Aug 28, 2015- The Tianjin chemical warehouse explosion was one of the world’s worst chemical and warehouse related accidents ever seen. While speculation is rife about the cause and all sorts of theories are floating around, we have formulated a likely sequence of events scenario about how it may have happened. Of course, this is pure speculation. Only a proper investigation can come to a definitive conclusion, nevertheless, we can always have a hypothesis.
It appears that there was a minor fire which broke out in the same warehouse in another section, or in a nearby area that was in close proximity to it. Firefighters had been called and they were busy dousing the fire, with water. Probably that may have been the appropriate method of dousing, for that particular fire. Unfortunately and unbeknownst to the firemen, there was another chemical stored nearby, which may have got also drenched in the water, maybe due to high pressure jets penetrating the packaging. This chemical might have been Calcium Carbide. Now Calcium Carbide reacts violently with water and produces Acetylene, which is highly explosive. In fact it gets classified in Group A of the NEC Hazardous Area Classification and Group IIC of the IEC/CENELEC standards (Group IIC has highly explosive gases such as Hydrogen in it). Now if a large quantity of Acetylene was released it made a bad situation even worse. The initial small fire became an ignition source for this large quantity of Acetylene that became a huge explosion. Once something like this happens, there are several combinations of possibilities. Under such conditions some of the other chemicals may have reacted with each other or with the byproducts of the earlier reactions, leading to unpredictable outcomes.
Until we know more details, this seems to be a possible chain of events that occurred.