# US 8,569,191 B2 · Refractory lining for titanium ore beneficiation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,569,191 B2 - Document ID: US8569191B2 - Status: Granted - Kind: B2 - Application number: 13/318,614 - Filed: 2010-05-05 - Published: 2012-03-15 - Granted: 2013-10-29 - Earliest claimed: 2009-05-05 - Assignees: E. I. Du Pont de Nemours and Company - Applicants: John James Barnes; Dat Nguyen; Peter Hill; Jay Scott Schickling - Inventors: John James Barnes; Dat Nguyen; Peter Hill; Jay Scott Schickling - Web page: https://patentgrep.com/patent/US8569191B2 ## CPC - C22B 1/02: Roasting processes (C22B1/16 takes precedence) - C21B 13/006: {Starting from ores containing non ferrous metallic oxides} - C21B 13/105: {Rotary hearth-type furnaces} - C22B 34/1209: {by dry processes, e.g. with selective chlorination of iron or with formation of a titanium bearing slag} - F27D 1/0006: {Linings or walls formed from bricks or layers with a particular composition or specific characteristics} - F27D 1/1684: {by a special coating applied to the lining} - F27B 9/16: the charge moving in a circular or arcuate path - C22B: PRODUCTION AND REFINING OF METALS (electrolytic C25); PRETREATMENT OF RAW MATERIALS - C21B: MANUFACTURE OF IRON OR STEEL (preliminary treatment of ferrous ores or scrap C22B1/00) - F27D: DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE - F27B: FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS ## Abstract The disclosure relates to a refractory which is resistant to corrosion which degrades the refractory during titanium-ore beneficiation in a furnace, particularly a rotary hearth furnace. In particular, the disclosure relates to a layered refractory lining for a furnace, for use in a titanium ore beneficiation process wherein a titanium oxide-rich molten slag is formed, comprising: (a) a first layer comprising a major proportion of alumina and a minor proportion of zirconia; (b) a second layer comprising a resistant agent for the molten slag; wherein the second layer is between the slag and the first layer. ## Claims ### Claim 1 A layered refractory lining for a furnace, for use in a titanium ore beneficiation process wherein a titanium oxide-rich and iron oxide-rich molten slag is formed, comprising: (a) a first layer comprising alumina and zirconia having about 90 to about 99 wt. % alumina, and about 1 to about 10 wt. % zirconia, based on the entire weight of the first layer; (b) a second layer comprising a resistant agent reaction product of the molten slag and the alumina and the zirconia; wherein the second layer is between the molten slag and the first layer; and wherein the total amount of calcium oxide, magnesium oxide, yttrium oxide and cerium oxide is less than 1 wt. %, based on the total weight of the refractory body. ### Claim 2 (depends on 1) The layered refractory lining of claim 1 wherein the second layer is formed in situ during the beneficiation process. ### Claim 3 (depends on 1) The layered refractory lining of claim 1 wherein the furnace is an electric arc furnace. ### Claim 4 (depends on 1) The layered refractory lining of claim 1 wherein the furnace is a rotary hearth furnace. ### Claim 5 (depends on 1) The layered refractory lining of claim 1 wherein the alumina ranges from about 97 wt. % to about 98 wt. % based on the entire weight of the first layer. ### Claim 6 (depends on 1) The layered refractory lining of claim 1 wherein the zirconia ranges from about 1 wt. % to about 2 wt. % based on the entire weight of the first layer. ### Claim 7 (depends on 1) The layered refractory lining of claim 1 further comprising calcia or magnesia or mixtures thereof. ### Claim 8 (depends on 1) The layered refractory lining of claim 1 further comprising yttrium oxide or cerium oxide or mixtures thereof. ### Claim 9 A process for forming a resistant agent in a refractory body of a furnace for use in a titanium ore beneficiation process, comprising: (i) forming agglomerates comprising carbon-based materials and a titanium-bearing ore, the quantity of carbon of the agglomerates being sufficient for, at an elevated temperature, reducing ferric oxide to ferrous oxide and forming a slag that is comprised of titanium oxide and iron oxide; (ii) introducing the agglomerates onto a carbon bed of a moving hearth furnace, wherein the moving hearth furnace comprises a refractory lining comprising a first layer comprising alumina and zirconia having about 90 to about 99 wt. % alumina, and about 1 to about 10 wt. % zirconia, based on the entire weight of the first layer; (iii) heating the agglomerates in the moving hearth furnace to a temperature sufficient for reducing and melting the agglomerates to produce a titanium oxide-rich molten slag, which contacts the refractory lining to produce a second layer comprising a resistant agent which is a reaction product of the slag, the alumina and the zirconia; wherein the second layer is formed between the slag and the first layer; and wherein the total amount of calcium oxide, magnesium oxide, yttrium oxide and cerium oxide is less than 1 wt. %, based on the total weight of the refractory body. ### Claim 10 A resistant agent for a titanium oxide-rich molten slag comprising: a reaction product of a first layer of a refractory lining comprising alumina and zirconia having about 90 to about 99 wt. % alumina, and about 1 to about 10 wt. % zirconia, based on the entire weight of the first layer and the titanium oxide-rich molten slag, wherein the resistant agent is the reaction product of the titanium oxide of the slag and the alumina and zirconia of the first layer; and wherein the total amount of calcium oxide, magnesium oxide, yttrium oxide and cerium oxide is less than 1 wt. %, based on the total weight of the refractory body. ### Claim 11 A preformed layered refractory lining for a furnace, for use in a titanium ore beneficiation process wherein a titanium oxide-rich and iron oxide-rich molten slag is formed, comprising: (a) a first layer comprising alumina and zirconia having about 90 to about 99 wt. % alumina, and about 1 to about 10 wt. % zirconia, based on the entire weight of the first layer; and (b) a paste comprising a source of titania, a source of carbon, and a binder, wherein the first layer and the paste are heated prior to beneficiation so that paste forms a second layer attached to the first layer.