Anaerobic Effluent Treatment is a wastewater treatment process that uses anaerobic bacteria (which do not need oxygen) to decompose the organic pollutants present in the effluent. This process can be used to treat effluents from the food, pulp and paper industries, among others, and can be followed by an aerobic treatment to remove the remaining pollutants and improve the quality of the water before being released into the environment.
Operating Process
There are two main anaerobic wastewater treatment processes:
- Anaerobic digestion: This process involves adding anaerobic bacteria to the effluent to break down organic pollutants. During this process, bacteria convert organic pollutants into carbon dioxide (CO2), methane (CH4) and other compounds. Methane can be collected and used as an energy source.
- Stationary anaerobic digestion: This process is similar to anaerobic digestion, but uses stationary tanks to keep anaerobic bacteria and organic pollutants together for a period of time. This allows the bacteria enough time to completely break down the organic pollutants.
It is important to remember that, in some cases, the anaerobic treatment may be insufficient to completely remove the organic pollutants from the effluent and, therefore, may be followed by an additional aerobic treatment to improve the water quality.
Benefits
There are several benefits of anaerobic wastewater treatment, including:
- Reduction of organic pollutants: Anaerobic treatment is effective in the decomposition of organic pollutants present in the effluent, reducing the pollutant load before being released into the environment.
- Biogas production: During the treatment process, anaerobic bacteria convert organic pollutants into methane, which is a powerful and versatile biogas. This biogas can be used as a source of energy to generate electricity, heat, among others.
- Low cost of operation: Anaerobic treatment is generally more economical than aerobic processes due to lower oxygen requirements and higher decomposition efficiency.
- Space footprint: Anaerobic treatment requires less space than aerobic processes, making it an attractive option for industries and other facilities with limited space.
- Odor Reduction: Anaerobic treatment can be used to reduce unpleasant odors that can be produced during the treatment of organic effluents.
Applications
Anaerobic wastewater treatment is widely used in various industries, including:
- Food industry: Anaerobic treatment is used to treat effluents generated by meat, dairy, fruit and vegetable industries, among others, where there are high concentrations of organic matter.
- Pulp and paper industry: Anaerobic treatment is used to treat effluents generated by pulp and paper manufacturing processes, where there are high concentrations of organic matter.
- Chemical industry: Anaerobic treatment is used to treat effluents generated by chemical industries, such as sulfuric acid production, where there are high concentrations of organic matter.
- Sewage Treatment: Anaerobic treatment is also used as part of domestic and commercial sewage treatment systems to break down organic pollutants present in sewage.
- Waste treatment: Anaerobic treatment is also used as part of waste treatment systems to break down the organic residues present in the waste.
In general, anaerobic treatment is a more suitable option when organic matter is high and other forms of treatment are not efficient.
