Low-temperature NH3 reforming method coupled with heat pump

Abstract

The invention relates to a process for transferring heat to a stream comprising NH3, the process comprising: (i) providing a stream comprising a heat transfer medium wherein the stream has a pressure in the range of from 1 to 100 bar (absolute value) and a temperature equal to or greater than 105 DEG C; (ii) raising the temperature of the stream provided in (i) by transferring heat from a chemical conversion process, from a physicochemical process, or from ambient heat, or from a combination of two or more thereof to the heat transfer medium to obtain a stream having a temperature in the range of from 125 DEG C to 750 DEG C; (iii) increasing the pressure of the stream obtained in (ii) to obtain a compressed stream having a temperature in the range from 50 DEG C to 800 DEG C; (iv) providing a stream comprising NH3, wherein the stream comprising NH3 has a temperature in the range from-33 DEG C to 100 DEG C; (v) heating the stream provided in (iv), where heating comprises transferring heat from the compressed stream obtained in (iii) to the stream provided in (iv) to obtain a heated stream comprising NH3, the heated stream having a temperature in the range of from 25 DEG C to 750 DEG C; (vi) expanding the compressed flow obtained in (v); (vii) optionally recycling at least a portion of the stream obtained in (vi) to (i).

Description

Technical Field

[0001] The present invention relates to a method for transferring heat to a stream containing NH3. Background Art

[0002] Providing heat for endothermic processes such as ammonia cracking is currently accomplished by burning fossil fuels or by direct electric heating. Fossil fuels are generally preferred to direct electric heating due to their lower efficiency and therefore lower cost.

[0003] Heat pumps achieve a temperature increase by a much greater amount of heat than the amount of electricity used by cleverly using electrical energy in a thermodynamic cycle. To increase the temperature according to the Carnot cycle, the coefficient of performance (COP) is calculated according to Formula 1:

[0004] ε 卡诺WP =1 / (1-T 低 / T 高 )(I),

[0005] where ε 卡诺WP is the coefficient of performance of the Carnot cycle of the heat pump, T 低 is the absolute temperature (in Kelvin) of the heat absorption, and T 高 is the absolute temperature at which the heat is released. The latter temperature must be at least equal to the temperature at which the process to be heated is carried out.

[0006] Until now, heat pumps have been used and designed to supply heat at a maximum temperature of approximately 150°C. Many technically relevant processes require large amounts of heat at temperatures significantly above this value. Examples include the melting of metals, distillation processes, and endothermic chemical reactions. For thermodynamic reasons, endothermic chemical reactions typically occur at high temperatures.

[0007] DE 2951188 A1 relates to a method for utilizing waste heat from endothermic processes, wherein heat is initially provided from an external heat source at a high temperature level and residual heat from the reaction is obtained at a low temperature level, wherein the low-temperature residual heat is recycled into the endothermic reaction by means of a heat pump.

[0008] DE 3209642 A1 discloses a process heat generating plant for the combined generation of high-temperature heat and process steam.

[0009] V. Singh et al., “Investigation of new mechanical heat pump systems for heat upgrading applications,” Int. J. Energy Ress. 2018, 42, 3078–3090, disclose examples of multi-stage, ultra-high-temperature heat pumps with different heat transfer media that can be used in process engineering and other applications.

[0010] In the course of converting technical processes to sustainable energy sources, it is therefore desirable to further increase the temperature levels hitherto achievable by heat pumps in order to reduce the dependence of processes requiring heat at high temperature levels on other energy sources.

[0011] The object of the present invention is therefore to provide a method in which the utilization of heat (e.g. by means of a heat pump) is not limited to primary energy sources and in particular further valorization of sustainable energy sources or nuclear energy. In particular, the object of the present invention is to use heat transfer concepts for reactions involving ammonia conversion and in particular for ammonia reforming, wherein the heat transfer concepts involve valorization of heat that does not originate from primary energy sources, and in particular involve valorization of waste heat or other available low-temperature heat. DETAILED DESCRIPTION

[0012] Thus, it has surprisingly been found that heat sources at low temperatures can be used to upgrade these heat sources to usable thermal energy, whereby a coefficient of performance (COP) greater than 1 can be obtained. In particular, it has been unexpectedly found that the use of a cascade of heat pumps is particularly advantageous for achieving energy efficiency and reducing dependence on primary energy sources, whether these are sustainable or not. Thus, by a suitable choice of the heat transfer medium, the upgrading of the heat sources makes it possible to directly supply heat at very high temperatures, for example by supplying heat by superheated saturated steam, in order to provide the necessary temperatures in processes involving ammonia conversion, in particular in ammonia reforming. In particular, it has been found that the use of high-temperature heat pumps allows the electrification of said processes, which are difficult to achieve electrically heated, and in particular with a better electrical efficiency COP greater than 1. 实际 .

[0013] The present invention specifically relates to a method for transferring heat from a chemical conversion process reaction to a stream containing NH3, wherein excess heat from the chemical process and / or ambient heat is used to heat a heat transfer medium. The heat transfer medium is then compressed to further increase its temperature. The resulting compressed stream is then used to heat the stream containing NH3. Thus, excess heat from the chemical process and / or ambient heat is not used directly to heat the NH3, but is instead transferred via the heat transfer medium.

[0014] The present invention therefore relates to a method for transferring heat to a stream containing NH3, the method comprising:

[0015] (i) providing a stream comprising a heat transfer medium,

[0016] wherein the stream has a pressure in the range from 1 to 100 bar (absolute) and a temperature equal to or greater than 105° C.;

[0017] (ii) increasing the temperature of the stream provided in (i) by transferring heat from a chemical conversion process, from a physicochemical process, or from ambient heat, or from a combination of two or more thereof, to the heat transfer medium to obtain a stream having a temperature in the range of from 125° C. to 750° C.;

[0018] (iii) increasing the pressure of the stream obtained in (ii),

[0019] to obtain a compressed stream having a temperature in the range from 50° C. to 800° C.;

[0020] (iv) providing a stream comprising NH 3 , wherein the stream comprising NH 3 has a temperature in the range from -33° C. to 100° C.;

[0021] (v) heating the stream provided in (iv), wherein heating comprises transferring heat from the compressed stream obtained in (iii) to the stream provided in (iv) to obtain a heated stream comprising NH3, the heated stream having a temperature in the range from 25°C to 750°C;

[0022] (vi) expanding the compressed stream obtained in (v);

[0023] (vii) optionally recycling at least a portion of the stream obtained in (vi) to (i).

