Page 130 - Dust Explosions in the Process Industries

Dust Explosions: An Overview 103

Figure 1.1 18 A pressure sensor of the membrane type used for activating automatic dust explo-
sion suppression systems. The diameter of the membrane is about 100 mm (Courtesy of Kidde-
Graviner, Colnbrock, United Kingdom).

mounting the unit at any desired location. However, regular inspection and testing of
power supply and the like is required. This unit was originally designed for using halon
as suppressant, but transfer to powder suppressants is probably not too difficult.
The status on explosion suppression technology has been reviewed repeatedly in the
literature. A fairly early paper discussing large-scale experimental research in France in
the late 1960s was presented by Winter (1970). Bartknecht (1978) has a comprehensive
discussion of extensive research in the Federal Republic of Germany and Switzerland
in the 1970s. A summary covering similar evidence was given by Scholl(l978). Singh
(1 979) summarized theoretical and experimental work from various countries including
the United Kingdom, United States, Federal Republic of Germany, and Switzerland.
Moore (198 1) discussed the results of his own comprehensive experimental and theo-
retical research, which resulted in a basis for systematic design of industrial suppres-
sion systems. He introduced the concept of critical mass M, of suppressant that is just
sufficient for suppressing the flame when being evenly distributed throughout the