SETTLING BASIN Russian patent published in 1997 - IPC

FIELD: settling of sewage waters. SUBSTANCE: the offered settling basin consists of vessel for collection and settling of sewage waters, fill dam, internal circular dams and closing dikes serving as filter elements and made of active material. Active material is used in form of limestone. Limestone is used for making internal slope of dam, internal filter elements and active layer of bed of collecting pond. Acid and deoxidizing sewage enter the internal central sector that leads to activation of physicothermal processes, then, sewage enters the other circular sector and is gradually neutralized, and fills the vessel of the main dam where processes of further neutralization take place due to presence of active material on internal slope of dam and bed of collecting pond. As a result of reaction of neutralization, insoluble precipitate is formed in form of gypsum on the bed of collecting pond that practically nullifies the bottom filtration characteristic to similar hydraulic structures. Gypsum as valuable product may be utilized upon completion of the service of sewage treatment structures. EFFECT: higher efficiency. 2 dwg