[0024] Preferably, the heat transfer medium is selected from the group consisting of evaporating and condensing working fluids and supercritical working fluids, wherein preferably the heat transfer medium is water, wherein more preferably the heat transfer medium is steam.

[0025] Preferably, the stream provided in (i) has a temperature equal to or greater than 150°C, more preferably in the range of from 200°C to 550°C, more preferably in the range of from 250°C to 350°C.

[0026] Preferably, the stream provided in (i) has a pressure in the range of from 5 to 50 bar (absolute), more preferably in the range of from 10 to 40 bar (absolute), more preferably in the range of from 20 to 30.

[0027] Preferably, the stream provided in (i) comprises from 0 to 1 vol.-%, more preferably from 0 to 0.1 vol.-%, more preferably from 0 to 0.01 vol.-% NH3.

[0028] Preferably, from 95 to 100% by volume, more preferably from 99 to 100% by volume, more preferably from 99.9 to 100% by volume of the stream provided in (i) consists of the heat transfer medium.

[0029] Preferably, the heat transfer according to (ii) is performed using a heat exchanger.

[0030] Preferably, the ambient heat transferred according to (ii) is heat from the environment, preferably heat from one or more of air, water, soil and solar radiation (including combinations of two or more thereof).

[0031] Preferably, the heat from the chemical conversion process transferred according to (ii) is obtained from an exothermic reaction, or wherein the heat from the chemical conversion process transferred according to (ii) is excess heat for carrying out an autothermal reaction or an endothermic reaction.

[0032] Where the heat from the chemical conversion process transferred according to (ii) is obtained from an exothermic reaction, it is preferred that the exothermic reaction comprises one or more of: methanol production, dimethyl ether production, NH3 production, ethylene epoxidation, sulfuric acid production and the selective oxidation of one or more of alkanes, alkenes and alkynes, preferably the selective oxidation of one or more of alkanes, alkenes and alkynes to acrolein or acrylic acid.

[0033] Where the heat from the chemical conversion process transferred according to (ii) is excess heat for carrying out an endothermic reaction, preferably the endothermic reaction comprises one or more of steam cracking, ethane dehydrogenation, propane dehydrogenation, butane dehydrogenation, steam reforming, dry reforming, styrene production, methanol reforming, dimethyl ether reforming, reverse water gas shift, alcohol dehydration and NH3 reforming.

[0034] Where the heat transferred from the chemical conversion process according to (ii) is excess heat for carrying out an autothermal reaction, it is preferred that the autothermal reaction is selected from the group consisting of: autothermal reforming of natural gas and hydrocarbons (including partial oxidation (POx) processes of hydrocarbons) wherein the hydrocarbons are selected from (C1-C 10 )alkanes, more preferably (C1-C8)alkanes, more preferably (C1-C7)alkanes.

[0035] According to the present invention, it is preferred that the stream obtained in (ii) has a temperature in the range of from 25°C to 750°C, more preferably in the range of from 100°C to 550°C, more preferably in the range of from 150°C to 300°C, more preferably in the range of from 180°C to 200°C.

[0036] Preferably, the heat transferred from the physicochemical process according to (ii) is obtained from an exothermic change in the aggregate state of the compound or material, more preferably from condensation and solidification of the compound or material. Particularly preferably, the heat transferred from the physicochemical process according to (ii) is obtained from vapor compression evaporation.

[0037] Preferably, in (ii), the heat transfer medium undergoes at least partial evaporation.

[0038] Preferably, a compressed stream having a pressure in the range from 1 to 250 bar (absolute), more preferably in the range from 5 to 150 bar (absolute), more preferably in the range from 10 to 100 bar (absolute), more preferably in the range from 20 to 90 bar (absolute) is obtained according to (iii).

[0039] Preferably, increasing the pressure of the stream according to (iii) is performed using a compressor.

[0040] Preferably, the process provides a coefficient of performance (COP) greater than 1, more preferably from 1.1 to 4, more preferably from 1.2 to 3, more preferably from 1.2 to 2, more preferably from 1.2 to 1.5.

[0041] Preferably, increasing the pressure of the stream according to (iii) is performed adiabatically.

[0042] Within the meaning of the present invention, an adiabatic or isothermal change of state is understood to be a change of state which is achieved close to a theoretical adiabatic or isothermal process.

[0043] Preferably, from 95 to 100 vol.-%, more preferably from 99 to 100 vol.-%, more preferably from 99.9 to 100 vol.-% of the stream provided in (iv) consists of NH3.

[0044] Preferably, the stream provided in (iv) has a temperature in the range from -33°C to 100°C, more preferably in the range from -15°C to 80°C, more preferably in the range from 0°C to 60°C, more preferably in the range from 15°C to 50°C, more preferably in the range from 25°C to 40°C.

[0045] Preferably, the stream provided in (iv) has a pressure in the range from 1 to 100 bar (abs), more preferably in the range from 20 to 35 bar (abs).

[0046] Preferably, the stream provided in (iv) has a flow rate of from 200 to 20,000 h. -1 In the range of, more preferably from 2,000 to 8,000h -1 Weight hourly space velocity in the range.

[0047] Preferably, the heating according to (v) comprises at least partially converting NH3 into N2 and H2, wherein the heating according to (v) preferably comprises converting from 1 to 100 vol.-%, more preferably from 15 to 50 vol.-% of the NH3.

