Download - BOD (Biochemical Oxygen Demand) ANALYSIS
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
1/11
BOD (Biochemical Oxygen
Demand) ANALYSIS
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
2/11
BOD
adalah prosedur kimia untuk menentukan jumlahoksigen terlarut yang dibutuhkan oleh organismebiologis aerobik dalam badan air untuk memecah
bahan organik yang ada dalam sampel air padasuhu tertentu selama periode waktu tertentu.
Ini bukan tes kuantitatif yang tepat, meskipunbanyak digunakan sebagai indikasi kualitas
organik air. paling sering disajikan dalam miligram oksigen
yang dikonsumsi per liter sampel selama 5 hariinkubasi pada 20 C
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
3/11
The organic material broken down bymicroorganism/bacteria :
HaObCnNc+ B+ (n+a/4 - b/2 c) O2
nCO2+ (a/2 3/2 c) H2O + cNH3
B:bacteria
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
4/11
BOD Test Procedure
Untuk memastikan bahwa semua kondisi lain
adalah sama, jumlah yang sangat kecil dari
benih mikro-organisme ditambahkan ke setiap
sampel yang diuji. Benih ini biasanya dihasilkan dengan
mengencerkan lumpur aktif dengan aquades.
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
5/11
The BOD test is carried out by : mengencerkan sampel dengan aquades jenuh
oksigen
menyuntik dengan sejumlah tetap benih,
mengukur oksigen terlarut (DO) dan kemudianmenyegel sampel untuk mencegah oksigenlarut dalam air lebih lanjut.
Sampel disimpan pada 20 C dalam gelap
untuk mencegah fotosintesis (danpenambahan oksigen) selama 5 hari, danoksigen terlarut diukur lagi.
Hal ini disebut sebagai BOD520
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
6/11
DO
The difference between the final DO and initial DO isthe BOD.
BOD can be calculated by: Undiluted BOD = Initial DO Final DO
Diluted BOD =
((Initial DO Final DO) BOD of seed) x dilution factor
BOD is equal to oxygen dissolved
The high BOD :DO consumed by bacteria for organic material breakingdown is also high that make other biotas can not life oran anaerobic condition is formed
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
7/11
BOD test condition
The rate of biological reaction is determined by : A number of bacteria
The number of bacteria has to be adequate
as neededneeds to be added from soil.
Nutrients
N, P, and trace elements have to be available
adequately
Temperature. Temperature has to be kept constant at 20oC
during the test, that similar to nature condition
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
8/11
Nitrification and oxidation of the nitrite
Caused by heterotro ph ic bacter ia when theincubat ion m ore than 5 days
2 NH3+ 3O22NO2- + 2 H+ + 2H2O
2NO2-+ 2 H+ + O22NO3
- + 2 H+
Oxidation inhibitor : 2-chloro-6 (trichloro
methyl)pyridine (TCMP)
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
9/11
Some chemicals in the water are toxic for thebacteria, including :
Phenol
Cr(VI) ion
Time (d)
BOD
(mg/L)
+ 6 mg/L Cr(VI) ion
+ 1 mg/LCr(VI) ion
+ 0 mg/LCr(VI) ion
Time (d)
BOD(mg/L)
5 5
+ 0 mg/L phenol
+ 5 mg/L phenol
+ 50 mg/L phenol
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
10/11
Measurement of DO
Volumetric with Winkler method Electrometric using DO meter
-
8/13/2019 BOD (Biochemical Oxygen Demand) ANALYSIS
11/11
BOD versus COD BOD is similar in function to chemical oxygen
demand(COD), in that both measure the
amount of organic compoundsin water.
However, COD is less specific, since itmeasures everything that can be chemically
oxidized, rather than just levels of biologically
active organic matter.
http://en.wikipedia.org/wiki/Chemical_oxygen_demandhttp://en.wikipedia.org/wiki/Chemical_oxygen_demandhttp://en.wikipedia.org/wiki/Organic_compoundhttp://en.wikipedia.org/wiki/Organic_compoundhttp://en.wikipedia.org/wiki/Chemical_oxygen_demandhttp://en.wikipedia.org/wiki/Chemical_oxygen_demand