CN103372413B - A kind of metallic foam support catalytic bed solar absorption reaction unit - Google Patents
A kind of metallic foam support catalytic bed solar absorption reaction unit Download PDFInfo
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- CN103372413B CN103372413B CN201210105341.6A CN201210105341A CN103372413B CN 103372413 B CN103372413 B CN 103372413B CN 201210105341 A CN201210105341 A CN 201210105341A CN 103372413 B CN103372413 B CN 103372413B
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Abstract
The invention discloses a kind of metallic foam support catalytic bed solar absorption reaction unit, this device comprises linear solar absorption reactor and parabolic trough type solar concentrator, and linear solar absorption reactor is placed in the focal line place of parabolic trough type solar concentrator; Linear solar absorption reactor is sleeve structure, comprise outside glass bushing, inner metal tube, metal tube surface evaporation selective coating and be placed in metal tube using metal foaming material as the beds of carrier.The present invention makes full use of space in reactor, and catalyst bed Rotating fields can holding structure be even, stable for a long time, longer service life, and it is high that solar energy is converted into heat energy efficiency; Beds has higher specific area, and its catalytic performance is better; Replacing and the regenerative operation of catalyst are more convenient, solve that current reactor catalyst specific area is low, internal accelerator fills uneven, temperature field and flow field is difficult to difficult problems such as controlling, difficult in maintenance.
Description
Technical field
The present invention relates to solar energy heating and hot technical field of power generation, particularly relate to a kind of parabolic trough type metallic foam support catalytic bed solar absorption reaction unit, use metal foaming material to make the carrier of beds.
Background technology
The energy is the basis of human survival and development, along with the progress of human society, on the one hand, owing to advancing in living standard and promoting the needs of social development, the mankind increase day by day for the demand of the energy, traditional fossil energy total amount is limited, non-renewable on the other hand, and the use procedure of fossil energy simultaneously produces and greenhouse gas emission along with serious pollutant.Day by day exhausted fossil energy and the ever-increasing energy demand of the mankind, and sharp-pointed contradiction is defined to an urgent demand of environmental protection, have a strong impact on the sustainable development of the mankind.The regenerative resource that development and utilization solar energy etc. clean alleviates energy supply and demand contradiction, and conservation of nature environment, realizes the important channel of sustainable development.
The utilization of solar energy mainly contains solar photoelectric and transforms and solar energy thermal transition.Solar heat chemical technology is a kind of form of solar energy optical-thermal trans-utilization, utilizes thermochemical reaction process, assembled solar energy is converted into the chemical energy of fuel, or utilizes solar energy, for heat absorption chemical process provides heat.Salar light-gathering technology comprises the types such as parabolic trough type, tower, dish-style, wherein parabolic trough type Salar light-gathering technology relative maturity, adopts the solar heat chemical technology of parabolic trough type heat collector to have commercial off-the-shelf prospect.
Solar heat chemical reactor mainly contains three kinds of forms: (1) indirect heating type, and thermal-arrest working medium absorbs solar energy in heat collector, then enters reactor heat exchange and solar thermal energy is supplied to chemical reaction; (2) direct-heating type, chemical reactor is directly heated in solar collector; (3) direct radiator type, direct irradiation of sunlight is on beds.Indirect heating type reactor, reactor is heated evenly, and is convenient to control, but heat transmission equipment is many, and heat loss is larger; Direct-heating type reactor, start-up time is short, but it is uneven to be heated, and easily causes hot-spot and catalyst failure; Direct radiator type reactor, there are certain requirements the optical characteristics of reactor material and catalyst.
Traditional fixed-bed catalytic filler mode inside adopts simple stacking filler mode, as reaction bed in the packed catalyst process fluid of cylinder particle composition.There is following problem in this catalyst filling mode:
First, conventional filler mode easily causes the inner skewness of bed, and catalyst can not fill up pipe in whole absorption reactor thermally, due to Action of Gravity Field, pipe inner top may be filled by catalyst-free, causes the waste in absorption reactor thermally space, and affects decomposition reaction efficiency.Simultaneously because absorption reactor thermally needs the position of following the tracks of the sun to run, it is moving component, inner catalyst filling particle can move along with the motion of absorption reactor thermally, cause the uneven of inner stuffing further on the one hand, Long-Time Service rear catalyst particle may concentrate on bottom absorption reactor thermally, bottom catalyst bed layer porosity is caused to decline, and reactor head catalyst-free; The friction of another aspect catalyst granules and shock can reduce the service life of absorption reactor thermally.
