Hydrogen-based material processing equipment and processes

Abstract

A process for treating a material, such as by a calcination or reduction process, is disclosed that includes reacting hydrogen and oxygen in a reaction chamber to produce heat and steam, venting the steam from the reaction chamber, using the heat to treat the material to produce a treated material, and returning at least a portion of the steam vented from the reaction chamber to the process. An apparatus is also disclosed.

Description

Technical Field

[0001] The present invention relates to a process and an apparatus for treating materials by calcination. The present invention also relates to a process and an apparatus for treating materials via a reduction process.

Background Art

[0002] Dehydration process Materials are often processed to remove water from hydrates, etc., and / or to remove oxygen from oxides, etc.

[0003] For example, in the production of alumina (Al2O3) in an alumina production plant such as a Bayer process plant, aluminum hydroxide (Al2O3·3H2O - aluminum hydroxide, aluminum trihydrate, and also called hydrated alumina) is calcined to remove moisture. Similarly, by dehydrating gypsum (CaSO4·2H2O), anhydrous (CaSO4) is formed.

[0004] Known calcination apparatuses have a reaction chamber that burns natural gas and oxygen to form flue gas containing N2, CO2, and steam (steam) and heat. The heat generated in the reaction chamber by the combustion of natural gas and oxygen is used to calcine, i.e., dehydrate, the hydrated material to form the dehydrated material. Due to heat losses during calcination, the amount of energy provided to the reaction chamber significantly exceeds the theoretical requirements. A part of the heat generated in the reaction chamber is transferred to the steam in the flue gas. However, as a method of reducing the amount of energy required for calcination, attempting to recapture the heat of the flue gas is technically difficult and / or may be costly.

[0005] Reduction process Metal oxides such as hematite (Fe2O3) can be subjected to reducing conditions, such as smelting or other reduction processes, to reduce the metal in the metal oxide. If sufficient reduction occurs, a base metal can be formed.

[0006] Smelting and other reducing equipment often use coal as a reducing agent to form by-products containing base metals and CO2. However, as with calcination equipment, some of the heat generated in the smelting process is transferred to the flue gas. [Overview of the project] [Problems that the invention aims to solve]

[0007] Using natural gas in the calcination equipment and coal in the smelting process can generate CO2 and other harmful by-products.

[0008] The above description should not be considered to represent common knowledge in Australia or anywhere else. [Means for solving the problem]

[0009] This invention is based on the inventors' recognition that considerable advantages can be achieved by using hydrogen as a combustion fuel instead of natural gas for calcination processes, such as the process of forming alumina by calcining aluminum hydroxide or the process of forming anhydrous materials by dehydrating gypsum.

[0010] This invention is also based on the inventors' recognition that considerable advantages can be realized by using hydrogen instead of coal for reduction processes such as smelting.

[0011] The present invention provides a process for processing a material to form a processed material. This process may include a calcination (i.e., dehydration) process to form a dehydrated material, or a reduction process to form, for example, a base metal. For example, the material may be aluminum hydroxide or gypsum, and the processed material may be alumina or anhydrous alumina, respectively. For example, the material may be hematite (Fe2O3), and the processed material may be iron.

[0012] For example, the present invention provides a process for processing a material by a calcination process or a reduction process, which includes reacting hydrogen and oxygen in a reaction chamber to generate heat and steam, releasing the steam from the reaction chamber, using this heat to process the material and produce a processed material, and returning at least a portion of the steam discharged from the reaction chamber to the process, for example, the reaction chamber.

[0013] The term "reaction chamber" is understood herein to mean a chamber for a calcination reaction or a reduction reaction.

[0014] The advantage of reacting hydrogen and oxygen is that it eliminates the need to use hydrocarbon fuel sources such as natural gas for calcining materials, or coal for reduction processes such as smelting materials. This can help reduce carbon-based emissions from calcination and reduction processes.

[0015] Furthermore, this process can be operated using only oxygen as the oxygen source, thereby completely avoiding the use of air (i.e., a gas mixture containing 78% nitrogen and 21% oxygen). This is advantageous in that it reduces the volume of gas processed in the plant.

[0016] This process can be operated with oxygen-rich air, and depending on the concentration level, the amount of nitrogen can be reduced compared to when operating with air.

[0017] As described above, the process includes returning at least a portion of the vapor discharged from the reaction chamber back into the reaction chamber. This is advantageous in that it returns the vapor to the process, for example, by returning the heat retained in the vapor to the reaction chamber, thereby helping to reduce the amount of energy required to process the material. The vapor can also contribute to the fluidization and / or transport of the material and / or processed material throughout the process. The vapor discharged and transferred back into the process may be at least 30% by volume, and usually at least 40% by volume, relative to the volume of vapor discharged.

[0018] As described above, this process generates steam by reacting hydrogen and oxygen. This reaction may be carried out by the combustion of hydrogen and oxygen gases.

[0019] This reaction may also be carried out by reacting chemically bonded oxygen and hydrogen. In this specification, the term “chemically-bonded” is understood to mean elemental oxygen that is chemically bonded to a heteroatom, such as a metal. For example, an example of chemically bonded oxygen is the oxygen present in iron oxide.

[0020] Furthermore, for example, dehydration of the material can generate vapor in the reaction chamber when forming the processed material.

[0021] This process may include maintaining the vapor at a temperature above its condensation temperature under the operating conditions of the process. Typically, the condensation temperature of vapor is 100°C at atmospheric pressure. This process can be carried out at or below atmospheric pressure.

[0022] Stated another way, the process can be carried out without placing the reaction chamber under a pressure higher than the pressure resulting from operating the process as described above, i.e., by supplying hydrogen and oxygen to the reaction chamber, combusting the hydrogen and oxygen to produce steam and heat, and using this heat within the process to process materials.

[0023] More specifically, the process can be carried out without configuring the reaction chamber as a pressure vessel.

[0024] The process can include using the steam generated in the reaction chamber as a means of transport, i.e., as a fluidizing gas within the process.

[0025] The material and / or the processed material may be in particulate form. When the material and / or the processed material is in particulate form, the steam generated in the reaction chamber can be used to transport the particulate material and / or the particulate processed material into and / or out of the reaction chamber.

[0026] The process can include using the steam generated in the reaction chamber as a heat transfer medium for the process.

[0027] Another advantage of reacting hydrogen and oxygen to process materials is that it provides an opportunity to produce steam that can be beneficially used within the process and / or in the operation of a plant such as a buyer process plant, or other industrial facilities and / or other units of the components / devices of an industrial facility.

[0028] For example, a portion of the steam generated in the reaction chamber may be transferred to components including a mechanical steam recompressor, a thermal steam recompressor, a generator, and / or a heat recovery unit. Examples of generators include Kalina generators or organic Rankine cycle generators. Examples of heat recovery units include regenerators, regenerators, heat exchangers, heat wheels, economizers, and heat pumps. As an additional example, at least a portion of the steam generated in the reaction chamber may be used in processes other than calcination, such as during the digestion of bauxite or the evaporation of Bayer liquid.

[0029] Hydrogen can have a purity of over 99%.

[0030] The flue gas may be up to 100% steam.

[0031] The material may be a hydrate and may be treated to form a treated material which is a dehydrated form of the hydrate.

[0032] This process may be a calcination process for dehydrating the material.

[0033] The material may be a metal oxide such as hematite (Fe2O3). In that case, this process may be part of a direct reduction smelting process for forming base metals such as iron.