[0048] Preferably, a compressed stream having a temperature in the range from 200 to 750°C, more preferably in the range from 300 to 550°C is obtained according to (v).

[0049] Preferably, a compressed stream is obtained according to (v) having a pressure in the range from 1 to 100 bar (abs), more preferably in the range from 20 to 35 bar (abs).

[0050] Preferably, the compressed stream obtained in (v) has the same pressure as the compressed stream obtained in (iii).

[0051] Preferably, the heating according to (v) is performed using a heat exchanger, wherein the heat exchanger is preferably the reactor containing the stream provided in (iv), more preferably the wall of the reactor containing the stream provided in (iv).

[0052] Preferably, a stream comprising NH3 is obtained according to (v) having a temperature in the range from 250 to 750°C, more preferably in the range from 290 to 310°C.

[0053] Preferably, the NH3-comprising stream is obtained according to (v) having a pressure in the range from 1 to 100 bar (abs), more preferably in the range from 10 to 40 bar (abs).

[0054] Preferably, the expansion according to (vi) is performed using a thermal expansion valve.

[0055] Preferably, the expanded stream obtained in (v) has the same pressure and temperature as the stream comprising the heat transfer medium provided in (i).

[0056] Preferably, the expanding the compressed stream according to (vi) is performed adiabatically.

[0057] Preferably, from 1 to 100% by volume, more preferably from 50 to 100% by volume, of the stream obtained in (vi) is recycled into (i) according to (vii).

[0058] Preferably, the stream obtained in (vi) is completely recycled into (i) according to (vii).

[0059] In case the stream obtained in (vi) is completely recycled into (i) according to (vii), it is preferred that steps (i) to (vii) are carried out in a closed system in which the stream comprising the heat transfer medium is circulated.

[0060] According to the present invention, preferably, the method further comprises

[0061] (viii) feeding the heated stream comprising NH3 obtained in (v) into a first reactor to obtain a first product stream, wherein more preferably the heat of the first product stream is used in (ii) as at least part of the heat from the chemical conversion process that is transferred to the heat transfer medium.

[0062] In case the process further comprises (viii) feeding the heated stream comprising NH3 obtained in (v) into a first reactor to obtain a first product stream, it is preferred that the heated stream obtained in (v) is fed into the first reactor having a temperature in the range from 200°C to 750°C, more preferably in the range from 250°C to 550°C.

[0063] Additionally and independently, it is preferred that the heated stream obtained in (v) is heated to 200 to 20,000 h. -1 In the range of 400 to 4,000 hours, more preferably -1 The gas hourly space velocity within the range is fed into the first reactor.

[0064] Additionally and independently, it is preferred that the first product stream obtained in (viii) has a temperature in the range from 110 to 350°C, more preferably in the range from 160 to 250°C.

[0065] Additionally and independently, it is preferred that from 1 to 75 mol-%, more preferably from 5 to 45 mol-%, of the NH3 contained in the heating stream fed to the first reactor is converted into N2 and H2, based on 100 mol-% NH3 contained in the heating stream fed to the first reactor.

[0066] Additionally and independently, preferably, the method further comprises

[0067] (ix) providing the first product stream obtained in (viii) as a stream comprising NH3 in a subsequent process for transferring heat to a stream comprising NH3 according to any one of the specific and preferred embodiments of the present invention, and heating the first product stream in (v) of said subsequent process to a temperature in the range of from 200°C to 750°C, more preferably in the range of from 20°C to 450°C, and feeding the heated first product stream into a second reactor to obtain a second product stream,

[0068] Therein, preferably the heat of the second product stream is used in (ii) as at least part of the heat from the chemical conversion process which is transferred to the heat transfer medium.

[0069] In case the process further comprises (ix) providing the first product stream obtained in (viii) as a stream comprising NH3 in a subsequent process for transferring heat to a stream comprising NH3, it is preferred that the first product stream is fed according to (ix) to a stream having a flow rate of from 350 to 20000 h. -1 In the range of 400 to 4000h, more preferably -1 In the second reactor, the gas hourly space velocity is within the range of 1:1.

[0070] Additionally and independently, it is preferred that the second product stream obtained in (ix) has a temperature in the range from 110 to 350°C, more preferably in the range from 160 to 250°C.

[0071] Additionally and independently, it is preferred that from 1 to 50 mol-%, more preferably from 5 to 25 mol-%, of the NH3 contained in the first product stream fed to the second reactor is converted into N2 and H2, based on 100 mol-% NH3 contained in the heated stream fed to the first reactor.

[0072] Additionally and independently, preferably, the method further comprises

[0073] (x) providing the second product stream obtained in (ix) as a stream comprising NH3 in a subsequent process for transferring heat to a stream comprising NH3 according to any one of the specific and preferred embodiments of the present invention, and heating the first product stream in (v) of said subsequent process to a temperature in the range from 250°C to 550°C, more preferably in the range from 290°C to 310°C, and feeding the heated second product stream into a third reactor to obtain a third product stream,

[0074] Therein, the heat of the third product stream is preferably used in (ii) as at least part of the heat from the chemical conversion process which is transferred to the heat transfer medium.

[0075] In case the process further comprises (x) providing the second product stream obtained in (ix) as a stream comprising NH3 in a subsequent process for transferring heat to a stream comprising NH3, it is preferred that the second product stream is fed according to (x) to a heat exchanger having a flow rate of from 400 to 20000 h. -1 In the range of 540 to 4000h, more preferably in the range of 540 to 4000h -1 In the third reactor with a gas hourly space velocity within the range of .

[0076] Additionally and independently, it is preferred that the third product stream obtained in (x) has a temperature in the range from 120 to 300°C, more preferably in the range from 170 to 235°C.

[0077] Additionally and independently, it is preferred that from 1 to 50 mol-%, more preferably from 5 to 25 mol-%, of the NH3 contained in the second product stream fed to the third reactor is converted into N2 and H2, based on 100 mol-% NH3 contained in the heated stream fed to the first reactor.

