DESIGNING A SEQUENTIAL-MODULARSTEADY-STATE SIMULATOR FOR KRAFTRECOVERY CYCLE EVAPORATIVE SYSTEMS
Authors: Márcio R. Vianna Neto1,2, Marcelo Cardoso1, Ekaterina Sermyagina2, Esa K. Vakkilainen2, Eder D. Oliveira11 Federal University of Minas Gerais (UFMG). Brazil2 Lappeenranta-Lahti University of Technology LUT. Finland
O PAPEL vol. 83, N.o 3, pp. 72 – 77 – MAR 2022
ABSTRACTA sequential-modular process simulator was developed forsimulating Kraft recovery cycle evaporation plants under steadystate conditions. The simulation engine was written in C++ andhas been made freely available to the scientific and technicalcommunities. The engine included subroutines for ordering,partitioning, and tearing flowsheets, as well as for convergingtorn flowsheet streams. In this paper, these core subroutinesare described. Evaporator calculations are based on steam tablecorrelations and black liquor enthalpy correlations describedin literature. The numerical method used for converging tornstreams in this implementation was the well-known WegsteinMethod. Five multiple-effect counter-current evaporatorscenarios, ranging from 3 to 7 effects, were used to profilethe simulator. The simulator was shown to be robust enoughto be used for simulating evaporator arrangements that aretypically found in the pulp and paper industry. The robustnessof convergence found in the tested scenarios suggests that thesimulator could be extended to accommodate more complexsystems. The simulator converged quickly to all solutions,suggesting that it may be used for performing optimization ofevaporative systems.Keywords: simulator, steady state, evaporator, black liquor,sequential-modular
Corresponding author: Vianna Neto, M. R. Lappeenranta-Lahti University of Technology / Federal University of Minas Gerais(UFMG). Av. Pres. Antônio Carlos, 6627 – Pampulha. Belo Horizonte – MG – Brazil – 31270-901. Phone: +55-31-34091735Email: [email protected]