The Activated Sludge technology is one of the most worldwide spread since 1914 when it was developed. It is used for the treatment of both industrial and municipal effluents.
The process consists of an aereation tank with complete and continuous mixing provided by diffusers or mechanical aerators. The "sludge" (biomass) feed and grow from the organic matter of residual water. The sludge grows in the form of clots that settle when passing through a secondary clarifier. The clarified water overflows on the top of the tank, while the concentrated biomass is recirculated back to the aereation tank or it´s sent to the sludge treatment system.
Its configuration is like a conventional activated sludge process, but with an anaerobic and/or anoxic selector prior to aeration tank.
This system is used when it is necessary to remove not only organic matter but also residual water nutrients, such as nitrogen and/or phosphorus. The microorganisms are developed and adapted to achieve the biological removal of nutrients.
The nutrient removal of residual water is required when the treated water will be discharged into water bodies, this is to avoid eutrophication in rivers, lakes or the sea.
The Modified Luzdack Ettinger (MLE) is a widely used configuration to remove nitrogen. However, apart from this, IBTech® evaluates different types of configurations depending on the characterization of the water influent and the required quality of the effluent.
This process is designed for the elimination not only of organic pollutants, but also of ammoniacal nitrogen in a small space.
The system is formed by three modules: an UASB reactor, a denitrification upflow sludge bed reactor (anoxic), and a nitrification attached growth reactor (submerged filter). Also, there is a recirculation stream from the nitrification reactor to the denitrification one. At the denitrification reactor, the oxidized nitrogen is transformed into molecular nitrogen (N2) which is harmless to the environment, and is vented to the atmosphere, thus its removal from the water.
The Sequencing Batch Reactor is a system that operates in stages. In each stage, a different process is carried out that together removes organic matter, as well as other pollutants such as nitrogen and phosphorus. Furthermore, this reactor has the advantage that everything happens in the same tank, including sedimentation, which represents a considerable saving in space.
The operating stages of the SBR reactors are:
The reactor has control mechanisms that allow constant online monitoring and with historical record of events. This allows the user to make quick (preventive and corrective) decisions and have total control of the process.
BUENAVENTURAThe Submerged Aerated Filter consists of a packed tank with an inert and resistant material, which provides the area for the adherence of the microorganisms (fixed biomass) responsible for the degradation of the organic matter contained in the wastewater. The oxygen is incorporated into the water through air diffusers placed at the bottom of the tank.
The Trickling Filter or biofilter is a process widely used for the wastewater treatment. The biological filter is a process designed to put the wastewater in contact with the biomass adhered to a fixed support medium, which constitutes a bed of biological oxidation.
The objective of a trickling filter is to reduce the organic load existing in domestic or industrial sewage. It consists of a natural or synthetic bed above which the wastewater is applied and where the microorganisms grow as a biofilm or bed.
The organic matter present in the wastewater is absorbed and decomposed by the biomass attached to the filter medium. Each filter has a bottom drain system to collect the treated wastewater and biosolids that emerge from the medium.
The Moving Bed Biofilm Reactor has the same principle as the Submerged Aerated Filter or the Trickling Filter as to the type of microorganisms that grow in the tank (those that form a biofilm on a support medium). The difference is that, in this case, the support is a set of carriers that move freely in the aeration or anoxic tank. The MBBR is used when the wastewater does not have a very high concentration of pollutants but requires a high quality of treated water and there is a strong restriction of space.
The Membrane Biological Reactors have the same principle as conventional activated sludge systems. However, the sludge is separated by the water filtration in membranes, instead of being separated by a settler as in the activated sludge process. This allows a significantly more efficient liquid-sludge separation. The MB reactors are recommended when there is a strong space limitation and, the treated water quality is highly strict because of its utilization in direct-contact activities with humans.