[0078] According to the present invention, it is preferred that the first reactor, the second reactor and the third reactor are independently of each other adiabatic reactors, isothermal reactors or a combination thereof.

[0079] Within the meaning of the present invention, an adiabatic or isothermal reactor is understood to be a reactor which operates close to a theoretical adiabatic or isothermal process.

[0080] Furthermore, it is preferred that the first reactor, the second reactor and the third reactor are independently tubular reactors.

[0081] Furthermore, it is preferred that the first reactor, the second reactor and the third reactor independently of each other have a diameter in the range from 0.5 to 5 m, more preferably in the range from 1.5 to 2.5 m, more preferably in the range from 1.9 to 2.1 m.

[0082] Furthermore, it is preferred that the first reactor, the second reactor and the third reactor independently of each other have a length ranging from 1.0 to 20.0 m, more preferably ranging from 2.0 to 13.0 m, more preferably ranging from 3.0 to 12.0 m.

[0083] According to the present invention, it is preferred that the heated stream obtained in (v) is used as fuel or co-fuel for combustion with oxygen to supply heat to the endothermic reaction.

[0084] Furthermore, it is preferred that the heated stream obtained in (v) is used as a feed stream for the NH3 reforming process.

[0085] The invention also relates to a method for transferring heat to a stream containing NH3, the method comprising

[0086] (1) transferring heat to a stream comprising NH3 according to any one of the specific and preferred embodiments of the present invention, wherein the initial stream has a temperature T0 and the obtained heated stream has a temperature T1, wherein T1>T0;

[0087] (2) Transferring heat to the NH3-containing stream obtained in (1) according to any one of the specific and preferred embodiments of the present invention, wherein the obtained heated stream has a temperature T2, wherein T2>T1.

[0088] According to the present invention, preferably, the method further comprises one or more subsequent steps

[0089] (N) transferring heat to the NH3-containing stream obtained in (N-1) according to any one of the specific and preferred embodiments of the present invention, wherein the obtained heated stream has a temperature T N , where T N >T N-1 ;

[0090] wherein N is 3, or 3 and 4, or 3 to 5, or 3 to 6, or 3 to 7, or 3 to 8, or 3 to 9, or 3 to 10, or 3 to 11, or 3 to 12, or 3 to 13, or 3 to 14, or 3 to 15, or 3 to 16, or 3 to 17, or 3 to 18, or 3 to 19, or 3 to 20.

[0091] In the context of the present invention, a method further comprising one or more sequential subsequent steps (N) comprises x additional steps, where x = N - 2. For example, a method wherein N is 3 further comprises one sequential subsequent step (3), i.e., after step (2). As another example, a method wherein N is 3 to 5 comprises three sequential subsequent steps (3), (4), and (5) after step (2).

[0092] The unit bar (absolute) refers to absolute pressure, where 1 bar is equal to 10 5 Pa.

[0093] The present invention is further illustrated by the following set of examples and combinations of examples derived from the dependencies and back-references shown. In particular, it should be noted that in each case where a series of examples is mentioned, for example, in the context of a term such as "a method as described in any one of Examples 1 to 4," each example in this series is intended to be clearly disclosed to the skilled person, i.e., the wording of this term should be understood by the skilled person as synonymous with "a method as described in any one of Examples 1, 2, 3, and 4." In addition, it is expressly noted that the following set of examples is not a set of claims that determines the scope of protection, but rather represents a suitable configuration portion of this specification relating to general and preferred aspects of the present invention.

[0094] 1. A method for transferring heat to a stream containing NH3, the method comprising:

[0095] (i) providing a stream comprising a heat transfer medium,

[0096] wherein the stream has a pressure in the range from 1 to 100 bar (absolute) and a temperature equal to or greater than 105° C.;

[0097] (ii) increasing the temperature of the stream provided in (i) by transferring heat from a chemical conversion process, from a physicochemical process, or from ambient heat, or from a combination of two or more thereof, to the heat transfer medium to obtain a stream having a temperature in the range of from 125° C. to 750° C.;

[0098] (iii) increasing the pressure of the stream obtained in (ii),

[0099] to obtain a compressed stream having a temperature in the range from 50° C. to 800° C.;

[0100] (iv) providing a stream comprising NH 3 , wherein the stream comprising NH 3 has a temperature in the range from -33° C. to 100° C.;

[0101] (v) heating the stream provided in (iv), wherein heating comprises transferring heat from the compressed stream obtained in (iii) to the stream provided in (iv) to obtain a heated stream comprising NH3, the heated stream having a temperature in the range from 25°C to 750°C;

[0102] (vi) expanding the compressed stream obtained in (v);

[0103] (vii) optionally recycling at least a portion of the stream obtained in (vi) to (i).

[0104] 2. The method of embodiment 1, wherein the heat transfer medium is selected from the group consisting of evaporating and condensing working fluids and supercritical working fluids, wherein preferably the heat transfer medium is water, wherein more preferably the heat transfer medium is steam.

[0105] 3. The method of embodiment 1 or 2, wherein the stream provided in (i) has a temperature equal to or greater than 150°C, preferably in the range of from 200°C to 550°C, more preferably in the range of from 250°C to 350°C.

[0106] 4. The method of any one of embodiments 1 to 3, wherein the stream provided in (i) has a pressure in the range of from 5 to 50 bar (absolute), more preferably in the range of from 10 to 40 bar (absolute), more preferably in the range of from 20 to 30.

[0107] 5. The method of any one of embodiments 1 to 4, wherein the stream provided in (i) comprises from 0 to 1 vol%, preferably from 0 to 0.1 vol%, more preferably from 0 to 0.01 vol% NH3.

[0108] 6. The method of any one of embodiments 1 to 5, wherein from 95 to 100% by volume, preferably from 99 to 100% by volume, more preferably from 99.9 to 100% by volume of the stream provided in (i) consists of the heat transfer medium.

