Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Biotechnology in Industrial Waste water Treatment


Published on

Published in: Technology

Biotechnology in Industrial Waste water Treatment

  2. 2. Contents  Introduction  Benefits  Industrial Contaminants & their Impact  Treatment Technologies  Bioremediation Technology  Bioremediation Principles & Mechanism  Factors Influencing Bioremediation  Advantages & Disadvantages of Bioremediation  Conclusions
  3. 3. Industrial Wastewater Characteristics Industrial wastewater is a type of wastewater produced by industrial activity, such as that of factories, mills and mines. It is characterized by its large volume, high temperature, high concentration of biodegradable organic matter and suspended solids, high alkalinity or acidity, and by variations of flow. The degree of treatment varies according to the means of disposal, which may be to a municipal sewer system, a receiving body of water, such as a stream, an estuary, or a large body of fresh water, or recovery for reuse.
  4. 4. Benefits  Used to develop method for the treatment of toxic compounds.  Improving the design and operation of biomechanical treatment system used for degradation of toxic compounds.  Improvement of public health, sanitation, soil integrity and the conservation of fresh water resources.
  5. 5. How to accomplish waste Treatment  Trickling Filter  Rotating Biological Contactor  Activated Sludge Process  Lagoons  Oxidation Ponds
  6. 6. Major Players  Microorganisms are used to destroy waste materials.  Microorganisms include:  Bacteria (aerobic and anaerobic)  Fungi  Algae  Actinomycetes (filamentous bacteria).
  7. 7. Overall Treatment Processes
  8. 8. 3 stages of treatment. Primary. This is only a physical separation to remove solid matter. Effluent is allowed to settle for a few hours. Secondary. The organic and nutrient load is decreased by microbial activity Up to 95% so that the effluent is of a quality to be able to go into rivers. Tertiary. This is a complete treatment, but it is very expensive and not used much.
  9. 9. . Secondary Treatment Can be divided into 1.Anaerobic 2. Aerobic treatment processes
  10. 10. Anaerobic Complex series of digestive and fermentative reactions by a mixture of bacteria. It can remove 95% BOD. This is the choice if there is a lot of insoluble matter cellulose, industrial waste. Degradation is carriead out in large tanks – sludge digestors or bioreactors. Molecular components are digested and fermented to FA, H 2, CO2. FA then to acetate, CO2 and H2. These are substrates for methanogenic bacteria to make methane. Major products are methane and CO2. Used or burnt off.
  11. 11. Anaerobic Sludge Digester
  12. 12. Anaerobic sludge digestion
  13. 13. Anaerobic sludge digestion
  14. 14. Aerobic There are several kinds of aerobic decomposition processes. Trickling filter and activated sludge are the most common. Trickling filter is a bed of crushed rock, ~2m thick. Wastewater is sprayed on the top (UWI plant). Liquid slowly passes through the rock, organic matter absorbs to the rock and microbial growth takes place. Complete mineralization of organic matter takes place. Most common is activated sludge. Wastewater is mixed and aerated in a large tank
  15. 15. Trickling Filter
  16. 16. Trickling Filter
  17. 17. Aeration tank, activated sludge
  18. 18. Aeration Tank
  19. 19. Bioremediation Technology Bioremediation is the use of micro-organism metabolism to remove pollutants. Technologies can be generally classified as in situ or ex situ. In situ bioremediation involves treating the contaminated material at the site, while ex situ involves the removal of the contaminated material to be treated elsewhere
  20. 20. Bioremediation Technology  Bioreactors technologically are the most sophisticated category of environmental bioremediation.  Bioreactors offer a much faster means of waste biodegradation than land treatment and more control over reaction conditions and effluent quality than simple biofilters.
  21. 21. Biological Treatment Process 1. The microorganisms are used to convert the organic matter (colloidal and dissolved) into various gases and into cell tissue. 2. The contaminant of organic substances is ingested and digested as food along with other energy source by the cell. GOAL: Degrade organic substances that are hazardous to living organisms and convert the organic contaminants into inert products. Microorganisms eat organic contaminant Microorganisms digest and convert waste to CO2 and H2O Microorganisms give off CO2 and H2O
  22. 22. Factors Influencing Bioremediation For bioremediation of harmful chemicals following factors are required to be monitored in the effluent:  Required microorganism  Temperature  pH level  Dissolved oxygen concentration  Inorganic nutrient. These conditions allow microbes to grow and multiply—and eat more chemicals. When conditions are not right, microbes grow too slowly or die or they can create more harmful chemicals.
  23. 23. Activated Sludge
  24. 24. Microbial activity in activated sludge. Slime forming bacteria like Zoogloea grow and form flocs. Small animals and protozoa attach to these. Process of oxidation is similar to the trickling bed. Effluent containing flocs goes to settling tanks. Flocs settle. Some floc material is recirculated. Water spends 5-10 hours in sludge tank, too short for complete oxidation. Main process is absorption of organic matter to the floc. BOD of liq waste is reduced by ~95%. Most BOD is in the flocs. BOD reduction then takes place by digestion of the flocs in the sludge digestor.
  25. 25. Oxidation ponds or lagoons. This is very simple treatment used in rural areas, particularly suited for tropical areas (Portmore sewage treatment Plant). Take up a large area, are less than 3m deep (allow light to penetrate). There are odour problems and the process can take over a week. Three components are essential for the functioning of the oxidation pond. They are:    Bacteria Algae Sunlight
  26. 26. Oxidation ponds or lagoons.  The bacteria in the pond oxidise the various organic material producing carbondioxide, ammonia and water.  The algae grow by utilizing the inorganic material and carbon dioxide in the presence of sunlight.  The oxygen requirement for oxidation of the organic matter by bacteria is satisfied mainly by oxygen released by the algae. Also some oxygen is provided by the contact with the atmosphere. Sunlight is an important factor in the functioning of the oxidation pond
  27. 27. Lagoon
  28. 28. Comparing advantages. Anaerobic treatment has advantages over aerobic.  Reduction of excess sludge production up to 90%  Production of energy in the form of methane gas  No or very little use of chemicals  Lower treatment costs  High flexibility, since it can be applied to very different types of effluents (higher and lower loading rates, mesophilic or thermophilic conditions, more or less complex wastewaters, etc.)  Anaerobic organisms can be preserved unfed for a long time, which makes it possible to treat wastewaters that are generated with longer (seasonal production) or shorter (holidays and weekends) pauses in between .
  29. 29. Conclusions      Bioremediation continues to be the favored approach for processing biological wastes. Bioremediation utilizes microbes such as bacteria, fungi, yeast, algae, and some plants. Three categories of bioremediation techniques have been identified: in situ land treatment (treatment of contaminated material on site), biofiltration, and bioreactors. Bioremediation is highly efficient system, if proper conditions are maintained example pH, temperature, nutrients. Bioremediation is cost-efficient and helps chemical and physical methods of managing wastes and environmental pollutants.