阅读说明：本技术 反应器组件和执行反应的方法 (Reactor assembly and method of performing a reaction ) 是由 R·F·郑 R·S·韦根 P·H·亨博 D·D·考德威尔 R·B·戴维 于 2020-03-20 设计创作，主要内容包括：本发明提供了反应器,其可以包括第一组流体通道和被定向成与第一组流体通道热接触的第二组流体通道。还可以提供反应器组件,其中第一组流体通道或第二组流体通道中的任一组或两组的通道都是非线性的。其他实施方式提供了第一组流体通道中的至少一个流体通道与第二组流体通道中的多个其他通道热接触。还提供了反应器组件,其可包括：限定至少一个非线性通道的第一组流体通道,所述至少一个非线性通道具有正函数；以及限定至少另一个非线性通道的第二组流体通道,所述至少另一个非线性通道具有相对于第一组流体通道的一个非线性通道的正函数的负函数。提供了用于在反应器上分配能量的方法。所述方法可包括经由第一组流体通道将反应物输送到第二组流体通道,并且使第一组流体通道中的至少一个流体通道与第二组流体通道中的至少两个流体通道热接合。(The invention provides a reactor that may include a first set of fluid channels and a second set of fluid channels oriented in thermal contact with the first set of fluid channels. A reactor assembly may also be provided in which the channels of either or both of the first or second sets of fluid channels are non-linear. Other embodiments provide that at least one fluidic channel of the first set of fluidic channels is in thermal contact with a plurality of other channels of the second set of fluidic channels. Also provided is a reactor assembly, which may include: a first set of fluidic channels defining at least one non-linear channel, the at least one non-linear channel having a positive function; and a second set of fluid channels defining at least one other non-linear channel having a negative function relative to the positive function of one non-linear channel of the first set of fluid channels. A method for distributing energy over a reactor is provided. The method may include delivering a reactant to the second set of fluid channels via the first set of fluid channels, and thermally joining at least one fluid channel of the first set of fluid channels with at least two fluid channels of the second set of fluid channels.)

1. A reactor, comprising:

a first set of fluid channels;

a second set of fluid channels oriented in thermal contact with the first set of fluid channels; and is

Wherein the channels of either the first set of fluid channels or the second set of fluid channels are non-linear.

2. The reactor of claim 1, wherein the first set of channels define microchannels.

3. The reactor of claim 1, wherein the first set of channels defines a center channel.

4. The reactor of claim 1, wherein the first set of channels and the second set of channels define microchannels.

5. The reactor of claim 1, wherein the first set of channels and the second set of channels define a center channel.

6. The reactor of claim 1, wherein both the first set of fluid channels and the second set of fluid channels are non-linear.

7. The reactor of claim 1, wherein each of the sets of fluid passages extends from the hub of the reactor and to the rim of the reactor.

8. The reactor of claim 7 wherein each channel of said first set of fluid channels is in fluid communication with each channel of said second set of fluid channels at said rim of said reactor.

9. The reactor of claim 1, wherein each channel of either the first set of channels or the second set of channels comprises a partition member.

10. The reactor of claim 9 wherein said dividing member extends to form a pair of fluid passageways.

11. The reactor of claim 10 wherein each channel of both of the first set of channels and the second set of channels comprises a partition member.

12. The reactor of claim 1 wherein the other of said first set of fluid channels or said second set of fluid channels is linear.

13. The reactor of claim 1 further comprising a member separating said first set of fluid channels from said second set of fluid channels.

14. The reactor of claim 13 wherein said member is thermally conductive.

15. The reactor of claim 13, wherein the member defines, in at least one cross-section, a bottom plate of one of the sets of fluid channels and a top plate of another of the sets of fluid channels.

16. A stacked reactor, comprising:

a first set of fluid channels;

a second set of fluid channels stacked on and oriented in thermal contact with the first set of fluid channels; and is

Wherein at least one channel of the first set of fluid channels is in thermal contact with a plurality of other channels of the second set of fluid channels.

