A study has been carried out on aerobic biological treatment of a bulk drug industrial effluent which is highly acidic in nature and shows high value of BOD5 (≈ 36000 mg/l), COD (≈ 84000 mg/l). Chemical treatment conducted for neutralizing the pH followed by biological treatment using a lab-scale reactor with acclimatized bacterial consortia isolated from natural soil has confirmed its feasibility for biological treatment. About 99% removal of COD from starting value of around 8000 mg/l has been achieved. The COD value in different hydraulic retention time (HRT) has been brought down to less than 100 mg/l in treated effluent, showing high removal of dissolved organics by aerobic biological treatment.

1. Journal for Research| Volume 02| Issue 10 | December 2016
ISSN: 2395-7549
All rights reserved by www.journalforresearch.org 24
Feasibility Study of Treatment of Effluent from a
Bulk Drug Manufacturing Industry using Aerobic
Biological Treatment
Mriganka Sekhar Mukhopadhyay Dr. Vijay K. Dwivedi
Ph.D. Student Professor
Department of Civil Engineering Department of Civil Engineering
National Institute of Technology, Durgapur - 713209, India National Institute of Technology, Durgapur -713209, India
Dr. Soumya Bhattacharyya Dr. Sudit S. Mukhopadhyay
Professor Associate Professor
Department of Civil Engineering Department of Bio Technology
National Institute of Technology, Durgapur -713209, India National Institute of Technology, Durgapur -713209, India
Abstract
A study has been carried out on aerobic biological treatment of a bulk drug industrial effluent which is highly acidic in nature
and shows high value of BOD5 (≈ 36000 mg/l), COD (≈ 84000 mg/l). Chemical treatment conducted for neutralizing the pH
followed by biological treatment using a lab-scale reactor with acclimatized bacterial consortia isolated from natural soil has
confirmed its feasibility for biological treatment. About 99% removal of COD from starting value of around 8000 mg/l has been
achieved. The COD value in different hydraulic retention time (HRT) has been brought down to less than 100 mg/l in treated
effluent, showing high removal of dissolved organics by aerobic biological treatment.
Keywords: Aerobic Biological Treatment, Bio-kinetic Constants, Bulk Drug Effluent, COD
_______________________________________________________________________________________________________
I. INTRODUCTION
The modus operandi of a pharmaceutical industry has three main stages: (1) research and development; (2) conversion of organic
and natural substances into bulk pharmaceutical substances or ingredients through fermentation, extraction, and/or chemical
synthesis; and (3) formulation and assembly of the final pharmaceutical product. Chemical synthesis forms the basic process for
preparing the compounds that are used today as pharmaceutical products [17].
The manufacture of Bulk Drug through chemical synthesis mainly involves a complex series of batch processes where many
intermediate stages are present and many sequential chemical reactions take place. The processes use various raw materials and
generate wastes and emissions [2, 3], including the wastewater. The wastewater is high in biochemical oxygen demand (BOD),
chemical oxygen demand (COD) and total suspended solids (TSS), with a wide range of pH from 1 to 11 [16,8]. To keep the
environment and ecology unaffected, the generated waste should be treated before disposal to the environment and the rate of
generation of waste should also be minimized.
Several processes have been proposed for the treatment of the pharmaceutical effluents which include physical, chemical and
biological treatment [2, 5, 6, 16]. Biological treatment is a natural process and it plays a significant role in degradation of the
organic compounds [4, 11]. Both the aerobic and anaerobic biological systems have been studied for the treatment of
pharmaceutical effluents [9, 11, 17]. Installation cost of anaerobic system is very high which can hardly be afforded by small
bulk drug producing industries [6, 9]. On the other hand, aerobic treatment is a conventional process having low installation cost
and efficient for treatment of various types of pharmaceutical wastewaters [4].
This feasibility study for treatment has been carried out to develop a very simple wastewater treatment process which can be
afforded by the small bulk drug producing industries [12]. This will also involve evaluation of bio-kinetic constants for
understanding their potentialities in degrading the pharmaceutical effluents emanated specifically from the small bulk drug
industries [1, 10, 15].
II. MATERIALS AND METHODS
Materials
All the chemicals used in this study are either AR grade or Molecular Biology grade. Double distilled water has been used for
routine chemical analysis.

