paraffin wax deposition and fouling

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8. ICOi’NDATTCNS
It is recommended that further work should be done on fouling of
heat exchanger tubes to produce date for evaluation of the various
fouling models.
Any work using the present fouling studies apparatus
should include friction factor measurements.
The apparatus would be
improved if the 24 hour fluctuations of flowrate and temperature arising
in the cooling water mains, could be eliminated.
Considerable scope exists for further work using the deposition
apparatus.
It is recommended that a high melting point paraffin wax be
used in a close boiling range solvent.
The wax determination method
should be improved.
Extensive data on one solution at different
concentrations, temperatures and flowrate would allow the evaluation
of the deposition and fouling models that have been proposed, particularly
to demonstrate how the initial deposition rates depend on fiowrate.
Some
fundamental problems of interest in fouling include; the
behaviour of small particles in boundary layers, the effect of cooling
and shear stresses on cloud and pour points, composition and crystallisa—
tion of particles and deposits, shape and size of partIcles and the
adhesion properties to smooth and rough surfaces.
Understanding of these prbblerns would help explaining the character
istic buildup and removal of paraffin wax deposits.