17. The reactor of claim 16, wherein the first set of channels define microchannels.

18. The reactor of claim 16, wherein the first set of channels defines a center channel.

19. The reactor of claim 16, wherein the first set of channels and the second set of channels define microchannels.

20. The reactor of claim 16 wherein said first set of channels and said second set of channels define a center channel.

21. The reactor of claim 16 wherein one channel of said first set of fluid channels is in thermal contact with at least two channels of the other channels of said second set of fluid channels.

22. The reactor of claim 16 wherein said one of said first set of fluid channels is in thermal contact with 2 to 14 of said other channels in said second set of fluid channels.

23. The reactor of claim 16, wherein at least one fluid channel of said first set of fluid channels is in fluid communication with at least one fluid channel of said plurality of other fluid channels of said second set of fluid channels.

24. The reactor of claim 23 wherein each channel of said first set of fluid channels is in fluid communication with each channel of said second set of fluid channels.

25. The reactor of claim 16, wherein one of the sets of fluid channels is stacked on another of the sets of fluid channels in at least one cross-section.

26. A reactor, comprising:

a first set of fluid channels defining at least one non-linear channel having a shape defined by a positive mathematical function; and

a second set of fluid channels defining at least one other non-linear channel having a shape defined by a negative mathematical function of the positive mathematical function relative to the one non-linear channel of the first set of fluid channels.

27. The reactor of claim 26, wherein the first set of channels define microchannels.

28. The reactor of claim 26, wherein said first set of channels defines a center channel.

29. The reactor of claim 26, wherein the first set of channels and the second set of channels define microchannels.

30. The reactor of claim 26 wherein said first set of channels and said second set of channels define a center channel.

31. The reactor of claim 26 wherein the absolute value of said mathematical function of said one channel is equal to the absolute value of said mathematical function of the other channel.

32. The reactor of claim 26, wherein said first set of fluid channels defines a plurality of non-linear channels having the same positive mathematical function; and the second set of fluid channels defines a plurality of non-linear channels having the same negative mathematical function relative to the positive mathematical function of the plurality of non-linear channels of the first set of fluid channels.

33. The reactor of claim 32, wherein an absolute value of said mathematical function of said plurality of non-linear channels of said first set of fluid channels is equal to an absolute value of said mathematical function of said plurality of non-linear channels of said second set of fluid channels.

34. The reactor of claim 26, wherein each of the individual fluid channels of the first set of fluid channels defines a non-linear channel having the positive mathematical function; and each of the respective fluidic channels of the second set of fluidic channels defines a non-linear channel having the negative mathematical function relative to the positive mathematical function of the respective non-linear channel of the first set of fluidic channels.

35. The reactor of claim 34 wherein the absolute value of said mathematical function for said each non-linear channel in said first set of fluid channels is equal to the absolute value of said mathematical function for said each non-linear channel in said second set of fluid channels.

36. A method for distributing energy across a reactor, the method comprising:

delivering reactants to the second set of fluid channels via the first set of fluid channels; and

thermally joining at least one fluid channel of the first set of fluid channels with at least two fluid channels of the second set of fluid channels.

37. The method of claim 36, further comprising performing an endothermic reaction within one of the sets of fluid channels.

38. The method of claim 37, further comprising promoting the endothermic reaction with solar energy.

39. The method of claim 37, further comprising promoting the endothermic reaction with a catalyst.

Technical Field

The present disclosure relates to reactor assemblies and methods for performing reactions. Embodiments of the present disclosure relate to performing endothermic reactions. Embodiments of the present invention may also utilize solar or other heat sources to drive endothermic reactions.

