Hayes Lemmerz Aluminum Dust Explosion

Group 7

Jennifer Costello

Jenna Jeffryes

Wendy Salabay

Chelsea Winkelmann

Hayes Lemmerz Aluminum Dust Explosion

Background

Dust Explosions in the US

At least 281 dust fires and explosions since 1980

Hayes Lemmerz International, Inc.

Produces steel and aluminum wheels

20 facilities in 12 countries

The Incident

October 29th, 2003

Huntington, Indiana

Aluminum dust explosion

Killed 1, Injured 6

Case Study

Process Description

Incident Timeline

Results

Root Causes

Lessons Learned

The process of machining creates scrap metal, because it is a form of subtractive manufacturing. The wheel casts need to have metal removed before they are the ideal shape, so scrap metal pieces are formed. These scraps will go through chip processing for reuse.

5

Process Flow Diagram- Scrap Metal System

The first step of chip processing is dewatering. When a part is machined, cutting oil (typically an oil-water emulsion) is used to help stabilize the temperature and prolong the life of the cutting tip by keeping it lubricated. In the dewatering process, the scraps are spun in a centrifuge to remove this oil-water emulsion. They are then transferred to wet chip hoppers. From the hoppers, the scraps are transferred to the kilns for the drying and removal of the oil remaining on the surface of the scraps.

In these kilns, or dryers, the scraps are tumble-dried. This causes chips to break into smaller pieces. This creates dust. The process is designed with a minimum air flow through this part of the process to minimize dust issues and to minimize the oxidation of the metal scraps. Once the scraps (and dust) are dry, they are transferred to the dry chip hoppers with pressurized air.

Once they are through the hoppers, the scraps (and dust) are transferred again with pressurized air to the chip feed cyclone, also known as the vortex box, where the scraps drop down into the melt furnace for reuse. At this point the dust collector begins to work. It operates with a slight negative pressure and effectively pulls the air and dust up, while the heavier scraps drop down in the vortex box. There is a safety measure installed here called a spark box. Using baffles, it prevents embers and hot scraps from making it up towards the dust collector and providing a potential ignition source.

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Process Flow- Dust Collection System

The dust collector pulls the dust/air mixture through a duct run that has pulse jets along each side. These pulse jets work on a 90 second cycle and dislodge any settling dust from the duct work. The dust/air mixture then flows through a bag house. The bag house has many filters that trap the dust particles and allow the air to proceed through, now clean of particulate, and out into the atmosphere.

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Chip Feed System was shut down due to smoldering fire however workers did not turn off dust collector fan.

Fire was determined out, fume duct was opened and residue was cleared out

Two hours later the dry chip feed was restarted

Within ten minutes maintenance noticed chips were falling out of the spark box into the dust collector duct

A fireball erupted from beneath the furnace fume hood

Timeline

http://www.youtube.com/watch?feature=player_detailpage&v=3d37Ca3E4fA#t=167s

5:01

9

Aftermath

Workers clothing was engulfed in flames along with two other nearby workers

Fire reached the roof where a contract worker was knocked off his feet but able to notify authorities

An emergency was reported over intercom, employees evacuated

Fire department on site within minutes

Fire was extinguished two hours later

Large amount of structural damage

Root Causes

Accumulation of dust

Improper housekeeping

Lack of knowledge of danger

Improper communication between management and operators

Failure to investigate near misses

Lessons Learned

Dust explosions are a major problem

Minimal amounts of energy are required to explode

Airborne dust can provide fuel for secondary explosions

Dust lying around can easily become airborne during an explosion

Learn from near misses and minor accidents

With proper documentation

Easier to connect the dots

Prevention

Good housekeeping

Inert the facility if possible

Make sure all employees are aware of danger and wear necessary PPE

Vent explosions/ use blast walls

Regulations and legislations

Currently no mandates

H.R. 522: Worker Protection Against Combustible Dust Explosions and Fires Act of 2011- still pending

2008 sugar dust explosions

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Summary

Incident & Results

Aluminum dust explosion resulting in 1 death

Fire started in furnace, led to a secondary explosion

Major cause: Dust build-up

Lessons learned: The importance of proper housekeeping and good communication

Questions?

Works Cited

1. Blair, Angela S. "Dust Explosion Incidents and Regulations in the United States." Journal of Loss Prevention in the Process Industries 20.4-6 (2007): 523-29. SciVerse. Web. 25 Feb. 2012. .

Crowl, Daniel A., and Joseph F. Louvar. "Concepts to Prevent Fires and Explosions." Chemical Process Safety: Fundamentals with Applications. Upper Saddle River, NJ: Prentice Hall, 2011. 317-74. Print.

Crowl, Daniel A., and Joseph F. Louvar. "Fires and Explosions." Chemical Process Safety: Fundamentals with Applications. Upper Saddle River, NJ: Prentice Hall, 2011. 245-304. Print.

"CSB Determines Fatal 2003 Incident at Hayes Lemmerz Plant in Indiana Most Likely Caused by Explosion in Dust Collection System; Company Did Not Identify or Control Hazards of Aluminum Dust." U.S. Chemical Safety and Hazard Investigation Board. Web. 25 Feb. 2012. .

3. CSB. "Investigation Report:Aluminum Dust Explosion." U.S. Chemical Safety and Hazard Investigation Board. Web. 21 Feb. 2012. .

2. "Cutting Edge Technology and Products from Hayes Lemmerz." Cutting Edge Technology and Products from Hayes Lemmerz. Web. 25 Feb. 2012. .

4. "Emulsion." Merriam-Webster. Merriam-Webster. Web. 21 Feb. 2012. .