[0034] The present invention also provides a plant for carrying out the above process.

[0035] The present invention also provides a process for starting a plant for processing a material by a calcination process or a reduction process, the plant comprising a reaction chamber in which the material is processed, the process comprising a preheating step of heating the reaction chamber until predetermined conditions, such as steady-state conditions, are achieved, and then a step of starting to supply the material to the reaction chamber.

[0036] The specified conditions may be steady-state conditions. The term “steady state conditions” is understood herein to mean that the process has completed its startup phase and is operating in or beyond a predetermined operating state within control parameters that indicate stable operation to the plant operator. The control parameters may be any appropriate control parameters selected by the plant operator, including temperature at various points in the process. An example of a control parameter is the condensation temperature of the steam or a temperature above it.

[0037] After the process reaches steady-state conditions, the process may include discharging a flue gas, which is at least 85 volume%, typically at least 90 volume%, and more typically at least 95 volume%, of vapor from the reaction chamber.

[0038] The preheating step is not limited to the combustion of hydrogen and oxygen. The preheating step may include burning any suitable fuel source, including hydrocarbon fuels, inside or outside the reaction chamber, and transferring heat to the reaction chamber.

[0039] As a specific example, an external steam source, such as steam generated in an industrial plant, can be used to heat the reaction chamber in the preheating step. The reaction chamber may be heated in the preheating step by transferring at least a portion of the generated steam into the reaction chamber.

[0040] Changing the operating conditions after steady-state conditions have been reached for the reaction of hydrogen and oxygen in the reaction chamber may include providing a gas feed that increases the proportion of hydrogen over a predetermined period of time.

[0041] The present invention also provides a process for processing a material by a calcination process or a reduction process, the process comprising burning hydrogen and oxygen to generate steam and heat, using this heat to process the material and produce a processed material, and using the steam generated from the combustion as a transport gas in the process.

[0042] The process described in the preceding paragraph may further include discharging steam from the process and then transferring at least a portion of the discharged steam back into the process.

[0043] The described process may include burning hydrogen and oxygen to generate vapor and heat in a reaction chamber, and processing materials in the reaction chamber.

[0044] Alternatively, the process may include burning hydrogen and oxygen in one reaction chamber to generate steam and heat, transferring the steam and heat to a second reaction chamber, and processing the material in the second reaction chamber.

[0045] This process can be applied to existing calcination plants or reduction plants, such as smelting plants, which operate using natural gas as a fuel source and air as an oxygen source for combustion of the fuel source.

[0046] Existing plants may be appropriately modified to use hydrogen as a fuel source and oxygen (usually oxygen alone) as an oxygen source for reactions such as the combustion of the fuel source.

[0047] Furthermore, existing plants may be modified so that at least some of the steam discharged from the reaction chamber is transferred back into the reaction chamber and functions as a transport gas and, optionally, as a heat transfer medium.

[0048] This invention also provides the following: An apparatus for processing materials, The device is A reaction chamber configured for processing materials; A hydrogen source capable of reacting with oxygen in this reaction chamber, for processing materials in the reaction chamber and producing a flue gas containing the processed materials and vapors; The exit for processed materials; Flue gas outlet; and A line for supplying at least a portion of the flue gas discharged through the flue gas outlet to the device. A device that includes this.

[0049] This apparatus may include lines for supplying at least a portion of the flue gas discharged through the flue gas outlet to a component other than the reaction chamber.

[0050] The apparatus may include a first reaction chamber for processing materials and burning hydrogen and oxygen, and a second reaction chamber for generating heat for use in the second reaction chamber.

[0051] The option of two reaction chambers may be advantageous depending on whether the processing process of the present invention is to be incorporated into an existing processing plant.

[0052] In that case, the existing reaction chamber can continue to function as a chamber for processing materials, and a second reaction chamber can be constructed specifically for burning hydrogen and oxygen, located in close proximity to the existing plant, and operationally connected to supply heat to the existing reaction chamber.

[0053] The present invention also provides a plant for processing materials, the plant including the above-mentioned apparatus for processing materials. [Brief explanation of the drawing]

[0054] Embodiments of the present invention will be further described with reference to the following non-limiting drawings.

[0055] [Figure 1]Figure 1 illustrates one embodiment of an apparatus for processing materials according to the present invention. [Figure 2] Figure 2 illustrates another embodiment of the apparatus for processing materials according to the present invention. [Figure 3] Figure 3 illustrates another embodiment of the apparatus for processing materials according to the present invention, although it is not the only one. [Figure 4] Figure 4 illustrates one embodiment of a processing plant according to the present invention, based on an embodiment of the apparatus for processing materials according to the present invention shown in Figure 3. [Figure 5] Figure 5 shows the XRD results generated during a test operation related to the calcination of gibbsite in a steam environment according to the present invention. [Modes for carrying out the invention]

[0056] Figure 1 shows one embodiment of an apparatus for processing materials. In Figure 1, the apparatus 23 includes a reaction chamber 25 for processing the material.

[0057] The reaction chamber 25 can be any suitable chamber. For example, the reaction chamber 25 may include a rotary kiln, a hydrogen reduction vessel, or a gas suspension or calcination chamber. The process of the present invention does not need to be operated under high pressure conditions, and therefore the reaction chamber 25 does not need to be a pressure vessel.

[0058] The reaction chamber 25 is in fluid communication with a hydrogen source 27, an oxygen source 29 (oxygen only in this embodiment), and a material source 31. The material source 31 contains the material to be processed. The reaction chamber 25 includes an inlet and a transfer line for supplying these feed materials to the reaction chamber 25. The reaction chamber 25 includes a processed material discharge line 33 for discharging the processed material formed in the reaction chamber 25. The reaction chamber 25 also includes an outlet line 35 for discharging the flue gas generated in the reaction chamber 25.

[0059] Hydrogen and oxygen from the hydrogen source 27 and oxygen source 29 are supplied to the reaction chamber 25, respectively, and subjected to a reaction, for example, combustion, to generate heat and flue gas. The flue gas, including steam, is discharged from the reaction chamber 25 via the flue gas line 35.

[0060] Heat is used to process materials.

[0061] If the material contains bound water such as hydrates, processing the material involves removing the water from the material to form hydrates and steam, respectively. For example, aluminum hydroxide (Al(OH)3), gypsum (CaSO4·2H2O), calcite (CaCO3), and hydrated coal can be processed using the heat generated in reaction chamber 25 to form alumina (Al2O3), anhydrous gypsum (CaSO4), lime (CaO), and dehydrated coal, respectively.

[0062] When the fuel source is not limited to hydrogen but includes other fuels such as natural gas (as in some embodiments of the present invention), the flue gas stream will contain other components such as CO2 in addition to steam. However, when hydrogen is the sole fuel source and is subjected to a reaction with only oxygen in the reaction chamber 25, for example, for combustion, steam is the only component in the flue gas line 35. It should be understood that the flue gas may contain impurities such as particulate matter and other trace flue gas components, but otherwise it will have a high purity of over 99%. The generation of steam only means that there is no need to separate other flue gas components such as CO2 and N2 before reusing the steam. Separating flue gas into its individual components is technically difficult, and attempting to separate steam from flue gas is often costly.

[0063] In one embodiment, the hydrogen source 27 has a purity of over 99%.

