Process for removing arsenic from water
October 17, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3171735 3436177 Wastewater treatment Recovery of copper from arsenic containing metallurgical waste materials Process for removing arsenic from aqueous mediums Process for the treatment of raw materials containing arsenic and metal Process for the recovery of arsenic as a zinc arsenate and its _utilization in the purification of zinc plant electrolytes Process for recovering metal values from materials containing arsenic Process for recovering arsenic compounds by sodium hydroxide leaching Membrane processes for metal recovery and pollution control in metal process industries InventorsAssigneeApplicationNo. 778568 filed on 10/17/1991US Classes:210/652, Hyperfiltration (e.g., reverse osmosis, etc.)210/650, Filtering through membrane (e.g., ultrafiltration)210/651, Removing specified material210/661By passing through suspended bedExaminersPrimary: Dawson, Robert A.Assistant: Fortuna, Ana Attorney, Agent or FirmInternational ClassB01D 061/00AbstractA process for treating arsenic-containing aqueous waste is described wherein the aqueous waste, treated if necessary to minimize the presence of materials which reduce the efficiency of reverse osmosis membranes, is passed through an ultrafilter to remove solids followed by a chemical treatment to adjust the pH to range from about 6 to 8 and to add antiscalants and antifouling materials, then following to subject the chemically treated filtrate to a reverse osmosis process to result in a permeate stream having less than about 50 parts per billion arsenic.Field of SearchFiltering through membrane (e.g., ultrafiltration)Removing specified material Hyperfiltration (e.g., reverse osmosis, etc.) Heavy metal Including oxidation Utilizing plural diverse membranes Including ion exchange or other chemical reaction Removing ions Heavy metal Chemical treatment Centrifugally extracting Group VA metal or arsenic (Sb, Bi, or As) | |
