Study On Energy Consumption Estimation Method In The Process Of TiO₂Nano Thin Film Preparation By LPCVD

With continuous research and development for Nano-TiO2film, it’s unique and perfect performance has been gradually shown in work and livelihood, and Nano-TiO2film is still applied in many fields. However, there are many questions existing in preparation of nano-TiO2film by LPCVD, such as high energy consumption, low material utilization. Which is against with the shortage of natural resources and the idea of saving energy and improving energy efficiency that people increasingly advocated. It is not good at sustainable production of nano-TiO2film.Case study is conducted on a Low Pressure Chemical Vapor Deposition (LPCVD) process for nano-TiO2film preparation in this paper. Firstly, the speed of transportation of gaseous mixture is obtained as a function of stress gradient and viscosity by combining film preparation techniques and fluid dynamics with boundary conditions and liquid status in the preparation of nano-TiO2film. At the same time, the function on concentration of precursor Ti(OC3H7)4can be obtained by using Fick’s first law and gaseous transport properties, and finally deposition rate of nano-TiO2film can be calculated. The distance between the substrate and upper boundaries of reactor and the parameter x are considered as a significant parameters in this function, which determine the deposition rate of nano-TiO2film on different range of the substrate.Secondly, the parametric thermodynamic model on chemical reaction and precursors can be established by using chemical engineering thermodynamics and thermodynamic laws. Then, the value of thermodynamics on precursors and chemical reaction under the specified conditions in the preparation of nano-TiO2film can be obtained.Thirdly, after identifying various parts energy consumption in the preparation of nano-TiO2film, according to energy balance and material balance, the value of various parts’ energy consumption in different temperature range of the reactor can be getted by using relative thermodynamics theories and the mass flow of precursor, the ratio of energy loss used for chemical reaction to totally energy consumption can be calculated by analyzing various parts’energy consumption.Finally, the grid model of reactor for the preparation of nano-TiO2film can be established, the images of temperature distribution field in the reactor, the gaseous mixture transport speed distribution, nano-TiO2film deposition rate and different substances’enthalpy distribution can be simulated by defining arithmetic. the relative properties of carrier gas and precursors, the function on nano-TiO2film deposition rate, reaction mechanism and boundary conditions in the software Fluent. The function on transportation speed of gaseous mixture, the function on deposition rate of nano-TiO2film and the parametric thermodynamics model can be validated by the simulation results in the Fluent. And the value of thermodynamics on nano-film preparation reaction per unit time can also be obtained according to established function on deposition rate of nano-TiO2film and thermodynamic quantities of the reaction. The ratio of the available energy on chemical reaction to the totally energy consumption of equipments can be calculated by comparing the available energy per unit time with equipments’energy consumption; at the same time, we can get the utilization of raw materials by using the deposition rate function of nano-TiO2film and mass flow of precursor.