[0064] When apparatus 23 is used to dehydrate or remove water from a material, the water expelled from the material is also present in the flue gas line 35. Thus, apparatus 23 has two steam sources: the first source is from the reaction of hydrogen and oxygen, and the second source is from the dehydration of the material (i.e., hydrate).

[0065] In some embodiments, oxygen is supplied in a stoichiometric excess relative to hydrogen to ensure complete combustion of hydrogen.

[0066] If oxygen is supplied in a stoichiometric excess, the flue gas in flue gas supply line 35 may contain trace amounts of oxygen (e.g., less than 5%). Generally, the excess oxygen used in the combustion of hydrogen is kept to a minimum.

[0067] When using hydrogen to reduce a material in the form of hematite (Fe2O3) or another metal oxide, the reaction typically requires an excess of hydrogen; that is, enough hydrogen to provide the temperature necessary for the reaction to proceed, and then enough hydrogen to subsequently reduce the hematite or other metal oxide.

[0068] For example, it should be noted that the reduction of hematite can also result in various oxidation products of varying degrees, not just iron. Therefore, the product may contain FeO.

[0069] As described above, by using only hydrogen and oxygen in the reaction to generate heat for the reaction chamber 25, the apparatus 23 does not produce CO2 or other carbon-based emissions.

[0070] If hydrogen is supplied from renewable resources, the device 23 can significantly reduce its carbon footprint compared to a device that relies on hydrocarbon fuels.

[0071] In the embodiment shown in Figure 1, the flue gas line 35 includes a flue gas transfer line 37 that is in fluid contact with the reaction chamber 25. The flue gas transfer line 37 transfers at least a portion of the flue gas (typically at least substantially vapor) in the flue gas line 35 to the reaction chamber 25. If the heat in the flue gas is not captured and instead released into the environment, up to 30% of the heat generated in the reaction chamber 25 is lost to the environment. The advantage of returning at least a portion of the vapor to the reaction chamber 25 via the flue gas line 35 is that the heat that would otherwise be lost to the environment by venting the vapor is returned to the reaction chamber 25. The vapor can thus function as a heat transfer medium, as the heat from the vapor can be used elsewhere in the apparatus 23. Returning the vapor to the reaction chamber 25 using the flue gas transfer line 37 can also help reduce the amount of hydrogen required to maintain the reaction temperature in the reaction chamber 25, as the vapor contributes to the heat in the reaction chamber 25.

[0072] It should be noted that, in some situations, depending on the reaction conditions in the reaction chamber 25, small amounts of solids may be present in the flue gas (i.e., vapor) even after it has passed through a solid filtration unit such as a bag house and / or electrostatic precipitator. If small amounts of solids are present in the flue gas, an additional filtration step can be performed to remove the solids before returning at least a portion of the vapor to the reaction chamber 25 via the flue gas transfer line 37.

[0073] To prevent steam condensation in the flue gas line 35 and the flue gas transfer line 37, lines 35 and 37 are maintained at temperatures above the steam condensation temperature. In one embodiment, the steam condensation temperature is 100°C. In one embodiment, the steam in the flue gas line 35 is superheated steam, i.e., above 100°C. In one embodiment, the steam temperature is maintained above 160°C. Maintaining the steam temperature above 100°C (e.g., about 160°C) can help prevent steam condensation. Preventing steam condensation can also help reduce the generation of condensed steam that would cause materials and / or processed materials to “stick” to the walls and surfaces of the reaction chamber 25 and the surrounding structure. Preventing steam condensation in the flue gas line 35 helps prevent the steam density from falling below a threshold that would prevent the steam in line 35 from acting as a fluid flowing medium such as a transport gas. Since the latent heat required to break up steam (dissolve water into steam) uses a considerable amount of energy, maintaining the temperature of apparatus 10 above the steam condensation temperature may help reduce or eliminate the energy-intensive steam heating step.

[0074] The condensation temperature of the vapor depends on the pressure in the flue gas line 35. Generally, as the pressure in the flue gas line 35 increases, the temperature at which the vapor condenses also increases. As described above, in one embodiment, the apparatus 10 is operated at atmospheric pressure, such as approximately 1 atmosphere.

[0075] Figure 2 shows another embodiment of the apparatus for processing the material. Apparatus 23a in Figure 2 is similar to apparatus 23, and the same reference number is used to describe similar features.

[0076] Further embodiments of the apparatus are shown in Figure 2. Apparatus 23a in Figure 2 is similar to apparatus 23 in Figure 1, and the same reference numeral is used to describe similar features.

[0077] As shown in Figure 2, apparatus 23a has a hydrogen source 27 and an oxygen source 29 similar to apparatus 23, but uses material source 31a instead of material source 31 in Figure 1. Thus, in apparatus 23a, oxygen and hydrogen are burned in the reaction chamber 25 to produce heat and vapor, whereas material source 31a contains a material with chemically bonded oxygen. Hydrogen reduces the material, and the heat produced by the combustion of hydrogen and oxygen can be used to accelerate the reduction of the material. In such embodiments, the combustion of hydrogen and oxygen may occur before introducing material source 23a into the reaction chamber 25 to minimize or eliminate any contact between oxygen and the material. This may help reduce or eliminate the occurrence of oxidation by oxygen of the material and / or the processed material. Hydrogen is also usually present in stoichiometric excess relative to oxygen from oxygen source 29 and would help ensure that all oxygen is consumed before the reduction of the material.

[0078] As an example, material source 31a may be iron oxide such as magnetite (Fe3O4) and hematite (Fe2O3). Oxygen in the iron oxide can react with hydrogen in the reaction chamber 25 to form water and reduced forms of iron oxide. The reduced form of iron depends on the reaction conditions and the stoichiometric ratio of the metal oxide to hydrogen. For example, Fe2O3 can be reduced to Fe3O4. Further reduction can be used to obtain FeO, and finally Fe 0 This can form [a specific compound]. The degree of reduction is determined by the reaction conditions and the stoichiometric ratio of the reactants. Although iron oxide is described as the material source 31a, apparatus 23a is not limited to the reduction of iron, and other metal oxides can be treated (i.e., reduced) in apparatus 23a.

[0079] The advantages of transferring at least a portion of the flue gas (i.e., vapor) from the flue gas line 35 to the reaction chamber 25 via the flue gas transfer line 37 in apparatus 23 also apply to apparatus 23a.

[0080] In the embodiments shown in Figures 1 and 2, the material / processed material flow is countercurrent to the flue gas flow. However, in some embodiments, the material / processed material and flue gas flows are cocurrent. Countercurrent may be useful when the apparatus 23 is used to dewater the material.

[0081] Figure 3 shows an example of the apparatus 100 used to process the material. Apparatus 100 is similar to apparatus 23 in the embodiment of Figure 1. In this regard, apparatus 100 includes, like apparatus 23, a reaction chamber 112, a hydrogen source 114, an oxygen source 115, a material source 116, a discharge line for the processed material 117, a flue gas discharge line 118, and a flue gas transfer line 120. However, apparatus 100 can be modified, for example, by removing the oxygen source 115 and / or replacing the material source 116 with a material source having chemically bonded oxygen, similar to apparatus 23a or 23b.

