blue
building
chemical
chimney
cloud
company
distill
distillery
energy
environment
environmental
equipment
factory
fuel
gas
gasoline
global
green
greenhouse
industrial
industry
manufacture
metal
oil
petrol
petroleum
pipe
plant
pollute
pollution
power
pressure
process
production
refine
refinery
sky
smoke
smokestack
stack
steam
steel
technology
tower
tree
tube
warming
working