Class Tested by UM Material and Energy Balances Course in Fall 2018

• Rinsed out empty drum, but residual acetone was left behind
• Began welding, arc burned throughigniting acetone vapor causing an explosion

• Control of the hot and cold side of the heat exchanger
• Restart the reboiler after 16 months in standby without any previous revision
• Operator supervisor ignorance about the propene inside the heat exchanger
• Module for Material and Energy Balances, Thermo and Fluid Mechanics

Class Tested by UM Material and Energy Balances Course in Fall 2018

• One old level measurement system
• No additional systems in case of failure
• Usually cable breakages

• Video illustrating ways to prevent harm caused my mishandling sodium hydrosulfide
• Sodium Hydrosulfide(NaHs) is extremely dangerous if not handled properly

Class Tested by UM Thermodynamics Course in Spring 2018

• Propylene gas exposed to outdoor high temperatures
• Thermo gas pressure, pressure relief valve acetylene different from propylene too low setting from propylene

• Hydraulics Shock ruptured pipe and released anhydrous ammonia to yield a toxic vapor cloud
• Carry out calculations to model shock and prevent hydraulic shock.

• 1 Minute 43 second video showing dismantling of tanks with corrosion pitted 0.75inch and 0.4inch holes where the leak occurred. Release 11,000 gallons of a mixture of methylcychohexanemethanol (MCHM) and polyglycol ethers. The storage tanks were 20 ft. in diameter and 20 ft. tall
• b. 341 question: Estimate the rate of leakage from tank of crude NCHM and Polyglycol. Crude methlycyclohexane methanol and polyglycol ether leaked approximately 10,000 gallons over 12 days

• Blowout preventer failed.
• Good explanation of failures leading to the blowout
• Force a bent pipe. Not sure what type of calculation can be done here

• Acetylene generated by reaction of calcium carbide + H2O
• A check-valve failure allowing C2H2 to escape to the shed. Calculate amount of gas in plume. Also volume of plume versus explosive “power”
• Failure to check valve that allowed flow from acetylene reaction from into shed.

• Control of the hot and cold side of the heat exchanger
• Restart the reboiler after 16 months in standby without any previous revision
• Operator supervisor ignorance about the propene inside the heat exchanger
• Module for Material and Energy Balances, Thermo and Fluid Mechanics

• Using a forty-year-old heat exchanger
• Very old equipment
• Determining vulnerability of equipment to HTHA is inadequate

• Operator’s ignorance.

Class Tested by UM Heat and Mass Transfer Course in Fall 2018

• Control of the hot and cold side of the heat exchanger
• Restart the reboiler after 16 months in standby without any previous revision
• Operator supervisor ignorance about the propene inside the heat exchanger
• Module for Material and Energy Balances, Thermo and Fluid Mechanics

• Could calculate vapor composition and flammable limits
• Air got inside a tank during switching of the lines. The tank was electrically charged.

• Flammable vapor accumulation due to
• 1) Exhaust fans turned off
• 2) Steam valve left open that continued to heat mixture of heptane and proply alcohols for 8 hours. Vapor continued to escape and exploded

• The storage of chemicals such as pool chlorination tablets.

• 18,000 gallon propane tank exploded due to teenagers running into the line with an ATV
• Excess flow valves failed trying to stop the propane leak
• The explosion was due to boiling liquid vapor expanding inside the tank
• The firefighters were unaware of the hazard and never trained for an event like this

• To use propane as fuel inside a building

• Very high pressure, causing a geyser-like release from the vent stack

• Excess flow. Wrong design of the excess flow valve

• Fluid cracking unit (STTR) vapor and catalyst separated and coke on catalyst burned in regnerator. Coke particles found their way into electrostatic precipitator and explosion occurred
• One of the slide valves malfunctioned
• Hydrocarbon flammability unknown
• Bad decision taken by the team with regard to steam injection

• Bophal: Methyl Isocynate + H2O -> Bophal spawned change in regulations
• Similar to Example 13-2 Increase amount in reactor rather than making two batches. Heat generated becamse greater than heat removed

• Corroded piping
• The refinery used obsolete equipment rather than the safest modern designs
• Analysis of the effectiveness of safeguards intended to control hazards was missing

• Ammonium nitrate explosion radiant heat increased surface temperature of NH4NO3
• Poor Hazard awareness
• Proximity of the facility to nearby homes and businesses
• Inadequate emergency plan
• Limited regulatory oversight

• Isobutene released and a plume formed and exploded
• Operators ignorance
• Distance between the valve and the machine that ignited
• Plug-valve operated manually
• Pressurized isobutene escape

• Indoor purging of natural gas, CH4. Water heater. What is the "explosive power" of a gas plume of a given size. Should have used combustible detector
• The inclusion of a non-cleaning gas. The danger of natural gas into work areas

Class Tested by UM Chemical Reaction Engineering Course in Fall 2018

• Increase of temperature. The cooling system could fail

• Sterilize with ethylene oxide in chambers filled with medical instruments. Flow water into chambers to a eliminated gas. However, the operator skipped washer steps resulting in trace levels of ethylene oxide gas being passed over a flame heated catalyst to be removed oxidizers
• What is heat of reaction? What is amplitude of the pressure waves?

