NARRATOR: FEBRUARY 8, 2017: THE PACKAGING CORPORATION OF AMERICA'S DERIDDER, LOUISIANA PULP AND PAPER MILL. AN EXPLOSION OCCURRED DURING HOT WORK ACTIVITIES KILLING THREE CONTRACT WORKERS AND INJURING SEVEN OTHERS. THE DERIDDER MILL PRODUCES CONTAINERBOARD THAT IS USED IN PRODUCTS SUCH AS BOXES AND CARDBOARD DISPLAYS. THE CONTAINERBOARD IS MADE FROM PULP PRODUCED AT THE FACILITY. DURING THE PROCESS OF CREATING PULP, VAPORS ARE GENERATED. THESE VAPORS, WHICH CONTAIN WATER, TURPENTINE, AND VARIOUS SULFUR COMPOUNDS, ARE COLLECTED AND SEPARATED. TO SEPARATE THE VAPORS, THEY FIRST
ENTER A TURPENTINE-STRIPPING COLUMN. THERE, MOST OF THE TURPENTINE IS
REMOVED AND SENT TO A CONDENSER. THE REMAINING VAPORS IN THE STRIPPER CONDENSE TO A LIQUID CONTAINING MOSTLY WATER BUT ALSO RESIDUAL AMOUNTS OF
SULFUR COMPOUNDS AND TURPENTINE. THIS LIQUID IS KNOWN AS "FOUL CONDENSATE." THE FOUL CONDENSATE IS SENT FROM THE STRIPPING COLUMN TO AN APPROXIMATELY 100,000
GALLON-CAPACITY ATMOSPHERIC STORAGE TANK, USED TO STORE THE LIQUID AT,
OR CLOSE TO, AMBIENT PRESSURE. THE FOUL CONDENSATE TANK IS PRIMARILY USED TO REGULATE THE FLOW OF LIQUID BETWEEN THE TURPENTINE-STRIPPING COLUMN UPSTREAM AND A DOWNSTREAM UNIT THAT REMOVES THE REMAINING SULFUR COMPONENTS FROM THE WATER. DURING THE FEBRUARY 8 INCIDENT, THE MILL WAS UNDERGOING ITS ANNUAL SHUTDOWN. THE SHUTDOWN REQUIRED MILL EMPLOYEES
AND CONTRACT WORKERS TO PERFORM MAINTENANCE, INSPECTION, AND
UPGRADE TASKS THROUGHOUT THE FACILITY. ONE OF THESE TASKS WAS THE
REPAIR OF WATER PIPING LOCATED ABOVE AND CONNECTED TO THE FOUL CONDENSATE TANK THAT HAD SHIFTED AND CRACKED MONTHS EARLIER. THE REPAIR REQUIRED WELDING ON THE PIPING, COMMONLY REFERRED TO AS "HOT WORK." IN PREPARATION FOR THE HOT WORK, VALVES WERE CLOSED LEADING INTO
AND OUT OF THE FOUL CONDENSATE TANK, WHILE 10 FEET OF LIQUID REMAINED INSIDE. THE LIQUID WAS LEFT WITHIN THE TANK PARTIALLY BECAUSE THERE WERE NO PLANS TO WORK DIRECTLY ON THE TANK DURING THE OUTAGE. THE COMPANY ALSO ASSUMED
THAT THE TANK CONTAINED MOSTLY WATER, WAS SEALED OFF FROM THE ATMOSPHERE,
AND DID NOT POSE A SAFETY RISK. THESE ASSUMPTIONS WERE, HOWEVER, INCORRECT. RESIDUAL TURPENTINE,
NORMALLY PRESENT IN FOUL CONDENSATE, COLLECTED ON TOP OF THE LIQUID IN THE TANK
DUE TO ITS DENSITY. THE FOUL CONDENSATE TANK WAS DESIGNED SO THAT BY CHANGING THE HEIGHT OF THE LIQUID LEVEL INSIDE THE TANK THE RESIDUAL TURPENTINE WOULD BE SKIMMED OFF AND SENT TO A TURPENTINE RECOVERY SYSTEM. BUT IN THE MONTHS LEADING UP TO THE INCIDENT THE TURPENTINE WAS NOT REMOVED BECAUSE THERE WAS CONFUSION
AS TO WHO AT THE MILL WAS RESPONSIBLE FOR OPERATION
OF THE FOUL CONDENSATE TANK. DUE TO THIS CONFUSION, A VALVE DESIGNED TO DIRECT SKIMMED TURPENTINE TO THE MILL'S TURPENTINE RECOVERY
SYSTEM REMAINED CLOSED FOR MONTHS. AS A RESULT, LEADING UP TO THE
INCIDENT MORE FLAMMABLE TURPENTINE WAS PRESENT IN THE FOUL CONDENSATE TANK
THAN ANYONE EXPECTED. IN ADDITION, THERE ARE NORMALLY VAPORS INSIDE THE FOUL CONDENSATE TANK
