other nutrients that may be included within the digester. Blowers, fans, air knives or other means for improving microbe movement, oxidation and metabolism are also optionally included. These additional functionalities may also include systems to monitor and regulate the conditions within the digester. As an example, a temperature gauge is included, as is a means to increase and decrease the temperature as required. A temperature monitoring system may include a controller (or other similar controlling means) so that temperature is automatically increased or decreased to a pre-determined temperature without the need for manual adjustment. Alternatively, the temperature may be increased or decreased manually once a gauge indicates that the temperature has fallen outside of a preferred range. Additional functionalities such as oxygen content, nutrient content (e.g., nitrogen, phosphorus, etc.), vibration, and/or blowers may also include systems for monitoring and or controlling each variable. These systems may be automated or manual.

[0021] The digester may alternatively also permit for anaerobic metabolism, or a combination of both aerobic an anaerobic metabolism. Whereas the aerobic system described above utilizes oxygen as an electron acceptor, an anaerobic (or a combination aerobic- anaerobic) system may employ sulfates, nitrates, or iron as the necessary electron acceptor. A digester modified to permit for anaerobic or combination metabolism, may be free of the cascading shelf structure and may include a means for adding and monitoring the necessary electron acceptor materials to the digester for maximizing anaerobic metabolism of the hydrocarbons.

[0022] After passing through the digester system, the microbial matter may travel into a storage tank, where it can be stored until additional microbes are required in the cleaning tank. Alternatively, the microbial matter may remain within the digester until additional microbes are required in the cleaning tank.

[0023] Referring to all of the figures in general, and in particular to Fig. l , the system

10 includes a submersion tank 12 having a microbial cleaning solution 14 located therein. The submersion tank may further include a water supply 16. Any item or part located into the submersion tank for cleaning may be placed onto an in- feed conveyer 18 for moving the item into the submersion tank. One or more spray devices 20 may be located in close proximity to the conveyer so that items located on the conveyer may be sprayed to assist in removing unwanted materials - organic material, in particular. The in-feed conveyer leads to a submersion conveyer 22 which leads to an exit conveyer 24, by which any items located onto the conveyer will exit the system. The submersion tank includes a separator for separating organic material from water, as the organic material is removed from items located into the submersion tank. Such a separator may be an oil/water separator 26 or any other known or appropriate separator means.

[0024] The contents of the submersion tank are regulated with a plurality of monitors and communication devices. These may include a biosensor 28 for monitoring the level of microbial solution and/or activity (i.e., microbes) within the submersion tank to determine if additional microbial solution should be added to the submersion tank. A level meter 30 monitors microbe supply and water supply within the submersion tank. A pH meter monitors 32 the pH level of the water within the submersion tank, so that pH level can be closely regulated to maximize microbial cleaning effectiveness and/or metabolism. In a system relying on aerobic microbial metabolism, an oxygen meter 34 monitors the amount of oxygen in the materials within the tank. Again, as with pH level, oxygen (0 ₂ ) levels are closely monitored and modified so that microbial metabolism is improved and/or maximized. A turbidity meter 36 assists in monitoring the amount of suspended solids within the submersion tank. Over time, debris from the items located into the submersion tank for cleaning may reduce the efficacy of the microbial cleaning solution, requiring the addition of more microbial cleaning solution or steps to remove or filter the debris from the submersion tank. Efficacy of the microbial cleaning solution may also be temperature dependent and thus a thermometer 38 is included to monitor the temperature of the materials within the submersion tank and to notify any temperature control mechanism to increase or decrease temperature as needed. Each monitor, control, controller, or communication means may include a power source and central processing unit 40 as necessary to effectively identify a condition within the submersion tank and communicate that condition so that adjustments are made either automatically or manually by a control system.