[0082] In the embodiment shown in Figure 3, the material is supplied from the material source 116 to the reaction chamber 112 via a dryer 124. The dryer 124 removes at least some of the surface-bound water from the material, forming at least some dried material upstream of the reaction chamber 112. The dryer 124 is typically used when the apparatus 100 is used to dehydrate the material. For example, if the material is aluminum hydroxide or gypsum, the dryer 124 can remove all of the surface-bound water. It should be noted that the dryer 124 is not required in all embodiments. If used, after being transferred to the dryer 124, the material is then processed in the reaction chamber 112. For example, the reaction chamber may function as a calcination apparatus, and the processing of the material is carried out by calcination.

[0083] In the embodiment shown in Figure 3, for example, after calcination in the reaction chamber 112 where the processed material is formed, the processed material is then transferred to a heat recovery device 128 that recovers heat from the processed material. The heat recovery device 128 can be any suitable form of device. This heat recovery helps to cool the processed material, form a cooled processed material, and retain heat within the device 100. The discharge line 117 for the processed material supplies the cooled processed material for further processing such as packaging and shipping.

[0084] In the embodiment shown in Figure 3, the dust collection device 126, such as a baghouse, is in fluid communication with the dryer 124. The flue gas line 118 extends from the dust collection device 126.

[0085] In the embodiment shown in Figure 3, the flue gas transfer line 120 is in fluid communication with the flue gas line 118 and the heat recovery unit 128. At least a portion of the steam in the flue gas flow 118 is transferred to the heat recovery unit 128 via the flue gas transfer line 120. The steam transferred to the heat recovery unit 128 is used as a transport gas or fluid medium to help transfer the material and / or processed material via the device 100.

[0086] The steam passed through the heat recovery unit 128 moves to the reaction chamber 112, the dryer 126 (if used), and then through the dust recovery unit 126. The direction of this steam movement is indicated by arrow 132. When the material is introduced into the dryer 124 and / or enters the reaction chamber 112, dust and other particulate matter are carried by the steam and transferred to the dust recovery unit 126.

[0087] Since the materials and processed materials generally move in the opposite direction to the steam flow (i.e., opposite to the direction of steam movement 132) through the heat recovery unit 128, reaction chamber 112, and dryer 126, the net flow of materials and processed materials through the apparatus 100 is generally countercurrent to the steam flow. Note that while there may be localized parallel flow of materials and / or processed materials and steam within the dryer 124, reaction chamber 112, and heat recovery unit 128, overall, a net countercurrent flow of materials and / or processed materials may occur.

[0088] The flue gas line 118 is divided into two lines. The first line is the flue gas transfer line 120 that supplies steam to the heat recovery unit 128. The second line supplies steam as a steam source 130 for use outside the unit 100.

[0089] The steam source 130 may be used to supply steam to other devices / components (one or more) within a plant / facility such as an industrial plant / facility.

[0090] For example, if the plant is a bauxite processing plant / facility such as a Bayer process plant, the steam source may be used by a device / component(s) encompassing a digester during the digestion of bauxite, the evaporation of spent Bayer liquid, and causticization to remove impurities in the boiler / steam generator that captures the Bayer process and low-pressure steam. In this way, device 100 can be used as a steam generator. The dashed line 131 extending from the steam source 130 indicates, in some embodiments, that the steam is not stored or discharged but is instead used elsewhere by the device / component. The steam in the steam source 130 can be used continuously by the device / component.

[0091] In some embodiments, the apparatus / component is a recompressor, such as a mechanical steam recompressor and / or a thermal steam recompressor, for “upgrading” the steam source 130 to a higher pressure. For example, a mechanical steam recompressor can upgrade the steam from 1 atmosphere to 5 atmospheres, and a thermal steam recompressor can upgrade the steam from 5 atmospheres to over 10 atmospheres.

[0092] In some embodiments, the apparatus / component is a generator or power unit, such as a Kalina system, an organic Rankine cycle system, or a turbo expander, which can convert the heat in the steam into work, such as generating electricity from the steam provided by the steam source 130.

[0093] In some embodiments, the apparatus / components are heat recovery units such as a heat recovery device, regenerator, heat exchanger thermal wheel, economizer, and heat pump, which recover heat from the steam source 130.

[0094] It should be noted that when the device / component recovers heat from the steam source 130, if sufficient heat is recovered from the steam source 130, the steam in the steam source 130 may condense, thereby forming a water supply (not shown). This water supply may be used in the plant / facility.

[0095] A control valve 134 is provided at the junction of the flue gas transfer line 120 and the steam source 130 to control the relative flow of steam in the flue gas transfer line 120 and the steam source 130. The control valve 134 can be operated manually or autonomously to control the relative flow of steam in the flue gas transfer line 120 and the steam source 130. The relative flow of steam in the flue gas transfer line 120 and the steam source 130 may be determined by the operating conditions of the apparatus 100 and, for example, the heat requirements for calcination.

[0096] In some embodiments, the above-described apparatus / components are provided upstream of the control valve 134. In such embodiments, the vapor in the flue gas is utilized by the apparatus / components before passing through the control valve 134 and entering the flue gas transfer line 120 or the vapor source 130. The vapor entering the vapor source 130 can be utilized elsewhere, as shown by the dashed line 131.

[0097] Utilizing the excess steam generated by apparatus 100 can help improve the efficiency of other apparatus / equipment located within and around the plant / facility that require the use of steam for their operation. Utilizing the excess steam can also help convert thermal energy into work.

[0098] Although the oxygen source 115 and hydrogen source 114 are shown in Figure 3 as being connected to the reaction chamber 112 and supplying these materials directly to the reaction chamber 112, it should be noted that the oxygen source 115 and hydrogen source 114 only need to be fluidly connected to the reaction chamber 112. Therefore, the oxygen source 115 and / or hydrogen source 114 may be connected upstream of the reaction chamber 112 rather than directly to the reaction chamber 112.

[0099] In Figure 3, the upstream side of the reaction chamber 112 is opposite to the direction of arrow 132, that is, it is toward the heat recovery device 128. For example, in one embodiment, the oxygen source 115 is connected to the heat recovery device 128.

[0100] In such a configuration, the oxygen transferred from the oxygen source 115 to the reaction chamber 112 via the heat recovery unit 128 can function as a cooling fluid to help cool the material processed in or near the outlet line 117. At the same time, the oxygen is heated before entering the reaction chamber 112. Similarly, the hydrogen source 114 can be connected to the heat recovery unit 128 instead of the oxygen source 115. As a further alternative, both the oxygen source 115 and the hydrogen source 114 are connected to the heat recovery unit 128.

[0101] If the oxygen source 115 and / or hydrogen source 114 are connected upstream of the reaction chamber 112, the steam from the return line 120, which is transferred to the heat recovery unit 128, is used to transfer oxygen and / or hydrogen gas to the reaction chamber 112 for combustion.

[0102] In one embodiment, the material supplied to the reaction chamber 112 via the material source 116 is in a form in which oxygen is chemically bonded to the material, as is the case with material source 31a. In such embodiments, an oxygen source 115 may not be necessary. Therefore, an oxygen source 115 is not required in all embodiments. However, in some embodiments, material source 116 provides the reaction chamber 112 with a material having chemically bonded oxygen, and oxygen source 115 also provides oxygen to the reaction chamber 112 in a manner similar to that described with reference to apparatus 23a in Figure 2.

