Study On The Cold Energy Of Liquefied Natural Gas In Cryogenic Pulverization Of Waste Tyre

In order to effectively eliminate more and more "Black Pollution" formed by waste tyre are gradually threatening the human living environment, which is powdered rubber through grinding at low temperature, which is widely used. At the same time, Liquefied natural gas (LNG) releases a lot of plenty of cold energy during its boil-off. If it do not be utilized, LNG will cause "Cool Pollution".For high energy consumption and large exergy consumption of the actual pulverization, the cryogenic pulverization technology of LNG cold energy utilization can be used.In order to reduce the energy consumption of rubber powder through cryogenic comminution of waste tyre and sufficiently utilize the cold energy of LNG, a process of cold energy utilization of waste type cryogenic comminution is proposed. With air used as a middle cold medium, the cold energy of LNG was transferred to air, and the cold air was used to blow, cool rubber granules. The characteristic of main facilities was analyzed, and the equity calculation of mass and cold energy was accomplished, to get the effective use of cold energy.Based on thermodynamic principle, cold exergy of LNG was analysed. Based on the trait of the cold energy of LNG in cryogenic pulverization process of waste tyre, the paper represented the analysis model of exergy analysis for the six plants with the method of three-box models and given the computing formula of exergy analysis, the functions of exergy loss are obtained. The paper provides the theory reference for improvement and optimization of the system.Air cooler is a significant equipment of exergy loss. The equipment depreciation and the exergy cost of recovery cold energy are taken into account, the maximal net income is taken as object function, and the outlet temperature of the air cooler is taken as variable. Using Matlab software, exergy economic optimization of the air cooler is made. The outlet temperature of the air cooler and maximal net income pre-year are obtained. The temperature parameter of the process provides a reference for practical engineering application.