2. Feasibility Study of Treatment of Effluent from a Bulk Drug Manufacturing Industry using Aerobic Biological Treatment
(J4R/ Volume 02 / Issue 10 / 005)
All rights reserved by www.journalforresearch.org 25
Source and Characterization of wastewater
The wastewater for the present study has been collected from the equalization tank of a small bulk drug producing industry. The
Industry (situated at Behala, Kolkata) manufactures CALCIUM D-SACCHARATE USP (Calcium Glucarate) from dextrose to
fulfill export and domestic requirement. During the production of CALCIUM D-SACCHARATE USP some waste is generated.
The waste is mainly OXALIC ACID and un-reacted Dextrose. The sample was characterized using standard methods [13].
Chemical Treatment of Effluent Sample Collected from the Industry
Effluent sample has been treated chemically by Lime [Ca(OH)2] for neutralization [11]. Several trial experiments have been run
with different strength of Ca(OH)2.
Biological Treatment of Chemically Treated Effluent Sample
Seed Preparation and Acclimatization
The seed sample prepared from soil was taken in a 2000 ml measuring cylinder, where sugar, starch and peptone solution was
added as feed to bacterial mass to initiate bacterial growth and afterwards the acclimatization of the microorganisms in presence
of effluent sample was achieved by gradually increasing the dose of industrial effluent [5, 7, 14].
Reactor
Aerobic oxidation was performed in the laboratory in a 2-litre measuring cylinder made of glass (Photo 1). The reactor was
equipped externally with an air flow pump. It is also effective for uniform mixing [11].
Fig. 1: Reactor
Bacterial Degradation
Experimental runs were conducted with the chemically treated effluent sample collected from the industry. Continuous aeration
was done in the reactor.
III. RESULTS AND DISCUSSIONS
The results of analysis of (i) raw, (ii) chemically treated and (iii) diluted effluent sample are given in Table – 1.

3. Feasibility Study of Treatment of Effluent from a Bulk Drug Manufacturing Industry using Aerobic Biological Treatment
(J4R/ Volume 02 / Issue 10 / 005)
All rights reserved by www.journalforresearch.org 26
Table - 1
Results of Analysis of Effluent Sample of the Bulk Drug Industry
Parameters Raw Effluent sample Chemically Treated Sample Four times diluted Chemically Treated Sample
COD mg/lit 84692 32400 8100
BOD5 mg/lit 35982 14914 5671
pH 4.2 7.1 7.1
It is observed from the Table-1 that pH value of the sample is too low, which indicates that the sample is highly acidic in
nature. Simultaneously, it is observed that BOD and COD values are quite high. This sample is not suitable for biological
treatment because of the acidic characteristic of the waste and the wastewater sample being high in organic content. For this
reason the sample of wastewater is first neutralized by chemical treatment before subjecting it to biological treatment. It is
obvious that by chemical treatment with some alkali material, pH will increase and become suitable for biodegradation and the
organic content will also be reduced to a great extent.
It has been found that after the neutralization of the acidic sample by calcium hydroxide, the sample still contains quite a good
amount of COD value of the neutralized sample. The reduction in the COD value due to neutralization by calcium hydroxide is
about 62% (Table-1). The effluent sample after being treated chemically by Ca(OH)2 is diluted four times to obtain the low COD
value before being subjected to biological treatment. The reduced COD value of sample after dilution is given in Table-1.
As the chemically treated and diluted sample by nature is near to neutral, and it is suitable for biological treatment.
The treatments of pharmaceutical wastewater were conducted during 7th
March 2014 to 11th
March 2014. During this study
many parameters were analyzed for the characterization of raw wastewater and effluent after treatment. The results of
biodegradation study are shown in Table-2.
Table - 2
The Results of Biodegradation Study
Parameters Pretreated and Diluted Wastewater Effluent after Bio-Degradation
pH 7.1 7.3
COD mg/lit 8100 100
BOD5 mg/lit 5671 20
The experimental results show the initial COD and BOD5 concentration to be 8100 mg/l and 5670 mg/l respectively. The
concentration of COD and BOD5 of effluent after biological treatment are found to be 100 and 20 mg/l respectively confirming
the high efficiency of bacterial removal of organic content from the wastewater.
Evaluation of Biokinetic Constants
With starting BOD5 concentration of 5670 mg/l, the BOD5 values at varying θc were considered for the evaluation of Biokinetic
constants by using the following modified Monod’s equations.
