What is the purpose of clarifiers?
A clarifier is generally used to remove solid particulates or suspended solids from liquid for clarification and (or) thickening. Concentrated impurities, discharged from the bottom of the tank are known as sludge, while the particles that float to the surface of the liquid are called scum.
What is the general purpose of wastewater treatment?
The basic function of wastewater treatment is to speed up the natural processes by which water is purified. There are two basic stages in the treat- ment of wastes, primary and secondary, which are outlined here. In the primary stage, solids are allowed to settle and removed from wastewater.
What are the objectives of wastewater disposal?
The objective of municipal and industrial waste water treatment is to extract pollutants, remove toxicants, neutralise coarse particles, kill pathogens so that quality of discharged water is improved to reach the permissible level of water to be discharged into water bodies or for agricultural land.
What is the purpose of waste activated sludge?
The activated sludge process is a multi-chamber reactor unit that uses highly concentrated microorganisms to degrade organics and remove nutrients from wastewater, producing quality effluent. The goal is to maintain aerobic conditions and to keep the activated sludge suspended.
What are the objectives of primary sewage?
The main objectives of primary treatment of wastewater are: To reduce the strength of sewage to the extent 30% to 50%. To remove settleable solids by 80% to 90%. To reduce BOD by 30% to 35%.
What is waste activated sludge in wastewater treatment?
The excess quantity (mg/L) of microorganisms that must be removed from the process to keep the biological system in balance.
What is the main purpose of an equalization tank in an activated sludge system?
Industrial wastewater plants in general have an equalization tank with capacity to homogenize the composition and flowrate of the effluent generated in the industrial process. This equalization tank is designed so to accept certain composition variations in the outlet stream (or feed stream to the aeration tank).
How do wastewater clarifiers work?
The clarifier works by permitting the heavier and larger particles to settle to the bottom of the clarifier. The particles then form a bottom layer of sludge requiring regular removal and disposal. Clarified water then proceeds through several more steps before being sent for storage and use.