• 4 major accidents
• Vapor explosion example 13-2 increase amount semibatch -> slow addition easy to remove heat
• Point of no return
• BP Polymers. Waste Plastic into tank molten plastic sealed relief valve secondary reaction in molten plastic to produce gas. Molten polymer sprayed onto workers
• Marton International
• MFG Plant. Release of toxic vapors. Did semibatch -> batch -> explosion not scale up properly Alyl alochol U. Point of no return
• Distillation of MM Toluene. Runaway reaction in column. Anhydrous ammonia

• Video illustrating ways to prevent harm caused my mishandling sodium hydrosulfide
• Sodium Hydrosulfide(NaHs) is extremely dangerous if not handled properly

Class Tested by UM Process Control Course in Fall 2018

• Vehicle stack valve releasing falmmable liquid proplyene and vapor cloud
• How would one instrument control system

• High pressure. No relief system

• Manufactures organic peroxides
• Hurricane Harvey Flooding disabled the refrigeration

• Opened valve of wrong reactor releasing vinyl chloride that reached an ignition source and exploded

• Change in procedures to disassemble and dispose of fireworks. An explosion resulted from not analyzing change with regard to PPA
• No analysis of the hazards
• Friction of the chairs
• Hazard of the black powder

• Recommended inspections not performed
• Vessels corrosion
• High pressures and temperatures and vessels did not meet code

• Never really illustrated what happened. Suggests that an ignition source was provided by two high school students playing in a tank half filled with crude oil that exploded
• Flammable vapor
• Proximity of the location

• Pipe corrosion
• The component that failed had no record of ever being inspected for corrosion as it thinned over the years
• Bad inspection strategies

• Gasoline overflowed in storage tanks
• Malfunction of tank level measurement

• Malfunction of tank level measurements
• No additional systems in case of failure

• Gasoline overflow
• Liquid level measurement failed

• The refinery used obsolete equipment rather than the safest modern designs
• Analysis of the effectiveness of safeguards inteded to control hazards was missing

• Spilled fine sugar on floor. Dust collection system was not working properly. Spilled sugar on floor. Trapped sugar in belt system. Large surface area of fine granulated sugar
• Also power plant in Connecticut. CH4 gas flows in pipes confined space

• Iron dust carried on buckets ignited. High surface area of dust particles leading to rapid burning role. Malfunction of bucket elevator, which formed dust particles in air that found a spark and dust collectors were often down for maintenance. Calculated heat of reaction for iron dust of O2
• Also example of gas leak example. Assumed it was an N2 leak and it was really H2. Metal on metal spark ignite hydrogen, which then ignited iron dust. Did not test for flammable gas

• Combustible zirconium and titanium dust and spark needed dust collector no standard for dust
• Engineering controls for metal dust missing
• Titanium powder high flammability

• Hydrocarbon heated by sun and vaporize and flow through line. Find spark from welding

• Welding accident
• The lessons to avoid not work accidents
• Conduct Hazard Evaluation. THINK! KTPPA
• 3000 gallons of methanol
• Shows effects of accident on victim's family
• Delaware River
• <ul><li>Water sulfuric acid and hydrocarbons</li><li>Heating up hydrocarbons during day</li><li>Con Agra loads</li></ul>
• Did not repeat flammable gas testing
• What hazard assessment should be performed?

• Flammable liquids fed to isomerization unit
• Malfunctions cause the unit to over flow with flammable liquid
• What is the TNT equivalent of 1.5 meters diameter by 3 meters high plume and a 42 meter high tank explodes
• Need to translate Spanish

• Hot Work used acetylene touch on crude oil line
• Same as one of others
• Issued 7 lessons to prevent Hot work accident volume at gas vs. heating of vessels by sum to produce flammable gas

• Good description of process
• February 2010 Issued Bulletin Seven Key Lessoned to Prevent Deaths in Hot Works. Also the need in and around tanks to monitor for flammable gasses in tanks vinyl fluoride gas was present in flowed into tank 1. What was pressure drop to cause flow?
• Flammable gas contained in the tank
• No testing of the flammability of the gas inside the tank
• Deficiencies in the safety management hot work

• Massive fire erupted due to a water leak
• Leak caused crack in out-of-service piping releasing high-pressure liquid propane
• Lack of program to identify and freeze-protect out-of-service equipment
• Insufficient fireproofing of structural steel

• Tried to clear blockage in piping and had a failed start up, but caused high pressure in other piping
• Drained piping to deal with pressure, didn’t realize pipes actually unblocked
• Liquid methyl mercaptan was released
• Inadequate toxic gas detection system in building
• Rooftop ventilation fans were not working also

• Caused due to welding of a pipeline that still contained the solvent, coal tar naphtha
• It was believed the solvent was removed prior to work

• Truck suffered mechanical problems causing it to overturn
• A crash caused the explosion sent thick plumes of smoke into air

• Replaced Methomyl-Larvin unit pressure vessel that solvent could be used as fuel
• Needed to prevent any possible runaway reactions in vessel
• Restarted unit prematurely, making start up risky
• Operators bypassed safety lock causing temperature to climb in vessel
• Could not control the runaway reaction they created, causing an explosion of the vessel