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New applications with time-dependent thermochemical simulation

Abstract

A new method (RATEMIX) to calculate multicomponent chemical reaction mixtures as a series of sequential thermochemical states was recently introduced. The procedure combines multicomponent thermodynamics with chemical kinetics and may be used to simulate the multicomponent reactors as a thermochemical natural process. The method combines the desired reaction rates sequentially with constrained Gibbs energy minimization. The reactant concentrations are determined by the experimental (Arrhenius) rate laws. During the course of the given reaction the subsequent side reactions are supposed to occur reversibly. At every sequential stage of the given reaction the temperature and composition of the reaction mixture are calculated by a thermodynamic subroutine, which minimizes the Gibbs energy of the system and takes into account the heat transfer between the system and its surroundings. The extents of reaction are included as algorithmic constraints in the Gibbs energy minimization procedure. Initially, the reactants are introduced to the system as inert copies to match both the mass and energy balance of the reactive system. During the calculation the copies are sequentially interchanged to the actual reactants which allows one to simulate the time-dependent reaction route by using the thermochemical procedure. For each intermediate stage, the temperature and composition are calculated and  More>>
Authors:
Koukkari, P; [1]  Laukkanen, L; [2]  Penttilae, K [3] 
  1. VTT Chemical Technology, Espoo (Finland)
  2. VTT Automation, Espoo (Finland)
  3. Kemira Engineering Oy, Helsinki (Finland)
Publication Date:
Dec 31, 1996
Product Type:
Conference
Report Number:
TKK-V-B117; CONF-9606318-
Reference Number:
SCA: 400201; 420400; PA: FI-97:003306; EDB-97:062347; SN: 97001773812
Resource Relation:
Conference: 3. colloquium on process simulation, Espoo (Finland), 11-14 Jun 1996; Other Information: PBD: 1996; Related Information: Is Part Of The 3rd colloquium on process simulation. Proceedings; Jokilaakso, A. [ed.]; PB: 359 p.
Subject:
40 CHEMISTRY; 42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; CHEMICAL REACTORS; THERMODYNAMICS; CHEMICAL REACTION KINETICS; COMPUTERIZED SIMULATION; EQUILIBRIUM
OSTI ID:
464569
Research Organizations:
Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Materials Processing and Powder Metallurgy
Country of Origin:
Finland
Language:
English
Other Identifying Numbers:
Other: ON: DE97740683; ISBN 951-22-3092-5; TRN: FI9703306
Availability:
OSTI as DE97740683
Submitting Site:
FI
Size:
pp. 361-369
Announcement Date:

Citation Formats

Koukkari, P, Laukkanen, L, and Penttilae, K. New applications with time-dependent thermochemical simulation. Finland: N. p., 1996. Web.
Koukkari, P, Laukkanen, L, & Penttilae, K. New applications with time-dependent thermochemical simulation. Finland.
Koukkari, P, Laukkanen, L, and Penttilae, K. 1996. "New applications with time-dependent thermochemical simulation." Finland.
@misc{etde_464569,
title = {New applications with time-dependent thermochemical simulation}
author = {Koukkari, P, Laukkanen, L, and Penttilae, K}
abstractNote = {A new method (RATEMIX) to calculate multicomponent chemical reaction mixtures as a series of sequential thermochemical states was recently introduced. The procedure combines multicomponent thermodynamics with chemical kinetics and may be used to simulate the multicomponent reactors as a thermochemical natural process. The method combines the desired reaction rates sequentially with constrained Gibbs energy minimization. The reactant concentrations are determined by the experimental (Arrhenius) rate laws. During the course of the given reaction the subsequent side reactions are supposed to occur reversibly. At every sequential stage of the given reaction the temperature and composition of the reaction mixture are calculated by a thermodynamic subroutine, which minimizes the Gibbs energy of the system and takes into account the heat transfer between the system and its surroundings. The extents of reaction are included as algorithmic constraints in the Gibbs energy minimization procedure. Initially, the reactants are introduced to the system as inert copies to match both the mass and energy balance of the reactive system. During the calculation the copies are sequentially interchanged to the actual reactants which allows one to simulate the time-dependent reaction route by using the thermochemical procedure. For each intermediate stage, the temperature and composition are calculated and as well numerical estimates of the thermodynamic functions are obtained. The method is applicable in processes where the core thermodynamic and kinetic data of the system are known and the time-dependent heat transfer data can either be measured or estimated by calculation. The method has been used to simulate e.g. high temperature flame reactions, zinc vapour oxidation and a counter-current rotary drum with chemical reactions. The procedure has today been tested with SOLGASMIX, CHEMSAGE and HSC programs. (author)}
place = {Finland}
year = {1996}
month = {Dec}
}