In addition, secondary treatment standards provide alternative standards established on a case-by-case basis for treatment facilities considered equivalent to secondary treatment (trickling filters and waste stabilization ponds). Waste water can be passed into rivers after sec­ondary treatment. Telephone: +353-53-47120 Fax: +353-53-47119 STAGE FOUR: FINAL TREATMENT treatment plants that receive less concentrated influent wastewater for combined and separate sewers. The Secondary Clarifiers are identical to the Primary Clarifiers; materials in the wastewater sink and float and rotating arms remove this material from the water. Sewage Treatment Unit-III 2. Secondary treatment is a step in wastewater treatment that involves the use of biological processes in order to capture all the dissolved organic materials that were not caught during the initial treatment. The secondary wastewater treatment process uses anaerobic microorganisms and retention time to breakdown and remove the remaining waste and other small particles. Secondary treatment is where waste is broken down by aerobic bacteria incorporated into the wastewater treatment system. Sewage Treatment 1. Primary treatment involves physical separation of sewage into solids and liquid by using a settling basin. In the tertiary treatment of sewage, the fluid from the secondary treatment process is cleansed of phosphate and nitrate ions that might cause pollution. Secondary sewage treatment is otherwise known as the biological process as microorganisms are utilized to treat the sewage. It is a biological method of treatment. In Secondary treatment the organic matter is decomposed by microorganisms and through sewage fungus by passing through water hyacinth pond, trickling filter method or activated sludge method. The sludge is placed in a landfill or at sea. Sewage treatment generally involves three stages > Primary > Secondary > Tertiary Treatment 5. Secondary Sewage Treatment. TREATMENT NL4NUALS PRIMARY, SECONDARY ANL TERTIARY TREATMENT document contains '3t pages . WASTE WATER TREATMENT MANUALS PRIMARY, SECONDARY and TERTIARY TREATMENT Environmental Protection Agency Ardcavan, Wexford, Ireland. Primary treatment is the first phase of sewage treatment: wastewater is placed in a holding tank and solids settle to the bottom where they are collected and lighter substances like fats and oils are scraped off the top. Primary or Physical Treat­ment: It is the process of removal of small and large, floating and sus­pended solids from sewage … In small sewage treatment plants, sludge is processed in a variety of ways including: aerobic digestion, storage in sludge lagoons, direct application to sludge drying beds, in-process storage (as in stabilization ponds), and land application. Secondary treatment or biological treatment-The primary effluent is passed into large aeration tanks where it is constantly agitated which allows vigorous growth of useful aerobic microbes into flocs. It improves wastewater quality before it is reused, recycled or discharged to the environment. 1. The microorganisms used in such a process are heterotrophic in nature; that means they do not synthesize their own organic materials and thus consume the organic constituents of sewage. This usually uses biological processes. The effluent from the primary settling tank is taken for secondary treatment. Thus aerobic microbes grow vigorously consuming a major part of the organic effluent reducing Biological Oxygen Demand (BOD) of the effluent. After treatment in the Secondary Clarifiers, the wastewater is now ready to be released to the Napa River, or further treated to produce recycled water. It involves in removal of large particles and floating materials such as leaves, papers, rags, solids such as sand, grit and oily substances. Other articles where Secondary treatment is discussed: wastewater treatment: Wastewater treatment and disposal: …as a first step before secondary treatment. After chlorination to remove its content of bacteria, the effluent from secondary treatment is returned to the local surface water. Secondary treatment Secondary treatment is designed to substantially degrade the biological content of the sewage such as are derived from human waste, food waste, soaps and detergent. Treatment for several hours reduces the microbial population significantly, and the clear fluid is removed for purification. What is Secondary Treatment? This stage involves the introduction of oxygen to the sewage and uses aerobic bacteria to break down the organic matter, coming mainly from human body waste, in the liquid part of the sewage. Secondary biological processes can be aerobic or anaerobic, each process utilizing a different type of bacterial community. 11.4 SECONDARY TREATMENT. The majority of municipal plants treat the settled sewage liquor using aerobic biological processes. Secondary treatment is an additional step in which wastewater effluent is treated to a higher quality before discharge to a disposal field and final infiltration into the soil. Ideally, this entire phase is carried out in the activated sludge component of the treatment plant, which is also known as the aeration tank. The rest of the water is moved to Secondary treatment. Secondary treatment consists of a biological process and secondary settling is designed to substantially degrade the biological content of the sewage such as are derived from human waste, food waste, soaps and detergent. , churning, floatation, screening and sedimentation system from sewage generation to effluent disposal secondary biological processes packaged system... 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