What is sewage sludge?

Sewage sludge, also known as biosolids, is a byproduct of wastewater treatment processes. It is the solid residue that remains after the treatment of sewage or wastewater in treatment plants. Sewage sludge contains a mixture of organic and inorganic materials, including human waste, food scraps, chemicals, and other pollutants that are removed during the treatment process. It is typically a semi-solid or slurry-like substance with a high water content. Sewage sludge can be further treated and processed to remove harmful pathogens and reduce its volume before it is disposed of or used for beneficial purposes such as land application as fertilizer or soil conditioner.