阅读说明：本技术 一种基于毛细纤维编织供水的光热界面蒸发结构和方法 (Photo-thermal interface evaporation structure and method based on capillary fiber woven water supply ) 是由 骆周扬 申震 刘春红 祁志福 鲍华 石劲成 孙士恩 俞华栋 陈永辉 于 2020-04-30 设计创作，主要内容包括：本发明涉及基于毛细纤维编织供水的光热界面蒸发结构,包括水源、隔热材料、毛细纤维网络、光热转化材料和光源；隔热材料固定或漂浮于水源上方,毛细纤维穿过隔热材料编织形成毛细纤维网络,毛细纤维网络下端接触水源,毛细纤维网络上端与光热转化材料接触,光热转化材料上方为光源；水源中的液体通过毛细纤维网络进入光热转化材料的蒸发界面,在光源照射下蒸发。本发明的有益效果是：本发明将毛细纤维通过编织的方式,嵌入隔热材料中,在隔热材料上下形成三维毛细导水网络,为光热转化材料供水,同时实现良好的汲水和隔热效果,实现高效的光-热界面蒸发,获得更高的太阳能利用效率。(The invention relates to a photothermal interface evaporation structure based on capillary fiber woven water supply, which comprises a water source, a heat insulation material, a capillary fiber network, a photothermal conversion material and a light source; the heat insulation material is fixed or floats above the water source, the capillary fibers penetrate through the heat insulation material to be woven to form a capillary fiber network, the lower end of the capillary fiber network is contacted with the water source, the upper end of the capillary fiber network is contacted with the photothermal conversion material, and the light source is arranged above the photothermal conversion material; liquid in the water source enters the evaporation interface of the photothermal conversion material through the capillary fiber network and is evaporated under the irradiation of the light source. The invention has the beneficial effects that: according to the invention, the capillary fibers are embedded into the heat insulation material in a weaving mode, a three-dimensional capillary water guide network is formed above and below the heat insulation material to supply water for the photothermal conversion material, good water absorption and heat insulation effects are realized, high-efficiency light-heat interface evaporation is realized, and higher solar energy utilization efficiency is obtained.)

1. The utility model provides a light and heat interface evaporation structure based on water supply is woven to capillary fibre which characterized in that: comprises a water source (1), a heat insulation material (2), a capillary fiber network (3), a photo-thermal conversion material (4) and a light source (5); the heat insulation material (2) is fixed or floats above the water source (1), the capillary fibers penetrate through the heat insulation material (2) to be woven to form a capillary fiber network (3), the lower end of the capillary fiber network (3) is in contact with the water source (1), the upper end of the capillary fiber network (3) is in contact with the photothermal conversion material (4), and the light source (5) is arranged above the photothermal conversion material (4).

2. The photothermal interface evaporation structure based on capillary fiber woven water supply according to claim 1, wherein: the water source (1) comprises seawater free of suspended particulate matter, fresh water, non-corrosive industrial waste water or non-corrosive organic reagents.

3. The photothermal interface evaporation structure based on capillary fiber woven water supply according to claim 1, wherein: the heat insulation material (2) comprises polystyrene, polyurethane hydrophobic white foam or aerosol; the thickness of the heat insulation material (2) is 1-6 cm.

4. The photothermal interface evaporation structure based on capillary fiber woven water supply according to claim 1, wherein: the capillary fiber comprises natural fiber bundle, nylon, chemical fiber or blended fiber with wetting and capillary properties; the capillary fibers are woven up and down through the insulating material (2) to form a vertical and horizontal three-dimensional network.

5. The photothermal interface evaporation structure based on capillary fiber woven water supply according to claim 1, wherein: the photothermal conversion material (4) comprises single-layer or multi-layer black dyeing fiber cloth with the light absorption rate of more than or equal to 80%, carbon-based material deposition cloth, plasma deposition cloth or carbon-based material blending gel.

6. The photothermal interface evaporation structure based on capillary fiber woven water supply according to claim 1, wherein: the light source (5) comprises simulated sunlight, sunlight under natural conditions or concentrated sunlight obtained by a light-concentrating device, and the illumination area range of the light source is larger than that of the photothermal interface evaporation area.