[0109] 7. The method of any one of embodiments 1 to 6, wherein the heat transfer according to (ii) is performed using a heat exchanger.

[0110] 8. The method of any one of embodiments 1 to 7, wherein the ambient heat transferred according to (ii) is heat from the environment, preferably heat from one or more of air, water, soil, and solar radiation (including combinations of two or more thereof).

[0111] 9. The method of any one of embodiments 1 to 8, wherein the heat from the chemical conversion process transferred according to (ii) is obtained from an exothermic reaction, or wherein the heat from the chemical conversion process transferred according to (ii) is excess heat for conducting an autothermal reaction or an endothermic reaction.

[0112] 10. The method of embodiment 9, wherein the exothermic reaction comprises one or more of the following: methanol production, dimethyl ether production, NH3 production, ethylene epoxidation, sulfuric acid production, and selective oxidation of one or more of alkanes, alkenes, and alkynes, preferably selective oxidation of one or more of alkanes, alkenes, and alkynes to acrolein or acrylic acid.

[0113] 11. The method of embodiment 9, wherein the endothermic reaction comprises one or more of steam cracking, ethane dehydrogenation, propane dehydrogenation, butane dehydrogenation, steam reforming, dry reforming, styrene production, methanol reforming, dimethyl ether reforming, reverse water gas shift, alcohol dehydration, and NH3 reforming.

[0114] 12. The method of embodiment 9, wherein the autothermal reaction is selected from the group consisting of: autothermal reforming of natural gas and hydrocarbons (including partial oxidation (POx) of hydrocarbons), wherein the hydrocarbons are selected from (C1-C 10 )alkanes, more preferably (C1-C8)alkanes, more preferably (C1-C7)alkanes.

[0115] 13. The process of any one of embodiments 1 to 12, wherein the stream obtained in (ii) has a temperature in the range of from 25°C to 750°C, preferably in the range of from 100°C to 550°C, more preferably in the range of from 150°C to 300°C, more preferably in the range of from 180°C to 200°C.

[0116] 14. The method of any one of embodiments 1 to 13, wherein the heat from the physicochemical process transferred according to (ii) is obtained from an exothermic change of aggregate state of the compound or material, more preferably from condensation and solidification of the compound or material.

[0117] 15. The method of embodiment 14, wherein the heat from the physicochemical process transferred according to (ii) is obtained from vapor compression evaporation.

[0118] 16. The method of any one of embodiments 1 to 15, wherein in (ii), the heat transfer medium undergoes at least partial evaporation.

[0119] 17. The process of any one of embodiments 1 to 16, wherein a compressed stream having a pressure in the range of from 1 to 250 bar (absolute), preferably in the range of from 5 to 150 bar (absolute), more preferably in the range of from 10 to 100 bar (absolute), more preferably in the range of from 20 to 90 bar (absolute) is obtained according to (iii).

[0120] 18. The method of any one of embodiments 1 to 17, wherein increasing the pressure of the stream according to (iii) is performed using a compressor.

[0121] 19. The method of any one of embodiments 1 to 18, wherein the method provides a coefficient of performance (COP) greater than 1, preferably 1.1 to 4, more preferably 1.2 to 3, more preferably 1.2 to 2, more preferably 1.2 to 1.5.

[0122] 20. The method of any one of embodiments 1 to 19, wherein increasing the pressure of the stream according to (iii) is performed adiabatically.

[0123] 21. The process of any one of embodiments 1 to 20, wherein from 95 to 100 vol%, preferably from 99 to 100 vol%, more preferably from 99.9 to 100 vol% of the stream provided in (iv) consists of NH3.

[0124] 22. The method of any one of embodiments 1 to 21, wherein the stream provided in (iv) has a temperature in the range of from -33°C to 100°C, preferably in the range of from -15°C to 80°C, more preferably in the range of from 0°C to 60°C, more preferably in the range of from 15°C to 50°C, more preferably in the range of from 25°C to 40°C.

[0125] 23. The method of any one of embodiments 1 to 22, wherein the stream provided in (iv) has a pressure in the range of from 1 to 100 bar (absolute), preferably in the range of from 20 to 35 bar (absolute).

[0126] 24. The method of any one of embodiments 1 to 23, wherein the stream provided in (iv) has a flow rate of from 200 to 20,000 h. -1 In the range of, preferably from 2,000 to 8,000h -1 Weight hourly space velocity in the range.

[0127] 25. The method of any one of embodiments 1 to 24, wherein the heating according to (v) comprises at least partially converting NH3 into N2 and H2, wherein the heating according to (v) preferably comprises converting from 1 to 100 vol%, more preferably from 15 to 50 vol% of NH3.

[0128] 26. The process of any one of embodiments 1 to 25, wherein a compressed stream having a temperature in the range of from 200°C to 750°C, preferably in the range of from 300°C to 550°C is obtained according to (v).

[0129] 27. The method of any one of embodiments 1 to 26, wherein a compressed stream having a pressure in the range from 1 to 100 bar (absolute), preferably in the range from 20 to 35 bar (absolute) is obtained according to (v).

[0130] 28. The method of any one of embodiments 1 to 27, wherein the compressed stream obtained in (v) has the same pressure as the compressed stream obtained in (iii).

[0131] 29. The method of any one of embodiments 1 to 28, wherein the heating according to (v) is performed using a heat exchanger, wherein the heat exchanger is preferably the reactor containing the stream provided in (iv), more preferably the wall of the reactor containing the stream provided in (iv).

[0132] 30. The process of any one of embodiments 1 to 29, wherein a stream comprising NH3 having a temperature in the range of from 250°C to 750°C, preferably in the range of from 290°C to 310°C is obtained according to (v).

[0133] 31. The process of any one of embodiments 1 to 30, wherein a stream comprising NH3 is obtained according to (v) having a pressure in the range from 1 to 100 bar (absolute), preferably in the range from 10 to 40 bar (absolute).

