blue
built
bunded
burner
business
carbon
chemical
chemistry
chimney
construction
diesel
dioxide
energy
engineer
environment
equipment
fire
flame
flaming
flare
fossil
fuel
fuel oil
gas
gasoline
industrial
metal
natural
nuts
oil
orange
outdoor
petrochemical
petroleum
pipeline
plant
pollutant
pollution
power
processing
production
refinery
sand
steam
supply
support
technology
tower
warming
yellow