Preview

Activated Sludge Process

Better Essays
Open Document
Open Document
1110 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Activated Sludge Process
Activated Sludge Process
The activated sludge process is a wastewater treatment method in which the carbonaceous organic matter of wastewater provides an energy source for the production of new cells for a mixed population of microorganisms in an aquatic aerobic environment. The microbes convert carbon into cell tissue and oxidized end products that include carbon dioxide and water.
Activated sludge plant involves wastewater aeration in the presence of a microbial suspension, solid-liquid separation following aeration, discharge of clarified effluent, wasting of excess biomass, and return of remaining biomass to the aeration tank. An important feature of the activated sludge-process is the formation of flocculent settleable solids that can be removed by gravity settling in sedimentation tanks. In activated sludge process wastewater containing organic matter is aerated in an aeration basin in which micro-organisms metabolize the suspended and soluble organic matter. Part of organic matter is synthesized into new cells and part is oxidized to CO2 and water to derive energy. In activated sludge systems the new cells formed in the reaction are removed from the liquid stream in the form of a flocculent sludge in settling tanks. A part of this settled biomass, described as activated sludge is returned to the aeration tank and the remaining forms waste or excess sludge.
Activated Sludge Treatment Process Layout: Biological Nutrient Removal Process
BNR processes are modifications of the activated sludge process that incorporate anoxic and anaerobic zones to provide nitrogen and phosphorous removal.
In aerobic zones, oxygen is the electron acceptor, in anoxic zones, nitrate-N is the electron acceptor and in anaerobic zones neither oxygen nor nitrate-N is present. The division of the bioreactor to provide these alternative biochemical environments is the distinguishing feature of a BNR system. The aerobic zone is a necessary component of all BNR systems, while the

You May Also Find These Documents Helpful

  • Good Essays

    The District of Columbia Water and Sewer Authority receives and treats wastewater collected from the District of Columbia sewer system and from the Maryland and Virginia suburbs. The treatment has two phases, in the first phase begins as debris and grit which is removed and trucked to a landfill where the sewage then flows into primary sedimentation tanks that separate the solids from liquids. The second phase is where oxygen is bubbled into treatment tanks so microbes can break down organic matter. Then the microbes convert ammonia into harmless nitrogen gas. Residual solids are settled out and the water is…

    • 928 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Physiological Reactions and Motility Test Results. All of the possible unknowns were of the family Enterobacteriaceae, and thus, performed similarly on a number of tests. All organisms evaluated were facultative anaerobes, showing densest growth at the top of the fluid thioglycolate medium with lessening growth moving down the tube. This oxygen requirement is consistent with the conditions of the intestines, where enteric bacteria are found. Facultative anaerobes generate superoxide ions whenever they respire aerobically and use oxygen as a terminal electron acceptor. The superoxide ion, which is extremely reactive, is converted to H2O2 by the enzyme superoxide dismutase following the equation 2O2- + 2H+ → H2O2 + O2. Catalase must then break down H2O2, which is also a reactive oxygen species, according to the equation 2H2O2 → 2H2O + O2. All enteric bacteria in this experiment tested positive for catalase activity, showing bubbling when added to H2O2, indicating that O2 (and water) were being released. Although enteric bacteria use oxygen as a terminal electron acceptor, tests for oxidase activity indicated that they possess terminal oxidases other than cytochrome c oxidase. That is, the oxidase reagent did not change from pink to purple when it came in contact with any of the organisms, indicating a negative result. Instead of oxygen, some facultative anaerobes employ nitrate as a terminal electron receptor; the nitrate broth was used to test for nitrate to nitrite…

    • 1937 Words
    • 8 Pages
    Good Essays
  • Powerful Essays

    5. Waste water treatment process: get water, drain out sludge, have sludge area, water goes through process to get more sludge out, water gets aerated, water gets filtered with Cl to remove bacteria.…