IN THE SPACE ABOVE THE LIQUID. ALTHOUGH THOSE VAPORS CAN BECOME FLAMMABLE, THEY ARE SUPPOSED TO BE KEPT AT A CONCENTRATION THAT IT IS TOO RICH TO BURN. BUT DUE TO THE NON-ROUTINE CONDITIONS
EXPERIENCED DURING THE ANNUAL SHUTDOWN, THE CONTENTS OF THE TANK LIKELY COOLED, CREATING LOW-PRESSURE WITHIN THE TANK. THIS MOST LIKELY TRIGGERED A RELIEF VALVE
ON THE TANK'S ROOF TO ADD MORE AIR TO AVOID DAMAGING THE TANK FROM THE VACUUM CREATED BY LOW PRESSURE. THE VACUUM RELIEF VALVE WAS
LIKELY ONE OF A FEW POTENTIAL SOURCES THAT ALLOWED ENOUGH AIR INTO THE TANK TO CREATE AN EXPLOSIVE ATMOSPHERE. IN PREPARATION FOR THE HOT WORK, THE WATER PIPING WAS ISOLATED
FROM THE FOUL CONDENSATE TANK AND THE REST OF THE PROCESS BY CLOSED VALVES, AND THE PIPING WAS SEPARATED PHYSICALLY FROM THE TANK. AROUND 8:00 AM ON FEBRUARY 8, A MILL EMPLOYEE USED A GAS DETECTOR TO CHECK FOR A FLAMMABLE ATMOSPHERE IN AND AROUND THE WATER PIPING AND FOUND NONE. AS A RESULT, THE COMPANY ISSUED A
HOT WORK PERMIT FOR THE WELDING WORK. BUT EVEN THOUGH A FLAMMABLE ATMOSPHERE
WAS NOT PRESENT OUTSIDE THE TANK, THERE WAS A FLAMMABLE ATMOSPHERE INSIDE THE TANK. WITHOUT KNOWING THAT THE TANK POSED A SERIOUS HAZARD, THREE CONTRACT WORKERS BEGAN WELDING
ON THE WATER PIPING LOCATED ABOVE IT. THE CSB WAS UNABLE TO DETERMINE
AN EXACT IGNITION SOURCE BUT IT IS LIKELY THAT SPARKS OR MOLTEN SLAG
PRODUCED FROM THE HOT WORK LANDED ON OR NEAR THE FOUL CONDENSATE TANK, HEATING UP THE TANK WALL OR
OTHERWISE IGNITING THE CONTENTS INSIDE. OR IT IS POSSIBLE THAT THE HOT WORK WAS COMPLETE BUT AS THE TOOLS WERE LOWERED, A WELDING TORCH FELL AND CREATED AN
ELECTRIC ARC ON THE TANK OR ITS VENT PIPING. REGARDLESS, THE CSB DETERMINED
THAT HOT WORK ACTIVITIES LIKELY IGNITED THE FLAMMABLE VAPORS
AND LIQUID TURPENTINE INSIDE THE FOUL CONDENSATE TANK. AT 11:05 A.M. THERE WAS A LARGE EXPLOSION. THE TANK SEPARATED FROM ITS BASE AND LAUNCHED UP AND OVER A SIX-STORY STRUCTURE, LANDING APPROXIMATELY 375-FEET AWAY. THREE PEOPLE WERE KILLED
AND SEVEN WERE INJURED. ALL WERE CONTRACT EMPLOYEES WORKING NEAR THE FOUL CONDENSATE TANK.
That was a superior animation and very thorough. Very unfortunate.
My friends work there, and it was definitely a bad tragedy. The 2 workers were safety tied off to the tank, and it is believed that the work was almost complete and they were handing tools down
good summary of the event, however, I wish they had more discussion on the management issues on the loss of control of turpentine levels and ignition sources.
My brother was working on the other side of the plant when this happened. He was fine, but it took a while to hear anything about who had been injured (which is understandable). Around the time this happened there were quite a few other industry accidents. Plants that had never had any accidents were reporting limbs being mangled, complete amputations, and explosions. And the plants that didn’t have accidents were running safety drills day and night.
wow, what a simulation. that was some final destination status. feel bad for those families of this accident.
How many times do they need to say Fowl Condensate!