機器
bacterium
basin
chemical
clean
cleaning
dirty
drain
ecology
effluent
environment
equipment
facility
factory
filter
filtration
flotation
flow
greywater
heat
industrial
industry
inside
metal
modern
pipe
pipeline
plant
pollution
pool
processing
pump
purification
purified
purity
recycle
recycling
reduce
removal
sanitary
sanitation
separation
sewage
sewer
sludge
smell
steel
tank
technology
treatment
tube
turbidity
valve
vat
waste
wastewater
water