AU2012101019A4 - Cooling system for refractory-lined furnaces and/or gasifiers - Google Patents

Abstract

2GHK 021 AU 14 Abstract Cooling system for refractory-lined furnaces and/or gasifiers 5 The application provides a method of regulating the material temperature of refractory in a refractory lined furnace which has a hot face exposed to high temperatures during operation of refractory-lined furnace. The method has the steps of (a) installing a multiplicity of conduit devices each having a gas passageway and each made of a first refractory material having first determined thermal conductivity, disposed within refractory of 10 refractory-lined furnace made of a second refractory material having second determined thermal conductivity; (b) circulating a cooled coolant gas throughout each gas passageway of each of multiplicity of conduit devices so as to cause heat transfer of heat flux exposed to hot face of second refractory material to cooled coolant gas to form heated coolant gas; and 15 (c) cooling heated coolant gas of step (b) to derive cooled coolant gas so as to re-circulate cooled coolant gas throughout each gas passageway of each of multiplicity of conduit devices, wherein refractory-lined furnace is deployed for use in metallurgical processes for metal refining, smelting or deployed for use in gasification processes for generating product syngas to be utilized subsequently for power generation, hydrocarbon synthesis, anhydrous ammonia synthesis, methanol 20 synthesis, or a combination thereof, and cooled coolant gas is selected from air, steam, carbon dioxide, nitrogen, hydrogen, or a combination thereof. (Fig. 1)

Description

2GHi1K 021 AU_. Cooling system for refractory-lined furnaces and/or gasifiers FIELD OF THE INVENTION 5 This invention relates to a cooling system for refractory-lined furnaces and/or gasifiers, examples of such refractory-lined furnaces are cupolas, electric arc melting furnaces, induction melting furnaces, gasification furnaces and metallurgical refining furnaces, having a multiplicity of conduit passageway is installed within the body of the refractory material of the refractory-lined furnace and a coolant gas is passed through said multiplicity of conduit passageway thereby regulating the temperature of the hot 10 face side of the refractory material, the heated coolant gas is subsequently passed into a forced air heat exchanger unit or water-cooled heat exchanger unit or a combination thereof. DESCRIPTION OF THE RELATED ART 15 The primary function of the refractory material is to resist high temperature metal, slag, and combustion and or product gases, the refractory is also called upon to resist abrasion and thermal shock. The refractory requirements in such furnaces described above are among the most severe encountered and it is usually necessary to repair the lining or replace portions of it after a specified hours of operation. 20 Erosion and destruction of refractory linings will occur and it has been found that the rate of erosion and destruction of the lining increases as the temperature of the hot face of the lining (that is, the face of the lining exposed to the interior of the furnace) increases. 25 One construction proposed for use in decreasing the temperature of the hot face involves the installation of a water-cooling circuit in the refractory lining. As water flows through the cooling circuit, it extracts heat from the refractory lining and acts to decrease the temperature of the hot face of the lining. Although such constructions operate to satisfactorily reduce the temperature of the lining, they involve the use of cooling water circuits within the lining. Any leakage of water from the cooling 30 circuit has the potential to seep into the furnace and cause explosions and hydration of the refractory. This is obviously an extremely hazardous situation and it is now believed that internal water-cooling of refractory linings should be avoided. Gasification technology has, for example, been actually utilized in a power plant integrated with coal 2GHK 021 AU 2 gasification units, etc, with being oxygen or highly oxygen-enriched air is supplied to a coal gasification plant as a gasifying agent. However, consumption of the generated electric power in an auxiliary facility including an oxygen plant for producing such a gasifying agent is highly energy intensive. 5 The gasification reaction typically involves delivering feed, free-oxygen-containing gas and any other materials to a gasification reactor which is also referred to as a "partial oxidation gasifier reactor" or simply a "reactor" or "gasifier." Because of the high temperatures utilized, the gasifier is lined with a refractory material designed to withstand the reaction temperature. The feed and oxygen are intimately 10 mixed and reacted in the gasifier to form syngas. While the reaction will occur over a wide range of temperatures, the reaction temperature which is utilized must be high enough to melt any metals which may be in the feed. If the temperature is not high enough, the outlet of the reactor may become blocked with unmelted metals. On the other hand, the temperature must be low enough so that the refractory materials lining the reactor are not damaged. 15 Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as "about," is not limited to the precise value specified. In some instances, the approximating language may 20 correspond to the precision of an instrument for measuring the value. In some instances, the term about can denote a value within a range of ±10% of the quoted value. The indefinite articles "a" and "an" as used herein mean one or more when applied to any feature in embodiments of the present invention described in the specification and claims. The use of "a" and 25 "an" does not limit the meaning to a single feature unless such a limit is specifically stated. The definite article "the" preceding singular or plural nouns or noun phrases denotes a particular specified feature or particular specified features and may have a singular or plural connotation depending upon the context in which it is used. The adjective "any" means one, some, or all indiscriminately of whatever quantity. The term "and/or" placed between a first entity and a second entity means one of (1) the first entity, (2) 30 the second entity, and (3) the first entity and the second entity. Terms "heating value," "calorific value," and "caloric value" are interchangeably used within this description.