= (1)
(2)
(3)
Where Ks = half-velocity constant mg/l, Y = yield coefficient, K = rate of substrate utilization per day, Kd = decay coefficient
per day, μmax = maximum specific growth rate, θc = mean cell residence time, U = specific utilization rate, mg BOD applied / mg
MLVSS / day. The values of S0 −S, Xθ, Xθ / (S0 −S), (S0 −S)/Xθ, 1/S, 1/θc were determined for the evaluation of biokinetic
constants on BOD basis. In order to evaluate these constants a graphical method was adopted and the method of least squares
was used to obtain the line of best fit. Considering the Monod equation Xθc / (S0 − S) = (Ks/K) (1/S) + (1/K), the term Xθ/ (S0 −
S), which is reciprocal of F/M ratio, was plotted against effluent substrate concentration 1/S and a straight line of best fit was
obtained on BOD basis. The ‘y’ intercept of the plot equals 1/K whose reciprocal gives the value of K. The slope of the plot is
equal to Ks/K. By multiplying slope of K the value of Ks was obtained. The BOD based values for Ks, K, Kd and Y were
116.61mg/l, 2.41d-1
, 0.038 d-1
and 0.31, respectively.
Table - 3
Bio-kinetic Constants Evaluated
Period of Experiment Temperature range Ks mg/lit K d-1
Kd d-1
Y
7th
March 2014 to 11th
March 2014 300
C 116.61 2.41 0.038 0.31
Temporal Variation of Percent COD Reduction and MLVSS Concentration, Interrelationship between Percent Increases
in MLVSS Concentration vs. Percent COD Reduction during the Biodegradation Study
Temporal variation of percent COD Reduction is graphically presented in Fig.-1. Temporal variation of MLVSS concentration is
graphically presented in Fig.-2. Interrelationship between percent increase in MLVSS concentration and percent COD reduction
is graphically presented in Fig.-3

4. Feasibility Study of Treatment of Effluent from a Bulk Drug Manufacturing Industry using Aerobic Biological Treatment
(J4R/ Volume 02 / Issue 10 / 005)
All rights reserved by www.journalforresearch.org 27
Fig. 2: Percent COD Reduction vs Time Curve
Fig. 2 shows the percent COD reduction with time during biodegradation of organic constituents present in the effluent from
the industry. The temperature in the reactor during biodegradation has been maintained at 300
C ± 20
C. It is observed that the
percent COD reduction increases with time and reaches the value of 99% after 4 days. From this graph it is clearly noted that
reduction rate of COD are not constant and it may vary from time to time. From day 1 to day 3 the COD reduction rate is very
high, Whereas for next two days the rates decline as is evident from the blue lines. On the fourth day the rate is slower than that
of third day and the same for the fifth day is further slower than that of fourth day. The percent COD reduction by bacterial
degradation gradually decreases with time as bacteria present in the system acts at faster rate initially but after some time its
activity reduces, because of the insufficiency in substrate concentration.
Fig. 3: MLVSS Concentration vs. Time
Fig - 3 shows the variation of MLVSS concentration with time curve biodegradation program at constant temperature (300
C).
The graph shows that MLVSS concentration increases with time and reaches 2135.9mg/lit after 4 days. From this graph it is
clearly noted that growth rates of bacteria are not constant but vary from time to time. The nature of curve suggests that the
microorganism has taken some time to acclimatize and the growth rate is slow during the first two days. After that the growth
rate becomes high (when F/M attains an optimum value) on the subsequent day (3rd
day). On 4th
day the rate again decreases
because of low COD value.
Fig. 4: Percent Increase of MLVSS vs. Percent COD Reduction

5. Feasibility Study of Treatment of Effluent from a Bulk Drug Manufacturing Industry using Aerobic Biological Treatment
(J4R/ Volume 02 / Issue 10 / 005)
All rights reserved by www.journalforresearch.org 28
Fig.-4 shows the variation of percent MLVSS concentration with percent COD reduction for biodegradation program at
constant temperature (300
C) for the effluent from the industry. The graph shows that there is a linear relationship with high
correlation (R2
value of 0.9999) between percent increase in MLVSS concentration and percent COD reduction in the present
experiment.
IV. CONCLUSIONS
Based on the findings of the physicochemical and biological treatment of effluent from Bulk Drug industry, the following
conclusions may be drawn:
 The results obtained from the investigation revealed the biodegradability potential of the effluent from Bulk Drug Industry
using mixed microorganisms to be cost-effective, as it takes less time for biodegradation of wastewater of bulk drug
manufacturing industries.
