초록 ▼

The present invention provides a system and method for selectively removing one or more organic and also preferably one or more inorganic contaminants from plating baths. More particularly, the invented method relates to the use of a source of energy in combination with chemical oxidants, alone or i

The present invention provides a system and method for selectively removing one or more organic and also preferably one or more inorganic contaminants from plating baths. More particularly, the invented method relates to the use of a source of energy in combination with chemical oxidants, alone or in conjunction with a catalyst to oxidize organic contaminants in the plating bath to a level such that the electroplating bath can be recovered and reused after appropriate chemical adjustment. The oxidative treatment method may be a continuous process or a batch process that is performed in a single pass and the endpoint of the oxidative process detected by a sensor. Residual organics, if desired, and chloride ions in the bath are removed from the solution by a chemisorption or physisorption treatment. Inorganic contaminants are removed from the electroplating bath by selective ion exchange resins or electrodialysis, while particulate and suspended colloidal particles are removed by filtration before the treated plating bath is recycled.

대표청구항 ▼

The present invention provides a system and method for selectively removing one or more organic and also preferably one or more inorganic contaminants from plating baths. More particularly, the invented method relates to the use of a source of energy in combination with chemical oxidants, alone or i

The present invention provides a system and method for selectively removing one or more organic and also preferably one or more inorganic contaminants from plating baths. More particularly, the invented method relates to the use of a source of energy in combination with chemical oxidants, alone or in conjunction with a catalyst to oxidize organic contaminants in the plating bath to a level such that the electroplating bath can be recovered and reused after appropriate chemical adjustment. The oxidative treatment method may be a continuous process or a batch process that is performed in a single pass and the endpoint of the oxidative process detected by a sensor. Residual organics, if desired, and chloride ions in the bath are removed from the solution by a chemisorption or physisorption treatment. Inorganic contaminants are removed from the electroplating bath by selective ion exchange resins or electrodialysis, while particulate and suspended colloidal particles are removed by filtration before the treated plating bath is recycled. ish a pressure gradient between the electrode well and an extraction well; returning some of the injected water through the middle apertures and return conduit means to ground surface; whereby the electrode and immediately surrounding soil at the ends of the electrode are cooled by the circulation of water and part of the water is heated and conveys heat by convection further into the region of soil toward the nearest extraction well; so that at least part of the region of soil is heated. 4. The method as set forth in claim 3 comprising: heating the region of soil sufficiently to vaporize contained contaminants; and withdrawing vaporized contaminants through the extraction wells. 5. A method for heating soil beneath ground surface, comprising: providing spaced apart electrode wells having electrodes penetrating the soil and defining a region of soil, to be heated, extending between the electrodes; providing vacuum extraction wells penetrating the region of soil and creating low pressure sinks; applying multi-phase alternating current to the electrodes to heat soil in the region; injecting water under pressure into the soil at the electrodes to establish a pressure gradient between the electrodes and the extraction wells, so that water that is heated electrically is forced to flow toward the low pressure sinks and thereby conveys heat by convection further into the region. 6. The method as set forth in claim 5 wherein the water is injected into the soil at the top and bottom ends of each electrode, where current density is concentrated. 7. The method as set forth in claim 6 wherein: each electrode is tubular and has openings at its top, bottom and middle, and each electrode well has means for injecting water through the top and bottom openings and means for returning water to ground surface from the middling openings; and comprising: injecting the water through the top and bottom openings; and returning part of the injected water to ground surface through the middle openings whereby the electrode is cooled by circulation of water along its exterior surface. 8. The method as set forth in claim 7 comprising: controlling the rate at which injected water is returned through the middle openings. 9. A method for the application of three-phase, power-line frequency electricity to electrodes used in heating soil, comprising: placing a plurality of temperature sensors within the soil and connecting the sensors with a computer-based electrical power controller, for measuring the temperature of the soil; routing the electricity to the electrodes through an electrical power delivery system that applies the electricity to the electrodes in a specific sequence as determined by the computer-based electrical power controller responsive to the temperature measurements; and adjusting the phase and average voltage of the electricity applied to the electrodes as determined by the computer-based electrical power controller to substantially uniformly heat the contaminated soil. 10. The method as set forth in claim 3, 4, 9, 5, 6, 7 or 8 comprising: controlling the phase of alternating current applied to individual electrodes over intervals of time to cause current to flow into less conductive portions of the region of soil. 11. The method as set forth in claim 3, 4, 9, 5, 6, 7, or 8 comprising: controlling the power applied to each electrode by varying the number of voltage cycles of the alternating current that are applied to each electrode over an interval of time. 12. The method as set forth in claim 3, 4, 9, 5, 6, 7, or 8 comprising: controlling the phase of alternating current applied to individual electrodes over intervals of time to cause current to flow into less conductive portions of the region of soil; and controlling the power applied to each electrode by varying the number of voltage cycles of the alternating current that are applied to each electrode over an interval of time. 13.