[0103] Apparatus 23, 23a, 23b and 100 in Figures 1 to 3 are shown in exemplary form only. These are examples of more possible embodiments. It should be understood that features such as the reaction chamber 112, the heat recovery unit 128 and the dryer 126 can be formed from several different components, and the reaction chamber 112, the heat recovery unit 128 and the dryer 126 can have different stages. For example, the reaction chamber 112 may have primary and secondary reaction stages. The heat recovery unit 128 may also have several cooling stages, such as a series of interconnected cyclones that help clean the material processed in different stages.

[0104] The embodiment of the apparatus 100 shown in Figure 3 can be formed as a greenfield plant or by incorporating it into existing equipment (retrofitting it to existing equipment).

[0105] As described above, one integration option involves providing a separate, dedicated reaction chamber for burning hydrogen and oxygen, which is positioned in close proximity to the existing equipment to supply heat to the existing reaction chamber and is operablely connected.

[0106] Regarding integration options, existing equipment used for hydrating materials in applications such as calcination typically has a flue gas outlet that releases into the atmosphere and a natural gas supply connected to the reaction chamber. Typically, air is used as an oxygen source and is transferred to the reaction chamber via a heat recovery unit, e.g., 128. Air is also typically used as a transfer fluid. Existing calcination equipment does not have a flue gas return line 120, an oxygen source 115, and a hydrogen source 114.

[0107] In one embodiment, the process of assembling the apparatus involves installing a flue gas transfer line 120 so that a flue gas flow, e.g. 118, is in fluid contact with the reaction chamber 112. As shown in Figure 3, the flue gas transfer line 120 is in fluid contact with the reaction chamber 112 via a heat recovery device 128. Next, a hydrogen source, e.g. 114, and optionally an oxygen source, e.g. 115, are connected to the reaction chamber 112.

[0108] Since the apparatus 100 shown in Figure 3 requires the use of steam acting as a transport gas or fluid medium to help transfer the material and / or processed material through the apparatus 100, the apparatus 100 should ideally be at or above the steam condensation temperature. The steam condensation temperature is approximately 100°C, which depends on the operating pressure of the apparatus 100. In one embodiment, the apparatus 100 is maintained at 160°C or higher.

[0109] To start the apparatus 100, the reaction chamber needs to be heated in a preheating step to a predetermined operating state or above as a steady state before the supply of materials to the reaction chamber begins. In one embodiment, the predetermined operating state is a temperature above the vapor condensation temperature. Heating the reaction chamber 112 above the vapor condensation temperature can be achieved by burning oxygen and hydrogen in the reaction chamber 112 to generate heat. Once sufficient heat is generated, the reaction chamber 112 must be above the vapor condensation temperature. The vapor produced by the combustion of hydrogen and oxygen can be transferred to the reaction chamber 112, for example, via the flue gas return line 120, to heat the reaction chamber 112.

[0110] In one embodiment, to prevent the reaction chamber 112 from overflowing with condensed vapor before the reaction chamber reaches its vapor condensation temperature, the reaction chamber 112 is typically heated to a temperature above the vapor condensation temperature by a preheating option other than combustion of pure hydrogen and oxygen within the reaction chamber 112 during the startup phase. Once the reaction chamber 112 is heated to a temperature above the vapor condensation temperature, the operating conditions can be changed, and then hydrogen and oxygen can be combusted within the reaction chamber 112 to generate heat and vapor. The vapor generated in the reaction chamber 112 can then be used to heat other components of the apparatus 100.

[0111] In one embodiment, at least the reaction chamber 112 is preheated in the startup phase using an external heat source, such as steam from another location within the plant / facility, before the combustion of hydrogen and oxygen. For example, if the plant / facility is a bauxite refinery, steam generated during the digestion of bauxite may be transferred to the reaction chamber 112 via a steam source 130, a return line 120, and a heat recovery unit 128.

[0112] In one embodiment, preheating the reaction chamber 112 in the startup phase includes generating heat by burning natural gas and oxygen within the reaction chamber 112. Once the reaction chamber 112 reaches a temperature above the vapor condensation temperature, the operating conditions are changed, and hydrogen is used for combustion with oxygen instead of natural gas.

[0113] The transition from natural gas to hydrogen may be a gradual transition. For example, preheating of the reaction chamber 112 may begin with 100% natural gas, and over a period of time, or once certain reaction chamber conditions are met, a portion of the natural gas may be replaced with hydrogen until the natural gas is completely replaced by hydrogen. The natural gas may be completely replaced just before the reaction chamber 112 reaches a predetermined operating state.

[0114] Alternatively, preheating of the reaction chamber 112 during the startup phase is initiated by burning a lean fuel mixture with hydrogen, which is then transitioned to a hydrogen-rich fuel mixture until a predetermined operating state is achieved, at which point the hydrogen-rich fuel mixture is replaced with 100% hydrogen.

[0115] In one embodiment, the reaction chamber 112 is heated upstream of the reaction chamber 112, such as at the location of the heat recovery device 128, and the heat is transferred to the reaction chamber 112, thereby heating it to a temperature above the condensation temperature of the vapor.

[0116] If the material source 116 provides a material having chemically bonded oxygen, preheating the reaction chamber 112 may include transferring oxygen from the oxygen source 115 to the reaction chamber 112, where the oxygen is first burned together with hydrogen from the hydrogen source 114 to generate heat, heating the reaction chamber 112 to a temperature above the vapor condensation temperature. The material having chemically bonded oxygen is then transferred to the reaction chamber 112 to react with hydrogen.

[0117] Before the material containing chemically bonded oxygen is transferred to the reaction chamber 112, the supply of oxygen from the oxygen source 115 can be reduced to, for example, 0%. Alternatively, the reduction of oxygen from the oxygen source 115 and the transfer of the material containing chemically bonded oxygen to the reaction chamber 112 can occur simultaneously. As a further alternative, the material containing chemically bonded oxygen can be transferred to the reaction chamber 112 before the oxygen from the oxygen source 115 is reduced.

[0118] In embodiments where an oxygen source 115 is required in addition to a material containing chemically bonded oxygen from a material source 116, the supply of oxygen from the oxygen source 115 can be reduced to the minimum amount of oxygen required from the oxygen source, depending on the processing conditions.

[0119] For example, if the processing conditions require that 80% of the oxygen be supplied from chemically bonded oxygen and 20% from oxygen source 115, then 100% of the oxygen from oxygen source 115 may be initially supplied to the reaction chamber 112 and burned together with hydrogen to generate heat. Then, the amount of oxygen from oxygen source 115 may be reduced to 20% over a predetermined period of time or after predetermined reaction conditions have been met, while simultaneously increasing the amount of chemically bonded oxygen from the material.

[0120] Preheating the reaction chamber 112 in the startup phase can involve combining different heating processes. For example, the reaction chamber 112 can be preheated by using an external heat source to burn a fuel mixture containing oxygen and hydrogen, or oxygen and natural gas.

[0121] Figure 4 shows one embodiment of a calcination plant 200 based on the apparatus 100 shown in Figure 3, for example, a calcination plant for calcining aluminum hydroxide to form alumina.

[0122] The following summary outlines the relationships between the components of apparatus 100 in Figure 3 and plant 200 in Figure 4. The reaction chamber 112 of apparatus 100 is the calcination section 212a of plant 200. The dryer 124 of apparatus 100 is the drying section 224a of plant 200. The heat recovery unit 128 of the device 100 is the heat recovery section 228a of the plant 200. The dust collection device 126 of the device 100 is a dust collection section 226a of the plant 200, which is in the form of a baghouse 226. The material source 116 of the device 100 is the material input 216 of the plant 200. The oxygen source 115 and hydrogen source 114 of device 100 are the oxygen input 215 and hydrogen input 214 of plant 200, respectively. The return line 120 of device 100 is the return steam line 220 of plant 200. The output line 117 of the device 100 is the outflow 217 of the processed material from the plant 200.

