Wastewater treatment by MBR technology (Activated sludge combine MBR)

MBR technology: Aerobic technology combined with MBR filter is one of the most advanced technology options. The tanks in the MBR technology also include treatment tanks such as air conditioners, anoxic, aerobic and silt. However, aerobic tanks, settling tanks and sterilization tanks are replaced by MBR membrane tanks.

MBR is a technology that combines two basic processes in a single unit:

(1) Biodegradation of organic matter

(2) Microbiology of micro-flitration bacteria.

In the tank maintaining the suspended sludge system, the reaction takes place in the tank like other normal biological processes, the treated water is separated by sludge by membrane filter with the membrane size fluctuating about 0.1. -0.4 microns. “Manem and Sanderson, 1996”.

Figure 1. Wastewater treatment scheme using MBR technology.

Advantages:

  • Ensuring the ability to treat waste water after the system reaches A standard QCVN 14: 2008 / BTNMT – National technical regulation on domestic wastewater.
  • Waste water after treatment is of very high quality, usually applied to systems with water quality requirements equivalent to column A QCVN 14: 2008 National technical regulation on domestic wastewater.
  • Withstands shock conditions for both waste stream flow and concentration of contaminants due to the operation of the building at high sludge concentrations.
  • The quality of output almost eliminates bacteria, pathogens and nuts that are relatively small in size.
  • Minimum space required compared to other alternatives, because the facility is designed to operate at high sludge concentrations, so that the volume of the building is small.
  • Minimize construction costs compared to other options because the construction work volume when using the MBR plan is the smallest.
  • The retention time of the tank is short because the sludge concentration is maintained at a high level, increasing the biological efficiency from 10-30%, without the need for secondary settling tanks and disinfection tanks, the volume of construction construction is reduced. .

Wastewater treatment processing lines under the chosen plan include the following stages of treatment: MBR technology

Figure 2. Technology diagram of wastewater treatment system using MBR technology.

Description of work items:

  • Wastewater receiving pit: Domestic wastewater generated from the tourist area’s items is collected by a self-flowing pipeline and then pumped to the sewage receiving pit. At the location of the treatment station, it is also the ending point of the drainage line. Waste water will be transferred to the fat separator.
  • Grease separation tank is responsible for removing grease, hydrocarbons before flowing to the conditioning tank itself.
  • Coarse screen: Waste water after being collected by the drainage network will be mechanically treated by a system of fine trash box placed in the conditioning tank. Refined trash box separates the garbage mixed with sewage, to protect the pump. Refined trash box is designed with SUS 304 stainless steel, equipped with lifting and sliding rails system, which helps the periodic waste collection process be convenient, saving investment costs compared to the plan to use the machine. motorized separation. However, fine trash screens are responsible for separating less than 5 mm sized waste from wastewater before flowing into biological tanks to protect the operation of MBR membrane modules.
  • Equalization tank: Receiving sewage, regulating the flow of wastewater. At the regulating tank, there is a pump system to regulate the flow operating according to the signal of the float indicator.
  • Sludge thickening tank: Store and treat the generated sludge in treatment facilities.
  • Anaerobic biological tanks: Integrated treatment of pollutants containing nitrogen and phosphorus. Here, the process reduces NO3to N2 gas takes place in anaerobic environment, NO3 plays the role of accepting Electron. Bacteria collect energy for growth from converting NO3 to N2.
  • Aerobic tank combined with MBR membrane filter: Removes suspended sediments, separates sludge, makes water, synthesizes organic substances. The MBR membrane filter is also responsible for thoroughly treating organic matters, ammonium nitrification, removing a part of pathogens in wastewater. Fine foam gas distribution system is installed under treatment tank to increase the efficiency of dispersing oxygen into water. This amount of oxygen is responsible for direct oxidation of organic matter, the remaining part of oxygen is responsible for mixing activated sludge with wastewater. The MBR filter module is responsible for separating sludge, and bacteria in the wastewater, maintaining the mud concentration in the building, ensuring the quality of water after treatment.