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Utilization of CO2 to produce value-added chemicals is a promising approach to mitigate greenhouse gas emissions. In this work, a new process for the conversion of CO2 to dimethyl carbonate (DMC) and ethylene glycol (EG) was rigorously simulated and assessed in term of the technical performance and the environmental impact. The proposed model involves the conversion of CO2 catalyzed by ionic liquid-based catalysts, the reactive distillation with the reaction kinetics model, the pressure-swing distillation with rigorous phase equilibrium equations, and complex material-energy nexus between each unit. The results show that the carbon utilization efficiency of this process reaches 99% and the negative CO2 emission is 0.14 ton CO2/ton product achieving CO2 reduction. The green degree value of the entire process is 176.30 gd/h indicating that this new process can be evaluated as an environmental friendly process. Additionally, the retrofitted heat exchanger network designed via the pinch technique achieves 48.70% saving in heating utility consumption and increasing the green degree by 193.89 gd/h.

Friction is quite common and inevitable in physical environments. During the process of friction, vibration and collision will bring large deviations to identification results. In this paper, friction process with the influence of vibration and collision as well as data collection are implemented. In terms of friction model, according to the theory of Fourier series, we can introduce sine filter terms into friction model to eliminate influence of vibration and collision on parameter identifications. To get a much more accurate and efficient algorithm of identification, we embed simulated annealing operator into a genetic algorithm to take the advantages of both genetic algorithm and simulated annealing algorithm. With the hybrid algorithm, the identification results of friction process under the influence of the vibration and collision can be determined effectively.