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Inorganic Nanofiltration Membranes for Separation Refining Processes


The objective of the project is to develop inorganic
zircon nanofiltration membranes and processes for the
separation of organic / organic mixtures in process
streams encountered in the oil refining industry.
Although there is a need to improve separation efficiency
in other similar refining process streams (dewaxing,
deasphalting, etc), the project will, specifically,
address the separation of organic solvents (mostly
furfural) from extracts (average molecular weight, 500),
produced in the manufacturing of lubricating base oils,
where solvents (furfural, NMP,ets) extraction is applied
to improve the their viscosity properties. In these
processes, solvent recovery is energy intensive and the
main contributor to the operating costs. All this is
pushing the development of alternative separation
processes energetically more efficient, safer and
cleaner, membrane processes are among the few fulfilling
those characteristics.
In the last decade the development of organic membranes
with special characteristics have largely opened the
field of applications for membrane separations of organic
mixtures (Exxon, Texaco). However, organic membrane
present problems of stability against temperature and
organic solvents. To overcome those limitations,
inorganic membranes, being more temperature stable and
chemically inert, will enhance the range of application
allowing, also, higher permeate fluxes due to
temperature decrease of the value of physical properties
controlling them like density and viscosity and
facilitating the backwash of the membranes.
The project will address the development of membranes
needed for such applications. Research will be carried
out to develop inorganic zircon nanofiltration membranes
with cut off between 200 and 400 Daltons, intrinsically
selective towards the solvent mentioned above and capable
of operating in the temperature range of 150 C to 300 C
in aggressive organic regimes. The minimum objectives
figures for selectivities, permeate flux rates and
membrane duration are 98%, 80 kg/m2h and 4 years,
respectively, which are considered necessary for the
process to be economically feasible.
Following the development and laboratory evaluation of
the membranes, modules containing 1m2 of membrane area
will be test by studying their performance with actual
process streams. The project will also include a computer
based model for the design of nanofiltration processes
and its integration with conventional separation
processes. Finally, the project will establish the
economic perspectives of the membrane process in respect
to alternative and competitive separation processes.
The proposers anticipate that economic benefits will be
accrued to both membranes producers and end users. Only
for the application to studied, and assuming a European
market penetration of 25%, the expected benefits (savings
of energy and solvents) are closed to 8 MECU's/year. The
estimated PayBack period for new nanofiltration plant
investments is 2.1 years. A European membrane market
closed to 10.000 m2 could be expected in ten years, that
means more than one third of the whole worldwide mineral
membrane surface at present time. Thus, the project will
improve the European industry competitiveness against
Japan and, specially, the USA in this field.
The consortium presenting this proposal comprises
membrane producers, engineering designers and end users
with complementary interests in refining processing as
well as the contribution of Universities specialised in
membrane characterisation and process simulation.


Repsol Petróleo SA
278-280,P De La Castellana
28046 Madrid

Participants (4)

ADW Ingenieurbüro für Umweltschutz- und Industrieabwassetechnik GbR
27,Schorndorfer Strasse 27
70736 Fellbach
Orelis S.A.
5,Chemin Du Pilon
01703 Saint Maurice De Beynost
S/n,avenida Julian Claveria S/n
33071 Oviedo
Route De Narbonne 118 Ura 192
31062 Toulouse