Just about every industry produces wastewater as a byproduct and this water is treated before being reintroduced to the water supply. Some factories and processes will have wastewater that meets the regulations and can be sent to the local municipality reclamation center through in-house filtration and reclamation equipment while others will need to transport it to a specialized facility first.
The first steps in industrial wastewater treatment are screening, the first is bar screening to remove large items which will damage the plant and the second is to remove grit by flowing the influent over or through a grit chamber. Even when the wastewater is brought in by tanker truck, these steps are conducted to ensure plant safety and function.
Clarifying and Aeration
Primary clarification, or the initial separation of the solids and the wastewater, is next. These solids sink to the bottom and are pumped to a sludge processing area. Then comes the aeration step, where air is pumped into the tank for bacteria to grow and breakdown organic material. This is then sent to a second clarification for any remaining sediments.
The water will need to be disinfected once it has been clarified. The least expensive and most widely used method is adding chlorine to the water, but UV light and ozone are also effective. The chlorine level is then tested before being released into the environment.
Testing and Disposal
By this point in the process, the wastewater has been analyzed and tested several times, but a final test for the pH level, ammonia and nitrates as well as other substances is conducted before the water is introduced to the environment. This is to ensure the safety of the environment as well as an adherence to regulations and permits.
The treatment of industrial wastewater is a complex process that relies as much as possible on the natural ways that sediments are decomposed. There are tests throughout the process and a final check for environmental concerns before the treated water is reintroduced to the water system.