Kinetics Study of a Suspended Growth System for Biological …
341
2 Materials and Methods
2.1 Collection of Real-Life Sample
Real-life sample of bakery and confectionery wastewater was collected from local
bakery and confectionery plants. The concerned bakery and confectionery plant use
large volumes of butter, flour, shortening, eggs, fillings of various types for production
of patties, sandwich, burger, pastry, cake, etc. The samples were collected at different
times from plant outlets and were analyzed for various characteristic parameters like
pH, COD, BOD, TSS, TDS, and ammoniacal nitrogen following the protocols as
described in American Public Health Association (2000).
2.2 Preparation of Simulated Feed Solution
Simulated feed solution was prepared for the purpose of acclimatization of microbial seed collected from nearby local sewage treatment plant. The constituents feed
solution consist of dextrose, peptone, beef extract, yeast extract, ammonium sulfate,
ammonium chloride, dipotassium hydrogen phosphate, potassium dihydrogen phosphate as concentration of 12.5, 1.0, 0.8, 0.8, 0.4, 1.5, 1.0, and 1.0 g/L, respectively.
The stock feed solution was diluted as per requirement for maintaining COD and
ammoniacal nitrogen values of 1350 ± 50 and 70 ± 10 mg/L, respectively, during
seed acclimatization and batch kinetic study.
2.3 Seed Acclimatization for Carbon Oxidation
and Nitrification Study
The seed acclimatization study was carried out in a measuring cylinder of 1.0 L
capacity as a reactor. About 100 mL of nonacclimatized seed collected from nearby
local sewage treatment plants mixed with 700 mL of diluted simulated wastewater and 50 mL of micronutrient solution to make a total volume of 850 mL in the
cylinder. The micronutrient solution contains the following components (g/L), EDTA
0.01; ZnSO 4 ·7H 2 O 0.001; CaCl 2 ·2H 2 O 0.1; MnCl 2 ·2H 2 O 0.008; FeCl 3 ·6H 2 O 0.71;
(NH 4 ) 6 Mo 7 O 24 0.0011; CuSO 4 ·5H 2 O 0.001; CoCl 2 ·6H 2 O 0.2. The COD was maintained in the range of 1350 ± 50 mg/L and NH 4
+ –N was 70 ± 10 mg/L. Aeration
was done continuously by means of diffused air system with the help of aquarium
pumps. The acclimatization was continued for an overall period of 3 months. The
biomass growth was indicated by the magnitude of sludge volume index (SVI) and
MLSS concentration in the cylinder. pH in the reactor was maintained in the range
of 6.8–7.5 by adding required amount of sodium carbonate (Na 2 CO 3 ) and phosphate
buffer.
341
2 Materials and Methods
2.1 Collection of Real-Life Sample
Real-life sample of bakery and confectionery wastewater was collected from local
bakery and confectionery plants. The concerned bakery and confectionery plant use
large volumes of butter, flour, shortening, eggs, fillings of various types for production
of patties, sandwich, burger, pastry, cake, etc. The samples were collected at different
times from plant outlets and were analyzed for various characteristic parameters like
pH, COD, BOD, TSS, TDS, and ammoniacal nitrogen following the protocols as
described in American Public Health Association (2000).
2.2 Preparation of Simulated Feed Solution
Simulated feed solution was prepared for the purpose of acclimatization of microbial seed collected from nearby local sewage treatment plant. The constituents feed
solution consist of dextrose, peptone, beef extract, yeast extract, ammonium sulfate,
ammonium chloride, dipotassium hydrogen phosphate, potassium dihydrogen phosphate as concentration of 12.5, 1.0, 0.8, 0.8, 0.4, 1.5, 1.0, and 1.0 g/L, respectively.
The stock feed solution was diluted as per requirement for maintaining COD and
ammoniacal nitrogen values of 1350 ± 50 and 70 ± 10 mg/L, respectively, during
seed acclimatization and batch kinetic study.
2.3 Seed Acclimatization for Carbon Oxidation
and Nitrification Study
The seed acclimatization study was carried out in a measuring cylinder of 1.0 L
capacity as a reactor. About 100 mL of nonacclimatized seed collected from nearby
local sewage treatment plants mixed with 700 mL of diluted simulated wastewater and 50 mL of micronutrient solution to make a total volume of 850 mL in the
cylinder. The micronutrient solution contains the following components (g/L), EDTA
0.01; ZnSO 4 ·7H 2 O 0.001; CaCl 2 ·2H 2 O 0.1; MnCl 2 ·2H 2 O 0.008; FeCl 3 ·6H 2 O 0.71;
(NH 4 ) 6 Mo 7 O 24 0.0011; CuSO 4 ·5H 2 O 0.001; CoCl 2 ·6H 2 O 0.2. The COD was maintained in the range of 1350 ± 50 mg/L and NH 4
+ –N was 70 ± 10 mg/L. Aeration
was done continuously by means of diffused air system with the help of aquarium
pumps. The acclimatization was continued for an overall period of 3 months. The
biomass growth was indicated by the magnitude of sludge volume index (SVI) and
MLSS concentration in the cylinder. pH in the reactor was maintained in the range
of 6.8–7.5 by adding required amount of sodium carbonate (Na 2 CO 3 ) and phosphate
buffer.