[0123] In the plant 200 illustrated in Figure 4, the direction of steam flow from the treated material outlet 217 to the baghouse 230 is from left to right. Therefore, the treated material outlet 217 is upstream of the reaction chamber 212, and the baghouse 226 is downstream of the reaction chamber 212.

[0124] The drying section 224a has a cyclone 240. The material is supplied to the material input 216, where the above flow of steam passing through the plant 200 carries the material to the cyclone 240. At least some, typically most, of the surface-bound water is removed from the material during transport from the input 216 to the cyclone 240. The cyclone 240 cleans the material, and dust and other unwanted particulate matter are transferred to the baghouse 226. The cleaned material is then transferred from the cyclone 240 to the calcination section 212a.

[0125] The calcination section 212a has cyclones 242a and 242b located downstream of the reaction chamber 212. The purified material is supplied from cyclone 240 of the drying section 224a to a position upstream of cyclone 242b, where steam then transfers the purified material to the downstream cyclone 242b to further purify the material. The further purified material (along with any processed material formed as a result of calcination in cyclone 242b) is then transferred to the reaction chamber 212. Hydrogen input 214 and oxygen input 215 are located just upstream of the reaction chamber 212. Hydrogen and oxygen are supplied to the reaction chamber 212 through their respective inputs 214 and 215, where they are burned to produce heat and steam. This heat calcines the material to form the processed material in the reaction chamber 212. Steam is also produced in the reaction chamber by the dehydration (i.e., calcination) of the material. Steam is also generated by the evaporation of surface moisture from the material in the drying section 224a. Next, the majority of the material present in the reaction chamber is processed to form the processed material in the reaction chamber. For example, if the material is a hydrate, the processed material is the dehydrated form of the hydrate.

[0126] Next, the processed material, along with all the remaining purified material, is transferred from the reaction chamber 212 to the cyclone 242a, where the remaining purified material is calcined to form the processed material.

[0127] The majority of the calcination of the purified material, at least 80%, generally takes place in the reaction chamber 212.

[0128] The steam generated in the reaction chamber 212 is transferred through the plant to the baghouse 226. This transfer of steam from the reaction chamber 212 to the baghouse 226 helps to transfer the material from the material input 216 to the cyclone 240, at least partially. Leaving the baghouse 226, the steam is split into a return steam line 220 and a steam source 230.

[0129] After the material has been processed in the reaction chamber 212 (i.e., the formed material has been obtained), it is then transferred to the heat recovery stage 228a. The heat recovery stage 228a has several cyclones 244 that clean and cool the processed material. The processed material passes through the final cyclone 246 before passing through the processed material outlet 217. The return steam line 220 is in fluid contact with the final cyclone 246. The steam in the return steam line 220 fluidizes and transports the material and processed material within the plant 200. [Examples]

[0130] Example 1 - Modeling of a 200-scale charcoal plant The calcination plant 200 shown in Figure 4 is modeled as a device that calcines aluminum hydroxide, such as gibbsite, forms alumina using SysCAD, and measures the flow rates of various inputs and outputs used in plant 200. In this example, aluminum hydroxide is the material (i.e., hydrate), and alumina is the processed material (e.g., dehydrated material).

[0131] In one example, 4.51 tons / hour of H2 and 38.2 tons / hour of O2 are supplied to the reaction chamber 212, and 284 tons / hour of aluminum hydrate is supplied to the input 216.

[0132] H2 and O2 were burned, generating 187 tons of steam per hour. This value of 187 tons / hour of steam also includes steam generated from the dehydration of aluminum hydroxide in reaction chamber 212.

[0133] The dehydration of aluminum hydroxide in the drying stage 224a and calcination stage 212a before aluminum hydroxide enters the reaction chamber 212 means that the total amount of steam generated from the calcination stage 212a and drying stage 224a and transferred to the baghouse 226 is 287 tons / hour.

[0134] 284 tons / hour of aluminum hydrate forms 205 tons / hour of alumina.

[0135] The 114 tons / hour of steam is transferred via the return steam line 220 and serves as a transport gas for particulate matter, such as aluminum hydroxide and alumina.

[0136] A plant used to calcine aluminum hydroxide using natural gas to form alumina has an energy requirement of approximately 3 GJ (gigajoules) / hour, while plant 200 has an energy requirement of approximately 2.9 GJ / hour.

[0137] The theoretical energy requirement for converting aluminum hydroxide to alumina in Plant 200 is approximately 1.8 to 2.0 GJ / hour. Please note that the difference between the theoretical and actual energy requirements is due to energy losses such as heat loss.

[0138] However, this calculation does not take into account the fact that the steam generated by Plant 200 may be used elsewhere to reduce the energy requirements of the alumina refinery's auxiliary equipment, so the use of Plant 200 may help improve the overall energy efficiency of the alumina refinery.

[0139] This embodiment focuses on calcining aluminum hydroxide to form alumina, but the apparatus and process described above are applicable to any material that can be dehydrated and calcined, subject to direct reduction processes including smelting and hydrogen reduction.

[0140] Example 2 - Simulation of steam conditions (similar to those for hydrogen-oxygen production steam) for calcining gibbsite (as a source of aluminum hydroxide) into alumina. The applicant operates a natural gas combustion calcination apparatus to dehydrate aluminum hydroxide in the form of gibbsite (Al2O3·3H2O) to alumina (Al2O3).

[0141] One difference between the current state of the applicant's natural gas combustion charring apparatus and the present invention is the use of a hydrogen-oxygen flame according to the present invention.

[0142] The characteristics of the hydrogen-oxygen flame include a combustion temperature significantly higher than that of the natural gas-air flame (see Table 1), and the fact that hydrogen burns in a pale blue flame, minimizing heat transfer by radiation.

[0143] [Table 1]

[0144] Hydrogen-oxygen The dominant heat transfer mechanisms in flames are convection and conduction through the vapor produced by combustion.

[0145] These heat transfer mechanisms allow, Hydrogen-oxygen The flame can be contained within the calcination apparatus or in another external reaction chamber (as described above), thereby transferring the generated steam and heat to the calcination apparatus, allowing most of the solids within the calcination apparatus to reach the target temperature.

[0146] The risks associated with the high-temperature region (related to the hydrogen-oxygen flame) within the calcination apparatus are at least substantially eliminated by a separate hydrogen combustion chamber.

[0147] Despite the explanation in the preceding paragraph, it should be noted that both options—containing the hydrogen-oxygen flame either inside or outside the calcination apparatus in a separate reaction chamber—are viable.

[0148] Another difference between the applicant's current natural gas combustion calcination apparatus and the present invention is the gas composition within the calcination apparatus. When oxygen is burned together with hydrogen, the flue gas of the calcination apparatus is considered to be pure vapor, and when oxygen-rich air is used, the flue gas is considered to be a combination of nitrogen and vapor.

[0149] Several studies have shown that the thermal decomposition rate of gibbsite is negative with respect to water vapor concentration. This means that the water vapor produced hinders further gibbsite calcination, while there is a counter-view that a large amount of water vapor pathway may proceed unimpeded through the boehmite, gamma, delta, theta, and ultimately alpha pathways.

