Page 25 - March 2020 - WT Site

Good plant life and lesser maintenance problems. Cost-wise it is comparison of SBR with other biological treatment for removal
very high. It is represented in Fig-5 [8]. In mechanically operated of organic content and Nutrient removal [9-47].
decanters there are various types like moving weir decanters,
crown decanters, etc.

Fig-5: Mechanically operated decanter

2.3. Advantages of SBR over other technologies:

• Completely automatic
• The regular time-based changes in operation necessitate
automation

• Automation includes-Opening and closing of Gates, Valves
o Operation of Pumps, Decanters dissolved Oxygen control
through VFD based blower operation

• The plant can be remotely monitored
Fig-6: Removal efficiencies in SBR for (a) BOD (b) COD
• Plant operation is independent of operator capability (c) Phosphorus (d) Nitrogen

• Conventional plants like ASP, MBBR, UASB are normally S.NO PARAMETER SBR OTHER AEROBIC
TECHNOLOGIES
manually operated. Lack of qualified manpower affects 1 BOD <10ppm <20ppm
performance.
2 Suspended solids <10ppm <30ppm
• Electrical consumption will be lower when compared to 3 Total Nitrogen <10ppm No treatment
conventional systems as blowers will not run continuously, No treatment
and they run only in designated intervals. 4 Total Phosphorous <1ppm
Table-1: Comparison of other technologies
2.4. Performance Evaluation:
2.5. Market Status:
Sequential batch reactors compete with other technologies with
their promising removal of pollutants like BOD, COD and Sequencing batch reactors are operated using different aeration
nutrient removal. Besides the removal of BOD with the aerobic systems and decanters. Installations in India are mostly found to
system, if anaerobic conditions are also maintained COD removal be applied for sewage treatment applications. The existing plants
will be significant. Nitrification, denitrification and biological in India are known to operate with diffused aeration systems and
phosphorous removals are also proven in SBR. COD and BOD mechanically operated decanters. SBR operation is in a double tank
removals were >95% in most of the studies with SBR. However, process with the automatic operations are seen most in India. The
for nitrogen and phosphorus removals were below 80% in most application of SBRs in India has been demonstrated in Fig-7. SBRs
of the studies as shown in the Fig-6(a-d). Table-1 shows the have been applied mostly in sewage treatment plants (STP) in India.

Water Today - The Magazine l March 2020 27