02-02-2012, 12:08 PM
EARTH AND HEALTH
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SEQUENCING BATCH REACTOR (SBR) :
It is an unique process used in treatment of waste water (sewage).
This treatment process is first proposed by two environmentalists Metcalf and Eddy in 1991.
Operationally SBR is extremely flexible in its ability, while physically it is very simple.
CONCEPTS USED IN SBR:
1.ACTIVATED SLUDGE PROCESS:
Activated sludge is a settled precipitate of sewage consisting micro organisms. It is very active and used in treating fresh sewage.
Activated sludge is a process in sewage treatment in which air or oxygen is forced into mixed liquor (activated sludge + raw sewage) to develop a biological floc which reduces the organic content of the sewage
2.BACTERIAL SEEDING:
It is a process of adding of activated or return sludge to raw sewage effluent.
It is done in two ways:
(1) Addition of sludge from the re-circulation line of similar operating plant and,
(2) Addition of cow dung or other natural manure.
3.DIFFUSED AERATION PROCESS:
Diffused aerators add air to wastewater, increasing dissolved oxygen content and supplying microorganisms with oxygen necessary for aerobic biological treatment.
Air is pumped through the blocks, oxygenates the mix and provide the necessary mixing action.
4. ACCLIMATISATION OF MICROBIAL CULTURE:
Acclimatisation is the time required for the microbial culture to get accustomed to the conditions present in the particular wastewater treatment plant .
The time required for acclimatisation depends primarily on the factors like BOD and COD values, DO, pH, temperature, micronutrients, etc
PARAMETERS TO JUDGE OPERATIONAL EFFICIENCY OF SBR:
There are several indications of change that warn the operator of impending trouble. The problem can be correctly identified by the following parameters and the most appropriate action taken.