Experimental investigation of bubble group and temperature distribution uniformity in the direct contact boiling heat transfer process

A solar thermochemical reformer/receiver which combines a ST-μFB reformer and a catalytic bed of micro-sized particles offers a novel approach for the solar-driven catalytic steam reforming of methanol (SDCSR-MeOH) method. Heat transfer, mass transfer and solar thermochemical conversion performance have a great significance on the SDCSR-MeOH method due to high interfacial absorption surface of micro-sized particles. The solar radiation has been coupled to the ST-μFB reformer as a novel driving energy for conducting the endothermic reactions of methanol (CH3OH) inside ST-μFB reformer to produce solar H2. Solar H2 had won an important role as renewable feedstocks for different chemical processes and particularly in fuel cells applications. A non-isothermal mathematical model was described by a set of partial differential equations (PDEs) that couples to a complex kinetic model of the SDCSR-MeOH employing the Cu/ZnO/Al2O3 catalyst. The system of novel PDEs has been transformed into simpler system of ordinary differential equations using the coupled integral equation approach. Validation results demonstrate that the two validated cases for the reaction temperature against the simulated results by authors had reached a good fit as well as the solar thermochemical conversion of CH3OH. The temperature profiles of the gas phase, solid phase and ST-μFB reformer wall were simulated at three different positions from ST-μFB reformer. The reactant and product distributions inside ST-μFB reformer were analysed at two different reaction temperatures. The effect of the reaction temperature was studied on the conversion of CH3OH and yield of H2. In addition, the action of the weight hourly space velocity has been analysed on the conversion of CH3OH.

Mathematical modelling of the solar-driven steam reforming of methanol for a solar thermochemical micro-fluidized bed reformer: thermal performance and thermochemical conversion

Oxygen concentration variation in ullage influenced by dissolved oxygen evolution

CFD Simulation of a bubble column evaporator

Modeling and optimization of the thermal-hydraulic performance of direct contact heat exchanger using quasi-opposite Jaya algorithm

Simulation on direct contact heat transfer in gas-molten salt bubble column for high temperature solar thermal storage

The invention discloses a compressed supercritical carbon dioxide energy and heat storage system and a working method thereof, and belongs to the field of energy storage. The system comprises a motor, a compressor, a low pressure supercritical carbon dioxide storage tank, a cooler, a heat accumulator, a high temperature oil tank, a high pressure supercritical carbon dioxide storage tank, a low temperature oil pump, a low temperature oil tank, a high temperature oil tank, a preheater, a heat regenerator, a heater, a turbine and a power generator. In a trough period of a load of a power grid, electric energy is used for compressing supercritical carbon dioxide; and in a peak period of the load of the power grid, the compressed supercritical carbon dioxide is released to push the turbine to do work to generate power. The system can simultaneously store energy and heat to realize conventional 'peak-load shifting'; compared with conventional compressed air, the compressed supercritical carbon dioxide can reduce the volume of a storage tank and save compression power; and by the adding of heat conduction for circulation, the heat efficiency of the whole system can be improved.

Compressed supercritical carbon dioxide energy and heat storage system and working method thereof

The invention discloses a direct-contact heat exchange tower type solar thermal generating station system and a working method thereof, and belongs to the field of solar thermal utilization. The system comprises a heliostat field, a heat absorber, a molten salt heat storage and release subsystem, a turbine, an electric generator, a preheater, a cooler and a compressor. Sunlight is reflected into the heat absorber through the heliostat field, after air is compressed, high-temperature and high-pressure air is generated through the heat absorber to push the turbine to apply work for power generation, and the working method is adjusted by combining with the molten salt heat storage and release subsystem according to differences of solar energy intensity. According to the direct-contact heat exchange tower type solar thermal generating station system and the working method thereof, by means of the characteristics that molten salt is low in vapor pressure and wide in using temperature range, an air and molten salt direct-contact heat exchange mode is adopted for replacing traditional wall-type heat exchange, the heat exchanger efficiency can be improved, and a heat exchange temperature difference can be reduced; meanwhile, the air serves as a working medium, the phenomena of large-range flow-induced corrosion and frozen blocking of the molten salt in a pipeline are avoided. Meanwhile, continuous and stable operation under different solar energy intensity conditions can be achieved, and stable high-quality electric energy can be provided.

Direct-contact heat exchange tower type solar thermal generating station system and working method thereof

The invention discloses a temporary refrigeration storage box for semiconductor refrigerating sheets and a working method of a temporary refrigeration storage box and belongs to the field of refrigeration. The device comprises a box body. A small partitioning box body needing refrigeration is arranged in the box body. A box door is arranged on the box body. The device further comprises a fan, cold guiding sheets, a refrigerating sheet array, radiating sheets, a temperature sensor, an infrared sensor and a solar distributed power supply. The temporary refrigeration storage box can be used for storing vegetables, melons, fruits and the like in batches in a classified mode and applied to various occasions. At present, various temporary boxes capable of storing objects are arranged at doorways of supermarkets, but no refrigeration storage box which can be used for storing raw foods is arranged, and the temporary refrigeration storage box is used for storing the raw foods. According to the temporary refrigeration storage box for the semiconductor refrigerating sheets, the defects of large noise, large size, complex structure and high cost which are caused by using a compressor in a traditional refrigeration box are changed.

Temporary refrigeration storage box for semiconductor refrigerating sheets and working method of temporary refrigeration storage box

The invention discloses a dedusting device using a multi-stage direct current cyclone separator combined array and a method thereof, and belongs to the dedusting field. The device includes a multi-stage direct current cyclone separator array, a gas intake port, a gas discharging port, a dust discharging port, a dust discharging fan and the like. The device is characterized in that the direct current cyclone separator array is used for treating dust-containing gas flow; the dust-containing gas flow enters the device from the gas intake port, is treated by the multi-stage direct current cycloneseparator array and then is divided into two strands of gas with a large flow quantity and a small flow quantity respectively; clean gas flow having relatively large flow quantity is discharged from the gas discharging port; the dust-containing gas flow having relatively small flow quantity and carrying a large amount of dust is discharged from the dust discharging port under the action of the dust discharging fan, and the dust-containing gas flow is separated. Compared with a conventional gas separation and purification device, the device has the advantages that the pressure dropping caused by separation is greatly reduced, and the device can work continuously with mass flow for a long time without replacement of any parts under a condition of maintaining relatively high separation efficiency.

Yang Ning

Papers

Simulation on direct contact heat transfer in gas-molten salt bubble column for high temperature solar thermal storage

Compressed supercritical carbon dioxide energy and heat storage system and working method thereof

Direct-contact heat exchange tower type solar thermal generating station system and working method thereof

Temporary refrigeration storage box for semiconductor refrigerating sheets and working method of temporary refrigeration storage box

Dedusting device using multi-stage direct current cyclone separator combined array and method thereof