DESIGNING A SEQUENTIAL-MODULAR
STEADY-STATE SIMULATOR FOR KRAFT
RECOVERY CYCLE EVAPORATIVE SYSTEMS
Authors: Márcio R. Vianna Neto1,2, Marcelo Cardoso1
, Ekaterina Sermyagina2
, Esa K. Vakkilainen2
, Eder D. Oliveira1
1 Federal University of Minas Gerais (UFMG). Brazil
2 Lappeenranta-Lahti University of Technology LUT. Finland
O PAPEL vol. 83, N.o 3, pp. 72 - 77 - MAR 2022
ABSTRACT
A sequential-modular process simulator was developed for
simulating Kraft recovery cycle evaporation plants under steadystate conditions. The simulation engine was written in C++ and
has been made freely available to the scientific and technical
communities. The engine included subroutines for ordering,
partitioning, and tearing flowsheets, as well as for converging
torn flowsheet streams. In this paper, these core subroutines
are described. Evaporator calculations are based on steam table
correlations and black liquor enthalpy correlations described
in literature. The numerical method used for converging torn
streams in this implementation was the well-known Wegstein
Method. Five multiple-effect counter-current evaporator
scenarios, ranging from 3 to 7 effects, were used to profile
the simulator. The simulator was shown to be robust enough
to be used for simulating evaporator arrangements that are
typically found in the pulp and paper industry. The robustness
of convergence found in the tested scenarios suggests that the
simulator could be extended to accommodate more complex
systems. The simulator converged quickly to all solutions,
suggesting that it may be used for performing optimization of
evaporative 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: +55-31-34091735
Email: marciorvneto@ufmg.br