英文關鍵字
chemical
concrete
conservation
dirty
discharge
discharging
ecology
effluent
engineering
environment
environmental
flow
garbage
green
industrial
industry
liquid
pipe
plant
pollution
pump
recycling
removal
sedimentation
sewage
site
slimy
sludge
smell
smelly
stink
system
treatment
turbid
turbidity
waste
wastewater
water