Sewage is primarily composed of water (about 99%) and a mixture of various organic and inorganic materials. The remaining 1% includes the following:
- Sewage, also known as wastewater, is primarily composed of water (about 99%) and a mixture of various organic and inorganic materials. The remaining 1% includes the following:
- Organic Matter:
- Human Waste: Feces and urine, which contain organic compounds, bacteria, and nutrients like nitrogen and phosphorus.
- Food Waste: Remnants from cooking, cleaning, and washing.
- Grease and Oils: From kitchens, restaurants, and industrial sources.
- Inorganic Matter:
- Dissolved Minerals: Salts, metals, and other chemical compounds.
- Sand and Grit: From runoff and washing.
- Microorganisms:
- Bacteria, viruses, and other pathogens.
- Beneficial microorganisms that help in breaking down organic matter.
- Nutrients:
- Nitrogen and phosphorus, which can contribute to environmental issues like eutrophication if not removed during treatment.
- Chemical Pollutants:
- Household chemicals from cleaning agents, detergents, and personal care products.
- Industrial chemicals and pharmaceuticals.
- Suspended Solids:
- Particulate matter such as silt, organic debris, and other undissolved substances.
- Other Contaminants:
- Microplastics, synthetic fibers, and other pollutants from urban and industrial runoff.
- Sewage composition varies depending on the source (domestic, industrial, or stormwater) and local activities contributing to the wastewater system.
Sewage composition varies depending on the source (domestic, industrial, or stormwater) and local activities contributing to the wastewater system.
Biological processes have been used to treat sewage for more than 100 years. In spite of our best endeavours, modern man has not been able to mechanically mimic the efficiencies of bacteria. By keeping the bacteria happy, we can optimise the treatment process – and this is the best we can do.
All our engineering endeavours strive to make the bacterial environment as friendly as possible.
Tools that we have at our disposal include;
- Sufficient retention time
- Efficient aeration and mixing
- pH control – if needed
- Temperature control
- Minimal ingress of bactericide