 The reactor study performed for the industrial effluent shows that it can be successfully treated biologically without any
inhibitory effect on bacterial growth.
 The high BOD5 and COD values are reduced by 99% by enriched microbial culture in aerobic system. It is possible to
remove COD even up to 99.88% if temperature is maintained between 280
C to320C which is conducive for bacterial
growth.
REFERENCES
[1] Benefield, L. D., Randall, C. W., Biological process design for wastewater treatment, Prentice-Hall, Inc., Eaglewood Cliffs, N.J. 1980.
[2] El-Gohary, F. A., Abou-Elela, S. I., Aly, H. I., “Evaluation of biological technologies for wastewater treatment in the pharmaceutical industry”. Journal of
Water Science & Technology, Volume 32, pp. 13-20. 1995.
[3] Freitas Dos Santos, L. M., G., Biundo Lo, G., “Treatment of Pharmaceutical Industry Process Wastewater using The Extractive Membrane Bioreactor”.
Journal of Environmental Progress & Sustainable Energy, Volume 18, Issue 1, pp. 34-39. 1999.
[4] Gilbert, M, Masters. Introduction to Environmental Engineering and Science, Second ed, Prentice-Hall, New Delhi. 2004.
[5] Kabdasli, I., Gurel, M., Tunay, O., “Pollution Prevention And Waste Treatment In Chemical Synthesis Processes For Pharmaceutical Industry”, Journal of
Water Science and Technology, Volume 39, Issue 10, pp. 265-271. 1999.
[6] Mayabhate, S. P., Gupta, S. K., Joshi, S. G., “Biological Treatment of Pharmaceutical Wastewater”, Journal of Water Air and Soil Pollution, Volume 38,
pp. 189-197. 1988.
[7] Metcalf, Eddy, Wastewater Engineering, Third ed, Tata McGraw-Hill, New Delhi. 1991.
[8] Mukhopadhyay, M. S., Bhattacharyya, S., Dwivedi, V. K., “ An Overview on Treatment of Waste Water from Bulk Drug Industries”, Journal of Institution
of Public Health Engineers, India, Volume 2013-14, Number – 2, 27–29. 2013.
[9] Rao, G. A., Naidu V. G., Prasad, K., Rao, C. N. K., “Anaerobic Treatment of Wastewater with High Suspended Solids from a Bulk Drug Industry Using
Fixed Film Reactor (AFFR)”, Journal of Bioresource Technology, Volume 96, pp. 87–93. 2005.
[10] Rebhun, M., Galil, N., Narkins, N., “Kinetic studies of chemical and biological studies treatment for renovation”, Journal of Water Pollution Control
Federation, Volume 57, pp. 324–331. 1985.
[11] Samuel, D., Suman, R., Anjaneyulu, Y., “Evaluation of Biokinetic Parameters for Pharmaceutical Wastewaters using Aerobic Oxidation Integrated with
Chemical Treatment”, Journal of Process Biochemistry, Volume 40, pp. 165–175. 2005.
[12] Sincero, P. A., Sincero, C. A., Environmental engineering—a design approach, Prentice-Hall, India.1996 Standard Methods for the Examination of Water
and Wastewater: 1975, 21st ed., APHA, Washington, D.C. Vaidyanathan, R. T., Meenabal, T., Eenthilvelan, K., Vijaykumar, T., “Treatability of
predigested distillery wastewater diluted with domestic sewage”, Indian journal of Environment Protection, Volume 15, Issue 4, pp. 241–243. 1995.
[13] Vasicek, P. R., “Use of Kinetic Study to Optimize the Activated Sludge Process”, Journal of Water Pollution Control Federation, Volume 54, pp. 1176–
1184. 1982.
[14] William, B. J., Bhat, J. V., “Microbial Metabolism of Oxalic Acid”, Journal of American Society for Microbiology, Volume 22, pp. 75-80. 1958.
[15] Yalcin, A. O., Orhan, I., Sallis, P., Donnelly, T., Bahar K. I., “Anaerobic Treatment of a Chemical Synthesis-Based Pharmaceutical Wastewater in a Hybrid
Upflow Anaerobic Sludge Blanket Reactor”, Journal of Bioresource Technology, Volume 99, pp. 1089–1096. 2007.