Background

In the case of hydrogen production, current commercial technologies include conventional steam methane reforming in systems that combust a portion of the product stream to drive the endothermic reaction, and water electrolysis where the energy for the electrochemical reaction typically comes from the power grid. Solar thermochemical production of hydrogen from natural gas or other sources of methane can have the advantage of higher overall energy efficiency and reduced carbon emissions compared to conventional steam methane reforming and water electrolysis using grid power.

Reactor systems have been designed for steam reforming of methane and other hydrocarbons using concentrated solar energy. Reactor assemblies and methods have been provided, including U.S. patent No. 9,950,305 entitled "Solar thermal Processing System and Method" published 24.4.2018 and U.S. patent application serial No. 15/950,068 entitled "Solar thermal Processing System and Method" filed 10.4.2018, each of which is incorporated herein by reference in its entirety.

Disclosure of Invention

The invention provides a reactor that may include a first set of fluid channels and a second set of fluid channels oriented in thermal contact with the first set of fluid channels. The channels of either or both sets of fluid channels may be non-linear.

Also provided are stacked reactor components that may include a first set of fluid channels and a second set of fluid channels in a stacked configuration, wherein the fluid channels are oriented in thermal contact with each other and at least one fluid channel of the first set of fluid channels is in thermal contact with a plurality of other channels of the second set of fluid channels.

Also provided is a reactor assembly, which may include: a first set of fluid channels defining at least one non-linear channel having a shape defined by a positive mathematical function; and a second set of fluid channels defining at least one other non-linear channel having a shape defined by a negative mathematical function relative to a positive mathematical function of one non-linear channel of the first set of fluid channels.

A method for distributing energy over a reactor is provided. The method may include delivering a reactant to the second set of fluid channels via the first set of fluid channels, and thermally joining at least one fluid channel of the first set of fluid channels with at least two fluid channels of the second set of fluid channels.

Embodiments of the present disclosure may utilize thermal energy to promote or drive endothermic reactions in at least one of the sets of fluid channels. In particular embodiments, heat for the channels may be provided from a variety of sources, including electrical heating, exothermic chemical processes, and/or solar energy. The reactor and/or process may provide high temperature endothermic reactions such as methane steam reforming or reverse water gas shift, where the heat of reaction is provided primarily by solar energy. The reactors and/or methods of the present disclosure have application in the generation of syngas, which can be a precursor for the production of many chemicals, including hydrogen that can be used in refineries, for fuel cells, including fuel cell vehicles, and for other chemical processing applications.

The reactor assembly and/or method of the present disclosure may have two sets of helical fluid channels that may be separated by thin members and arranged in opposite helical directions to form a cross-flow pattern, a counter-flow pattern, or a counter-cross-flow pattern. Each group may be an array of repeating nonlinear elements defining one or more channels of a spiral flow path. The axes of symmetry of the two sets of channels may coincide at the hub. Although the repeating unit of each fluid channel may be the same or different, according to exemplary embodiments, the repeating unit may be different. The nonlinear fluid channels forming the repeating units of the array may be derived from a general curve of a helical nature, the curve being planar or three-dimensional. While many types of spiral curves can be used, archimedes and log spirals and their three dimensional derivatives are particularly relevant.

The integration of non-linear fluid channels and/or non-linear counter-flow channels may provide two benefits that translate into performance and economic advantages. First, the combination can provide thermal diffusion that reduces the severity of hot spots and thermal stresses, warms cold spots, and improves reactor life, as described below. Second, the combination may allow for the recovery of thermal energy (sensible heat) from the product stream to provide additional heat for the reaction. This can reduce the amount of solar energy required for a given amount of reaction and thus make the reactor system more efficient, higher productivity and lower cost.

Drawings

Embodiments of the present disclosure are described below with reference to the drawings.

Fig. 1 is a cross-sectional view of a reactor assembly according to an embodiment of the present disclosure.

Fig. 2 is a view of a set of channels of a reactor assembly according to an embodiment of the present disclosure.

Fig. 3 depicts two sets of reactor channels in a stacked configuration according to embodiments of the present disclosure.

