Session 36: Unit Operations
Chair:
Argimiro Resende Secchi
Departamento de Engenharia Química
UFRGS
BEHAVIOR ANALYSIS OF A SIMULATED MOVING BED UNIT IN ENANTIOMERS SEPARATION - TRANSIENT FLOW
Eduardo Alberto Borges da
Silva ?eduardo@labsin.ufsc.br
Selene M. A. Guelli Ulson
de Souza ?selene@labsin.ufsc.br
Universidade Federal de
Santa Catarina, Departamento de Engenharia Química e Engenharia
de Alimentos, LABSIN - Laboratório
de Simulação Numérica de Sistemas Químicos
88.040-900, Florianópolis,
SC, Brasil
The transient mathematical model of a simulated moving bed unit is presented. The model considers the switching of the inlet and outlet points of the fluid streams of the unit at each switching time. It is considered the plug flow with axial dispersion to fluid phase. It is used the linear driving force approximation to related the mass transfer between the fluid and solid phases. It is simulated the chromatography separation of bi-naphtol enantiomers and analyzed the transient behavior of a simulated moving bed unit with different subsections numbers in this separation. In order to resolve the differential equations of the model it is utilized the finite volume method with the WUDS scheme. It is analyzed the influence of the overall mass transfer coefficient on performance of the simulated moving bed in the separation process.
Keywords: Simulated moving
bed, Modeling, Transient
ISABEL C. TESSARO
KEIKO WADA
EDUARDO G.F. FERREIRA
Department of Chemical Engineering,
Federal University of Rio Grande do Sul 90040-040, Porto Alegre-RS-Brazil
Acid whey is a liquid byproduct
of cottage cheese manufacturing and it is considered an important source
of proteins that could be used for human consumption. The effective utilization
of the large volumes of whey produced represents a significant challenge
to the dairy industry. The most promising process to recover whey proteins
is ultrafiltration. The main advantage of using ultrafiltration as a method
to increase the aggregate value of cheese whey is that this process allows
a variation in the concentration relationship among its several components.
This work presents a study of the concentration characteristics of acid
whey by means of ultrafiltration. The influence of several parameters,
such as molecular weight cut off, spacer geometry, feed composition on
the retention and permeate flux behavior have been investigated. In order
to chose a membrane configuration with a proper retention and good operating
conditions the following parameters have been analyzed during the UF experiments:
hydraulic permeability, permeate flux, the total concentration of solids
and protein concentrations. The experiments were performed in a UF pilot
equipment, using three commercially spiral wound modules with two different
molecular weight cut-of and two different spacer geometry. The present
study gives a good insight on the interactions within membrane filtration
in the concentration of acid whey, and a real evaluation of the possibility
of using UF to concentrate acid whey in the local dairy industries.