Catalytic decomposition of ammonia by water vapor as a heat transfer medium

Abstract

The present invention relates to a system and method for preparing H2 by catalytic decomposition of NH3. Water is used as a heat transfer medium to recover process heat. The process heat is received by water or steam and then discharged to NH3, resulting in the heating and evaporation of the NH3. Using water or steam as a heat transfer medium offers advantages, particularly in terms of economy and safety.

Claims

[Claim 1] NH ３ By catalytic decomposition of H ２ A plant for generating, A combustion device (18) for burning combustion gas, the combustion device (18) generates heat of combustion and heat of combustion exhaust gas, By absorbing heat from heated water, liquid NH ３ NH to evaporate ３ Evaporation device (14), The NH ３ downstream of the evaporation device (14) in the flow direction of the NH ３ is a catalytic decomposition device (24) for the catalytic decomposition of the evaporated NH ３ which absorbs the heat of combustion generated in the combustion device (18) and generates a product gas containing H ３ and N ２ and ２ a catalytic decomposition device (24) for the catalytic decomposition of the evaporated NH ３ which absorbs the heat of combustion generated in the combustion device (18) and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ ... and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N ２ and generates a product gas containing H ２ and N <00000 Downstream of the combustion device (18) in the flow direction of the combustion exhaust gas, a combustion exhaust gas heat exchanger (52) for heating water by absorbing heat from the combustion exhaust gas, and / or in the flow direction of the generated gas, the NH ３ Downstream of the decomposition device (24), there is a generated gas heat exchanger (26) for heating water by absorbing heat from the generated gas, The combustion exhaust gas heat exchanger (52) and / or the generated gas heat exchanger (26) from the NH ３ Conduit (63) for heated water to the evaporation device (14) and A plant equipped with these features. [Claim 2] At least 500 mol·h －１ H ２ The plant according to claim 1, which is designed for throughput based on the above. [Claim 3] At least 50m ３ Liquid NH having volume ３ The plant according to claim 1 or 2, comprising a tank (10) for use. [Claim 4] Said NH ３ The disassembly device (24) is NH ３ The plant according to any one of claims 1 to 3, comprising at least three catalyst beds containing a decomposition catalyst. [Claim 5] Said NH ３ Disassembly device is NH ３ The catalyst bed comprises at least one catalyst bed containing a decomposition catalyst, and the NH ３ The plant according to any one of claims 1 to 4, wherein the length of the catalyst bed in the flow direction is at least 1.0 m. [Claim 6] The plant according to any one of claims 1 to 5, wherein the combustion device (18) comprises at least three burners for burning the combustion gas. [Claim 7] The plant according to any one of claims 1 to 6, wherein the combustion exhaust gas heat exchanger (52) and / or the generated gas heat exchanger (26) is a tube heat exchanger or a shell-and-tube heat exchanger. [Claim 8] Said NH ３ In the flow direction, the NH ３ Upstream of the evaporation device (14), the NH ３ By absorbing heat from the water released from the evaporation device (14), NH ３ The plant according to any one of claims 1 to 7, comprising a preheater (13) for heating. [Claim 9] H ２ The plant according to any one of claims 1 to 8, comprising an apparatus for the purification of (31). [Claim 10] The aforementioned H ２ The plant according to claim 9, wherein the apparatus for purification is a pressure swing adsorption device (31). [Claim 11] Said NH ３ In the flow direction, the NH ３ Upstream of the evaporation device (14), preferably upstream of any preheater (13), heat is absorbed from the heated cooling water to create NH ３ The plant according to any one of claims 1 to 10, comprising a preheating device (70) for preheating. [Claim 12] The heated cooling water is H in the direction of the flow of the generated gas. ２ The plant according to claim 11, wherein the process cooler (29) exits upstream of the device for purification, preferably upstream of the pressure swing adsorption device (31). [Claim 13] The heated cooling water is H ２ The plant according to claim 11 or 12, which is discharged from the heat exchanger (34) of the compressor (33). [Claim 14] The heating and cooling water is the NH ３ The plant according to any one of claims 11 to 13, wherein the steam condensate of the evaporation device (14) exits from a heat exchanger (83) downstream of any preheater (13), preferably downstream of a preheater (13). [Claim 15] Said NH ３ In the flow direction, the NH ３ Upstream of the evaporation device (14), preferably upstream of any preheater (13), preferably downstream of any preheating device (70), heat is absorbed from the water to NH ３ An additional heat exchanger (73) for preheating, Downstream of the combustion exhaust gas heat exchanger (52) in the direction of the combustion exhaust gas flow, there is a further heat exchanger (71) for heating the water by absorbing heat from the combustion exhaust gas. A plant according to any one of claims 1 to 14, comprising: [Claim 16] The plant according to claim 15, wherein the additional heat exchanger (73) and the further