# US 2008/0185348 A1 · Methods and apparatus for treating cyanide- and/or complexing-agent-containing solutions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0185348 A1 - Document ID: US20080185348A1 - Status: Published application - Kind: A1 - Application number: 12/002,642 - Filed: 2007-12-17 - Published: 2008-08-07 - Earliest claimed: 2006-12-19 - Assignees: Wieland Dental + Technik GmbH & Co. KG, a corporation of Germany - Inventors: Gerhard Gutekunst; Waldemar Mzyk - Web page: https://patentgrep.com/patent/US20080185348A1 ## CPC - C02F 1/025: {Thermal hydrolysis} - B01J 19/1856: {placed in parallel} - B01J 19/1862: {placed in series} - B01J 2219/00006: Large-scale industrial plants - C02F 2101/14: Fluorine or fluorine-containing compounds - C02F 2101/20: Heavy metals or heavy metal compounds - C02F 2101/303: {Complexing agents} - C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS ## Abstract A method of treating an aqueous cyanide- and/or complexing-agent-containing solution, including high-temperature treating the solution in a closed reaction vessel, discharging at least a portion of the treated solution from the reaction vessel, at least partially replacing the discharged fraction with untreated solution, and subjecting the untreated solution to high-temperature treatment along with a treated-solution fraction remaining in the reaction vessel. ## Claims ### Claim 1 A method of treating an aqueous solution containing complexing-agents comprising: treating the solution in a closed reaction vessel at high-temperature; discharging at least a portion of the treated solution from the reaction vessel; at least partially replacing the discharged fraction with untreated solution; and subjecting the untreated solution to high-temperature treatment along with the treated-solution fraction remaining in the reaction vessel. ### Claim 2 (depends on 1) The method of claim 1, wherein the aqueous solution contains precious metals. ### Claim 3 (depends on 1) The method of claim 1, wherein the aqueous solution contains heavy metals. ### Claim 4 (depends on 1) The method of claim 1, further comprising: transferring the treated solution into a storage tank downstream of the reaction vessel following the high-temperature treatment; cooling the treated solution; and discharging steam and gaseous reaction products from the storage tank. ### Claim 5 (depends on 4) The method of claim 4, further comprising: feeding the steam and the gaseous reaction products, for energy recovery, to at least one heat exchanger downstream of the storage tank. ### Claim 6 (depends on 4) The method of claim 4, further comprising feeding cooled solution, for energy recovery, to at least one heat exchanger downstream of the storage tank. ### Claim 7 (depends on 1) The method of claim 1, further comprising: transferring the discharged fraction of the treated solution into a storage tank downstream of the reaction vessel; cooling the discharged fraction of the treated solution; and discharging steam and gaseous reaction products from the storage tank. ### Claim 8 (depends on 7) The method of claim 7, further comprising feeding the steam and the gaseous reaction products, for energy recovery, to at least one heat exchanger downstream of the storage tank. ### Claim 9 (depends on 7) The method of claim 7, further comprising feeding the cooled solution, for energy recovery, to at least one heat exchanger downstream of the storage tank. ### Claim 10 (depends on 1) The method of claim 1, further comprising discharging between 5% and 95% of the treated solution from the reaction vessel. ### Claim 11 (depends on 1) The method of claim 1, further comprising discharging between 25% and 75% of the treated solution from the reaction vessel. ### Claim 12 (depends on 1) The method of claim 1, wherein the high-temperature treatment takes place at a temperature between 150° C. and 300° C. ### Claim 13 (depends on 1) The method of claim 1, wherein the high-temperature treatment takes place at a temperature between 220° C. and 260° C. ### Claim 14 (depends on 1) The method of claim 1, wherein the high-temperature treatment takes place at a pressure between 5 bar and 90 bar. ### Claim 15 (depends on 1) The method of claim 1, wherein the high-temperature treatment takes place at a pressure between 30 bar and 50 bar. ### Claim 16 (depends on 1) The method of claim 1, further comprising preheating the solution to be treated to a temperature between 120° C. and 180° C. prior to entering into the reaction vessel. ### Claim 17 (depends on 16) The method of claim 16, wherein the solution to be treated is preheated by way of energy which is recovered by at least one heat exchanger downstream of the reaction vessel. ### Claim 18 (depends on 1) The method of claim 1, wherein the discharged fraction of the treated solution is fed to at least one further reaction vessel and is subjected to further high-temperature treatment. ### Claim 19 (depends on 4) The method of claim 4, wherein the discharged fraction of the treated solution is fed to at least one further reaction vessel upstream of the storage tank and is subjected to further high-temperature treatment. ### Claim 20 (depends on 7) The method of claim 7, wherein the discharged fraction of the treated solution is fed to at least one further reaction vessel upstream of the storage tank and is subjected to further high-temperature treatment. ### Claim 21 (depends on 18) The method of claim 18, wherein the discharged fraction of the treated solution, in the at least one further reaction vessel, at least partially replaces the solution which has already been treated. ### Claim 22 (depends on 1) The method of claim 1, wherein the solution in the reaction vessel is continuously mixed. ### Claim 23 (depends on 1) The method of claim 1, wherein the reaction vessel used is an autoclave. ### Claim 24 (depends on 1) The method of claim 1, wherein it is executed quasicontinuously. ### Claim 25 (depends on 18) The method according to claim 18, wherein the solution is subjected to high-temperature treatment in at least two closed reaction vessels arranged in series, some of the treated solution is discharged, following the high-temperature treatment, from each of the at least two reaction vessels, the discharged fraction is replaced by untreated solution or treated solution from the upstream reaction vessel, and the high-temperature treatment is repeated. ### Claim 26 (depends on 25) The method of claim 25, further comprising transferring the discharged fraction of the treated solution from the final reaction vessel of the series into a downstream storage tank; cooling the discharged fraction; and discharging steam and gaseous reaction products from the storage tank. ### Claim 27 (depends on 26) The method of claim 26, further comprising feeding the steam and gaseous reaction products, for energy recovery, to at least one heat exchanger downstream of the storage tank. ### Claim 28 (depends on 26) The method of claim 26, further comprising feeding the cooled solution, for energy recovery, to at least one heat exchanger downstream of the storage tank. ### Claim 29 (depends on 1) An apparatus that performs the method of claim 1, comprising at least one closed reaction vessel that carries out the high-temperature treatment, at least one storage tank downstream of the at least one reaction vessel and having an outlet for steam and gaseous reaction products, and at least one heat exchanger downstream of the at least one storage tank. ### Claim 30 (depends on 29) The apparatus of claim 29, comprising at least two closed reaction vessels, operatively connected in series. ### Claim 31 (depends on 29) The apparatus of claim 29, further comprising an ammonium-recovery installation downstream of the storage tank. ### Claim 32 (depends on 29) The apparatus of claim 29, wherein the at least one reaction vessel has a continuous-mixer. ### Claim 33 (depends on 29) The apparatus of claim 29, wherein the at least one storage tank has a continuous-mixer.