Citation: Rajkumar K (2016) $Q(YDOXDWLRQRI%LRORJLFDO$SSURDFKIRUWKH(IÀXHQW7UHDWPHQWRI3DSHU%RDUGV,QGXVWU\$Q(FRQRPLF3HUVSHFWLYH J %LRUHPHGLDW%LRGHJUDG 366 GRL 366
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microbes [16]. There are different types of bacteria (Psychrophiles exist at 5°C-35°C, Mesophile at 25°C-40°C and Thermophiles at 25°C-75°C) depending on the temperature range. Figure 3 shows that the range of temperature observed during the one month study of wastewater characteristics fall between 25°C - 30°C. pH: pH of wastewater is very important to be monitored as it determines the feasibility of a particular sample to be biologically treated [17,18]. Biological treatment can be suitably applied to wastewater only if pH values are near neutral. Acidic and basic character of the wastewater has negative effect on the microorganisms and thus leads to inefficient treatment [19]. The normal pH in wastewater for bacterial survival is 5 to 9. But, neutral pH i.e., about 6.5-7.5 is required for the optimum activity of the bacteria. If the pH is in acidic range fungi can become predominant than the bacteria which will results in poor settling. If the pH is too high it will affect the metabolic activity of the microbes which directly affects the treatment process [20]. For bacteria there is an orderly increase in growth rate between the minimum and maximum pH. Figure 4 showed that the levels of pH in the conversional treatment process influent and treated effluent range between 6.6 to 7.6 and 6.8 to 7.5 respectively. The additions of coagulants (non-ferric alum) depress the wastewater pH to a lower or higher value. The decrease in pH after the addition of coagulant may be due to the several hydrolytic reactions, which are taking place during coagulation, forming multivalent charged hydrous oxide species and
generating H 3 O + ion during each step, thus reducing the pH value [21]. It has also been reported that the coagulant addition depresses pH to highly acidic levels, as the coagulant dose is highly correlated with pH [22]. It is supposed that improvement of flocculation pH may reduce the alum dose needs for the optimization of the process. It can be said that the highest range of pH exists between 6.0 and 8.0, beyond which the effluent quality deteriorates. Effluent flow rate: The effluent flow rater and hydraulic react time is induced the performances of the process and the desired degree of treatment. It is an important parameter because industrial persons cannot hold their wastewater within their premises for longer period. Figure 5 clearly shows that the flow rate of the influent 4396 m 3 /d (Max) and 1816 m 3 /d (Min) and treated effluent 3232 m 3 /d (Max) and 1456 m 3 /d (Min), respectively. The maximum and minimum input of influent not affects the treatment process. Wastewater aeration time, usually expressed in hours, is based on the time required by the micro- organisms to degrade the organic load present therein. Table 3 shows that the hydraulic react time of each system. Dissolved Oxygen (DO): Dissolved oxygen supplying with 22 kw surface fixed aerators in conventional aeration take (6 Nos) and extended aeration tank (2 Nos). DO is required by the microorganisms to respire properly in aeration tank (Figure 6). Too much oxygen adds unnecessary cost due to increased power consumption and too little
System Condition Effective volume ,QÀXHQWÀRZUDWH
Levels 4000 m 3
165 m 3 +U
+57
+U 06 Jul
S+
'LVVROYHG2[\JHQ
2-4 mg/L
,QÀXHQW%2' ,QÀXHQW&2'
200-300 mg/L 1000-2500 mg/L
MLSS
5000 mg/L 3000 mg/L
MLVSS
Table 2: 2SHUDWLRQFRQGLWLRQRIWKHFRQYHQWLRQDOWUHDWPHQWSURFHVV
Effluent flow (m3/Day) Treated effluent flow (m3/Day)
5000
4000
3000
2000
1000
0
1 3 5 7 9 1113151719212325272931 Days
Figure 5: Variation in the LQÀXHQWDQGWUHDWHGHIÀXHQWÀRZUDWHIRUWKH period of study.
J Bioremediat Biodegrad ISSN: 2155-6199 JBRBD, an open access journal
Volume 7 • Issue 5 • 1000366
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