Fig. 4 depicts two sets of reactor channels in a stacked configuration according to embodiments of the present disclosure.

Fig. 5A-5D are partial and complete configurations of reactor assemblies according to embodiments of the present disclosure.

Fig. 6 is a view of a configuration and an entire reactor within a range of (r, θ) coordinates according to an embodiment of the present disclosure.

Fig. 7A is a diagrammatic view of a reactor shown with portions cut away according to an embodiment of the present disclosure.

FIG. 7B is a diagram showing a reactor with one fluidic channel of a first set of fluidic channels in thermal contact with a plurality of fluidic channels of a second set of fluidic channels.

Fig. 8 is a reaction schematic according to an embodiment of the present disclosure.

Fig. 9 is a graphical representation of heat flux distribution data according to an embodiment of the present disclosure.

10A-10C are graphical representations of heat and stress distribution data according to embodiments of the present disclosure.

11A-11C are graphical representations of heat and stress distribution data according to embodiments of the present disclosure.

Fig. 12 is reaction data according to embodiments of the present disclosure.

Fig. 13 is reaction data according to embodiments of the present disclosure.

Detailed Description

It has been recognized that for practical solar concentrators, hot spots may exist at the reactor surface due to imperfections in the solar concentrator optics. Due to reactor metallurgical limitations, hot spots or local points of high solar radiation flux may limit the maximum total operating flux. Hot spots or other thermal gradients may also cause large thermal stresses in the reactor, which may lead to a shortened thermal cycle life due to low cycle fatigue. Thus, temperature differences associated with thermal gradients may result in high operating and/or capital costs and failures of the reactor system, resulting in reduced life.

The present invention will be described with reference to fig. 1-13. Referring first to fig. 1, a reactor 10 is shown according to a cross-section that includes a first set of fluid channels 12 in a stacked configuration over a second set of fluid channels 14. These fluid channels may be in thermal contact with each other via member 16. According to an exemplary embodiment, one or both of these sets of channels may include a non-linear fluid channel. According to other embodiments, one channel of the first set of fluid channels may be in thermal contact with a plurality of other channels of the second set of fluid channels. As shown in fig. 1, the reactor 10 may include a reactant flow to a first set of fluid channels that traverses the length of the member 16, then passes through the fluid pathway to a second set of fluid channels 14, and then exits the reactor after traversing the member 16.

Referring next to fig. 2, one example of a non-linear channel 20 is shown. The non-linear channel 20 may extend from the hub 22 to the rim 24 of the reactor, and the non-linear channel 20 may have a partition member 28 therein. The nonlinear channel 20 in combination with the partition member 28 may form, for example, a pair of fluid passages 30. The channel may be a microchannel or a mesochannel (mesochannel). The microchannels may have any length in the bulk flow direction and have a dimension (e.g., width) that is typically in the heat and/or mass transport direction and is greater than or equal to 1 micron and less than or equal to 1 millimeter. The mesochannel can have any length in the bulk flow direction and have a dimension (e.g., width) that is typically in the heat and/or mass transport direction and is greater than 1 millimeter and less than or equal to 1 centimeter.

Referring next to fig. 3, according to an exemplary embodiment of the invention, a non-linear channel 20 of one set of fluid channels may be associated with another set of linear fluid channels 26, and according to an exemplary embodiment, the channels may be stacked on top of each other.

Referring next to fig. 4, a pair of non-linear channels 20 and 40 is shown according to one configuration, providing fluid communication of the fluid channels 20 and 40 at 42. As shown, both channels 20 and 40 are non-linear. As shown in fig. 5A-5D, the non-linear channels 20 and 40 may be associated to form at least a portion of the reactor assembly 50, with the channels extending from the hub 22 and to the rim 24 of the assembly 50. Within each of these channels may be a partition member 58. The partition member 58 may extend toward the rim 24 to form a pair of fluid conduits. According to an exemplary embodiment, there may be a plurality of non-linear channels 52 and a plurality of non-linear channels 54, which may form a portion of the reactor 50, or in the case of fig. 5D, the entirety of the reactor. According to an exemplary embodiment, this may be considered a spiral channel design.