Secondly, the arrangement of bed internal accelerator particle is wayward, be difficult to the flow and temperature fields of effective tissue reaction's bed inside, intraductal heat exchange poor performance, may occur that local reaction thing can not be discharged in time thus affect chemical reaction rate, and the too high catalyst failure of local temperature or temperature are lower than the situation of the temperature of applicable reaction.
Again, the specific surface area of catalyst of conventional filler mode is on the low side, and specific area is the important parameter of catalyst performance, and the specific area of catalyst is low, and catalyst performance is difficult to improve, and chemical reaction rate is low, affects whole system performance.
Finally, through using catalyst to lose efficacy for a long time, and the catalyst changing this simple filling batch needs the catalyst in reactor to topple over out fresh catalyst to be poured into reactor again, and plant maintenance process is complicated.
The present invention breaches the reactor of conventional filler mode, introduces metal foaming material, as the carrier of catalyst, is attached on the surface of metal foaming material, forms new catalyst bed configurations by techniques such as infusion process or powder coated methods by catalyst.Use the absorption reactor thermally of this new construction catalyst bed to be all better than conventional filler mode in catalyst performance, heat-transfer capability and flow resistance etc., the cost of maintenance is also than reduction.
Summary of the invention
(1) technical problem that will solve
There is shortcomings in the solar heat chemical reactor of conventional filler mode, such as internal accelerator filler is uneven, temperature field, flow field are difficult to tissue, fluid resistance loss is large, specific area is low, and the problem such as difficult in maintenance, and main purpose of the present invention is to provide a kind of metallic foam support catalytic bed solar absorption reaction unit, to improve flowing in absorption reactor thermally, heat exchange and catalytic performance, improve the performance of solar heat chemical catalysis reaction system.
(2) technical scheme
For achieving the above object, the invention provides a kind of metallic foam support catalytic bed solar absorption reaction unit, this device comprises linear solar absorption reactor 5 and parabolic trough type solar concentrator 6, and linear solar absorption reactor 5 is placed in the focal line place of parabolic trough type solar concentrator 6; Linear solar absorption reactor 5 is sleeve structure, comprise outside glass bushing 4, inner metal tube 2, at the selective coating 3 of the surperficial evaporation of metal tube 2 and the beds 1 that is placed in using metal foaming material as carrier in metal tube 2.
In such scheme, be evacuated to suppress heat convection between described metal tube 2 and described glass bushing 4.
In such scheme, described parabolic trough type solar concentrator 6 tracking position of sun, the sunshine of reflection converges on the selective coating 3 on metal tube 2 surface being positioned at concentrator focal line through glass bushing 4.
In such scheme, described beds 1 is processed into cylindrical shape by metal foaming material.
In such scheme, the described beds 1 using metal foaming material as carrier is uniformly covered with chemical reaction catalyst.
In such scheme, in described glass bushing 4 and metal tube 2 sealing-in place, use bellows, to mate the thermal expansion of metal tube 2 and glass bushing 4.
(3) beneficial effect
As can be seen from said apparatus and technical scheme, the present invention has following beneficial effect:
1, metal foaming material can be processed into the shape of applicable metal tube, for the absorption reactor thermally of different tube diameters, different pipe range, thus can make it to fill up space in metal tube, makes full use of space in metal tube and carries out chemical reaction.Metal foaming material integrally, is easily fixed in absorption reactor thermally metal tube after processing, through Long-Time Service also can holding structure evenly, stable, and and without relative motion between metal tube, prolongation metal tube service life.
2, metal foaming material can be as required, the structural parameters such as porosity, hole density, specific area needed for being obtained by certain foam process, be convenient to the performance needing to adjust beds according to difference, the flow resistance of equilibration catalyst bed and heat exchange, catalytic performance, to organize and to optimize working medium in the flow field of catalyst bed interlayer, temperature field, promote the carrying out of chemical reaction.Metal foaming material itself has excellent heat conductivility, conducts rapidly the solar energy of absorption to working medium, provides reaction institute calorific requirement, and makes the region, temperature field in metal tube even.
3, the beds unit pipe range surface area that metal foaming material makes carrier can reach more than 3 times of simple filler mode, and when catalyst type is constant, its catalytic performance is better than the beds of original simple material filling type.The catalytic reaction of heat absorption is the core place of solar heat chemical reaction, improve the performance that catalyst performance can promote solar heat chemical reaction system, improve the transformation efficiency of solar energy to chemical energy, the mirror scene that reducing system needs is amassed, thus effectively reduces investment and cost.
