Technologies Adopted
Extended Aeration is a type of activated sludge process with primary settling. It is most commonly used treatment system in small developments and resorts. In an extended aeration (EA) system, sewage is brought into a biological basin where it is degraded by naturally occurring bacteria. After an “extended” period of time, typically 24 hours of detention time, the mixed liquor (ML) is sent to a clarifier where it is allowed to settle. The retention time will be very long in order to generate less sludge. Secondary effluent (SE) is drawn off the clarifier and the settled biomass is returned to the head of the plant.
To maintain a constant mixed liquor concentration, a certain amount of the settled biomass is wasted (WAS) out of the plant, typically to an aerated sludge holding tank or digester.
To improve the efficiency of treatment, an anoxic zone, or un-aerated zone, is often placed at the head of the biological basin. This zone allows for de- nitrification, which helps to moderate the pH, as well as provides a better settling biomass. The whole process is aerobic and the BOD removal efficiency is higher than activated sludge process that makes it desirable to use where it is to be followed by tertiary treatment for reuse. A flow diagram of this treatment technique is shown below.
An Assured Future Process Schematics For Sewage Treatment Plant
The sequencing batch reactor (SBR) process is a sequential suspended growth (activated sludge) process in which all major steps occur in the same tank in sequential order. The complete five phases take place in single reactor thus reduces the footprint. SBRs can be designed and operated to enhance removal of nitrogen, phosphorus, and ammonia, in addition to removing TSS and BOD. The five stages of SBR are:
- FILL: Wastewater fills the tank, mixing with biomass that settles during the previous cycle.
- REACT: Air is added to the tank to aid biological growth and facilitate waste reduction.
- SETTLE: Mixing and Aeration stop during this stage to allow solids to settle.
- DRAW: Clarified effluent is discharged.
- IDLE: Sludge can be removed during this stage.
Merits Of Technology
- Lower installed cost than "Conventional" methods.
- Less land space required for SBR treatment plants.
- Consistent high-quality, low nutrient level effluent.
- Tolerates wide swings in flow and organic loading.
- No clarifier required.
- Better control over filamentous growth and settling problems.
- Nutrient removal without chemicals - nitrification and de-nitrification, phosphate removal.
- Simple sludge process management.
- Less equipment to service and maintain.
- Existing plants can often be converted to SBR process.
- Less operator attention than "Conventional" processes.
Seamak's innovative MBR system is a progression of the company's proven sewage treatment technology for handling grey and black waste water. Membranes act as a barrier to bacteria and suspended solids to produce a low turbidity treatment plant effluent with very low bacteria counts.
MBR is the combination of a membrane process like microfiltration or ultra filtration with a suspended growth bioreactor. This very compact arrangement produces a MF/UF quality effluent suitable for reuse applications or as a high quality feed water source for Reverse Osmosis treatment. The MBR process can be employed in activated sludge processes, using the membranes as liquid-solid separation instead of the usual settling. It has high separation property due to trans-membrane pressure, blocks sludge & large molecules in the membrane letting clear water to permeate through.
MBR PROCESS
- Pre-Treatment
- Pre Screen
- Oil & grease removal
- Sand removal & fine screen
- Bio Reactor
- Submerged membrane/Airlift membrane
- Air blowers diffuse air to the wastewater
- Balance sludge discharge through pump
- Clear water will be permeated out by self priming pump at vacuum pressure through MBR Modules.
MERITS OF TECHNOLOGY
- Higher effective Bio reaction
- Good resistance of impact of Shock loads
- High quality outlet water
- Reduced Footprint with aesthetic appearance
- Long age of the sludge
- Process automation by PLC system
- Control over HRT & SRT
- High degree of disinfection.
Seamak's Moving Bed Bio-Reactor (MBBR) technology is based on the bio-film principle with an active bio-film growing on smallspecially designed plastic carriers that are kept suspended in the reactor. It is one of the advanced biological treatment processes which have a great potential for the simultaneous and efficient removal of nutrients along with organic matter. It is a process coupling suspended activated sludge and attached growth process in a single system. The technology utilizes the advantages of both activated sludge and other bio-film systems (e.g. bio-filters, bio-rotors etc.) without being controlled by their disadvantages. The carriers are designed in such a way that it provides a large protected surface area for the bio-film and optimal conditions for the bacteria culture while suspended in the water.