[0134] 32. The method of any one of embodiments 1 to 31, wherein the expansion according to (vi) is performed using a thermal expansion valve.

[0135] 33. The method of any one of embodiments 1 to 32, wherein the expanded stream obtained in (v) has the same pressure and temperature as the stream comprising the heat transfer medium provided in (i).

[0136] 34. The method of any one of embodiments 1 to 33, wherein expanding the compressed stream according to (vi) is performed adiabatically.

[0137] 35. The process of any one of embodiments 1 to 34, wherein from 1 to 100% by volume, preferably from 50 to 100% by volume, of the stream obtained in (vi) is recycled to (i) according to (vii).

[0138] 36. The process of any one of embodiments 1 to 35, wherein the stream obtained in (vi) is fully recycled to (i) according to (vii).

[0139] 37. The method of embodiment 36, wherein steps (i) to (vii) are performed in a closed system in which a stream comprising a heat transfer medium is circulated.

[0140] 38. The method of any one of embodiments 1 to 37, further comprising

[0141] (viii) feeding the heated stream comprising NH3 obtained in (v) into a first reactor to obtain a first product stream, wherein the heat of the first product stream is preferably used in (ii) as at least part of the heat from the chemical conversion process that is transferred to the heat transfer medium.

[0142] 39. The process of embodiment 38, wherein the heated stream obtained in (v) is fed to a first reactor having a temperature in the range of from 200°C to 750°C, preferably in the range of from 250°C to 550°C.

[0143] 40. The method of embodiment 38 or 39, wherein the heated stream obtained in (v) is heated at a temperature of from 200 to 20,000 h. -1 In the range of, preferably from 400 to 4,000h -1 The gas hourly space velocity within the range is fed into the first reactor.

[0144] 41. The process of any one of embodiments 38 to 40, wherein the first product stream obtained in (viii) has a temperature in the range of from 110°C to 350°C, preferably in the range of from 160°C to 250°C.

[0145] 42. The method of any one of embodiments 38 to 41, wherein from 1 to 75 mol-%, more preferably from 5 to 45 mol-%, of the NH3 contained in the heated stream fed to the first reactor is converted into N2 and H2, based on 100 mol-% NH3 contained in the heated stream fed to the first reactor.

[0146] 43. The method of any one of embodiments 38 to 42, further comprising

[0147] (ix) providing the first product stream obtained in (viii) as a stream comprising NH3 in a subsequent process for transferring heat to a stream comprising NH3 according to any one of embodiments 1 to 42, 57 and 58, and heating the first product stream in (v) of the subsequent process to a temperature in the range of from 200°C to 750°C, preferably in the range of from 20°C to 450°C, and feeding the heated first product stream to a second reactor to obtain a second product stream,

[0148] Therein, preferably the heat of the second product stream is used in (ii) as at least part of the heat from the chemical conversion process which is transferred to the heat transfer medium.

[0149] 44. The method of embodiment 43, wherein the first product stream is fed to a reactor having a temperature of from 350 to 20,000 h according to (ix). -1 In the range of 400 to 4000h, preferably -1 In the second reactor, the gas hourly space velocity is within the range of 1:1.

[0150] 45. The process of embodiment 43 or 44, wherein the second product stream obtained in (ix) has a temperature in the range of from 110°C to 350°C, preferably in the range of from 160°C to 250°C.

[0151] 46. ​​A method as described in any of embodiments 43 to 45, wherein from 1 to 50 mol-%, preferably from 5 to 25 mol-%, of NH3 contained in the first product stream fed to the second reactor is converted into N2 and H2 based on 100 mol-% NH3 contained in the heated stream fed to the first reactor.

[0152] 47. The method of any one of embodiments 43 to 46, further comprising

[0153] (x) providing the second product stream obtained in (ix) as a stream comprising NH3 in a subsequent process for transferring heat to a stream comprising NH3 according to any one of embodiments 1 to 42, 57 and 58, and heating the first product stream in (v) of said subsequent process to a temperature in the range of from 250°C to 550°C, preferably in the range of from 290°C to 310°C, and feeding the heated second product stream into a third reactor to obtain a third product stream,

[0154] Therein, the heat of the third product stream is preferably used in (ii) as at least part of the heat from the chemical conversion process which is transferred to the heat transfer medium.

[0155] 48. The method of embodiment 47, wherein the second product stream is fed to a reactor having a temperature of from 400 to 20,000 h. -1 range, preferably from 540 to 4000h -1 In the third reactor with a gas hourly space velocity within the range of .

[0156] 49. The process of any one of embodiments 47 or 48, wherein the third product stream obtained in (x) has a temperature in the range of from 120°C to 300°C, preferably in the range of from 170°C to 235°C.

[0157] 50. A method as described in any of embodiments 47 to 49, wherein from 1 to 50 mol-%, preferably from 5 to 25 mol-%, of NH3 contained in the second product stream fed to the third reactor is converted into N2 and H2 based on 100 mol-% NH3 contained in the heated stream fed to the first reactor.

[0158] 51. The method of any one of embodiments 38 to 50, wherein the first reactor, the second reactor, and the third reactor are independently adiabatic reactors, isothermal reactors, or a combination thereof.

[0159] 52. The method of any one of embodiments 38 to 51, wherein the first reactor, the second reactor, and the third reactor are independently tubular reactors.

[0160] 53. The method of any one of embodiments 38 to 52, wherein the first reactor, the second reactor, and the third reactor independently of one another have a diameter in the range of from 0.5 to 5 m, preferably in the range of from 1.5 to 2.5 m, more preferably in the range of from 1.9 to 2.1 m.

[0161] 54. The method of any one of embodiments 38 to 53, wherein the first reactor, the second reactor, and the third reactor independently of one another have a length in the range of from 1.0 to 20.0 m, preferably in the range of from 2.0 to 13.0 m, more preferably in the range of from 3 to 12 m.

