Page 212 - Dust Explosions in the Process Industries
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I84  Dust Explosions in the Process Industries


            development on the basis of a seismicrecording of the explosion by the State Station of
            Seismology, located only 17 km from the Harbin Linen Textile Plant.


            2.9.2
             EXPLOSION INITIATION AND DEVELOPMENT, SCENARIO 1

            Figure 2.24 illustrates the 13,000m2spinning section through which the explosion swept
             and the possible locations and sequence of  the nine successive explosions that consti-
             tuted the event according to Xu Bowen (1988) and Xu Bowen et al. (1988). These work-
             ers based their reconstructionof the explosionon three independent elements  of evidence.
             First, they identified the location of the various explosion sites throughout the damaged
             plant. Second, they ranked the relative strengths  of the local explosions by studying the
             extent and nature of the damage. Third, they arranged the various local explosions in time
             by means of the relative strengths of the nine successive explosions, identified by decod-
             ing the seismic recording of the event.
               Figure 2.25(A) shows a direct tracing of the amplitude-modulatedseismic signal actu-
             ally recorded 17km from the explosion site. Figure 2.25(B) shows the sequenceof nine
             energy pulse impacts on the earth at the location of Harbin Linen Textile Plant, deduced
             from the signal in Figure 2.25(A). Figure 2.25(C) finally shows the theoretical predic-
             tion of  the seismic signal to be expected from the sequence of  explosions in Figure
             2.25(B). The agreement between the (A) and (C) signals is striking, which supports the
             validity of the energy impact pulse train (B).













                                                         --_____  J


                                                                           UNDERGROUND
                                          NOT DIRECTLY  INVOLVED
             CENTRAL  DUST




                                                     LINEN FLAX STORES
                         -  k               APPROX.  100 rn          d

             Figure 2.24   The 12,000 m2spinning section of the Harbin Linen Textile Plant, Peoples Republic of
             China, that was afflicted with a catastrophic dust explosion on March  15, 1987. Numbered circles,
             ovals, and triangles indicate location and sequence of a postulated series of nine successive explo-
             sions (From Xu Bowen et al.,  1988).
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