機器
environmental
chemical
chemistry
chimney
collection
construction
diesel
dioxide
distillation
energy
engineering
environment
equipment
facility
factory
flat icon
fuel
gas
gasoline
heavy
icon
illustration
industrial
industry
metal
object
oil
petrochemical
petroleum
pipe
pipeline
piping
plant
pollution
power
production
pump
refinery
rhombus
set
sign
steel
structure
tank
technology
tower
tube