# US 9,040,306 B2 · High-temperature furnace, use of a spinel ceramic and method for carrying out T(O)C measurements of samples > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,040,306 B2 - Document ID: US9040306B2 - Status: Granted - Kind: B2 - Application number: 14/051,639 - Filed: 2013-10-11 - Published: 2014-02-06 - Granted: 2015-05-26 - Earliest claimed: 2010-08-27 - Assignees: LANXESS Deutschland GmbH - Applicants: LANXESS Deutschland GmbH - Inventors: Christian Heuckeroth; Rudolf Kreutzer; Peter Kawulycz - Web page: https://patentgrep.com/patent/US9040306B2 ## CPC - C04B 35/80: Fibres, filaments, whiskers, platelets, or the like - C04B 35/443: Magnesium aluminate spinel - C04B 38/00: Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof (treating slag with gases or gas generating material C04B5/06 {; expanded graphite C04B35/536}) - F27D 11/02: Ohmic resistance heating - G01N 31/12: using combustion (G01N25/20 takes precedence) - C04B 2111/00431: {Refractory materials} - C04B 2235/783: Bimodal, multi-modal or multi-fractional - F27B 17/02: specially designed for laboratory use - F27D 2019/0006: {Monitoring the characteristics (composition, quantities, temperature, pressure) of at least one of the gases of the kiln atmosphere and using it as a controlling value} - F27D 2019/0012: {Monitoring the composition of the atmosphere or of one of their components} - Y10T 436/235: In an aqueous solution [e.g., TOC, etc.] - Y10T 436/25875: Gaseous sample or with change of physical state - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - 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 - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - F27B: FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract The present invention relates to a high-temperature furnace for T(O)C measurement of a sample, which has a furnace housing which bounds a vaporization space and has a sample opening for the dropwise introduction of the sample and at least one flushing opening for introduction of a flushing liquid. According to the invention, the furnace housing is lined with a spinel ceramic on an inner side facing the vaporization space. By means of the spinel ceramic, the vaporization space is lined with a material which allows particularly high temperatures within the vaporization space and thus very complete combustion and is at the same time very resistant to temperature changes. This allows cleaning with a flushing liquid at essentially the operating temperature of the vaporization space and removal of deposited salts, in particular recrystallized organic salts, from the vaporization space in the flushing liquid in dissolved or undissolved form. Aging of the high-temperature furnace by deposited salts can thereby be avoided or at least significantly retarded. ## Claims ### Claim 1 A high-temperature furnace for T(O)C measurement on a sample, the furnace comprising a furnace housing which bounds a vaporization space and has a sample opening for introducing the sample into the valorization space, wherein: the furnace housing is lined with a spinel ceramic on an inner side facing the vaporization space, and the furnace housing has at least one flushing opening configured for introduction of a flushing liquid into the vaporization space at essentially operating temperatures of the furnace. ### Claim 2 (depends on 1) The high-temperature furnace as claimed in claim 1, further comprising at least one spraying-in nozzle at the at least one flushing opening for introducing the flushing liquid as an aerosol mist, where the at least one spraying-in nozzle has an essentially horizontally oriented input direction. ### Claim 3 (depends on 1, 2) The high-temperature furnace as claimed in either claim 1 or 2, wherein the spinel ceramic comprises at least one additive selected from a group that includes plasticizers, ceramic fibers and further inorganic fillers. ### Claim 4 (depends on 1, 2) The high-temperature furnace as claimed in claim 1 or 2, wherein the spinel ceramic has a discontinuous grain size distribution. ### Claim 5 (depends on 1, 2) The high-temperature furnace as claimed in claim 1 or 2, wherein the spinel ceramic has pores having a size less than 10 μm. ### Claim 6 (depends on 1, 2) The high-temperature furnace as claimed in claim 1 or 2, wherein the spinel ceramic has an open porosity in the range from ≧10% by volume to ≦30% by volume. ### Claim 7 (depends on 1) The high-temperature furnace as claimed in claim 1, wherein the spinel ceramic comprises a ceramic produced as an essentially isostatically pressed shaped part or a ceramic produced by a plasma coating process. ### Claim 8 (depends on 7) The high-temperature furnace as claimed in claim 7, wherein the spinel ceramic comprises various layers having a different composition and/or grain size distribution. ### Claim 9 (depends on 1) The high-temperature furnace as claimed in claim 1, further comprising structural elements comprising three-dimensional bodies installed within the furnace housing. ### Claim 10 (depends on 1, 2) A method for lining a vaporization space of a high-temperature furnace as claimed in claim 1 or 2, the method comprising lining the vaporization space with spinel ceramic. ### Claim 11 (depends on 1) A method for carrying out T(O)C measurements on samples in a high temperature furnace as claimed in claim 1, the method comprising: heating the vaporization space to operating temperature, introducing a sample into the vaporization space, vaporizing and/or oxidizing the sample in the vaporization space, measuring the amount of CO2 formed, and introducing a flushing liquid into the vaporization space at essentially the operating temperature in order to remove inorganic salts from the sample which may have crystallized on surfaces within the vaporization space. ### Claim 12 (depends on 11) The method as claimed in claim 11, wherein introducing the flushing liquid comprises spraying the flushing liquid into the vaporization space as an aerosol mist. ### Claim 13 (depends on 11) The method as claimed in claim 11, further comprising, after removal of any inorganic salts; drying the vaporization space essentially at operating temperature and subsequently introducing a further sample for T(O)C measurement into the vaporization space. ### Claim 14 (depends on 13) The method as claimed in claim 13, wherein heating the vaporization space to operating temperature comprises heating the vaporization space to a temperature of 500° C. to 2000° C. ### Claim 15 (depends on 13) The method as claimed in claim 13, wherein heating the vaporization space to operating temperature comprises heating the vaporization space to a temperature of 1200° C. to 1300° C. ### Claim 16 (depends on 11) The method as claimed in claim 11, further comprising setting the same operating temperature as a target parameter immediately after introduction of the sample and immediately after introduction of the flushing liquid. ### Claim 17 (depends on 1) The high-temperature furnace according to claim 1, wherein the at least one flushing opening is configured for receiving an injection device for introduction of the flushing liquid into the vaporization space. ### Claim 18 A high-temperature furnace for T(O)C measurement on a sample, the furnace comprising: a furnace housing defining a vaporization space, and comprising a spinel ceramic lining on an inner side of the housing facing the vaporization space; a sample opening for introducing a sample into the vaporization space; at least one flushing opening for introducing a flushing liquid into the vaporization space; and at least one spray nozzle disposed at at least one flushing opening for introducing an aerosol mist of the flushing liquid into the vaporization space. ### Claim 19 (depends on 18) The furnace according to claim 18, wherein the at least one spray nozzle has an essentially horizontally oriented input direction.