Isolation and characterization of bacteria from extended aeration wastewater treatment plants / Randy Chin Kok Fei

• Main Author: Chin, Randy Kok Fei
• Format: Thesis
• Published: 2010
• Subjects: Q Science (General); QH301 Biology
• Online Access: http://studentsrepo.um.edu.my/3549/4/Title_page%2C_abstract%2C_table_of_contents.pdf; http://studentsrepo.um.edu.my/3549/5/Full_chapters.pdf; http://studentsrepo.um.edu.my/3549/6/References.pdf; http://www.pendeta.um.edu.my/uhtbin/cgisirsi/x/0/0/57/5/3?searchdata1=851717{CKEY}&searchfield1=GENERAL^SUBJECT^GENERAL^^&user_id=WEBSERVER; http://studentsrepo.um.edu.my/3549/

In this study, three different wastewater treatment plants (STP1, STP2 and STP3) were sampled in Klang Valley. STP1 exhibited the best activated sludge health with healthy Sludge Volume (SV), Mixed Liquor Suspended Solids (MLSS) and Mixed Liquor Volatile Suspended Solids (MLVSS). STP2 were constantly disrupted by the mechanical failures which caused its dissolved oxygen (DO) to decrease whereas STP3 was troubled by the inadequate alkalinity in its mixed liquor causing acidic condition in aeration tank. The acidic condition resulted in pin-floc problem and contributed to high Total Suspended Solids (TSS) and low SV. Influent at STP3 was also found to contain high amount of Copper (Cu) and Lead (Pb). The nutrient removal efficiency was also the highest in STP1 compared to STP2 and STP3. In the enumeration of heterotrophic bacteria, STP1 had higher cfu counts with an average of 3.19±1.21×106 cfu ml−1 as compared to STP2 (1.85±2.00×106 cfu ml−1) and STP3 (2.72±5.40×105 cfu ml−1). Some of the common bacteria cultivated from the activated sludge of this study are Stenotrophomonas maltophilia, genus Acidovorax, genus Aeromonas, genus Staphylococcus and genus Bacillus. STP1 was dominated by γ-Proteobacteria with 44% (n=22) whereas STP2 and STP3 were dominated by β-Proteobacteria with 42% (n=21) and 40% (n=16) respectively.