4, the beds of Long-Time Service there will be the situation of catalyst activity reduction, and new catalyst bed can take out from metal tube as a whole easily, replace with the catalyst bed of brand-new, or carry out catalyst regeneration, to keep the activity of catalyst bed, safeguard that more original absorption reactor thermally is more convenient, recycle metal foaming material cost and also reduce.
5, this device adopts absorption reactor thermally integrated design, decreases indirect heat exchange loss, simplified apparatus.
Accompanying drawing explanation
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is further described.
Fig. 1 is the schematic diagram of the metallic foam support catalytic bed solar absorption reaction unit according to the embodiment of the present invention.Device comprises parabolic trough type solar concentrator 6, linear solar absorption reactor 5, and linear solar absorption reactor 5 is arranged on parabolic trough type solar concentrator 6 focal line place.
Fig. 2 is the schematic diagram of Fig. 1 neutral line solar absorption reactor 5.Wherein 1 is cylinder metal foaming structure catalyst bed, take metal foaming material as carrier, its surface coverage catalyst; 2 is metal tube, and material is usually by stainless steel etc.; 3 selective coatings plated outward for metal tube surface, this coating has very high absorptivity and low emissivity for solar spectrum; 4 is outside glass bushing, and glass bushing is made up of heat resistant glass, at high temperature has excellent intensity and light transmission rate.Vacuumize between metal tube and glass tube.
Fig. 3 is the structure 1 metallic foam support catalytic bed that Fig. 1 neutral line solar absorption reactor 5 comprises, and it is dimensioned slightly smaller than the inside dimension of metal tube, can entirety insert in metal tube.
Fig. 4 is the cross-sectional view of Fig. 1 neutral line solar absorption reactor 5, and in figure, mark is identical with Fig. 2.
Detailed description of the invention
For making the object, technical solutions and advantages of the present invention clearly understand, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.
As shown in Figure 1, the invention provides a kind of metallic foam support catalytic bed solar absorption reaction unit, this device comprises linear solar absorption reactor 5 and parabolic trough type solar concentrator 6, and linear solar absorption reactor 5 is placed in the focal line place of parabolic trough type solar concentrator 6; Linear solar absorption reactor 5 is sleeve structure, comprise outside glass bushing 4, inner metal tube 2, the surperficial evaporation of metal tube 2 selective coating 3, be placed in beds 1 using metal foaming material as carrier metal tube 2 in, and remove compression ring, bellows.Wherein the absorptivity of selective coating 3 pairs of solar spectrums can reach more than 0.9, and emissivity is low to moderate less than 0.2, to reduce the external radiation heat loss of Metal absorption pipe.
Metal tube 2 inside uses metal foaming material, as the carrier of catalyst.Metal foaming material is processed into cylindrical shape, and cylindrical cross section diameter is slightly less than the internal diameter of metal tube 2, and cylinder height is slightly less than the length of metal tube 2; By techniques such as infusion process or powder coated methods, make catalyst adhere on the surface of cylinder metal foamed material after processing equably, form catalyst bed 1, as shown in Figure 3.The metallic foam catalyst bed 1 made is inserted in metal tube 2.In Fig. 2, glass bushing 4 is made up of heat resistant glass, at high temperature has excellent intensity and light transmission rate.Be evacuated to suppress heat convection between glass bushing and Metal absorption pipe.In glass bushing and metal tube sealing-in place, use bellows, the thermal expansion of Metal absorption pipe and glass bushing can be mated like this.
In actual use, solar absorption reactor is connected, is arranged on parabolic trough type heat collector focal line place, absorb the solar energy converged, and metal inner pipe is connected, reach the total length required for system.At absorber metal inner pipe.Pass into gaseous reactant in metal tube one end, gas is along the catalyst bed intrastratal flow of metal pipe range at metal foaming material carrier.The solar heat absorbed makes the temperature of metal tube internal catalyst bed rise to the temperature of suitable reaction, and provides reaction heat for decomposition reaction.The beds of metallic foam support provides good heat exchange, flowing and catalytic perfomance, the solar heat absorbed easily forms the temperature of uniform suitable reaction in metal tube, the beds of metal foaming material carrier provides very large specific area simultaneously, be conducive to the carrying out of cartalytic decomposition effect, issue biochemical reaction in preference temperature and catalyst action.