heat exchanger (71) are connected to each other via a ring conduit (74) for circulating the water. [Claim 17] At least two heat exchangers, preferably, The generated gas heat exchanger (26) and the combustion exhaust gas heat exchanger (52), or The combustion exhaust gas heat exchanger (52) and the further heat exchanger (71), or The preheater (13) and the generated gas heat exchanger (26), or The preheater (13) and the combustion exhaust gas heat exchanger (52) A plant according to any one of claims 1 to 16, comprising: [Claim 18] At least three heat exchangers, preferably The preheater (13), the generated gas heat exchanger (26), and the combustion exhaust gas heat exchanger (52), or The preheating device (70), the preheater (13), and the generated gas heat exchanger (26), or Preheating device (70), preheater (13), and combustion exhaust gas heat exchanger (52) A plant according to any one of claims 1 to 17, comprising: [Claim 19] The plant according to any one of claims 1 to 18, comprising at least four heat exchangers, preferably the preheating device (70), the preheater (13), the generated gas heat exchanger (26), and the combustion exhaust gas heat exchanger (52). [Claim 20] The plant according to any one of claims 1 to 19, comprising at least five heat exchangers, preferably the preheating device (70), the additional heat exchanger (73), the preheater (13), the generated gas heat exchanger (26), and the combustion exhaust gas heat exchanger (52). [Claim 21] The aforementioned H ２ Apparatus for purification of H, preferably from the pressure swing adsorption device (31) to the combustion device (18) ２ The plant according to any one of claims 1 to 20, further comprising a return conduit (38) and a branch conduit (39) for the residual gas mixture remaining after the removal of the gas. [Claim 22] H ２ Use of the plant according to any one of claims 1 to 21 for the generation of. [Claim 23] NH ３ By catalytic decomposition of H ２ A method for generating, (a) A process of burning combustion gas to generate heat of combustion and heat of combustion exhaust gas, (e) By absorbing heat from heated water, liquid NH ３ The process of evaporating (f) NH evaporated in step (e) ３ The material is catalytically decomposed, and the heat of combustion generated in step (a) is absorbed, H ２ and N ２ A process of producing a generated gas containing; and (g) A step of heating water by absorbing heat from the combustion exhaust gas generated in step (a) and / or the generated gas generated in step (f), and introducing the heated water into step (e). Methods that include... [Claim 24] In step (f), at least 500 mol·h －１ H ２ The method according to claim 23, wherein throughput based on is achieved. [Claim 25] The liquid NH ３ However, in step (e), at least 50 m ３ The method according to claim 23 or 24, wherein the contents are drawn from a tank having the volume of the specified volume. [Claim 26] NH in process (f) ３ The catalytic decomposition of the above is each NH ３ The method according to any one of claims 23 to 25, wherein the method is carried out over at least three catalyst beds containing a decomposition catalyst. [Claim 27] The catalytic decomposition in step (f) is NH ３ This is carried out across at least one catalyst bed containing a decomposition catalyst, NH ３ The method according to any one of claims 23 to 26, wherein the length of the catalyst bed in the flow direction is at least 1.0 m. [Claim 28] The method according to any one of claims 23 to 27, wherein the combustion gas is burned by at least three burners in step (a). [Claim 29] The method according to any one of claims 23 to 28, wherein the heating in step (g) is carried out in a heat exchanger selected from a tube heat exchanger and a shell-and-tube heat exchanger. [Claim 30] (d) By absorbing heat from the water obtained in step (e), NH ３ Additional steps to heat The method according to any one of claims 23 to 29, including the method described in any one of claims 23 to 29. [Claim 31] H ２ Purification of H ２ The method according to any one of claims 23 to 30, wherein the purification is carried out in an apparatus, preferably a pressure swing adsorption device (31). [Claim 32] (b) By absorbing heat from the heated cooling water, NH ３ An additional step to preheat The method according to any one of claims 23 to 30, including the method described in any one of claims 23 to 30. [Claim 33] The heated cooling water is H ２ Purification, preferably before pressure swing adsorption, is performed, and / or after compression, H ２ The method according to claim 26, wherein heat is absorbed in advance. [Claim 34] (c) By absorbing heat from water, NH ３ An additional step of preheating the water, and then heating the water obtained in this way by absorbing heat from the combustion exhaust gas. The method according to any one of claims 23 to 33, including the method described in that claim. [Claim 35] The method according to claim 33, wherein the water is circulated. [Claim 36] H ２ Apparatus for the purification of, preferably the pressure swing adsorption device (31), in which the H ２ The method according to any one of claims 23 to 35, wherein the residual gas mixture remaining after the removal of the gas is returned via a return conduit (38) and supplied to the combustion device (18) via a branch conduit (39).

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