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... Chemical process modeling is the basis for research and applications in related fields. With the development of industrial informatization, data-driven process modeling techniques are increasingly applied in chemical processes, helping to obtain more accurate results with less model development costs. However, due to the high-dimensional nonlinear characteristics of most chemical processes, proble ...
... This paper shows how the problem of simulation and design of integrated direct rotary dryer and cooler can be solved in an algorithmic way. In the last few decades dryers and coolers are often assembled in one unit to save space and/or energy (process integration). Several types of construction of such units have been proposed. Since the coupling between models describing both parts of such a unit ...
... Incorporating (operational) flexibility into process design has been a key approach to cope with uncertainties. The increasing penetration of renewables and the need for developing new low-carbon technologies will increase the demand for flexibility in chemical processes. This paper presents a state-of-the-art review focusing on the origin, definition, and elements of flexibility in the chemical e ...
... In recent years, dimethylphenol has played an important role in industrial production. The demand and application of dimethylphenol will increase greatly with the continuous advancement of the internationalization process. Solid-liquid equilibrium (SLE) is fundamental for the separation process design, the SLE data of dimethylphenol plays an important role in designing the melting and crystallizat ...
... In this work, we demonstrate that tracing the vapor–liquid equilibria for binary mixtures also includes all the information needed to obtain the three-phase line if one is present. This simple observation serves as a launching point for calculation of the liquid–liquid equilibrium and three-phase equilibria, even when one component is supercritical. We close with the demonstration of the automatic ...
... Ensuring asymptotic stability of the Nonlinear Model Predictive Control formulation is not trivial. Stabilizing ingredients such as terminal cost term and terminal set are necessary. Approaches available in the literature provide minimal degrees of freedom for the terminal set characterization. The current work presents a linear quadratic regulator based approach, which provides large degrees of f ...
... The s-SAFT-γ Mie equation of state (EoS) proposed by Shaahmadi et al. [J. Chem. Phys.2021, 154, 244102, DOI: 10.1063/5.0048315] features a modification to SAFT-γ Mie’s chain term, which enables differentiation between the properties of structural isomers. This work now extends structural (s)-SAFT-γ Mie to the (CH₂OH) functional group in linear primary alcohols. s-SAFT-γ Mie’s descriptions of the p ...
processdesign, etc ; cathodes; cations; electrochemistry; Show all 4 Subjects
Abstract:
... Layered hydrated vanadates have been regarded as promising cathode materials for Zn-ion batteries, while their electrochemical properties have been proved to be highly related to the species of the interlayer cations. However, because the single species of the interlayer cation can hardly endow the layered materials with comprehensively favorable properties, the introduction of multiple interlayer ...
processdesign, etc ; anisotropy; cathodes; electrolytes; Show all 4 Subjects
Abstract:
... The promising LiNi₀.₉₂Co₀.₀₅Al₀.₀₃O₂ (NCA) cathode materials have become attractive recently for high-energy-density lithium-ion batteries (LIBs), but they suffer from severe capacity fade due to structure degradation and interface instability. Herein, a dual-modification strategy of Nb doping and Li₄SiO₄ coating is employed to consolidate the surface and crystal stability of NCA. The Nb doping co ...
... A new model for correlating self-diffusion coefficients is proposed here. It is based on the entropy scaling concept and makes it possible to quantitatively estimate self-diffusion coefficients in any fluid state (subcritical gas and liquid as well as supercritical states). A general relationship between a dimensionless form of the self-diffusion coefficient and a function of the Tv-residual entro ...
... Data-driven methods have been widely used in process monitoring and fault detection areas. Despite that, most of these data-driven approaches are extremely specific, where the developed models can only be applied in the given process with the selected variables. The lack of generalization potentially limits its applications. This work mainly focuses on developing a model with better generalization ...
... Crystal size plays an essential role in the performance of polymers. Generally, direct processing of common spherulites into nanocrystals (NCs) is hardly applied since polymer spherulites always shape into fibrous crystals and are hard to flow again. In this study, polylactide (PLA) lamellae of spherulites are first diluted by amorphous PLA. Then, PLA NCs are constructed in situ by intense stress, ...
... Despite the advancement in simulation technology, a great challenge for unconventional resources is relevant to the correct representation of phase equilibria in nanopores and the effective implementation of involved models. A novel phase equilibrium calculation framework based on the successive substitution (SS)–Newton–Trust-Region (TR) method, coupled with critical property shifts and capillary ...
processdesign, etc ; capacitance; chemistry; convection; dispersibility; Show all 5 Subjects
Abstract:
... A novel measurement system for radial particle mixing in annular fluidized beds is designed on the basis of the capacitance probe method. Mixing parameters at different radial positions are acquired. The effects of the convection/diffusion mechanism on radial mixing are analyzed individually. It is found that the governing mechanism of mixing at the axial line is convection; meanwhile, diffusion i ...
processdesign, etc ; chemistry; mathematical theory; models; Show all 4 Subjects
Abstract:
... Graph theory provides a convenient framework for modeling and solving structured optimization problems. Under this framework, the modeler can arrange/assemble the components of an optimization model (variables, constraints, objective functions, and data) within nodes and edges of a graph, and this representation can be used to visualize, manipulate, and solve the problem. In this work, we present ...
processdesign, etc ; adsorption; desorption; surface area; Show all 4 Subjects
Abstract:
... In this paper, a series of Pd/CeO₂ catalysts prepared by different synthesis routes and showing different morphological and textural properties have been investigated for passive NOₓ adsorption (PNA) applications. The results obtained by NOₓ adsorption/desorption tests demonstrated that NOₓ storage capacity and NOₓ storage efficiency of Pd/CeO₂ materials depend strictly on their surface area, wher ...
... Simple models are developed for realistic operation modes of periodic separation. The models comprise instantaneous, simultaneous, and sequential draining. Using our models, the influence of a finite drainage time on separation performance is investigated. Linear case systems are modeled for stationary profiles for both simultaneous and sequential liquid drainage. Performance measures, such as tra ...
processdesign, etc ; chemistry; geometry; industry; polymers; Show all 5 Subjects
Abstract:
... In the blown film industry, the nonuniformity in films has been one of the most important problems, and the existing structures of blown films dies have many disadvantages, such as long thermal process and complex structure. This work proposes a novel flow channel structure of blown film die via theoretical modeling and verified by numerical simulations. The results show that the new structure is ...
processdesign, etc ; electrons; liquids; turbulent flow; Show all 4 Subjects
Abstract:
... A Eulerian–Eulerian computational fluid dynamics approach is used in conjunction with appropriate auxiliary models for turbulence and solid dynamic properties to study the complex turbulent flow of particle–liquid suspensions in a horizontal pipe. Numerical simulations of the detailed flow field are fully and successfully validated using a unique experimental technique of positron emission particl ...
processdesign, etc ; adhesion; crosslinking; deformation; epoxides; Show all 5 Subjects
Abstract:
... Epoxy adhesives that combine flexibility, high-temperature adhesion property, and medium–low-temperature curing ability are an urgent need in the microelectronic device era. Unfortunately, it is still a challenge so far. In this context, two kinds of curing agents are combined to construct homogeneous rigid–flexible crosslinking networks via the stepwise curing method for preparing an epoxy adhesi ...