logging in or signing up SEWAGE srichemist Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: Embed: Flash iPad Dynamic Copy Does not support media & animations Automatically changes to Flash or non-Flash embed WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 906 Category: Education License: All Rights Reserved Like it (0) Dislike it (0) Added: October 14, 2010 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Sewage and Effluent Treatment : Sewage and Effluent Treatment SRIRAM V LECTURER IN CHEMISTRY KNCET THOTTIAM Slide 2: What is Sewage or Wastewater? • Liquid wastes containing a variety of pollutants in suspension and solution – Eight General Categories of Water Pollutants •Oxygen Demanding Wastes (Biodegradable Organics) •Disease Causing Agents (pathogens and parasites) •Nutrients • Synthetic Organic Compounds (SOCS) • Inorganic Compounds and minerals (IOCS) • Sediment •Radiation •Heat Slide 3: Two General Types of Sewage 1) Sanitary or “Domestic” Sewage Combination of Human and Animal excreta (feces and urine) (“black water”) and “gray water” from washing, bathing and cooking. Human excreta: 100 – 500 g wet weight feces / day 1 – 1.3 l urine / day Slide 4: Domestic Sewage Composition • Protein: (40 – 60%) • Carbohydrates: (25 – 50%) • Fats & Oils ( ~ 10% ) •High in microorganisms, High in organic materials Slide 5: 2) Storm Sewage – Runoff. Carries excreta of animals, fecal matter Other organisms, organic material (leaves, detritus) as well as minerals and metals. Slide 6: Wastewater Solids: density particle size level of Volatile Suspended Solids Biochemical Oxygen Demand Temperature Ammonia Nutrient levels Slide 7: Wastewater Treatment Considerations Objective: to maintain or improve the quality of the receiving body of water Treatment stages: Preliminary Primary Secondary Tertiary Slide 8: CLASSIFICATION Slide 9: Sewage Treatment Primary: Physical Screening or “Bar Filters” Removal of “large” materials Grinding Grinding and sedimentation of “larger” materials Removal from Grit chamber Primary Sedimentation Tanks Decrease velocity of sewage Sedimentation of “suspended solids” Biosolids (sludge) removed from bottom Low density material float (fats, oils) Removed from surface by skimmer arm Slide 10: Primary Treatment • Physical Processes • Removes 45 to 85% of solids • Removes about 25 to 50% BOD Slide 11: Primary sedimentation (bar screens) Slide 12: Secondary: Primary + Biological A) Bio solids from sedimentation and skimming Organic Compounds - Methane Complex Organic Molecules Monomers Slide 13: Skimmer Slide 14: Flow of sewage Slide 15: • B) Liquid Effluents from Primary Sedimentation Tanks – Contains soluble organic materials • i) Trickling Filters • ii) Rotating Biological Contactors (RBC’s) •iii) Activated Sludge Processes Slide 16: Secondary – Liquid Phase • Trickling Filters –Effluent is sprayed over a bed of filter media, consisting of limestone, granite or plastic – The media develops a “biofilm” consisting of Bacteria, fungi, algae, protozoa, rotifers and various macro invertebrates Slide 17: Secondary – Liquid Phase Activated Sludge – Employs an Aeration Tank – Mix effluent with a slurry (liquor) of bacteria & water – Aerate vigorously – Produces “floc” of Biomass – > 300 strains of Bacteria Slide 18: Secondary treatment Slide 19: Secondary treatment Slide 21: Secondary / Tertiary – Liquid Phase Rotating Biological Contactors (RBC’s) Series of plastic discs mounted on a horizontal shaft that rotate slowly through liquid phase wastewater ~ 40% submerged Develop a biofilm further reduce BOD and ammonia Slide 22: Tertiary Treatment • Liquid Phase • Final Sand Filtration •Further reduces BOD upto 90% Slide 23: Tertiary treatment Slide 24: Tertiary treatment Disposal of treated sewage : Disposal of treated sewage Dumped under earth Incineration: into seas Fertilizer for agriculture Reuse of treated sewage Slide 26: disinfection Slide 27: Over all view You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.