It is also known as Fluidized Bed Bio Reactor. In fluidized bed bioreactors the wastewater is fed upward to a bed of 0.4 to 0.5 mm sand or activated carbon. The bed depths are in the range of 3 to 4 m with the specific surface area of about 100 m2 / m3 of the reactor volume. Up flow velocity is 30 to 36 m/h. The hydraulic retention time in the FBBR is ranging from 5 to 20 min. For aerobic applications re-circulated effluent is passed through an oxidation tank to pre dissolve oxygen.
Adding air to the FBBR would discharge packing to the effluent. For wastewater treatment, FBBRs have been used mainly for the post de-nitrification. Aerobic FBBRs are frequently used to treat groundwater contaminated with hazardous substances.
MERITS OF TECHNOLOGY
- Clog free operation
- High bio surface area.
- Make bio system extremely compact.
- No sludge return system needed.
- Effective under extremely high BOD loading.
- Less sensitivity to shock loading.
- High effluent quality.
- Small footprint, simplicity of design, installation & operation
- Design flexibility, easy affordable up-gradation
- No backwash needed & low maintenance
- Easily retained media with long life
Submerged Aerobic Fixed Film Reactor is a cost-effective method of wastewater treatment and sewage sanitation that is primarily used in residential and commercial complexes. This equipment primarily works on the three stages; thatare Primary Treatment, Secondary Treatment and Final Treatment / Clarification. SAFF Technology is one of the simplest and most cost effective methods of commercial and residential sewage sanitation/wastewater treatment, particularly for small to medium sized treat-ment plants. A well built Submerged Aerated Filter plant has no moving parts within its main process zones, any functional items will be positioned to access easily without disrupting the ongoing sewage treatment.
The three stages of SAFF are
- Primary Settlement
- Here the larger solids settle into the bottom of the
- primary tank and are removed periodically as sludge,
- Also, the materials floating upwards is removed by a screening method.
- Secondary Treatment
- Aeration of wastewater with flocculating biological growth, followed by separation of treated wastewater from this growth. Aeration is done intermittently using diffusers which helps in reducing BOD/COD of the sewage.
- Fluidized suspended media circulates within a basin, and the bio-media is engineered in a wheel shape & is buoyant, allowing water flow to circulate the media throughout the vessel. It has High Bio-Surface area(300-850m2/m3) and the bio media design allows aggressive sloughing action thus maintaining a productive layer of biological growth.
- Final Settlement / Clarification
- Where remaining solids (Humus) are settled out of the biological treated effluent.
MERITS OF TECHNOLOGY
- Clog free operation
- High bio surface area.
- Make bio system extremely compact.
- No sludge return system needed.
- Effective under extremely high BOD loading.
- Less sensitivity to shock loading.
- High effluent quality.
- Small footprint, simplicity of design, installation & operation
- Design flexibility, easy affordable up-gradation
- No backwash needed & low maintenance
- Easily retained media with long life
For Residential & Commercial
Seamak with its expertise in wastewater treatment plants offers Customized Packaged Plant, a single supply of unit for the treatment of sewage water for apartments, commercial complexes, hotels, colleges etc. The advanced pre-engineered design combined with prefabricated structures gives an edge over the conventional systems with respect to installation cost and time along with its ease in usability. The Packaged Plants, designed in the range of 10 KLD to 200 KLD, gives output of superior quality water which can further be reused for flushing and gardening as per the Pollution Control Board standards.
WHY PACKAGED PLANTS?
- Low cost of construction and easy Installation
- Advanced Pre-engineered design with prefabricated structure.
- Easy to use and requires less manpower
- Long Service life and easy maintenance
- Customized design as per requirement
TECHNOLOGY
The technology is based on the bio-film principle with an active bio-film growing on small specially designed plastic carriers that are kept suspended in the reactor. The carriers are designed in such a way that it provides a large protected surface area for the bio-film and optimal conditions for the bacteria culture while suspended in the water.