[0150] Industrially, gibbsite calcination is carried out in flash calcination equipment and bubbling or circulating fluidized bed (CFB) reactors.

[0151] The CFB (Cold Fiber Filling) technique allows for scale-up without affecting product quality through the recirculation of solids within the CFB, resulting in a uniform temperature distribution and consistent product quality even under high volume and load fluctuations.

[0152] The main components of the CFB calcination process are two preheating stages, a calcination stage, and two cooling stages. The total residence time from when the feed material is supplied to the process until the alumina product is discharged is typically about 20 minutes. The CFB calcination equipment is usually operated in the range of 900-1000°C, depending on the product quality target. The material is held at the target temperature for 6 minutes.

[0153] The primary reason for performing this example was to simulate steam conditions (similar to hydrogen-oxygen-producing steam conditions) for calcining gibbsite into alumina under conditions that replicate a typical circulating fluidized bed calcination apparatus.

[0154] The test work was carried out in a laboratory-scale circulating fluidized bed reactor.

[0155] Methodology of testing procedures The calcination of gibbsite in a steam environment was tested using an 85mm diameter CFB reactor equipped with an external electric furnace.

[0156] Before each test, the gibbsite was dried at 105°C to remove all free moisture. Next, the dried solid was placed in a pressure feeder.

[0157] The furnace was heated to the target temperature. Low-flow nitrogen was introduced into the system at the following points: • Pressure feeder; • Loop sealing of recirculation lines; • Sample point at the bottom of the furnace.

[0158] These nitrogen flows were necessary to prevent vapor from condensing and causing blockages in the colder parts of the system.

[0159] Next, steam was introduced at the target flow rate, and once the temperature inside the reactor stabilized, approximately 1.5 kg of solid material was introduced into the system via a pressure feeder.

[0160] Once the solid material reached the target temperature, it was retained within the system for the required period before being sampled in a collection flask at the bottom of the furnace.

[0161] Nitrogen was introduced into the flask, which helped to cool the solids in an inert atmosphere and also to remove vapors from the solids before water condensed in the collection flask.

[0162] result The following test conditions were used to simulate hydrogen combustion using oxygen in the applicant's calcination apparatus.

[0163] [Table 2]

[0164] Due to the small size of the apparatus and the large heat loss in the surrounding area, vapor condensation occurred at the discharge alumina port, causing alumina blockage during testing. For this reason, nitrogen was introduced as an inert gas at an increased rate to prevent vapor condensation from causing material blockage.

[0165] Once the blockage in the material was cleared by the flow of inert gas, the following results were obtained by calcining the gibbsite.

[0166] X-ray diffraction (XRD) XRD was used to identify the alumina phase formed during the calcination process. Characteristic patterns of the two submitted samples are shown in Figure 5.

[0167] From Figure 5, the following points can be understood. 1. Gibbsite was calcined, forming mainly gamma-alumina and theta-alumina phases. - This is consistent with the applicant's quality specifications for smelter-grade alumina products. 2. Gibbsite was calcined, forming a small amount of alpha-alumina phase. - This is consistent with the applicant's quality specifications for smelter-grade alumina products.

[0168] Loss due to ignition (LOI) The amount of gibbsite converted to the alumina phase was measured using the loss due to ignition. From this, the following could be determined: 1. The moisture content on the alumina surface was negligible, and the residual moisture content was less than 0.05%. 2. The conversion of gibbsite to alumina was approximately 99.7% complete. - This is consistent with the applicant's quality specifications for smelter-grade alumina products.

[0169] Consideration The results above indicate that gibbsite can be calcined into alumina by vapor produced under conditions of a hydrogen-oxygen flame.

[0170] Furthermore, these results indicate that the manufactured alumina is suitable to meet the applicant's smelter-grade alumina specifications.

[0171] Furthermore, the formation of a majority of gamma-alumina and theta-alumina supports the following calcination pathways expected under high-steam conditions: Gibbsite → (Boehmite) → Gamma alumina → (Delta alumina) → Theta alumina → Alpha alumina.

[0172] Although the phases indicated in parentheses above were not directly observed, technical literature suggests that these phases may have been present during the decomposition reaction.

[0173] The use of nitrogen described above in the test work to manage material handling issues was necessary due to the small, laboratory-scale nature of the apparatus that causes vapor condensation on an air-exposed surface. This is not expected to hinder scale-up.

[0174] The above test operation of calcining gibbsite into alumina demonstrates to the inventor that hydrogen can be used as a combustion fuel instead of natural gas for calcination processes such as the formation of alumina by calcination of aluminum hydroxide and the formation of anhydrous gypsum by dehydration, as well as for reduction processes.

[0175] Many modifications can be made to the embodiments of the present invention described above without departing from the essence and scope of the present invention. One aspect of the present invention is shown below, but the present invention is not limited thereto. [Invention 1] A process for processing materials by calcination or reduction processes, A process comprising reacting hydrogen and oxygen in a reaction chamber to generate heat and vapor, discharging vapor from the reaction chamber, using this heat to process a material and produce a processed material, and returning at least a portion of the vapor discharged from the reaction chamber back to the process. [Invention 2] The process according to Invention 1, comprising generating steam by reacting hydrogen and oxygen through the combustion of hydrogen and oxygen gases. [Invention 3] The process according to Invention 1, comprising generating vapor by reacting hydrogen and oxygen through a reaction between hydrogen and chemically bonded oxygen. [Invention 4] The process according to any one of claims 1 to 3 of the invention, wherein when forming the processed material, steam is generated in a reaction chamber, for example, by dehydrating the material. [Invention 5] A process according to any one of claims 1 to 4 of the invention, comprising maintaining a vapor at a temperature above its condensation temperature. [Invention 6] The process according to any one of claims 1 to 5 of the invention, wherein the transport gas in the process is, for example, steam generated in the reaction chamber to transport the material to be processed and / or the processed material into and / or out of the reaction chamber. [Invention 7] The process according to any one of claims 1 to 6 of the invention, further comprising using steam generated in a reaction chamber as a heat transfer medium in the process. [Invention 8] The process according to any one of claims 1 to 7 of the invention, wherein after the process has reached a predetermined condition such as a steady state, the process discharges a flue gas, which is at least 95 volume percent vapor, from the reaction chamber. [Invention 9] The process according to any one of claims 1 to 7 of the invention, wherein after the process has reached a predetermined condition such as a steady state, the process discharges a flue gas, which is 100% by volume vapor, from the reaction chamber. [Invention 10] The process according to any one of claims 1 to 9 of the invention, wherein the material and the processed material are in particulate form. [Invention 11] A process according to any one of claims 1 to 10 of the invention, comprising transferring at least a portion of the steam generated in the process and discharged from the process to components used in a plant, for example, an industrial facility. [Invention 12] The process according to invention 11, wherein the components include a mechanical steam recompressor, a thermal steam recompressor, a generator and / or a heat recovery unit. [Invention 13] The process according to any one of claims 1 to 12 of the invention, wherein the material is a hydrate and the treated material is a dehydrated form of the hydrate. [Invention 14] The method according to any one of Inventions 1 to 12, wherein the material is a metal oxide and the treated material is a reduced form of the metal oxide. [Invention 15] The process according to Invention 1, which is a cauterization process for dehydrating the aforementioned material. [Invention 16] The process according to Invention 1, which is part of a reduction process such as a smelting process or a direct reduction process for forming a base metal. [Invention 17] A process for processing materials by calcination or reduction processes, A process comprising burning hydrogen and oxygen to generate heat and steam, using this heat to process a material and produce a processed material, and using the steam generated from the combustion as a transfer gas in the process. [Invention 18] The process according to invention 17, further comprising discharging steam from the process and then transferring at least a portion of the discharged steam back into the process. [Invention 19] The process according to invention 17 or invention 18, comprising burning hydrogen and oxygen in a reaction chamber to generate steam and heat, and processing a material in the reaction chamber. [Invention 20] The process according to invention 17 or invention 18, comprising burning hydrogen and oxygen to generate vapor and heat in one reaction chamber, and transferring the vapor and heat to a second reaction chamber, in which the material is processed. [Invention 21] An apparatus for performing the process described in any one of inventions 1 to 20. [Invention 22] An apparatus for processing materials, The device is A reaction chamber configured for processing materials; A hydrogen source capable of reacting with oxygen in this reaction chamber, for processing materials in the reaction chamber and producing a flue gas containing the processed materials and vapors; The exit for processed materials; Flue gas outlet; and A first line for supplying at least a portion of the flue gas discharged through the flue gas outlet to the device. A device that includes this. [Invention 23] The apparatus according to invention 22, further comprising a second line for supplying at least a portion of the flue gas discharged through the flue gas outlet to a component other than the reaction chamber. [Invention 24] The apparatus according to any one of claims 21 to 23 of the invention, comprising a first reaction chamber for processing the aforementioned material and a second reaction chamber for burning hydrogen and oxygen to generate heat for use in the first reaction chamber. [Invention 25] A plant for processing materials, comprising an apparatus for processing materials as described in any one of inventions 21 to 24. [Invention 26] The process of starting up a plant for processing materials, The plant includes a reaction chamber where the materials are processed. A preheating step of heating the reaction chamber until predetermined conditions are met; and Next, the step of starting to supply material to the reaction chamber is included, process. [Discussion 27] The process according to invention 26, wherein the preheating step comprises burning any suitable reactant source, including a hydrocarbon fuel, in a reaction chamber. [Invention 28] The process according to invention 26, wherein the preheating step includes burning hydrogen in a reaction chamber to generate heat.