Referring next to fig. 6, sets of non-linear channels are shown extending from the hub 22 to the rim 24 of the reactor. These channels are shown aligned along an exemplary polar coordinate system 110, where the shape of the non-linear channel 60 can be considered to have a positive mathematical function with respect to the coordinate system, and the shape of the non-linear channel 80 can be considered to have a negative mathematical function with respect to the coordinate system.

The mathematical function defining the shape and direction of the channel can be represented by the general equation θ ═ f (r) with reference to the polar coordinate system 110 in fig. 6 having coordinates (r, θ), where f is an arbitrary function defining a particular curvature. For example, archimedean spirals and similar curves are represented by θ ═ ((r-b)/a)^cGiving out; the logarithmic spiral curve is given by θ ═ (lnr-lna)/b; a straight line is given by θ ═ d, where a, b, c, and d are parameters of arbitrary constants. For positive data with respect to polar coordinate system 110The set of non-linear channels 60 described by the function θ ═ f (r), the corresponding set of channels 80 can be described by the associated negative function defined by θ ═ f (r). More generally, the positive function θ ═ f can be passed₁(r) to define a set of non-linear channels, and may be defined by a negative function θ ═ f₂(r) to define another set of non-linear channels, wherein the mathematical function f₁And f₂May be the same or different. Furthermore, the mathematical function describing the shape of the non-linear channel may be essentially a three-dimensional spatial curve, in which case, without loss of generality, the general function θ ═ f (r, z) with reference to the cylindrical coordinate system (r, θ, z) may replace θ ═ f (r) in the preceding discussion.

According to an exemplary embodiment, the non-linear mathematical functions of the shapes of the fluid channels 60 and 80, when taken as absolute values, may be equal to each other, and thus have mirror images of each other. According to other embodiments, the fluid channels may not be mirror images of each other, but may still be configured as a reverse spiral. According to an exemplary embodiment, the reactor may include a plurality of non-linear fluid channels having the same positive function and a plurality of non-linear channels having the same negative function. The reactor may comprise the entirety of one set of non-linear channels having a positive function and another set of non-linear channels having a negative function. According to an exemplary embodiment, and referring to fig. 7A, a reactor 200 is shown that includes an inlet 202 and an outlet 204. Reactor 200 may include a first set of fluid channels 212 and a second set of fluid channels 214 connected, for example, at fluid pathway 230. In addition to the passages 230, there may be members 216 between each set of fluid channels 214 and 212. The member may be a thermally conductive member that may also form a top plate for the first set of fluid channels 212 and a bottom plate for the second set of fluid channels 214. According to an exemplary embodiment, at least a portion of the channels 212 may be provided with, for example, a catalyst to promote a desired reaction. The catalyst may be filled into either or both sets of channels in the form of, for example, foam, felt, lattice or particles. The catalyst may also be coated onto channel walls, including a portion of member 216 that forms the floor of one set of channels and the ceiling of another set of channels.

According to an exemplary embodiment, catalyst supported on foam may be provided to a set of channels 212. According to an exemplary embodiment, and with reference to one set 212 of individual fluid channels, an individual fluid channel of reactor 200 may be thermally connected with up to two (if not up to 14) individual channels of another set 214, as shown by the multiple contacts at 206.