7. A method of weaving a capillary fiber network based on a photothermal interface evaporation structure of capillary fiber woven water supply as claimed in claim 1, comprising the steps of:

step 1), carrying out configuration design of a capillary fiber network: the capillary fibers vertically penetrate through the heat insulation material (2), the upper surface of the capillary fibers is attached to the photothermal conversion material (4), the lower surface of the capillary fibers is contacted with a water source (1), and the capillary fibers continuously form a horizontal network structure on the upper surface and the lower surface of the heat insulation material (2) respectively, so that a three-dimensional water supply network is formed overall; the horizontal network structure is distributed into a corresponding polar coordinate equidistant divergence circle or rectangular coordinate equidistant rectangle according to the photo-thermal interface evaporation plane shape; the number and the spacing of the capillary fibers in the capillary fiber network (3) are designed according to the photothermal evaporation water supply-heat loss balance: the quantity of the capillary fibers is increased and the space is reduced when the water supply demand is high; if the heat loss is too high, the number of capillary fibers is reduced, and the distance is increased;

step 2), carrying out capillary fiber weaving: vertically penetrating capillary fibers through the heat insulation material (2) to form a capillary fiber network (3) above and below the heat insulation material, wherein the capillary fiber weaving method is divided into manual weaving and automatic weaving; the manual knitting method comprises the steps of knitting by adopting single lines or double lines according to the configuration design of a capillary fiber network, adopting plain or inverted needles according to the space requirement of the water guide network by a needle method, and adopting lockstitch needles at the edges; the automatic knitting method comprises the steps of performing coil chain knitting by a sewing machine according to the capillary fiber network configuration design, using two fiber threads respectively on the upper part and the lower part of the heat insulation material (2), enabling an upper thread to be buckled with a lower coil by needling the heat insulation material (2), and performing step knitting along a network structure.

8. The evaporation method of the photothermal interface evaporation structure based on capillary fiber woven water supply as claimed in claim 1, wherein: liquid in the water source (1) is drawn into the photothermal conversion material (4) through a water guide network woven by the capillary fibers, and is subjected to photothermal interface evaporation under the irradiation of the light source (5).

Technical Field

The invention relates to the field of seawater desalination and photothermal evaporation, in particular to a photothermal interface evaporation structure and method based on capillary fiber woven water supply.

Background

The solar seawater desalination thermal method technology mainly utilizes solar photo-thermal resources to heat seawater, phase change evaporation is carried out on the seawater, and fresh water is obtained through condensation and collection. The photo-thermal solar seawater desalination technology has the advantages of high efficiency, low cost, simple maintenance and the like, and is the mainstream solar seawater desalination technology at present. In the traditional seawater desalination or solar distiller adopting multilevel evaporation and other thermal methods, a heat absorbing medium comprises seawater and a substrate, so that water in an evaporation part is heated, and finally discharged concentrated water is heated. Although the heated concentrated water can be subjected to heat recovery through a heat exchanger or the water body is preheated by using latent heat of condensation in a large-scale seawater desalination facility, the problem of heat loss of the concentrated water is inevitable; in a small-sized seawater desalination plant, the heat loss ratio brought by directly discharging concentrated water is almost equivalent to the concentrated water-evaporation flow ratio. The interface evaporation method is that light absorbing material is arranged at the interface between sea water and air, the thin liquid layer at the interface is heated to evaporate the light absorbing material, and the sea water is continuously absorbed to the heating interface by the water absorbing core or the floating water absorbing material, so that the photo-thermal evaporation process is continuously carried out. The heating mode effectively applies the heat energy converted from sunlight to the thin liquid layer at the interface, and can greatly reduce the heat loss in the evaporation process, thereby improving the evaporation temperature and efficiency. The relevant documents are: zhang Xuan radium, Bo Yuan and Liu Qiang in electric power science and engineering, 2017,33(12):1-8, published "New technical development State of solar seawater desalination" [ J ]; solar-drive interfacial deployment, published in Nat energy3, 1031-1041 (2018), by Tao, p., Ni, g, Song, c.

The main characteristic and advantage of the light-heat interface evaporation technology is that the heat loss in the evaporation heating process is reduced, and particularly the heat leakage loss to seawater is reduced. The technology therefore requires separating the photo-thermal material from the seawater by an insulating material, drawing water from the seawater to the heating interface with as small an area of water conducting channel as possible. However, this technique also requires a comprehensive balance of the water supply-heat loss relationship: if the area of the water guide channel is too small or the water guide efficiency is not high, although the heat leakage loss of the photo-thermal material can be reduced, the evaporation interface is not supplied with water sufficiently, the photo-thermal evaporation efficiency is reduced, a serious salt accumulation phenomenon is caused, the light receiving area is reduced, and the photo-thermal evaporation efficiency is further reduced. The prior art adopts cotton cloth, gauze and other fiber cloth as a water absorption unit, and has the defects of low water absorption efficiency, high heat loss rate, uncontrollable water absorption channel area adjustment and the like. The relevant documents are: ni, G., Zandavi, SH., et al, Energy environ, Sci, 2018,11,1510-1519, A salt-requiring flowing plastic for low-cost evaluation.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a photothermal interface evaporation structure and a method based on capillary fiber woven water supply.