[0025] The submersion tank includes a filter system 42 for continuous removal of debris and microbial fluid from within the submersion tank. The filter includes one or more screens 44 and magnetic filters 46 for removing the debris from the microbial fluid, so that the microbial fluid can pass into the digester 48 (as shown in Fig. 2), without the encumbrance of debris. As further shown in Fig. 2, the digester includes a plurality of angled surfaces or platforms 50 over which recovered microbial fluid flows to promote microbial metabolism. To further improve microbial metabolism within the digester, additional functionalities such as aerators, air nozzles, heaters, biosensors and thermometers may be included within the digester and coupled to a control system for optimizing, improving and/or maximizing the recovery of the microbe. After travelling through the digester the microbes flow into a lower tank portion 52 of the digester prior to transfer from the digester to the storage tank 54 (as shown in Fig. 3).

[0026] As further shown in Fig. 3, the storage tank 54 contains recovered microbes 56 which may be fed into the submersion tank 12 as necessary or appropriate. In addition, a virgin microbe source 58 may add new microbial cleaning solution to the submersion tank as opposed to recovered microbial cleaning solution from the digester storage tank 54. The ability of the microbes to effectively metabolize the organic material may decrease over time, thus requiring the addition of virgin microbes to improve the overall metabolic efficacy of the system. A water source 16 is also available as needed to sufficiently fill the submersion tank. Fig. 3 depicts a general schematic of material flow through the system taught herein. Material flows into the submersion tank 12 and downward through the filter system 42, where unwanted debris is collected. The remaining material flows through the filter system and into one or more digesters 48. Digested and recovered microbial cleaning solution is then transported to a storage tank 54 where it can be held until transferred into the submersion tank. Each component described herein may be controlled by individual central processing units and/or a central processing unit for the system 58.

[0027] Any numerical values recited herein or in the figures are intended to include all values from the lower value to the upper value in increments of one unit provided that there is a separation of at least 2 units between any lower value and any higher value. As an example, if it is stated that the amount of a component or a value of a process variable such as, for example, temperature, pressure, time and the like is, for example, from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, it is intended that values such as 15 to 85, 22 to 68, 43 to 51 , 30 to 32 etc. are expressly enumerated in this specification. For values which are less than one, one unit is considered to be 0.0001 , 0.001 , 0.01 or 0.1 as appropriate. These are only examples of what is specifically intended and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner. As can be seen, the teaching of amounts expressed as "parts by weight" herein also contemplates the same ranges expressed in terms of percent by weight. Thus, an expression in the Detailed Description of a range in terms of at "V parts by weight of the resulting polymeric blend composition" also contemplates a teaching of ranges of same recited amount of "x" in percent by weight of the resulting polymeric blend composition."

[0028] Unless otherwise stated, all ranges include both endpoints and all numbers between the endpoints. The use of "about" or "approximately" in connection with a range applies to both ends of the range. Thus, "about 20 to 30" is intended to cover "about 20 to about 30", inclusive of at least the specified endpoints.

[0029] The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. The term "consisting essentially of to describe a combination shall include the elements, ingredients, components or steps identified, and such other elements ingredients, components or steps that do not materially affect the basic and novel characteristics of the combination. The use of the terms "comprising" or "including" to describe combinations of elements, ingredients, components or steps herein also contemplates embodiments that consist essentially of the elements, ingredients, components or steps. By use of the term "may" herein, it is intended that any described attributes that "may" be included are optional.

[0030] Plural elements, ingredients, components or steps can be provided by a single integrated element, ingredient, component or step. Alternatively, a single integrated element, ingredient, component or step might be divided into separate plural elements, ingredients, components or steps. The disclosure of "a" or "one" to describe an element, ingredient, component or step is not intended to foreclose additional elements, ingredients, components or steps.

[0031] It is understood that the above description is intended to be illustrative and not restrictive. Many embodiments as well as many applications besides the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the invention should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for all purposes. The omission in the following claims of any aspect of subject matter that is disclosed herein is not a disclaimer of such subject matter, nor should it be regarded that the inventors did not consider such subject matter to be part of the disclosed inventive subject matter.

I CLAIM: