The Emergency Relief of Chemical Reactors

This thesis is a report of research into the emergency
relief of chemical reactors. The work determines the UK
view of the AIChE DIERS project, and compares and contrasts
the DIERS methodology with other methods available to the
UK chemical industry.
The work consists of investigations on three
experimental reactive systems, to assess the sensitivity,
practical limitations, reliability and, the reproducibility
of data from the vent sizing package with regard to the
determination of the vent size requirements of chemical
reactors. The work also compares the vent sizing package
with other existing "state of the art" calorimetric methods
for determining runaway reaction data.
As a result of the investigation a cheaper alternative
instrument, known as the Reactor Vent Sizing Calorimeter
(RVSC), for medium and small sized UK chemical
manufacturers has been developed and tested for two example
reactive systems.
The results from these systems have been compared with
those determined for the "Vent Sizing Package" and, other
existing calorimetric methods to assess the suitability of
the new instrument for vent sizing requirements.
The main conclusions drawn in this thesis are:-
a) The "Vent Sizing Package" has several design and
operational drawbacks which lead to wide variations in the
data obtained and the subsequent determined vent sizes.
b) Traditional vent sizing methods seldom consider
the existence of two-phase vent line flow and invariably
provide vent sizes insufficient to deal with its
occurrence.
c) The newly developed alternative instrument, RVSC,
is cheaper, easier to operate and easier to maintain when
compared to the existing "Vent Sizing Package" and can be
considered as a viable alternative to existing commercial
vent sizing packages.
a) The RVSC is capable of studying fast reactions
and those which produce large amounts of non-condensible
gases.
e) The repeatability of the runaway data is improved
with the RVSC.
£) Reactions involving addition of reagents can be
studied with the new RVSC as well as investigation of
inhibition and quenching.