[0162] 55. The method of any one of embodiments 1 to 54, wherein the heated stream obtained in (v) is used as a fuel or co-fuel for combustion with oxygen to provide heat to the endothermic reaction.

[0163] 56. The method of any one of embodiments 1 to 55, wherein the heated stream obtained in (v) is used as a feed stream for an NH3 reforming process.

[0164] 57. A method for transferring heat to a stream containing NH3, the method comprising

[0165] (1) transferring heat to a stream comprising NH3 according to any one of embodiments 1 to 42, wherein the initial stream has a temperature T0 and the obtained heated stream has a temperature T1, wherein T1>T0;

[0166] (2) Transferring heat to the NH 3 -containing stream obtained in (1) according to any one of embodiments 1 to 42, wherein the obtained heated stream has a temperature T2, wherein T2>T1.

[0167] 58. The method of embodiment 57, further comprising one or more subsequent steps

[0168] (N) transferring heat to the NH3-containing stream obtained in (N-1) according to any one of embodiments 1 to 42, wherein the obtained heated stream has a temperature T N , where T N >T N-1 ;

[0169] wherein N is 3, or 3 and 4, or 3 to 5, or 3 to 6, or 3 to 7, or 3 to 8, or 3 to 9, or 3 to 10, or 3 to 11, or 3 to 12, or 3 to 13, or 3 to 14, or 3 to 15, or 3 to 16, or 3 to 17, or 3 to 18, or 3 to 19, or 3 to 20.

[0170] The present invention is further illustrated by the following Reference Examples, Examples and Comparative Examples.

[0171] Examples

[0172] The following examples were simulated using conventional software.

[0173] Example 1: NH3 vaporization and preheating with a coupled heat pump

[0174] The heat pump's hot outlet is used to vaporize and preheat the NH3-containing stream for further processing. Table 1 below shows the associated power consumption values. For the processing of NH3-containing streams without a subsequent NH3 reforming step, coefficient of performance (COP) values ​​of 4.0 or 1.3 (thus well above 1) can be achieved. This depends on whether the heat pump is used only for the evaporation step or also for preheating.

[0175] Table 1:

[0176] Data for preheating an NH3-containing stream using a heat pump for heating.

[0177] evaporation Heating to 250℃ <![CDATA[NH3 flow]]> 10t / h 10t / h <![CDATA[Power consumption of heat flux / heat pump for NH3 evaporation]]> 3.8MW / 1.0MW --- Heating from 20°C to 250°C / Power consumption of heat pump --- 1.3MW / 1.0MW COP 4.0 1.3

[0178] Example 2: NH3 reforming reaction in an adiabatic reactor coupled to a heat pump

[0179] The preheated NH3-containing gas stream produced according to Example 1 was used in an NH3 reforming process in an adiabatic reactor. In this case, the inlet temperature was fixed at 300°C. The NH3-containing gas flow was set at 10 t / h as a reference scenario, and the adiabatic reactor had a fixed geometry of 2 m diameter and 10 m length. Table 2 shows the inlet and outlet temperatures, NH3 conversion, and greenhouse gas emission values. Figure 1 shows the conversion, temperature, and equilibrium values.

[0180] Table 2:

[0181] Temperature, NH3 conversion and GHSV for the adiabatic reactor concept

[0182] Inlet temperature, °C Outlet temperature, ℃ Conversion rate, % <![CDATA[GHSV,h -1 ]]> Adiabatic reactor 300 167.7 11.4 419

[0183] Example 3: NH3 reforming reaction in adiabatic reactor cascade coupled with a heat pump

[0184] The preheated NH3-containing gas stream produced according to Example 1 was used in an NH3 reforming process using a cascade of adiabatic reactors. In this case, the inlet temperature of each reactor was fixed at 300°C. In the first adiabatic reactor, the NH3-containing gas stream was set to 10 t / h as a reference scenario. The outlet stream of the first adiabatic reactor was reheated to 300°C and fed to the second adiabatic reactor. The outlet stream of the second adiabatic reactor was reheated to 300°C and fed to the third adiabatic reactor. Each adiabatic reactor had a fixed geometry of 2 m in diameter and 10 m in length. Table 3 shows the inlet and outlet temperatures, NH3 conversion and GHSV. Figure 2 shows the conversion, temperature and equilibrium values.

[0185] Table 3:

[0186] Temperature, NH3 conversion and GHSV of three adiabatic reactors in series

[0187] Inlet temperature, °C Outlet temperature, °C Conversion rate, % <![CDATA[GHSV,h -1 ]]> 1st adiabatic reactor 300 167.7 11.4 419 Second adiabatic reactor 300 180.6 22.1* 511 3rd adiabatic reactor 300 189.1 32.4* 554

[0188] (*)Grand total

[0189] Example 4: NH3 reforming reaction in a quasi-isothermal reactor coupled with a heat pump

[0190] The preheated NH3-containing gas stream produced according to Example 1 was used for the NH3 reforming process within a quasi-isothermal reactor concept. Thus, the NH3-containing gas stream with steam at a temperature of 300°C served as the heat source for the endothermic NH3 reforming process. Table 4 shows the corresponding conversion values ​​for NH3 and the inlet / outlet temperatures. The reactor had a fixed geometry of 2 m in diameter and 10 m in length. The heat flux of the quasi-isothermal process concept was adjusted to 170 W / m 2 / K.