The method may provide for transporting reactants and extracting products from the second set of fluidic channels via the first set of fluidic channels and thermally joining at least one fluidic channel of the first set of fluidic channels with at least two fluidic channels of the second set of fluidic channels, for example as shown in fig. 7A. According to an exemplary embodiment, an endothermic reaction may be provided in one of the sets of fluid channels, for example, fluid channel 212 may have a reactant provided thereto and an endothermic reaction occurs, which may require the use of solar energy to facilitate the endothermic reaction, as shown in fig. 8. According to an exemplary embodiment, the reactor of fig. 7A has a portion (under a portion or face) not shown that can be exposed to solar energy to provide energy to promote or drive the endothermic reaction. According to other embodiments, as the reaction proceeds through the reactor and heated products return through the set of fluid channels 214, the heat of these products is transferred via the member 216 to the endothermic reaction within the channels 212.

Although embodiments of the present disclosure may utilize most metals as materials of construction, metals including nickel, copper, stainless steel alloys, titanium alloys, superalloys such as inconel, hastelloy, and haynes alloys, and combinations thereof, may be utilized. Ceramics are also useful.

The dividing members 216 between the sets of channels may have a flat, concave or convex profile. The partition member may be any thickness required to support the channel structure and provide a thermal conduction path. According to an exemplary embodiment, the partition member may have a thickness of between 0.1mm and 3.2 mm. The partition member may be an impermeable solid.

The height of the individual channels within each group may be less than 100 microns (0.1 mm) or greater than 1 cm. However, in embodiments where a solid catalyst is used, the channel height is preferably greater than 1mm, and more preferably greater than 5mm, in order to provide sufficient catalyst material to support the reaction.

Referring next to fig. 8, a schematic diagram for providing reactants and receiving products from the reactor of the present disclosure is depicted. Accordingly, a method for distributing energy over a reactor, such as the reactor herein, is provided.

In a particular embodiment and referring to fig. 7A, a feed gas mixture of methane and steam enters the reactor 200 at an inlet 202 at the hub and is distributed into a set of identical channels 212 having non-linear sidewalls. The channels traverse approximately one reactor radius and may change their direction by 90 degrees or more from beginning to end. A catalyst is present in each of these channels. The catalyst media may take the form of a foam conforming to the shape of the channels, but may also include a matrix such as particles held in the channels. Each reaction channel may diverge at a short distance from the center so that the catalyst media insert is sufficiently wide near the hub.

Near the edge of the reactor where the channels terminate, slot-shaped openings connect the channels to a second set of channels that are curved in the opposite direction to the first set of channels. The second set of channels 214 may be referred to as heat recovery channels, while the first set of channels may be referred to as reaction channels. The reaction and heat recovery channels are separated by a solid intermediate member 216 that allows heat transfer by conduction. Slot-shaped opening 230 penetrates the intermediate member to allow the flow of reaction product from the reaction channel to enter the heat recovery channel. The product stream returns to the center through the heat recovery channel and exits the reactor through the annular space 204 between the inlet and outlet connecting tubes. Similar to the reaction channel, the heat recovery channel may also be bifurcated.

The helical counter-cross flow mode of the reactor is clearly shown in fig. 5D and 7A, where the three-dimensional model of the reactor is presented in a wire-frame fashion. The reactor structure may alternatively be described by repeating the sequence of the individual flow paths in a circular pattern (circular pattern), as shown in the isometric views of fig. 4-5D:

1. starting from one spiral heat recovery channel, i.e. half of the flow path.

2. One reaction channel of the opposite spiral direction was added.

3. The reaction channel and the heat recovery channel are connected by a slot opening between the reaction channel and the heat recovery channel located near the periphery of the reactor. The reaction channel is shown without catalyst and a portion of the top wall of the reaction channel is removed for clarity.

4. The heat recovery channel is repeated in a circular pattern.

5. The reaction recovery channel is repeated in a circulation pattern (circulation pattern).

6. A complete circular pattern is completed, resulting in a set of spiral reaction channels arranged in a counter-current manner and a set of heat recovery channels of opposite spiral.

The reaction flow under steam methane reforming conditions and non-uniform solar radiation flux distribution of embodiments of the present reactor assembly and method can be simulated to understand the effect of reactor geometry and channel configuration on temperature and thermomechanical stress distribution.