2(GHK 021 AU3 Feed, as used herein throughout the specification and claims, may refer to coal, biomass, municipal solid waste, refuse-derived fuel (RDF), industrial waste, sewage, raw sewage, peat, scrap rubber, shale ore, tar sands, crude oil, natural gas, low-BTU blast furnace off-gas, flue gas exhaust (flue gas generated from the combustion of fossil fuel in a fossil fuel boiler, or flue gas generated from the 5 combustion of a internal combustion engine unit, or a combination thereof), or a combination thereof, this is applicable for instances where the present invention is utilized as a gasification system, and in some other applications such as metallurgical smelting of metals, melting, heating or alloying of metals, feed may additionally refer to metal material, coal, flux agents such as CaO powder, or a combination of the feeds described and used for the gasification system previously described. 10 Refuse-derived fuel (RDF), which is generally produced by shredding municipal solid waste, consists largely of organic components of municipal waste such as plastics and biodegradable waste. Non combustible materials such as glass and metals are removed mechanically and the resultant material compressed into pellets, bricks, or logs and used for conversion to combustible gas, which can itself be 15 used for electricity generation or the like. Coal refers to a common fossil fuel, the most common classification is based on the calorific value and composition of the coal. Coal is of importance as a fuel for power generation now and in the future since there are a lot of coal reserves, and the coal reserves are hardly unevenly distributed over the 20 world. ASTM (American Society for Testing and Materials) standard D388 classifies the coals by rank. This is based on properties such as fixed carbon content, volatile matter content, calorific value and agglomerating character. Broadly, the coals can be categorized as "high rank coal" and "low rank coal," 25 which denote high-heating-value, lower ash content and lower heating value, higher ash content coals, respectively. Low-rank coals include lignite and sub-bituminous coals. These coals have lower energy content and higher moisture levels. 30 High-rank coals, including bituminous and anthracite coals, contain more carbon than lower-rank coals and correspondingly have a much higher energy content. Some coals with intermediate properties may be termed as "medium rank coal." The term biomass covers a broad range of materials that offer themselves as fuels or raw materials and are characterized by the fact that they are derived from 2W1K A2 A 4 recently living organisms (plants and animals). This definition clearly excludes traditional fossil fuels, since although they are also derived from plant (coal) or animal (oil and gas) life, it has taken millions of years to convert them to their current form. 5 Thus the term biomass includes feeds derived from material such as wood, woodchips, sawdust, bark, seeds, straw, grass, and the like, from naturally occurring plants or purpose grown energy crops. It includes agricultural and forestry wastes. Agricultural residue and energy crops may further include husks such as rice husk, coffee husk etc., maize, corn stover, oilseeds, cellulosic fibers like coconut, 10 jute, and the like. Agricultural residue also includes material obtained from agro-processing industries such as deoiled residue, gums from oil processing industry, bagasse from sugar processing industry, cotton gin trash and the like. It also includes other wastes from such industries such as coconut shell, almond shell, walnut shell, sunflower shell, and the like. 15 In addition to these wastes from agro industries, biomass may also include wastes from animals and humans. In some