Molecular weight of MMA is about 100, which is over 3x that of atmospheric constituents, so it is likely to hang close to the ground until mixing dilutes it. If it comes out hot, that may be enough to create a rising plume. Permissible/recommended exposure level is 100 ppm, so there needs to be a dilution factor of 10,000. Pay attention to the prevailing wind. I don't know enough to hope that a Santa Ana may show up. Good luck and God bless.
Hopefully they can cool the tanks enough to keep it from going into thermal runaway. The boiling point I believe is 101 degrees C. Last I heard the internal MMA temp was at 90 degrees C. Their goal is to let it catalyze slowly until the reaction peters out. No explosion and no leak. Not sure how long that process is estimated to take however. Haven't heard anyone talk about it so far. I believe the plume path is calculated to go north of the plant - at least at the current moment and subject to change. The air temp tomorrow is supposed to be about 70 degrees for a couple of days and then drop into the 60's for a few more days before it climbs back up into the mid to high 70's later in the week. That should help versus 80 plus weather. Wind speeds are estimated to be from about 2 to 12mph out of WSW and South.
Good luck for all. If they are letting the tank contents fully polymerize, that would suggest the tanks are goners, being full of solid acrylic. Interesting disposal problem. Air temp at 70 F is 21 C, so the ambient environment will cool the tanks to some extent.
I used to think of this or styrene as being interesting for rocket fuels, but was wary of polymerization.
I think at this moment a tank full of acrylic is the least of their worries. Still haven't heard why the polymerization started in the tank. The bulge was seen and the heat went up. When this event is finally over I have no doubt they will figure out what happened.
Apparently the polymerization reaction is exothermic, so it is just waiting to happen. It could have been provoked by some material in the tank that functioned as a catalyst. Or they let the storage temperature drift upward. Some of the things I read suggested that the new owner of the facility might not have been entirely on top of the safety aspects of MMA storage.
A long history without problems can lead to fatal complacence. I lived in a town that had a pulp and paper mill. They decided to install storage tanks for liquid chlorine used to bleach the paper. Fast forward 20 or so years. The mill had been shut down and was being dismantled. The liquid chlorine tanks were empty; when they were in use, the contents were cold enough to create a constant layer of ice on the tank wall. So, on a nice sunny day, some workers decided to sit on some lumber piled up next to the tanks to have their lunch. One worker in mid-sandwich leaned back against the tank wall...and fell through it, backward into the tank. The wall had been corroded paper-thin. All that was holding it together during its lifetime was the ice layer.
Molecular weight of MMA is about 100, which is over 3x that of atmospheric constituents, so it is likely to hang close to the ground until mixing dilutes it. If it comes out hot, that may be enough to create a rising plume. Permissible/recommended exposure level is 100 ppm, so there needs to be a dilution factor of 10,000. Pay attention to the prevailing wind. I don't know enough to hope that a Santa Ana may show up. Good luck and God bless.
Hopefully they can cool the tanks enough to keep it from going into thermal runaway. The boiling point I believe is 101 degrees C. Last I heard the internal MMA temp was at 90 degrees C. Their goal is to let it catalyze slowly until the reaction peters out. No explosion and no leak. Not sure how long that process is estimated to take however. Haven't heard anyone talk about it so far. I believe the plume path is calculated to go north of the plant - at least at the current moment and subject to change. The air temp tomorrow is supposed to be about 70 degrees for a couple of days and then drop into the 60's for a few more days before it climbs back up into the mid to high 70's later in the week. That should help versus 80 plus weather. Wind speeds are estimated to be from about 2 to 12mph out of WSW and South.
Good luck for all. If they are letting the tank contents fully polymerize, that would suggest the tanks are goners, being full of solid acrylic. Interesting disposal problem. Air temp at 70 F is 21 C, so the ambient environment will cool the tanks to some extent.
I used to think of this or styrene as being interesting for rocket fuels, but was wary of polymerization.
I think at this moment a tank full of acrylic is the least of their worries. Still haven't heard why the polymerization started in the tank. The bulge was seen and the heat went up. When this event is finally over I have no doubt they will figure out what happened.
Apparently the polymerization reaction is exothermic, so it is just waiting to happen. It could have been provoked by some material in the tank that functioned as a catalyst. Or they let the storage temperature drift upward. Some of the things I read suggested that the new owner of the facility might not have been entirely on top of the safety aspects of MMA storage.
A long history without problems can lead to fatal complacence. I lived in a town that had a pulp and paper mill. They decided to install storage tanks for liquid chlorine used to bleach the paper. Fast forward 20 or so years. The mill had been shut down and was being dismantled. The liquid chlorine tanks were empty; when they were in use, the contents were cold enough to create a constant layer of ice on the tank wall. So, on a nice sunny day, some workers decided to sit on some lumber piled up next to the tanks to have their lunch. One worker in mid-sandwich leaned back against the tank wall...and fell through it, backward into the tank. The wall had been corroded paper-thin. All that was holding it together during its lifetime was the ice layer.