blast furnace
chimney
clean
cold wind
economic
emission
energy
energy saving
enterprise
environmental protection
exhaust gas
factory
flame
fluid
fog
gas
green
heavy industry
hot air stove
industry
ironmaking
led
light
medium
night
night view
pipeline
pollution
primary industry
release
residual pressure
second time
smoke
smoke exhaust
steel
steel making
steel plant
trt
waste heat