Claims

1. A process for calcining and / or reducing materials, A process comprising reacting hydrogen and oxygen in a reaction chamber to generate heat and vapor, discharging the vapor from the reaction chamber, using this heat to calcine and / or reduce a material to produce a calcined and / or reduced material, and returning at least a portion of the vapor discharged from the reaction chamber to the process, The vapor generated in the reaction chamber is used as a transport gas and heat transfer medium for the material or the calcined and / or reduced material in the process. process.

2. The process according to claim 1, comprising generating steam by reacting hydrogen and oxygen through the combustion of hydrogen and oxygen gases.

3. The process according to claim 1, comprising generating vapor by reacting hydrogen and oxygen through a reaction between hydrogen and chemically bonded oxygen.

4. The process according to any one of claims 1 to 3, comprising generating vapor in a reaction chamber when forming the calcined and / or reduced material.

5. The process according to any one of claims 1 to 4, comprising maintaining the steam at a temperature above its condensation temperature.

6. The process according to any one of claims 1 to 5, wherein, after the process has reached a predetermined condition, the process includes discharging a flue gas, which is at least 95% by volume of vapor, from the reaction chamber.

7. The process according to any one of claims 1 to 5, wherein, after the process has reached a predetermined condition, the process includes discharging a flue gas, which is 100% by volume of vapor, from the reaction chamber.

8. The process according to any one of claims 1 to 7, wherein the material and the calcined and / or reduced material are in particulate form.

9. The process according to any one of claims 1 to 8, comprising transferring at least a portion of the steam generated in the process and discharged from the process to equipment used in the plant.

10. The process according to claim 9, wherein the apparatus includes a mechanical steam recompressor, a thermal steam recompressor, a generator and / or a heat recovery unit.

11. The process according to any one of claims 1 to 10, wherein the material is a hydrate, and the calcined and / or reduced material is a dehydrated form of the hydrate.

12. A process according to any one of claims 1 to 10 for reducing the material, wherein the material is a metal oxide and the reduced material is a reduced form of the metal oxide.

13. The process according to claim 1, which is a process for burning the material in order to dehydrate the material.

14. The process according to claim 1, which is a process for reducing the material in order to form a base metal.

15. A process for calcining and / or reducing materials, A process comprising: burning hydrogen and oxygen to generate heat and steam; using this heat to calcine and / or reduce a material to produce a calcined and / or reduced material; and using the steam produced from the combustion as a transport gas and heat transfer medium for the material and the calcined and / or reduced material in the process.

16. The process according to claim 15, further comprising discharging steam from the process and then transferring at least a portion of the discharged steam back into the process.

17. The process according to claim 15 or 16, comprising burning hydrogen and oxygen in a reaction chamber to generate steam and heat, and calcining and / or reducing a material in the reaction chamber.

18. The process according to claim 15 or 16, comprising burning hydrogen and oxygen to generate vapor and heat in one reaction chamber, and transferring the vapor and heat to a second reaction chamber, in which a material is calcined and / or reduced.

19. An apparatus for performing the process described in any one of claims 1 to 18.

20. A apparatus for calcining and / or reducing materials, The device is At least one reaction chamber configured to burn hydrogen and oxygen to generate a flue gas containing vapor and heat, and to use the heat to calcine and / or reduce a material to produce calcined and / or reduced material; Flue gas containing steam for calcining and / or reducing materials, and hydrogen and oxygen sources for generating heat; Outlet for calcined and / or reduced material; Flue gas outlet; and A first line for supplying at least a portion of the flue gas discharged through the flue gas outlet to the apparatus as a heat transfer medium and as a transport gas for the material and the calcined and / or reduced material in the apparatus. A device that includes this.

21. The apparatus according to claim 20, further comprising a second line for supplying at least a portion of the flue gas discharged through the flue gas outlet to an apparatus separate from the reaction chamber.

22. The apparatus according to claim 20 or 21, wherein the reaction chamber comprises a first reaction chamber for calcining and / or reducing the material, and a second reaction chamber for burning hydrogen and oxygen to generate heat for use in the first reaction chamber.

23. A plant for calcining and / or reducing materials, comprising an apparatus for calcining and / or reducing materials as described in any one of claims 19 to 22.

24. A process for starting up a plant for calcining and / or reducing materials, The plant includes a reaction chamber in which materials are calcined and / or reduced. A preheating step in which the reaction chamber is heated until predetermined conditions are met; Steps include starting the supply of materials to the reaction chamber; A step of reacting hydrogen and oxygen in a reaction chamber to generate heat and vapor; The steps of using this heat to calcine and / or reduce the material to produce a calcined and / or reduced material; and A step of returning at least a portion of the vapor discharged from the reaction chamber back to the process. including, It is a process, The vapor generated in the reaction chamber is used as a transport gas and heat transfer medium for the material or the calcined and / or reduced material in the process. process.

25. The process according to claim 24, wherein the preheating step comprises burning any suitable reactant source, including a hydrocarbon fuel, in a reaction chamber.

26. The process according to claim 24, wherein the preheating step includes burning hydrogen in a reaction chamber to generate heat.

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