embodiments, the biomass includes municipal waste or yard waste, sewage sludge and the like. In some other embodiments, the term biomass includes animal farming byproducts such as piggery waste or chicken litter. The term biomass may also include algae, microalgae, and the like. Thus, biomass covers a wide range of material, characterized by the fact that they are derived from 20 recently living plants and animals. All of these types of biomass contain carbon, hydrogen and oxygen, similar to many hydrocarbon fuels; thus the biomass can be used to generate energy. SUMMARY OF THE INVENTION 25 The present invention provides a refractory-lined furnace and/or gasifier with a multiplicity of tubular cooling devices installed within the body of the refractory material of refractory-lined furnace, each tubular cooling device made up of a refractory material having a specified thermal conductivity and forming a closed loop fluid circulation circuit in fluid communication with an indirect or direct evaporative type cooler unit. 30 A coolant such as water or a gas such as air is circulated within the closed loop circulation circuit and is pumped by one or more primer mover unit to cause coolant to flow through each tubular cooling device and closed loop circulation circuit so as to provide a method for heat exchange of heat flux exposed on the hot face of the refractory lining material of the refractory-lined furnace to the coolant circulating 2GHK 2, AU 5 within closed loop circulation circuit to regulate the temperature of the refractory lining material of the refractory-lined furnace. The multiplicity of tubular cooling devices may be adapted in the form of tubular refractory 5 passageways each forming a circuit for a coolant gas to flow though. Depending on the selected thermal conductivity of the refractory material deployed in the fabrication, manufacturing and installation of said multiplicity of tubular cooling devices, the amount of heat flux carried away from the refractory-lined furnace varies. 10 In one embodiment of the present invention, the multiplicity of tubular cooling devices each is adapted to be made up of a first refractory material having a first determined thermal conductivity, and the refractory that is made up of the refractory-lined furnace is of a second refractory material having a second determined thermal conductivity. Tubular cooling devices may have a cross section that is substantially circular, in one embodiment of the present invention, while in another embodiment of the 15 present invention tubular cooling devices each adapted with a refractory material has a cross section that is non-circular, and may feature a hollow, rectangular type refractory pipe for greater heat dissipation surface area. Coolant selected will depend on the maximal operating temperature of each refractory-lined furnace, 20 and in some embodiments of the present invention the coolant is a gas such as air, steam, carbon dioxide, nitrogen, or a combination thereof. For instance, a nitrogen coolant provides a favorable coolant option since relativity with contents of the refractory-lined furnace during operation is minimal, while steam as a coolant gas presents capacity for high thermal loading of heat flux to be transferred from the refractory-lined furnace hotface section. 25 Indirect or direct evaporative type cooler unit may further encompass other types of cooling systems such as a water-cooled condenser unit, a forced air evaporative cooler, or a combination thereof. DESCRIPTION OF THE DRAWINGS 30 FIG. 1 illustrates one embodiment of the present invention. FIG. 2 illustrates orientation of conduit passageway devices each adapted and installed within refractory material of refractory-lined vessel of the present invention.

