31results about How to "High solar absorption rate" patented technology

The invention relates to a method for preparing a solar selective heat absorbing paint by using a spinel type pigment as a light absorbent, which belongs to the field of solar heat utilization. The method comprises the steps of uniformly dispersing a nanoscale spinel type pigment as well as resin, a solvent and auxiliaries by using a ball milling method; and then adding a curing agent to obtain the solar selective heat absorbing paint. It is shown in the experiment that the paint is uniformly coated on a metal substrate by using a spraying method; and the solar selective heat absorbing paint obtained after being cured at room temperature shows higher solar energy absorption rate (0.93-0.95) and lower emissivity (0.18-0.30); and the photothermal conversion efficiency of a solar heat collector can be effectively improved; moreover, the coating has the advantages of good mechanical property, stronger weather resistance and service life of more than 45 years.

A spectrally selective solar absorbing coating includes a multilayer stack including, from the substrate to the air interface: substrate (1), infrared reflective layer (2), barrier layer (3), composite absorbing layer (4) consisting of metal absorbing sublayer (4.1), metal nitride absorbing sublayer (4.2), and metal oxynitride absorbing sublayer (4.3), and antireflective layer (5). Therefore, the solar absorbing coating has good high and low temperature cycle stability and superior spectrum selectivity, with a steep transition zone between solar absorption and infrared reflection zones. It has a relatively high absorptance α>95%, and a low thermal emissivity ε≤4%, PC (performance criterion) =−0.3. The solar absorbing multilayer stack can be obtained by reactively magnetron sputtering the metal target in argon or other inert gas with some amounts of gas containing oxygen or nitrogen or their combination.

The invention belongs to the technical field of material preparation, and concretely relates to a MoSi2-SiO2 compound photothermal coating being stable in high temperature air, and a preparation method thereof. The method comprises the following steps: mixing silica sol with MoSi2 powder to form a black suspension, spin-coating a carrier with the black suspension, drying the applied black suspension to obtain a composite layer, and spin-coating the composite layer with the prepared silica sol to form an anti-reflection coating in order to obtain the composite photothermal coating. The coatingprovided by the invention has the advantages of good high temperature stability, simple preparation process, low cost, and suitableness for large-scale production, and also has a high solar absorptionrate and great practical values. The preparation method of the coating is universal, and can be used to prepare functional coatings with different filling materials.

The invention discloses a preparation method of a wood-based solar energy seawater desalination material. The steps are as follows: cutting wood transversely along the growth direction; then ultrasonically cleaning it with deionized water for 15-25 minutes, and then soaking it in a dilute sulfuric acid solution for 10-30 minutes ; After taking out, soak the wood sample in potassium permanganate solution for 30-60min, and then heat it at 60-80°C for 1-2h; after heating, take out the wood sample and wash until the filtrate is neutral , drying to obtain a wood-based solar water desalination material with black manganese dioxide deposited on the surface. The invention uses wood cut laterally along the growth direction as the raw material, and has the advantages of light weight, good hydrophilicity, low cost, etc.; at the same time, it also has natural water transportation channels, high light-to-heat conversion efficiency, and can fully utilize solar energy to achieve high efficiency. Seawater desalination can be directly applied to large-scale industrial production and market promotion.

The invention discloses a method for preparing a black extinction film layer with high solar energy absorption rate and high emissivity on the surface of a titanium alloy, which relates to a method for preparing a ceramic film layer on the surface of a titanium alloy. The purpose of the invention is to solve the problems of low solar energy absorption rate, low self-emission rate and low binding force between the film layer and the base body existing in the coating on the surface of the titanium alloy. Methods: 1. Titanium alloy pretreatment; 2. Micro-arc oxidation to obtain a black extinction film with high solar energy absorption rate and high emissivity on the titanium alloy surface. The thickness of the black extinction film with high solar energy absorption rate and high emissivity on the surface of the titanium alloy prepared by the invention is 20 μm to 30 μm, the roughness of the film layer is 0.5 μm to 3 μm, the solar absorption rate is 0.95 to 0.98, and the emissivity is 0.93 to 0.97 . The invention discloses a method for preparing a black extinction film layer with high solar energy absorption rate and high emissivity on the surface of a titanium alloy.

The invention discloses a heat-absorbing material of a nickel-containing alloy hollow sphere and a preparation method thereof. The heat-absorbing material is prepared from the following raw materialsin parts by mass: 20 to 30 parts of nickel alloy hollow spheres, 10 to 20 parts of silicon resin, 10 to 60 parts of epoxy resin, 10 to 20 parts of ethyl alcohol, 2 to 4 parts of silane coupling agents, 1 to 3 parts of silica sol, 1 to 10 parts of nanometer aluminum oxide powder and 1 to 10 parts of nanometer ferric oxide powder. The preparation process is simple; the cost is low; the industrial production is easy; the stability is high; a coating prepared from the material has high heat absorption rate and low light emission rate; good mechanical performance and higher weather resistance are realized.

The invention discloses a solar central water heating system with a heat accumulation function, which comprises a solar thermal collector array, a water tank, a collector circulating pump, a check valve, an electromagnetic valve and other parts. A heat accumulator filled with phase-change heat accumulation medium is arranged on the bottom in the water tank, and the interior of a heat accumulator core tube is a water passage. A heat accumulator water passage inlet is connected with the outlet of the solar thermal collector array, a heat accumulator outlet is directly open in the hot water storage tank, and the inlet of the solar thermal collector array is connected with the bottom of the hot water storage tank sequentially through the check valve and the collector circulating pump and connected with a tap water supply pipeline through the water-lifting electromagnetic valve. Both hot water heated by the solar thermal collectors and cold water replenished into the water tank first flow through the heat accumulator core tube and exchange heat with the heat accumulator. When the water temperature in the water tank is higher or lower than the phase change temperature of the heat accumulation medium in the heat accumulator, heat is released to the heat accumulator or heat is absorbed from the heat accumulator. By means of the heat absorption and release of the heat accumulator, energy consumption can be reduced, and solar radiation energy can be effectively utilized by the way of peak load shifting.