Recycling water is the process where wastewater is converted into water that can be reused for other purposes like irrigation for gardens and agricultural fields or replenishment of groundwater or surface water. In some instances, recycled water that comes from your bathroom fulfills certain needs in residences, businesses and industries or treated to reach the standards of drinking water.
When recycling wastewater into drinking water, sewage goes through advanced primary treatment where water is separated from large particles. It then enters the sedimentation tanks where chemicals are added to the mix to make primary sludge settle to the bottom and scum to rise to the top. Once water is separated out and 80% of solids removed, the remaining liquid is clean enough to be released to the ocean or subject to secondary treatment. In the secondary treatment, bacteria are added to remaining liquid/wastewater to ingest organic solids and produce secondary sludge that settles to the bottom. Tertiary treatment filters water to remove whatever solids remain, disinfects it with chlorine and removes the salt. For Indirect Potable Reuse, wherein recycled water becomes drinking water, tertiary-treated water undergoes advanced water technology, and then spends time in groundwater or surface water like a reservoir before being sent to drinking water supplies.