In low-temperature processes, there are interactions between heat exchanger network(HEN) and refrigeration system. The modification on HEN of the chilling train for increasing energy recovery does not always coordinat...In low-temperature processes, there are interactions between heat exchanger network(HEN) and refrigeration system. The modification on HEN of the chilling train for increasing energy recovery does not always coordinate with the minimum shaft work consumption of the corresponding refrigeration system. In this paper, a systematic approach for optimizing low-temperature system is presented through mathematical method and exergy analysis. The possibility of "pockets", which appears as right nose section in the grand composite curve(EGCC) of the process, is first optimized. The EGCC with the pockets cutting down is designed as a separate part. A case study is used to illustrate the application of the approach for a HEN of a chilling train with propylene and ethylene refrigerant system in an ethylene production process.展开更多
In this paper, preparation process of nano TiO2 with sol-gel method at low temperature was optimized by response surface method. The nano TiO2 was analysised by DRS and XRD. Result show that： 20mL tetrabutyl titanate...In this paper, preparation process of nano TiO2 with sol-gel method at low temperature was optimized by response surface method. The nano TiO2 was analysised by DRS and XRD. Result show that： 20mL tetrabutyl titanate, 10mL acetic acid, 6mL ethanol dosage, aging time was 29h, aging temperature was 36℃, Nano TiO2 was prepared under the condition. Particle size of nano particles was 37.3nm, Photodegradation rate was 90.2%. It had good photocatalytic ability.展开更多
基金Supported by the National Basic Research Program of China(2010CB720500)the National Natural Science Foundation(21176178)
文摘In low-temperature processes, there are interactions between heat exchanger network(HEN) and refrigeration system. The modification on HEN of the chilling train for increasing energy recovery does not always coordinate with the minimum shaft work consumption of the corresponding refrigeration system. In this paper, a systematic approach for optimizing low-temperature system is presented through mathematical method and exergy analysis. The possibility of "pockets", which appears as right nose section in the grand composite curve(EGCC) of the process, is first optimized. The EGCC with the pockets cutting down is designed as a separate part. A case study is used to illustrate the application of the approach for a HEN of a chilling train with propylene and ethylene refrigerant system in an ethylene production process.
文摘In this paper, preparation process of nano TiO2 with sol-gel method at low temperature was optimized by response surface method. The nano TiO2 was analysised by DRS and XRD. Result show that： 20mL tetrabutyl titanate, 10mL acetic acid, 6mL ethanol dosage, aging time was 29h, aging temperature was 36℃, Nano TiO2 was prepared under the condition. Particle size of nano particles was 37.3nm, Photodegradation rate was 90.2%. It had good photocatalytic ability.