In one embodiment, the reactor provides thermal diffusion over a large reactor area and multiple channels. The non-linear rotation may be one quarter or more of a full circle. In one embodiment incorporating counter-cross flow, the two sets of channels may cover a substantial area of the reactor, thus using a fluid to provide substantial heat diffusion from the hot zone to the cooler zone.

Each feed stream flowing in channel 212 is in thermal contact with the multiple product streams in counterflow channel 214 through partition member 216, the flow path of the latter set of streams covering approximately one fifth of the entire area between the two sets of flow channels. Referring to fig. 7B, the red region is occupied by the feed stream in one channel. The yellow region is the portion of the flow path of all product streams flowing through the feed stream. Thus, the yellow region represents the degree of thermal diffusion provided to each single channel. This region is 18% of the entire region between the hub and the rim.

The counter-flow arrangement of the reaction channels and the recovery channels may provide an efficient heat diffusion for non-uniform solar irradiation to a greater extent than direct heat conduction through the metal layer. The reduction in hot spots results in lower operating and capital costs by improving the operability of the reactor under high throughput conditions and extends reactor life by reducing thermal stress, respectively.

The solar radiant flux distribution on the reactor surface can be estimated from the lunar radiant flux distribution obtained in previous experiments by mapping practice in which a parabolic dish (paraolic dish) points to the full moon. The result is in W/m²Shown in fig. 9, where clearly a plurality of hot spots exist. This flux distribution is specified as a boundary condition on the reactor front for the simulation model. Previous designs of reactors with the non-linear channels of the present disclosure and radial counterflow linear channels with other similar reactor and channel dimensions were simulated for comparison. The linear reactor and non-linear reactor models are shown in FIGS. 10A-10C and FIGS. 11A-11C, respectively.

The reactor surface temperature profiles under a typical set of high solar radiant flux conditions (9.6kW total incident solar energy, > 80% methane conversion, 0.032mol/s methane flow, steam to carbon ratio of 3) are shown in fig. 10B and fig. 11B for linear and non-linear reactors, respectively. The maximum surface temperature was found to be 988 ℃ in the case of the non-linear spiral reverse-flow reactor and to decrease by more than 100 ℃ from the maximum surface temperature of 1114 ℃ in the case of the linear reactor. Visually, the thermal zone on the surface of the non-linear reactor is more evenly spread than the thermal zone on the linear reactor. The excellent heat diffusion of the non-linear reactor is due to any reaction channel below the hot spot being intersected by multiple recovery channels downstream of the hot spot, where a greater amount of the received heat is then diffused to other channels rather than back to the same channel. Conceptually, heat diffusion in a linear reactor can be limited to the area of one wedge-shaped reaction channel, or about 5% of the total surface area. The heat diffusion in the non-linear reactor is at least over the area enclosed by the reaction channels and their connected heat recovery channels, or up to about 18% of the total surface area.

The von mises stress in psi for the linear and non-linear reactors are given in fig. 10C and 11C, respectively. The non-linear reactor has a lower maximum stress than the linear reactor. This difference can be attributed to thermal diffusion and the resulting lower thermomechanical stress.

One embodiment of the present disclosure was tested in a solar thermo-chemical reaction system consisting of a parabolic dish-type solar concentrator, a concentrating (on-sun) reactor unit located at the focus of the dish, and a balance of plant located on the ground. The configuration of the reaction system is given in fig. 8. The photobioreactor unit includes a steam methane reforming reactor, a recuperative heat exchanger, a water evaporator, and an onboard process controller. The feed gas system, water pump, process analysis equipment and tail gas flare apparatus are on the ground. The feed gas was controlled using a mass flow controller. The methane stream is preheated using the product stream through the network of recuperative heat exchangers. The concentrated solar energy is absorbed by the reforming reactor to catalytically convert methane to syngas. The synthesis gas product stream is cooled by the feed gas stream and additional air cooling. The composition of the product gas was analyzed by process gas chromatography. After separation of the condensed water, a product stream is discharged through the flare apparatus.

