MICROPUR is an advanced mechanical preliminary treatment method. This innovative fine sieving process takes the pressure off downstream treatment processes by reliably removing coarse contaminants such as hair and fibers from the wastewater. In addition, it significantly reduces suspended solids and, in turn, other unwanted nutrients. When used upstream of a biological treatment process, it can achieve a degree of screening that is equivalent to that of primary sedimentation but without taking up anywhere near as much space. The MICROPUR process is the ideal addition to plants that already employ a membrane bioreactor (MICROPUR-MBR) or other biological treatment methods.

BIOPUR is a biofiltration system developed by WABAG for the biological treatment of wastewater. It uses biofilms – which are cultivated on solid surfaces – to biologically degrade the pollutants in the wastewater. At the same time, suspended solids are captured by the filter materials. BIOPUR is a modern and space-saving process that is capable of meeting the toughest of water treatment requirements in both municipal and industrial contexts.

The carrier materials and filter media are tailored precisely to water treatment needs and so the system is completely customizable for a multitude of applications. The system can be effectively combined with other treatment methods such as tertiary filtration, making it ideal for plants that are tasked with removing micropollutants.

FLUOPUR is the name of WABAG's moving bed process for the biological treatment of wastewater. It can be used as a moving bed (MBBR) on its own or in combination with activated sludge (hybrid or IFAS). The patented carrier material, which was developed by WABAG, is used to cultivate biofilms that are also capable of performing other tasks according to requirements.

The FLUOPUR process requires less space than conventional activated sludge treatment and virtually any tank geometry can be selected. That makes FLUOPUR ideal for extending existing activated sludge processes when they hit capacity bottlenecks or need to meet more stringent purity requirements.

Membrane bioreactors (MBR) are powerful systems for the biological treatment of wastewater. The biological treatment stage performs a similar role to a conventional activated sludge system. However, in this case, the activated sludge and clean wastewater are not separated in a secondary sedimentation tank by the force of gravity but are separated using membrane filtration. As a result, the filtrate contains no solid matter and virtually no bacteria and microorganisms. In addition, the concentration of the sludge in the activated sludge tanks is not limited by the performance of the secondary sedimentation system, allowing you to work with higher sludge concentrations. This results in complete solutions that are highly compact.

Membrane bioreactors are often the technology of choice for meeting stringent purity requirements. However, they can also be used very effectively to boost the performance of existing plants. Membrane bioreactors are suitable for municipal and industrial wastewater treatment applications, and are also a key technology for the reuse of water. A specific preliminary treatment method (particularly in the form of MICROPUR) can be incorporated and appropriate operation ensured to create a membrane filtration solution that is both straightforward and economical.

SBR is a system for the biological treatment of wastewater. In contrast to conventional activated sludge processes where the wastewater is treated by passing it through a series of tanks, the SBR method involves carrying out the different steps one after another in the same tank.

As the reactors are filled on a batch-by-batch basis, several SBR tanks and/or an influent buffer tank are required to treat wastewater continuously. On the other hand, there is no need for the recirculation equipment that goes hand in hand with continuous systems, and the cleaning performance can be flexibly and perfectly adapted to requirements. The typical steps involved in the process are:

• Fill (mixed or aerated)
• Reaction: aeration or mixing
• Sedimentation
• Decantation: extraction of the clean water

Nereda is a highly advanced technology for biological wastewater treatment that is based on the SBR method and harnesses the power of aerobic granular sludge. With this technology, the bacteria grow naturally in compact granules instead of in flocs.

These granules have excellent settling properties, the advantages of which are many: the biomass concentration in the reactor is very high, but the sedimentation phase is extremely short. What's more, the reactor can be filled while clear water is being extracted. This results in excellent biological performance and means that virtually all of the cycle time can be spent on biological processes, leading to small reactors with minimal space requirements. Another factor is that many biological processes take place within the compact granules simultaneously. This results in high rates of nitrogen and biological phosphorus removal, and largely eliminates the need for precipitating agents. 

Compared to conventional SBR technology, these systems are much more compact overall and produce a better quality of effluent.

Filtration is one of the key processes involved in the treatment of water. The technology was developed in the 1960s – when the company was still called Sulzer – but has undergone continuous enhancement ever since. The origins of wastewater filtration can be traced back to the 1970s. Today, a whole host of systems and filter media are available for various applications:

• Single- and multilayer filters (in various combinations)
• Filters with a nozzle floor or drainage system
• Various designs and modes of operation
• Various backwashing programs

Effective backwashing is crucial to ensuring reliable long-term operation. For this, there is a choice of sophisticated backwashing concepts. Together with the optimized filter construction technology, this leads to excellent results.

The BIOZONE process was originally developed by WABAG for treating wastewater containing a high percentage of organic compounds with low biodegradability. It generally consists of a two-stage biological treatment process with an intermediate oxidation step. The range of application encompasses:

• The pulp and paper industry
• The pharmaceutical industry
• The textile industry
• The chemical industry
• The food industry
• The landfill leachate industry

Another way to remove micropollutants is adsorption by powdered activated carbon (PAC). This involves adding the PAC to the secondary treatment effluent and removing it from the wastewater again after a specific contact time. Separation can be achieved in two stages (sedimentation and filtration) or in a single stage (i.e., filtration without additional sedimentation). In both cases, deep bed filtration technology delivers the best performance. The defining features of the single-stage process are that it saves a huge amount of space and cuts costs due to the omission of the sedimentation stage.

Membrane filtration processes can also be used to capture the PAC. Two appealing solutions are available:

• Simultaneous dosing of the PAC into the activated sludge on MBR systems (membrane bioreactors). This results in a highly compact plant that is still capable of achieving the generally exceptional effluent quality that you would expect from an MBR. Due to several factors, the rate of PAC consumption is no higher than with tertiary dosing (when the PAC is added to the secondary treatment effluent), making this concept even more attractive.
  
• With tertiary PAC dosing, the carbon is separated by means of membrane filtration instead of using deep bed filtration.
  

With this process, the micropollutants are removed through adsorption by granulated activated carbon (instead of PAC). Here, the GAC serves as the filter medium for deep bed filtration. As a result, there is no need for the PAC dosing, adsorption reaction, and PAC removal steps – essentially making this solution very straightforward. On the other hand, the carbon has to be periodically replaced or regenerated.

The separate treatment of the nitrogenous return supernatant from the sludge treatment process constitutes a special application. In this way, the treatment plant's denitrification performance can be boosted while taking the pressure off the biological treatment stage. The nitrogen can be removed from the return supernatant conventionally by using an external denitrification substrate or can be removed by means of the innovative anammox process.

The conventional method of removing the nitrogen separately generates high operating costs because of the need for intensive aeration and the addition of methanol. With the anammox method, the operating conditions are carefully controlled so that the ammonium is only oxidized into nitrite (instead of nitrate). This is then converted into nitrogen – at the same time as ammonium – by special microorganisms. As a result, this process requires 60% less oxygen and no methanol at all.