2(GHK 021 AU 6 FIG. 3 illustrates the overall coolant gas flow circuit operationally connected to a heat exchanger unit. DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE PRESENT INVENTION 5 In one embodiment of the present invention, flue gas from a fossil-fuel power plant boiler is captured and directed as a feed to be supplied into a gasification system to be converted (gasified) into a product syngas stream. Additional feed such as those previously described may be admixed into the gasification system to provide adequate energy input so as to provide a desired product syngas BTU content. One 10 such gasification system is herein disclosed: Gasification reactor and refractory vessel assembly example: In one example, the gasification reactor has a refractory-lined vessel that is of a substantially cylindrical 15 geometry to hold a molten metal mass, also called a melt, and an induction coil apparatus and related supporting structure for holding the refractory-lined vessel, the induction coil apparatus in operational communication with the gasification reactor. With reference to FIG. 1, gasification reactor 10 has refractory-lined vessel 20, refractory-lined vessel 20 20 is made of a first refractory material having a determined thermal conductivity, in one embodiment, the first refractory material may have the following specification: Chemical analysis of first refractory material of refractory-lined vessel 25 Material composition "A" "B" approximate range Alumina, A1203 38 36 - 39 38.5 Silica, Si02 45 44 -47 47.5 Ferric oxide, Fe203 0.3 0.3 - 0.5 0.4 30 Titanium oxide, TiO2 1.6 1.6 - 1.8 1.6 Calcium oxide, CaO 15 14 - 15 10.9 AU2 7 In accordance to one embodiment of the present invention, the first refractory material is adapted and installed with a multiplicity of conduit passageway devices 30 having each made up of a second refractory material having the following specification: 5 A cutaway illustration is shown in FIG 2, where a part of first refractory material of refractory-lined vessel 20 of FIG 1 is shown in FIG 2, 20. One of the multiplicity of conduit passageway devices 30 is also shown. It should be noted that each of the conduit passageway devices 30 may be adapted and installed within the material body of first refractory material of refractory-lined vessel 20 in either a horizontal, vertical, diagonal orientation, or a combination thereof. 10 For instance, and with reference to FIG 2, conduit passageway device 30 may be adapted and installed within the material body of first refractory material of refractory-lined vessel 20A in a vertical orientation as depicted at 30A. 15 Chemical analysis of second refractory material of each of multiplicity of conduit passageway device Material composition "A" "B" Alumina, A1203 67 70 20 Silica, SiO2 31 28 Ferric oxide, Fe2O3 0.9 0.5 Titanium oxide, TiO2 0.6 0.4 Calcium oxide, CaO 0.3 0.2 25 As indicated, and with reference to FIG 1, FIG 2, and FIG 3, each multiplicity of conduit passageway device 30 has a hollow passageway to allow for a coolant gas 40 to flow through during operation of the gasification reactor 10, the multiplicity of conduit passageway device 30 are in fluid communication with a forced air cooler unit 50, and while in other embodiments of the present invention forced air cooler unit 50 may be adapted as a water-cooled heat exchanger unit. During 30 operation of the gasification reactor 10, coolant gas 40, which is selected from air, steam, carbon dioxide, nitrogen, hydrogen, or a combination thereof, is circulated to flow thoughout each conduit passageway device 30, as the refractory-lined vessel 20 is adapted to hold a melt (molten metal, molten metal alloy, or a combination thereof), 60, within vessel 20, the hot face of first refractory material is exposed to heat flux, by circulation of coolant gas 40 through each of the conduit passageway device 30 2GHK 021 AU 8 transfers some of the heat flux exposed on the hot face of first refractory material from first refractory material to the coolant gas 40. The gas flow circuit line is partially shown at 40A, allowing a closed loop circuit for coolant gas 40 to 5 flow through each of multiplicity of conduit passageway devices 30 each installed and adapted into the material body of refractory-lined vessel 20, and gas flow circuit line 40A further directing heated coolant gas to flow from each of multiplicity of conduit passageway devices 30 back into the forced air cooler unit 50. 10 Coolant gas 40 is subsequently directed to forced air cooler unit 50 to perform cooling of the coolant gas 40 prior to being re-circulated from the forced air cooler unit 50 back to each of the conduit passageway device 30. Depending on the rate of flow of the coolant gas 40 and thermal conductivity selected of the second refractory material made into each of conduit passageway device 30, the overall thermal resistance of the first refractory material will cause a build-up of a "frozen" layer of melt to be 15 present during operation of the gasification reactor 10. This has the effect of enhancing the operating lifespan of the first refractory material of refractory-lined vessel 20. The refractory-lined vessel 20 is further adapted with a cover lid device 70 that is operationally configured with the top of the refractory-lined vessel to be substantially gas tight, and or causing the 20 refractory-lined vessel to be substantially gas tight, the cover lid device further adapted with at least one inlet port 80 to facilitate the flow of carbonaceous material, or feed, into contact with the melt contained in the refractory-lined vessel. The inlet port 80 may be operationally configured with a tubular apparatus such as a feed lance, or said 25 feed lance and or tubular apparatus is in fluid communication with the inlet port so as to perform the facilitation, transport and flow of feed into contact with the melt that is contained within the refractory lined vessel. The inlet port 80 in another embodiment of the present invention is adapted to receive a flowstream of 30 flue gas, or flue gas exhaust (flue gas generated from the combustion product of fossil fuel in a fossil fuel boiler, or flue gas generated from the combustion product of a internal combustion engine unit, or a combination thereof), to be re-directed as feed for introduction into contact with the melt 60 during operation of gasification reactor 10.

