| With the rapid development of national economy and improvement of people’s living standards, the society electricity consumption increased year by year, but the electrical load is low, the contradiction of the short at peaks and the surplus at valleys of power supply have become increasingly prominent. In this context, cool-storage technology evolved. Cool-storage technology can transfer the peak load to the valley, ease the pressure of electric power at peaks, increase the utilization of refrigeration equipments. It is an energy-saving technology which can promote the development of energy, economy and environment. As a superior cool-storage medium, ice slurry has enormous latent heat and advanced liquidity. Compared to other cool-storage media, it has a significant advantage whether in economy or energy efficiency. Currently, how to prepare ice slurry stably and efficiently has become a hot topic of ice storage technology.This paper studies the dynamic ice-making technology in cool-storage technology. It introduced the research status of ice slurry preparation system and the use of ice slurry technology in various fields, overviewed ice slurry preparation methods briefly, with the theory of growth of ice crystals and principle of super-cooled ice preparation, learned from predecessors research and built an ice slurry preparation experimental system. The main work is embodied as follows:(1) This paper built a continuous ice slurry preparation experimental system independently. The system is made up of the cooling system, the secondary refrigerant system, supercooled water circulating system and data acquisition system. The water of 0℃ from the ice storage tank is filtered and pumped over to the subcooler, cooled to below 0℃ forming supercooled water after exchanged heat with secondary refrigerant; supercooled water generates ice crystals by releasing means and sends ice crystals produced to the ice storage tank. Ethylene glycol solution was used as secondary refrigerant, after exchanged heat with the refrigerant transmitted cold to water, reduced the influence of temperature fluctuations on ice refrigeration process. Experiment used plate heat exchanger as subcooler and add pp-cartridge filter in front of the plate heat exchanger. Data acquisition system can monitor and record inlet and outlet temperature and flow of subcooler over the course of the experiment.(2) The experimental study used the control variable method. The experiment used tap water and purified water, got maximum supercooling degrees of different ice-making solution, combined to the ice crystals generation theory, analyzed the influence of impurity particles to the process of ice-making of the experimental system. The presence of foreign particles promoted to generating the ice from supercooled water. The experiment analyzed the data of different chiller cooling capacity, glycol flow and water flow, got supercooled water temperature and temperature curves under different experimental conditions, obtained the influence of the cooling rate, water flow, glycol flow and other factors on the impact of the degree of supercooling and the process of ice-making. The experiments used strainers, plate and ultrasonic generator as supercooling releasing means,.Experimental results show that the ultrasonic generator is the best to release the supercooling of supercooled water.(3) The experiment studied on the ice block of the system, analyzed the reason of ice block phenomenon. By using ultrasonic generator release supercooling, added filters and other methods to improve the system, the experiment solved the problem of ice block. The ice slurry preparation system can operate stably and generate ice crystals continuously. |
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