英文關鍵字
aerated
aerotank
bacterium
basin
biology
biomass
blow
blue
bubble
chamber
chemical
clean
cleaning
closeup
dirt
dirty
ecology
environment
filter
filtration
foam
grit
industry
liquid
mud
oxygen
pipe
plant
pollution
pool
purification
reduce
reservoir
sedimentation
settle
settler
sewage
sewer
slimy
sludge
spume
stage
storage
surface
tank
technology
treatment
waste
water
waterworks