Removing suspended solids from wastewater is one of the basic steps of wastewater treatment, including insoluble solid particles, organic matter, microorganisms, etc. Here are some common ways to remove suspended solids from wastewater:
1.Primary Treatment:
Screens & Screens**: Used to remove large floating debris such as paper, plastic, cloth, etc. from wastewater.
Grit Remover **: Removal of sand particles, stones and other particles with large specific gravity through sedimentation.
2.Secondary Treatment:
Activated sludge method**: microorganisms are used to degrade organic matter, and the flocs formed by suspended solids and microorganisms are removed by sedimentation in the sedimentation tank.
Biofilm method**: such as biofilters, bioturntables, etc., microorganisms attach to the fixed support material to form a biofilm and degrade organic matter, and the suspended matter is removed as the biofilm falls off.
3.Processing:
Flocculation and sedimentation**: Flocculants (e.g. iron salts, aluminum salts, etc.) are added to the wastewater to form flocs in suspended solids, which are then removed by precipitation.
Air flotation**: By injecting tiny bubbles into the wastewater, the suspended solids adhere to the bubbles and float to the water surface, forming scum to be removed.
Filtration**: Sand filter, activated carbon filter, etc., are used to remove fine suspended solids through the interception of the medium.
4.Advanced Processing:
Membrane separation technology**: such as microfiltration, ultrafiltration, nanofiltration, etc., to achieve the separation of suspended solids through semi-permeable membranes.
Centrifugal separation**: Centrifugal force is used to separate suspended solids from water.
5.Chemical Treatment:
Chemical oxidation**: The use of chemical oxidants (e.g., ozone, hydrogen peroxide, etc.) to oxidize suspended solids and change their physicochemical properties for subsequent removal.
Chemical precipitation**: Chemical reagents are added to form a precipitate of suspended solids, which is then removed by sedimentation or filtration.
Each method has its own applicable conditions, advantages and disadvantages, and the most appropriate treatment technology needs to be selected according to the types, concentrations, water quality characteristics, economic costs, and environmental protection requirements of the suspended solids in the wastewater. At the same time, the relevant environmental protection regulations and standards should be strictly observed during the treatment process to ensure the treatment effect and protect the environment.