PDF Publication Title:
Text from PDF Page: 010
Processes 2022, 10, 812 10 of 19 In the SD model approach, the PDAEs of the adsorption process is converted into differential algebraic equations (DAEs). This method only discretizes the space domain and uses the ode solver to solve in the time domain. The cyclic steady state of the PSA process is reached by switching the boundary conditions related to different steps in the cycle, which robustly processes simulation and optimization. The optimal decision value obtained by optimization is the same as the simulated process performance, and it is easier to initialize the convergence region than with the CD model. In the CD model approach, the time domain and spatial domain are discretized simultaneously. The method directly couples the PDAEs system with the optimization problem, and the model equation is solved only once in the optimal state, avoiding too much computation work to obtain the intermediate solution and achieving a better numerical- computation ability and robustness. Nilchan et al. [64] first proposed the CD method by using the orthogonal configuration method to discretize the time domain, and the finite difference method to discretize the space domain. The computational costs of time integration were fully eliminated but this relied on the iteration of nonlinear algebraic equations. Calvin Tsay et al. [65] formulated a new set of pseudo-transient simulation and optimization principles for dynamic process models based on discretizing the temporal domain and spatial domain simultaneously. In previous work, a nonlinear programming model such as the quadratic program- ming (QP) and sequential quadratic programming (SQP) algorithms are commonly used in for the PSA optimization based on the SD model. In order to solve large-scale nonlinear programming problems, which have a large number of equationally constrained equations but relatively low degrees of freedom, the reduced-space SQP (r-SQP) algorithm is pro- posed. The r-SQP can greatly reduce the amount of calculation and storage capacity of the optimization process through a spatial-decomposition technique that solves the process system in zero space, with relatively small degrees of freedom [31]. Currently, the algorithm has been successfully applied in nitrogen/methane separation, biogas upgrading, carbon capture, and other processes. Sun et al. [66] employed the state-of-the-art reduced space successive quadratic programming (r-SQP) optimization algorithm to find the optimal values of decision variables with additional constraints for N2/CH4 separation, which took nearly 64 h. Ding et al. [67] proposed a generic optimization framework, as shown in Figure 3. It contained the discretization and solution of the partial differential equa- tions, the sensitivity of the decision variable, the judgment of CSS, and the choice of the optimization algorithm. 3.1.3. Surrogate Model In order to simplify the computation of reaching CSS and reduce the computational consumption in the optimization process on the basis of the accuracy of the model, re- searchers proposed the surrogate model to replace the detailed model. The surrogate model generated from data-driven black-box functions, the central problem of which is learning to establish an input–output relationship that is as accurate and simple as possible from data obtained from simulations or experiments, instead of solving the equations. This model investigates the effect of operation parameters (valve, feed flow rate, adsorption time) on objective functions (purity, recovery, productivity, energy consumption) through a large number of experimental and simulation results.PDF Image | Numerical Research on the Pressure Swing Adsorption Process
PDF Search Title:
Numerical Research on the Pressure Swing Adsorption ProcessOriginal File Name Searched:
processes-10-00812-v2.pdfDIY PDF Search: Google It | Yahoo | Bing
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
Heat Pumps CO2 ORC Heat Pump System Platform More Info
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |