AOP – ADVANCED OXIDATION PROCESS
Advanced oxidation process is defined as oxidation process based on the hydroxyl radical (·OH) which created in reactor in very short time. Hydroxyl radical is one of strongest oxidation agent, could oxidize all organic substances and transfer them into nontoxic inorganic substances (mineralization) such CO2, H2O or degradable substances such as short chain organic acids, inorganic acid …
This process is normally applied in treatment wastewater with high concentration of hardly degradable COD and colour. Oxidation process can be used in tertiary treatment step to remove remaining COD and colour; or used in first chemical treatment step (before the biological treatment step) to increase BOD/COD ratio.
Picture below is description of one Koastal Eco’s plant using Fenton process for advanced oxidation treatment with capacity 1,500 m3/day.
MFT – MULTILAYER FILTER TANK
This filtration system is a pressurized filter including many filtration material layers with many dimensions. Material arrangement allows to remove big suspended solids at the first material layer, the smaller suspended solids will be kept in deeper material layer leading to increasing suspended solids and turbidity removal efficiency.
This process is normally applied in projects with high treated effluent or with recycling for simple purpose such as irrigation, washing belt filter press …
Project scale Koastal Eco applied for pressured filter is up to 1,500 m3/day.
UF - ULTRAFILTRATION
UF are used for separation of suspended solids, colloids with membranes pore size between 20nm – 0.1µm and low operation pressure. This step can be seen as coarse RO membrane (if any). The popular application of this kind of membrane is MBR (please see further in Biological treatment process and Wastewater recycling process).
Recycling’s application: treated effluent can be reused for road cleaning, car washing, landscape irrigation, toilet flushing.
Water recycling in Vietnam nowadays is normally applied in a part of WWTP’s capacity due to investment cost limitation. UF system capacity Koastal Eco applied for recycling water is 25 m3/h.