2GHiK 021AU 9 It should be noted that in accordance to the present invention, feed includes flue gas exhaust as described above, biomass, wood, coal of all ranks, lignite, peat, oil shale (shale oil), tar sands, rubber tires, crude oil, waste oil and/or sludge, industrial waste material, raw sewage, partially treated sewage, landfill waste, or combinations thereof. Feed may further include air, oxygen, carbon dioxide, nitrogen, 5 carbon monoxide gases, or a combination thereof. Feed may be introduced into the gasifier in a slurry form, or be introduced as a dry feed stream. When the above feeds are admixed in combination, it may be described as in "MultiFeedTM" mode. 10 Further, the cover lid device 70 is operationally configured with at least one outlet port 90 that is in fluid communication with at least one tubular outlet conduit device for directing the flow of product syngas and or raw syngas evolving from the melt to either a powerplant (such as a reciprocating engine unit, a gas turbine, or a fuel cell electricity-generating system), a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic 15 reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof. It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations can be made therein without departing from the spirit or scope of this invention.

Claims (5)

1. A method of regulating the material temperature of refractory in a refractory-lined furnace which has a hot face exposed to high temperatures during operation of refractory-lined furnace having the 5 steps of (a) installing a multiplicity of conduit devices each having a gas passageway and each made of a first refractory material having first determined thermal conductivity, disposed within refractory of refractory-lined furnace made of a second refractory material having second determined thermal 10 conductivity; (b) circulating a cooled coolant gas throughout each gas passageway of each of multiplicity of conduit devices so as to cause heat transfer of heat flux exposed to hot face of second refractory material to cooled coolant gas to form heated coolant gas; and 15 (c) cooling heated coolant gas of step (b) to derive cooled coolant gas so as to re-circulate cooled coolant gas throughout each gas passageway of each of multiplicity of conduit devices, wherein refractory-lined furnace is deployed for use in metallurgical processes for metal refining, 20 smelting or deployed for use in gasification processes for generating product syngas to be utilized subsequently for power generation, hydrocarbon synthesis, anhydrous ammonia synthesis, methanol synthesis, or a combination thereof, and cooled coolant gas is selected from air, steam, carbon dioxide, nitrogen, hydrogen, or a 25 combination thereof.

2. In a gasification reactor having a melt disposed within the gasification reactor for converting a feed into product syngas by contacting feed into melt and one or more induction coil apparatus for inductively melting and/or heating melt during conversion of said feed into product syngas, the 30 gasification reactor has: a refractory-lined vessel in operational communication with said gasification reactor for holding said melt disposed within; and 2(G HK 021 A1 11 refractory-lined vessel made up of first refractory material having first determined thermal conductivity, first refractory material further installed and disposed within first refractory material body a multiplicity of conduit passageway each conduit passageway made up of a second refractory material having second determined thermal conductivity so as to provide a method for 5 regulating the temperature of first refractory material which has a hot face exposed to high temperatures during operation of gasification reactor having the steps of; (a) circulating a cooled coolant gas throughout each of multiplicity of conduit passageway so as to cause heat transfer of heat flux exposed to hot face of first refractory material to cooled coolant gas to form heated coolant gas; and 10 (b) cooling heated coolant gas of step (a) to derive cooled coolant gas so as to re-circulate cooled coolant gas throughout each of multiplicity of conduit passageway; wherein product syngas is directed to flow from refractory-lined vessel to a powerplant for electric 15 power generation and or water generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof; and 20 cooled coolant gas is selected from air, steam, carbon dioxide, nitrogen, hydrogen, or a combination thereof.