The non-linear reactor designated TRL 6 was manufactured according to the design described in the previous section. In this particular embodiment of the present disclosure, the reactor is manufactured by processing individual plates and diffusion pressing a stack of plates. The area of the passing reflector and the nominal reflector is 14.85m under the condition of medium-high solar radiation flux²The reactors were tested in pairs with Infinia PowerDish III parabolic dish concentrators. Linear reactors named TRL 5 with other similar reactors and channel dimensions were also manufactured and tested in focus with the same specification of a dish concentrator.

Referring to fig. 12 and 13, reactor performance was evaluated by energy conversion efficiency both at the reaction system level (i.e., the reactor and its heat exchanger mesh plus the dish concentrator) and at the reactor component level (i.e., just the reactor itself). The system solar conversion chemical energy efficiency is defined as the ratio of the higher heating value difference between the reactor product stream and the feed stream to the direct normal solar incidence (DNI) incident on the dish concentrator reflector and thus includes effects due to specular reflectivity, receiver interception, heat loss around the reactor-receiver, and approaching equilibrium chemical conversion in the reactor. The system solar to chemical energy efficiency data from the concentration test is given in fig. 12.

System solar energy conversion chemical energy efficiencies of up to 60% to 70% are achieved with TRL 6 reactor systems. The reactor system is capable of consistently achieving high efficiencies at moderate to very high throughput conditions. The excellent heat diffusion capability of the non-linear reactor design allows the reaction channels to be at higher temperatures when the reactors are operated at the same surface temperature limit. It is believed that the higher thermodynamic efficiency of the endothermic reaction at higher temperatures can offset any additional radiant heat loss, and therefore the overall high solar to chemical energy conversion efficiency of the TRL 6 reactor can be extended to high flux regions.

By comparison, the TRL 5 reactor system does not operate at the same high solar radiation flux as the non-linear reactor system due to the surface temperature exceeding the design point due to the absence of enhanced heat diffusion. Non-linear reactor systems also outperform linear reactors in terms of solar energy conversion chemical energy efficiency in the low to medium solar radiation flux range.

The performance advantage of the non-linear reactor is even more evident when examining the energy efficiency of the reactor. Reactor thermo-chemical efficiency is defined as the ratio of the higher heat value difference between the reactor product stream and the feed stream to the amount of concentrated solar heat energy received by the reactor and therefore includes effects due to heat losses around the reactor-receiver and the extent of chemical conversion in the reactor. Reactor thermal-chemical efficiency data from the light concentration test are given in fig. 13.

TRL 5 reactors achieve 60% to 70% thermo-chemical energy efficiency, but are limited to low to medium flux operation due to hot spot issues and reactor material temperature limitations. With the TRL 6 reactor, up to 85% thermal-chemical energy conversion efficiency is achieved in the high-throughput zone. Some data points indicate that performance is possible even near the 90% level. The superior performance of nonlinear reactors in terms of energy efficiency is attributed to their greater heat diffusion capability.

The flare analysis was performed based on the light gathering performance data of the TRL 6 reactor. The objective is to evaluate the second law efficiency of the reactor and heat exchanger and identify the source and magnitude of the fire damage. In the fire analysis, the fire damage at the front surface of the reactor was estimated by approximating the surface temperature with an average based on IR thermographic measurements. The reference environment was chosen to be 25 ℃ and 1atm, and the chemical composition was proposed by Szargut et al. The flare efficiency of the TRL 6 reactor was determined to be greater than 90%. For example, when tested under conditions of a methane feed flow rate of 0.048mol/s, a steam to carbon ratio of 2.2, a concentrated solar power input of 10.88kW, and an average reactor skin temperature of 820 ℃, the reactor firebreak was estimated to be 5.34kW, resulting in a reactor fireefficiency of 90.2%.