Biological Treatment


  • MBBR
  • IFAS
  • AvN
  • inDENSE
  • MABR
  • BKT
  • Lagoon Systems
World Water Works

MBBR: World Water WorksMoving Bed Biofilm Reactor (MBBR) technology

Moving Bed Biofilm Reactor technology

Moving Bed Biofilm Reactor (MBBR) processes improve reliability, simplify operation, and require less space than traditional wastewater treatment systems.

MBBR technology employs thousands of polyethylene biofilm carriers operating in mixed motion within an aerated wastewater treatment basin. Each individual biocarrier increases productivity through providing protected surface area to support the growth of heterotrophic and autotrophic bacteria within its cells. It is this high-density population of bacteria that achieves high-rate biodegradation within the system, while also offering process reliability and ease of operation.

This technology provides cost-effective treatment with minimal maintenance since MBBR processes self-maintain an optimum level of productive biofilm. Additionally, the biofilm attached to the mobile biocarriers within the system automatically responds to load fluctuations.

Process BenefitsMedia

Compact Design
A fraction of the size of conventional systems

Capacity can be easily upgraded by simply increasing the fill fraction of biofilm carriers

Single Pass Process
No return activated sludge stream required

Load Responsive
Actively sloughed biofilm automatically responds to load fluctuations
Minimal Maintenance
No F/M ratios or MLSS levels to maintain

MBBR processes are an excellent solution for common wastewater applications including:

  • BOD Reduction
  • Nitrification
  • Total Nitrogen Removal


Moving Bed Biofilm Reactor systems deliver a flexible, cost-effective, and easy-to-operate means to address current wastewater requirements and the expandability to meet future loads or more stringent discharge requirements within a compact design.

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WWW - MBBR Brochure WWW - MBBR Brochure (1049 KB)

World Water Works

IFAS: World Water Works

Integrated Fixed-Film Activated Sludge

Integrated Fixed Film Activated Sludge (IFAS) process is a state-of-the-art biological process used in treatment of municipal and industrial wastewaters for BOD removal, nitrification and denitrification. The process is a hybrid of suspended growth and fixed-film (attached growth) process and may be viewed as a combination of Activated Sludge and MBBR process. It is simply an Activated Sludge process with submerged but floating plastic media in aeration tank.  The plastic media is usually made of HDPE, polyethylene or polypropylene with specific gravity less than 1.0. In addition to the suspended growth bacteria in the aeration tank, the large surface area of the plastics provide abundant surface for bacterial growth. This increases the overall biomass concentration in the aeration tank enabling it to treat higher loads at lower reactor volume. It is usually assumed that most of the BOD removal is done by the suspended growth bacteria while most of the nitrification is performed by the nitrifiers that grow on the plastic media. Medium or coarse bubble diffusers uniformly placed at the bottom of the reactor maintains a dissolved oxygen (DO) concentration of > 3 mg/L. To retain the media flowing out of the tank, screens are placed on the downstream walls. A clarifier or a DAF is placed downstream of the MBBR tank to separate the biomass and the solids from the wastewater.  The concentrated sludge from the clarifier/DAF is recycled to the aeration tank as in an Activated Sludge process. 

For denitrification, anoxic IFAS tanks are used. The anoxic tank is similar to aerobic MBBR tank described above except that no oxygen is supplied. The tank contains no diffusers and the media is kept in suspension in the reactor through submersible mixers. Other feature such as the screen is the same as aerobic reactor although the design may be slightly different.

There are hundreds of IFAS installations worldwide. IFAS is used in treating municipal wastewaters and the industrial wastewaters including effluents from food and beverage plants, steel mills, oil refineries, petrochemicals, chemical plants, paper mills and any industries requiring wastewater treatment for BOD removal, nitrification and denitrification. IFAS is widely used for upgrading existing Activated Sludge plants designed for BOD removal only to nitrification and nitrogen removal.

World Water Works


A new process control system offered by World Water Works that controls the important balance between Ammonia Oxidizing Bacteria (AOB) and Nitrite Oxidizing Bacteria (NOB). AvN utilizes a patented process that applies selective pressure to aid in the segregation of the desired bacterial populations. This allows wastewater treatment systems to achieve more efficient removal of Total Nitrogen in the mainstream process at the lowest total energy cost possible.This unique technology can achieve very high removal rates of TN with very little carbon.

World Water Works


inDENSE™ technology solves the problem of floating or bulking sludge which can affect the treatment capacity and performance of many of wastewater treatment facilities. The inDENSE™ technology uses hydrocyclones to generate separate sludge streams based on their density. The lighter fraction, made up of poorer settling sludge is wasted from the plant, while the denser, better settling sludge is retained in the system. This selective wasting practice can greatly improve the wastewater treatment facility's sludge settling volume index (SVI).Furthermore, by preferentially selecting for the more dense bacteria, organisms such as GAO and PAO's are naturally selected for. This provides the opportunity to achieve BIO-P in the existing system for chemical free phosphorus removal.


Membrane Aerated Biofilm Reactor

Ideal for samll wastewater treatment plants, the Emefcy MABR is a spirally-wound sleeve with an internal air-side spacer, through which low pressure air is blown, and an external water side spacer between wraps of the spiral. The spiral is submerged in a tank to which wastewater is fed continuously and effluent is discharged by overflow. This solution saves energy by eliminating the need to blow compressed air into the depth of the water for aeration, through the implementation of Emefcy's patented passive aeration process. This leads to 90% less aeration energy than conventional system. Furthermore, the biofilm created on the surface of the membrane allows for simultaneous nitrification and de-nitrification.


Coming Soon

World Water Works


The BIOCOS® (Biological Combined System) process represents a cyclic activated sludge system that has been developed at the University of Innsbruck (Prof. Ingerle) throughout the last 15 years. The BIOCOS® main focus is to improve the conventional activated sludge process and the Sequestered Batch Reactor process in a continuousprocess that has two alternating sludge recycling and settling tanks without the need for any electro-mechanical equipment.

EDI's IDEAL™ Lagoon System

The Intermittently Decanted Extended Aeration Lagoon, or IDEAL, consists of an EDI floating lateral aeration system with Magnum fine bubble diffusers, two chains of BioReef BioCurtain, a static decanter with flow control valves, an overflow pipe with Storm Mode™, process controls, and a blower package. The simple operation of the IDEAL provides easy, cost-effective operation while the sophistication of the design provides high levels of BOD, TSS and ammonia removal.