MBR (Membrane Bio-Reactor)
MBBR (Moving Bed Biofilm Reactor)
|Technology that combines 2 processes in one tank:|
– Activated sludge technology
– Separating microbial biomass using membrane
|– Technology using substrates for microorganisms to adhere, grow and develop in traditional Aerotank tanks|
Advantages of MBR and MBBR
|– Save space, premises, and construction costs|
– Treated wastewater has low BOD and COD
– Easy to increase capacity when expanding scale by increasing sludge concentration and filter area
– No need for sedimentation, filtration, or disinfection tanks
|– Saves more space than traditional Aerotanks|
– Microbial density per unit volume is higher than the traditional activated sludge treatment system
– Distribute microorganisms more evenly in the treatment tank
– Increase the contact area between microorganisms and wastewater
– Treated wastewater has low BOD and COD quality
– Easy to apply to existing treatment tanks
|Disadvantages||– The membrane is often clogged|
– Must use chemicals to clean the membrane (about 6 – 12 months, depending on the nature of the wastewater)
|– Needs sedimentation and filtration works behind MBBR|
– Depending on the quality of the substrate (MBBR), the adhesion ability of microorganisms is different
– The substrate is fragile after a period of use
MBR and MBBR Always need some additional and maintenance microorganisms
|Principle of phosphorus treatment using biological methods||Dephosphorylation in biological systems has the following mechanisms:|
– Many bacteria have the ability to store excess amounts of phosphorus as polyphosphorus in their cells (these organisms are collectively called PAOs).
– Under anaerobic conditions, PAOs will convert fermentation products (such as volatile fatty acids) into stored products inside the cell, and at the same time release phosphorus from stored polyphosphates.
– Under aerobic conditions, energy is generated from the oxidation of stored products and then polyphosphate accumulation in the cell increases.
– Phosphorus is removed from the process from residual sludge disposal
|Phosphorus treatment||The efficiency of the phosphorus treatment system, depending on the input phosphorus concentration, will gradually decrease in the first 2 years. After that, if the input wastewater has high P content, it is necessary to clean the membrane or replace the membrane and continuously withdraw sludge.||The P treatment system is effective, depending on the input phosphorus concentration, the efficiency will gradually decrease in the first 2 years. After that, if the effluent has high P content, it is necessary to continuously withdraw sludge.|
|WAS Sludge Disposal||– MBR simple operation, few problems|
– WAS mud volume is less than MBBR
|– MBBR often has many problems, operates similarly to Aerotank|
– WAS volume is less than Aerotank. Sludge draining is similar to Aerotank
|Issues of concern||– How to drain sludge?|
– What is the volume of sludge withdrawn?
– When to drain the sludge?
|– Quality of substrate?|
– Type of substrate?
|Lifespan||Normally 2 years. (depending on manufacturer)||Normally 2 years. (depending on manufacturer)|