    • 2460 Words
    • 10 Pages
    Powerful Essays
  • Good Essays

    Secondary sewage treatment promotes the biological transformation of dissolved organic matter to microbial mass and carbon dioxide. They remove 75-95% of the BOD and many bacterial pathogens are removed by this process which will ultimately increase dissolved oxygen. Under some toxic conditions, the dissolved organic matter will be transformed into additional microbial biomass plus carbon dioxide. When the microbial growth is completed, under ideal conditions microbes will aggregate and form a stable structure which can then be removed (Cooke, n.d.).…

    • 517 Words
    • 2 Pages
    Good Essays
  • Good Essays

    Step 1- Nitrogen Fixation- Special bacteria convert the nitrogen gas (N2 ) to ammonia (NH3) which the plants can use. Step 2- Nitrification- Nitrification is the process which converts the ammonia into nitrite ions which the plants can take in as nutrients. Step 3- Ammonification- After all of the living organisms have used the nitrogen, decomposer bacteria convert the nitrogen-rich waste compounds into simpler ones. Step 4- Denitrification- Denitrification is the final step in which other bacteria convert the simple nitrogen compounds back into nitrogen gas (N2 ), which is then released back into the atmosphere to begin the cycle again.…

    • 837 Words
    • 4 Pages
    Good Essays
  • Satisfactory Essays

    Microbio

    • 3284 Words
    • 14 Pages

    3. Which of the following is a nitrifying microbe? A. Rhizobium B. Nitrobacter C. Pseudomonas D. Nostoc E. Azotobacter…

    • 3284 Words
    • 14 Pages
    Satisfactory Essays
  • Good Essays

    Bottled Water Research Paper

    • 4276 Words
    • 18 Pages

    Activated Alumina is a granulated form of aluminum oxide. In this process, water containing the contaminant is passed through a cartridge or canister of activated alumina which adsorbs the contaminant. The cartridge of activated alumina must be replaced periodically. Activated alumina devices can accumulate bacteria, so treated water may have higher bacteria counts than raw water.…

    • 4276 Words
    • 18 Pages
    Good Essays
  • Good Essays

    Anaerobic digestion is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen, used for industrial or domestic purposes to manage waste and/or to release energy.…

    • 796 Words
    • 4 Pages
    Good Essays
  • Powerful Essays

    Biotechnology In environment Clean up Process - APPSC G1 Mains - Paper 4 - Section 2 - Unit 3…

    • 6797 Words
    • 28 Pages
    Powerful Essays
  • Better Essays

    Bioremediation Outline

    • 1922 Words
    • 8 Pages

    E. Bioremediation did not become a well thought of science until about forty years ago when it had been given a new approach; to treat containments such as sludge from refineries.…

    • 1922 Words
    • 8 Pages
    Better Essays
  • Satisfactory Essays

    Thermosulfobacteria are also important in aerobic environments if they can rapidly reproduce in anaerobic environments. For example, in marine sediments and in aerobic wastewater treatment systems, sulfate reduction causes up to 50% of the mineralization of organic material. Also sulfate reduction stimulates microbially enhanced corrosion of metals.…

    • 363 Words
    • 2 Pages
    Satisfactory Essays
  • Powerful Essays

    Literature Review Methane

    • 1709 Words
    • 7 Pages

    In sanitary landfills, the process of burying waste and regularly covering deposits with a low permeability material creates an internal anaerobic environment that favors…

    • 1709 Words
    • 7 Pages
    Powerful Essays
  • Powerful Essays

    Adipic acid

    • 3850 Words
    • 16 Pages

    have implemented N2O abatement technologies (Reimer, 1999). As a result, nitric acid production is currently…

    • 3850 Words
    • 16 Pages
    Powerful Essays
  • Powerful Essays

    1. Determine physicochemical parameters for Palm Oil Mill Effluent (POME), fresh empty fruit bunch(EFB), and palm oil boiler ash. State the reference(s).…

    • 3195 Words
    • 13 Pages
    Powerful Essays
  • Good Essays

    Etp & Atp

    • 1092 Words
    • 5 Pages

    Industrial wastewater treatment covers the mechanisms and processes used to treat waters that have been contaminated in some way by anthropogenic industrial or commercial activities prior to its release into the environment or its re-use.…

    • 1092 Words
    • 5 Pages
    Good Essays

Related Topics