[0191] Table 4:

[0192] Temperature, NH3 conversion and GHSV of quasi-isothermal reactor

[0193] Inlet temperature, °C Outlet temperature, °C Conversion rate, % <![CDATA[GHSV,h -1 ]]> Quasi-isothermal reactor 300 216.1 18.3 419

[0194] Example 5: NH3 reforming reaction using two adiabatic reactors and a quasi-isothermal reactor in series coupled with a heat pump

[0195] a) Reactor settings and NH3 conversion

[0196] The preheated NH3-containing gas stream produced according to Example 1 was used in an NH3 reforming process using a cascade of two adiabatic reactors followed by a quasi-isothermal reactor. In this case, the inlet temperature of each reactor was fixed at 300°C. In the first adiabatic reactor, the NH3-containing gas stream was set to 10 t / h as a reference scenario. The outlet of the first adiabatic reactor was heated again to 300°C and fed into the second adiabatic reactor. All reactors had a fixed geometry of 2 m in diameter and 10 m in length. The heat flux for the quasi-isothermal reactor was adjusted to 170 W / m 2 / K. Table 5 shows the inlet and outlet temperatures, NH3 conversion and GHSV. Figure 4 shows the conversion, temperature and equilibrium values.

[0197] Table 5:

[0198] Temperature, NH3 conversion and GHSV of two adiabatic reactors and one quasi-isothermal reactor in series

[0199] Inlet temperature, °C Outlet temperature, °C Conversion rate, % <![CDATA[GHSV,h -1 ]]> 1st adiabatic reactor 300 167.7 11.4 419 Second adiabatic reactor 300 180.6 22.1* 511 3rd Quasi-Isothermal Reactor 300 227.4 37.6* 576

[0200] (*)Grand total

[0201] b) COP value of the heat pump system with a reactor inlet at 300°C

[0202] The impact of the heat pump integration according to Example 5 was calculated. Table 6 shows the energy values ​​that ultimately lead to a COP value of 1.2. This means that the NH3 reforming process is 20% more efficient when the heat pump concept is applied compared to using electricity directly to heat the reactor.

[0203] Table 6:

[0204] COP values ​​of heat pump systems coupled with dedicated NH3 conversion scenarios

[0205]

[0206]

[0207] References:

[0208] -DE 2951188 A1

[0209] -DE 3209642 A1

[0210] - V. Singh et al., “Investigation of new mechanical heat pump systems for heat upgrading applications,” Int. J. Energy Ress., 2018, 42, 3078-3090

Claims

1. A method for transferring heat to a stream containing NH3, the method comprising: (i) providing a stream comprising a heat transfer medium, wherein the stream has a pressure in the range from 1 to 100 bar (absolute) and a temperature equal to or greater than 105°C; (ii) increasing the temperature of the stream provided in (i) by transferring heat from a chemical conversion process, from a physicochemical process, or from ambient heat, or from a combination of two or more thereof, to the heat transfer medium to obtain a stream having a temperature in the range from 125° C. to 750° C.; (iii) increasing the pressure of the stream obtained in (ii), to obtain a compressed stream having a temperature in the range from 50° C. to 800° C.; (iv) providing a stream comprising NH3, wherein the stream comprising NH3 has a temperature in the range from -33°C to 100°C; (v) heating the stream provided in (iv), wherein heating comprises transferring heat from the compressed stream obtained in (iii) to the stream provided in (iv) to obtain a heated stream comprising NH3, the heated stream having a temperature in the range from 25°C to 750°C; (vi) expanding the compressed stream obtained in (v); (vii) optionally recycling at least a portion of the stream obtained in (vi) to (i).

2. The method of claim 1, wherein: The heat transfer medium is selected from the group consisting of evaporating and condensing working fluids and supercritical working fluids.

3. The method according to claim 1 or 2, wherein: The heat transfer according to (ii) is carried out using a heat exchanger.

4. The method according to any one of claims 1 to 3, wherein: The ambient heat transferred according to (ii) is heat from the environment.

5. The method according to any one of claims 1 to 4, wherein: The heat from the chemical conversion process transferred according to (ii) is obtained from an exothermic reaction, or wherein the heat from the chemical conversion process transferred according to (ii) is excess heat for carrying out an autothermal reaction or an endothermic reaction.

6. The method according to any one of claims 1 to 5, wherein: The heat from the physicochemical process transferred according to (ii) is obtained from the exothermic change of the aggregate state of the compound or material.

7. The method of claim 6, wherein: The heat from the physicochemical process transferred according to (ii) is obtained from the vapor compression evaporation.

8. The method according to any one of claims 1 to 7, wherein: Increasing the pressure of the stream according to (iii) is performed using a compressor.

9. The method according to any one of claims 1 to 8, wherein: This method provides a coefficient of performance (COP) greater than 1.

10. The method according to any one of claims 1 to 9, wherein: The increasing of the pressure of the stream according to (iii) is performed adiabatically.

11. The method according to any one of claims 1 to 10, wherein: The expansion of the compressed stream according to (vi) is performed adiabatically.

12. The method according to any one of claims 1 to 11, wherein: The method further comprises (viii) feeding the heated stream comprising NH3 obtained in (v) into a first reactor to obtain a first product stream.

13. The method of claim 12, wherein: The method further comprises (ix) providing the first product stream obtained in (viii) as the NH3-containing stream in a subsequent process for transferring heat to a stream containing NH3 according to any one of claims 1 to 11 and 15, and heating the first product stream to a temperature in the range from 200°C to 750°C in (v) of the subsequent process, and feeding the heated first product stream into a second reactor to obtain a second product stream.

14. The method of claim 13, wherein: The method further comprises (x) providing the second product stream obtained in (ix) as the NH3-containing stream in a subsequent process for transferring heat to a stream containing NH3 according to any one of claims 1 to 11 and 15, and heating the first product stream to a temperature in the range from 250°C to 550°C in (v) of the subsequent process and feeding the heated second product stream into a third reactor to obtain a third product stream.

15. A method for transferring heat to a stream containing NH3, the method comprising (1) transferring heat to a stream comprising NH3 according to any one of claims 1 to 11, wherein the initial stream has a temperature T0 and the obtained heated stream has a temperature T1, wherein T1>T0; (2) Transferring heat to the NH 3 -containing stream obtained in (1) according to any one of claims 1 to 42, wherein the obtained heated stream has a temperature T2, wherein T2>T1.

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