3. A method of regulating the material temperature of refractory in a refractory-lined vessel of a coreless induction furnace which has a refractory hot face exposed to high temperatures of a melt 25 disposed within refractory-lined vessel during operation of coreless induction furnace, coreless induction furnace adapted with one or more induction coil apparatus each adapted with a separate cooling conduit within, having the steps of; (a) installing a first refractory material having first thermal conductivity to form refractory-lined 30 vessel; (b) adapting a multiplicity of gas conduit passageway disposed within the body of first refractory material, wherein each multiplicity of gas conduit passageway is made up of a second refractory material having a second thermal conductivity; 2GHK 021 AU 12 (c) passing a coolant gas through multiplicity of gas conduit passageway so as to transfer heat flux exposed on the hot face of first refractory material from first refractory material to coolant gas to derive heated coolant gas; (d) circulating a coolant through one or more induction coil apparatus so as to regulate the 5 temperature of one or more induction coil during operation of coreless induction furnace; (e) directing heated coolant gas from step (c) to a heat exchanger-cooler system to reduce temperature of heated coolant gas to a determined temperature range; (f) routing coolant from step (d) to heat exchanger-cooler system of step (e); and 10 coolant gas is selected from air, steam, carbon dioxide, nitrogen, hydrogen or a combination thereof, wherein coolant of step (d) is selected from water, air, nitrogen, hydrogen or a combination thereof, and coreless induction furnace is deployed for use in metallurgical processes for metal melting, 15 alloying, refining, smelting or adapted for use in a determined gasification process for generating product syngas to be utilized subsequently for power generation and or water generation, hydrocarbon synthesis, anhydrous ammonia synthesis, methanol synthesis, or a combination thereof. 20

4. A method of performing gasification in a gasifier for generation of product syngas therefrom, gasifier adapted with a refractory-lined vessel, having the steps of; (a) melting and holding a melt in refractory-lined vessel; (b) controlling the carbon content present in the melt to within a range of between 2 to 4.5 mass 25 weight percent, or controlling the equivalent carbon content (CE) present in the melt to within a range of between 2.5 to 5.8 mass weight percent during gasification operation of gasifier; (c) injecting flue gas exhausted from a combustion boiler and/or powerplant into contact with melt during gasification operation of gasifier; and (d) regulating the refractory material temperature of refractory-lined vessel by circulating one or 30 more coolant gas flow stream within refractory material to within a determined refractory material temperature range; wherein coolant gas flow stream is selected from air, steam, carbon dioxide, nitrogen, hydrogen, or a combination thereof; and 2GH{K 021 AU 13 product syngas is directed to flow from refractory-lined vessel to a powerplant for electric power generation and or water generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to 5 chemically reform product syngas into methanol product, or a combination thereof.

5. A method of performing gasification in a gasifier for generation of product syngas therefrom, gasifier adapted with a refractory-lined vessel wherein refractory material of refractory-lined vessel is made of first refractory material having a first thermal conductivity range, refractory-lined vessel 10 further adapted to hold a molten metal melt within, first refractory material is adapted and installed within first refractory material body a multiplicity of gas flow passageway each gas flow passageway made of a second refractory material having a second thermal conductivity range, having the steps of; 15 (a) directing a feed into contact with molten metal melt to dissolve part of feed into molten metal melt and generating product syngas therefrom; (b) circulating a coolant gas through multiplicity of gas flow passageway so as to regulate the temperature of first refractory material to a determined temperature range; 20 wherein product syngas is directed to flow from refractory-lined vessel to a powerplant forelectric power generation and or water generation, a first chemical catalytic reactor to chemically reform product syngas into a determined hydrocarbon product, a second chemical catalytic reactor to chemically reform product syngas into anhydrous ammonia product, a third chemical catalytic reactor to chemically reform product syngas into methanol product, or a combination thereof. 25