For solar energy Thermochemical Decomposition methyl alcohol, methyl alcohol is called as " the omnipotent intermediate " of chemical industry, from the multiple fossil energy synthesis such as coal, natural gas, can originate very extensive.Utilize solar energy to provide the reaction heat of methanol oxidation cracking, producing hydrogen and carbon monoxide synthetic gas, is a kind of mode of middle low-temperature solar chemical utilization.Normal temperature methyl alcohol is liquid, convenient transportation, the synthesis gas that Methanol Decomposition produces both can use as fuel, also can obtain hydrogen, carbon monoxide by being separated, as the raw material of industry, the method for therefore this Driven by Solar Energy thermal chemical reaction hydrogen manufacturing has vast potential for future development.Application the present invention realizes solar heat chemical breakdown methyl alcohol system, beds 1 in metal tube is along pipe range direction flowing methyl alcohol, 5 is parabolic trough type concentrator, concentrator reflected sunlight converges in through glass bushing in the coating 3 of the metal tube absorber surface being positioned at concentrator focal line, coating 3 working medium absorbed in solar energy heating pipe reaches the temperature of suitable methanol decomposition reaction, and methyl alcohol is decomposed into hydrogen and the Co mixed gas that mol ratio is 2: 1 under the effect of metallic foam support catalytic bed.
Compare the reactor of conventional filler mode, the present invention makes full use of space in metal tube, and catalyst bed Rotating fields can holding structure be even, stable for a long time, metal tube absorber longer service life; The heat energy that solar energy transforms conduction efficiency in pipe is higher, the region, temperature field in pipe evenly, working medium has flow field preferably, temperature field at catalyst bed interlayer, the carrying out of promotion chemical reaction; Beds has higher specific area, and its catalytic performance is better than the beds of original simple material filling type; After a period of time is run, the maintenance of new construction is more convenient.
Above-described specific embodiment; object of the present invention, technical scheme and beneficial effect are further described; be understood that; the foregoing is only specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (3)
1. a metallic foam support catalytic bed solar absorption reaction unit, it is characterized in that, this device comprises linear solar absorption reactor (5) and parabolic trough type solar concentrator (6), and linear solar absorption reactor (5) is placed in the focal line place of parabolic trough type solar concentrator (6); Linear solar absorption reactor (5) is sleeve structure, comprise outside glass bushing (4), inner metal tube (2), at the selective coating (3) of metal tube (2) surperficial evaporation and the beds (1) that is placed in using metal foaming material as carrier in metal tube (2);
Wherein, described beds (1) is processed into cylindrical shape by metal foaming material, be filled in metal tube (2) completely, the described beds (1) using metal foaming material as carrier is uniformly covered with chemical reaction catalyst;
Described parabolic trough type solar concentrator (6) tracking position of sun, the sunshine of reflection converges on the selective coating (3) on metal tube (2) surface being positioned at concentrator focal line through glass bushing (4).
2. metallic foam support catalytic bed solar absorption reaction unit according to claim 1, is characterized in that, be evacuated to suppress heat convection between described metal tube (2) and described glass bushing (4).
3. metallic foam support catalytic bed solar absorption reaction unit according to claim 1, it is characterized in that, in described glass bushing (4) and metal tube (2) sealing-in place, use bellows, to mate the thermal expansion of metal tube (2) and glass bushing (4).
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| CN201210105341.6A CN103372413B (en) | 2012-04-11 | 2012-04-11 | A kind of metallic foam support catalytic bed solar absorption reaction unit |
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| CN201210105341.6A CN103372413B (en) | 2012-04-11 | 2012-04-11 | A kind of metallic foam support catalytic bed solar absorption reaction unit |
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| CN109695966B (en) * | 2019-01-18 | 2020-11-10 | 河北赛特驰实验器材销售有限公司 | New application of selective light absorption material and novel photo-thermal system |
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| CN110467154A (en) * | 2019-09-30 | 2019-11-19 | 云南师范大学 | A kind of solar energy methanol steam reforming hydrogen manufacturing focusing reactor |
| CN111185125B (en) * | 2020-01-08 | 2022-04-22 | 中国科学院工程热物理研究所 | Catalyst activation apparatus and method |
| CN112791670B (en) * | 2020-12-23 | 2022-08-19 | 南京大学 | Interfacial thermocatalytic system |
| CN114534665B (en) * | 2022-02-23 | 2023-05-23 | 苏州大学张家港工业技术研究院 | Expandable flow tube type photocatalytic reaction device and method |
| CN114719451B (en) * | 2022-03-10 | 2023-02-21 | 华中科技大学 | Photo-thermal-electric-thermal complementary thermochemical energy storage device |
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