The photothermal interface evaporation structure based on capillary fiber woven water supply comprises a water source, a heat insulation material, a capillary fiber network, a photothermal conversion material and a light source; the heat insulation material is fixed or floats above a water source, the capillary fibers penetrate through the heat insulation material to be woven to form a capillary fiber network (namely a three-dimensional water guide network), the lower end of the capillary fiber network is contacted with the water source, the upper end of the capillary fiber network is contacted with the photothermal conversion material, and a light source is arranged above the photothermal conversion material; liquid in the water source enters the evaporation interface of the photothermal conversion material through the capillary fiber network and is evaporated under the irradiation of the light source.

Preferably, the method comprises the following steps: the water source comprises seawater free of suspended particulate matter, fresh water, non-corrosive industrial waste water or non-corrosive organic reagents.

Preferably, the method comprises the following steps: the heat insulating material comprises polystyrene with the thermal conductivity coefficient less than or equal to 0.1W/(m.K), polyurethane hydrophobic white foam or aerosol; the thickness of the heat insulation material is 1-6 cm.

Preferably, the method comprises the following steps: the capillary fiber comprises natural fiber bundles such as cotton, hemp, wool and silk with wetting capillary performance, chemical fibers such as nylon and glass fiber or blended fibers; the capillary fibers are woven up and down through the insulation material to form vertical and horizontal three-dimensional networks.

Preferably, the method comprises the following steps: the photothermal conversion material comprises single-layer or multi-layer black dyed fiber cloth with the light absorption rate of more than or equal to 80 percent, carbon-based material deposition cloth such as activated carbon, graphene and carbon nano tubes, plasma deposition cloth such as nano gold and silver, and carbon-based material blending gel.

Preferably, the method comprises the following steps: the light source comprises simulated sunlight, sunlight under natural conditions or concentrated sunlight obtained by a light concentrating device, and the illumination area range of the light source is larger than that of the photothermal interface evaporation area.

The capillary fiber network configuration design and weaving method of the photothermal interface evaporation structure based on capillary fiber weaving water supply comprises the following steps:

step 1), carrying out configuration design of a capillary fiber network: the capillary fibers vertically penetrate through the heat insulation material, the upper surface of the capillary fibers is attached to the photothermal conversion material, the lower surface of the capillary fibers is contacted with a water source, and the capillary fibers continuously form a horizontal network structure on the upper surface and the lower surface of the heat insulation material respectively, so that a three-dimensional water supply network is formed overall; the horizontal network structure is arranged into corresponding forms such as polar coordinate equidistant divergence circles or rectangular coordinate equidistant rectangles and the like according to the photo-thermal interface evaporation plane shape; the quantity and the spacing of the capillary fibers in the capillary fiber network are designed according to the photothermal evaporation water supply-heat loss balance: the quantity of the capillary fibers is increased and the space is reduced when the water supply demand is high; if the heat loss is too high, the number of capillary fibers is reduced, and the distance is increased;

step 2), carrying out capillary fiber weaving: vertically penetrating capillary fibers through a heat insulation material to form a capillary fiber network on the upper part and the lower part of the heat insulation material, wherein the capillary fiber weaving method comprises manual weaving and automatic weaving; the manual knitting method comprises the steps of knitting by adopting single lines or double lines according to the configuration design of a capillary fiber network, adopting plain knitting, reverse knitting and the like according to the space requirement of the water guide network by a needle method, and adopting edge locking and the like on the edge; the automatic knitting method comprises the steps of performing coil chain knitting by a sewing machine according to the capillary fiber network configuration design, using two fiber threads on the upper part and the lower part of the heat insulation material respectively, enabling the upper thread to be buckled with the lower coil by needling the heat insulation material, and performing step knitting along the network structure.

According to the evaporation method of the photothermal interface evaporation structure based on capillary fiber woven water supply, liquid in a water source is absorbed into a photothermal conversion material through a water guide network woven by capillary fibers, and the photothermal interface evaporation is performed under the irradiation of a light source.

