Biomass/Bioenergy - Environmental Impacts of Renewable Energy - page 238

Fire and Explosion Hazards *
Employers producing biofuels may expose workers to potential fire and explosion
hazards, and they must protect them from these hazards by preventing releases,
avoiding ignition of spills, and having appropriate fire protection systems and emer-
gency response procedures in place. Engineering controls that should be used include
the following:

• Good facility layout

• Proper design of vessels and piping systems

• Proper selection of electrical equipment for use in hazardous (classified)

areas

• Adequate instrumentation with alarms, interlocks, and shutdowns

Administration controls that should be used include the following:

• Operating procedures

• Good maintenance practices

• Safe work practices/procedures

Facilities processing more than 10,000 pounds of flammable liquids or flammable
mixtures may be covered by 29 CFR 1910.119 (Process Safety Management of
Highly Hazardous Chemicals).

Chemical Reactivity Hazards †
Biofuels manufacturing processes can present reactive hazards. Although ethanol
production by fermentation involves biological reactions that do not present an
explosive “run-away reaction” hazard, some processes for making ethanol from
materials such as waste paper and wood chips use concentrated acids and bases
that can react vigorously with many materials. Also, the gases produced during
ethanol fermentation need to be properly vented to avoid overpressuring equip-
ment and piping. Biodiesel is produced by the chemical reaction of organic oils
with an alcohol, typically using a strong base as a catalyst. The glycerin that is co-
produced with the biodiesel is then often treated with acid. These reactions need
to be carefully controlled. Failure to control potentially dangerous chemical reac-
tions can lead to the rupture of equipment and piping, explosions, fires, and expo-
sures to hazardous chemicals. Employers need to protect their workers from these
hazards. Engineering and administrative controls to keep the process within safe
limits include controlling the rate and order of chemical addition, providing robust
cooling, segregating incompatible materials to prevent inadvertent mixing, and the
use of detailed operating procedures. Several OSHA standards address potential
reactive hazards:

* Adapted from OSHA's Green Job Hazards: Biofuels—Fire and Explosion Hazards of Biofuels , https://
www.osha.gov/dep/greenjobs/bio_ireexplosion.html.
† Adapted from OSHA's Green Job Hazards: Biofuels—Chemical Reactivity Hazards in Biofuel
Manufacturing , https://www.osha.gov/dep/greenjobs/bio_chemical.html.