The invention has the beneficial effects that: according to the invention, the capillary fibers are embedded into the heat insulation material in a weaving mode, a three-dimensional capillary water guide network is formed above and below the heat insulation material to supply water for the photothermal conversion material, good water absorption and heat insulation effects are realized, high-efficiency light-heat interface evaporation is realized, and higher solar energy utilization efficiency is obtained.

Drawings

FIG. 1 is a schematic view of a photothermal interface evaporation structure based on capillary fiber woven water supply;

FIG. 2 is a schematic view of a capillary fiber weave structure;

fig. 3 is a schematic view of a photothermal interface evaporation process based on capillary fiber woven water supply.

Description of reference numerals: the device comprises a water source 1, a heat insulation material 2, a capillary fiber network 3, a photothermal conversion material 4 and a light source 5.

Detailed Description

The present invention will be further described with reference to the following examples. The following examples are set forth merely to aid in the understanding of the invention. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

According to the invention, the capillary fibers are embedded in the heat-insulating material to serve as water guide channels, and the vertical water guide fibers and the horizontal water guide fibers are woven into the three-dimensional water guide structure by using the weaving method, so that a good water drawing effect can be realized by using the capillary phenomenon, high-efficiency three-dimensional network water supply is realized, higher water guide efficiency and relatively lower heat loss rate are realized in unit area, more accurate and simple water supply-heat loss balance regulation performance is realized, and the method is expected to be applied to the light-heat interface evaporation technology to obtain higher solar energy utilization efficiency.

As shown in fig. 1, the photothermal interface evaporation structure based on capillary fiber woven water supply comprises an insulation foam floating above seawater and having low thermal conductivity, a capillary fiber network 3 is embedded in the insulation foam, the lower end of the capillary fiber network 3 contacts the seawater, the upper end of the capillary fiber network 3 contacts with a photothermal conversion material 4, the seawater passes through the insulation foam through a capillary fiber network vertical channel, diffuses in a capillary fiber network horizontal channel and enters a photothermal conversion material evaporation interface, and is evaporated under sunlight irradiation.

The heat insulation foam is as follows: extruded polystyrene foam boards (XPS) having a density of 30kg/m³The thermal conductivity is 0.03W/mK, and the thickness is 1 to 2 cm.

The capillary fiber network is: as shown in FIG. 2, the capillary fiber network 3 comprises cotton threads having hydrophilic wetting wicking properties woven up and down through the insulation material 2 at 0.2cm intervals to form a vertical and horizontal three-dimensional network.

The photothermal conversion material is: the absorbance in the solar spectral range of the activated carbon-deposited fiber cotton cloth with a diameter of 4.6cm circular was 93%.

The weaving mode of the capillary fibers is as follows: as shown in figure 2, according to the horizontal capillary fiber network configuration design of 0.2cm cross spacing, a single-thread plain stitch method is adopted for carrying out reciprocating knitting, black cotton threads of 0.5mm vertically penetrate through heat insulation foam, and a three-dimensional fiber network structure is formed above and below the heat insulation foam.

The flow of photo-thermal interface evaporation based on capillary fiber woven water supply comprises the following steps: as shown in fig. 3, seawater infiltrates the bottom of the capillary fiber network 3, is vertically drawn to the upper part of the capillary fiber network 3, and is diffused to the whole evaporation interface through the capillary channels in the capillary fiber horizontal network; the photothermal conversion material 4 in the evaporation interface converts the absorbed sunlight into heat, heats the seawater adsorbed in the material, and heats and evaporates it.

Examples of photothermal interface evaporation based on capillary fiber woven water supply are as follows: cutting a circular extruded polystyrene foam board heat-insulating material with the diameter of 4.6cm and the thickness of 2cm by using a die, and weaving a black cotton thread three-dimensional water supply network in a reciprocating manner in the middle of foam according to a cross pattern shown in figure 2 at an interval of 0.2cm by adopting a manual single-thread plain stitch method; the lower part of the cotton three-dimensional water supply network is contacted with seawater with the salt content of 3.5 percent, water is transported to active carbon deposition fiber cotton cloth with the diameter of 4.6cm, and sunlight is absorbed on the surface of the active carbon deposition fiber cotton cloth to heat water so as to realize interface evaporation; the experimental result shows that the concentration is 1kW/m²Under the standard sunlight irradiation condition, the evaporation rate of the activated carbon deposition cellucotton cloth material is 1.3kg/m²*h。