TRIBHUWAN UNIVERSITY
INSTITUTE OF ENGINEERING
PULCHOWK CAMPUS
A Proposal On
Kinetics of Manganese removal using different proportion
of BIRM and Katalox
By:
Kishor Nepal
075MSEnE011
DEPARTMENT OF
ENVIRONMENTAL ENGINEERING
INSTITUTE OF RNGINEERING
February, 2021
I
ACKNOWLEDGEMENT
I would like to thank to our Coordinator of Environmental Engineering, Asso. Prof.
Iswar Man Amatya for giving us the opportunity to explore different ideas in the field
of environmental engineering for the preparation of this thesis.
I would also like to thank my Asso. Prof. Mr. Ram Kumar Shrestha for helping me
enhances my knowledge regarding the topic and sharing with me the different insights
he found out during his research.
Finally, I would like to thank all our teachers and friends who have helped me directly
or indirectly for deciding me with this project topic and research decision.
Kishor Nepal
075MSEnE011
II
Contents
ACKNOWLEDGEMENT...................................................................................................2
List of table..........................................................................................................................4
List of figure........................................................................................................................4
1 BACKGROUND..............................................................................................................1
2 STATEMENT OF PROBLEM.........................................................................................2
3 RATIONALE OF THE STUDY......................................................................................2
4 OBJECTIVES...................................................................................................................3
4.1 Main Objective...........................................................................................................3
4.2 Specific Objectives.....................................................................................................3
5 LIMITATIONS OF THE STUDY...................................................................................3
6 INTRODUCTION............................................................................................................3
7 LITERATURE REVIEW.................................................................................................4
7.1 Sources of Manganese in water and its effects...........................................................4
7.2 Maganaese Removal Processes..................................................................................5
7.3 Oxidation Followed by Filtration...............................................................................6
7.4 Simple Aeration using gravity aerator (Bucket Type)...............................................7
7.5 Manganese Greensand Filter......................................................................................7
8 RESEARCH METHODOLOGY.....................................................................................8
8.1 Modelling and Sampling............................................................................................8
8.2 Experimental Setup and Experimental parameters....................................................8
9 HYPOTHESIS OF THE STUDY.....................................................................................9
10 WORK SCHEDULE....................................................................................................10
11 BUDGETING...............................................................................................................10
REFERENCES..................................................................................................................11
A Manganese Analysis by UV Spectrophotometric Method.........................................13
B. Iron Analysis by Phenanthrozine Spectrophometric.................................................13
C. Total Hardness by EDTA Titrimetric Method...........................................................13
D. Alkalinity by Titration Method.................................................................................14
III
ANNEX-2: Site Investigation Photos................................................................................15
Y
List of table
Table 1. Detail of model....................................................................................................13
Table 2: Experimental Parameters and Method applied....................................................13
Table 3. Total expected budget..........................................................................................14
List of figure
YFigure 1. Flow diagram showing the process of Manganese removal................................
Figure 2. Diagram of greensand filter................................................................................12
IV
V
1 BACKGROUND
Kathmandu, the capital of Nepal, lies in the Kathmandu Valley which occupies almost
a circular area of 656 km2 with north-south and east-west axes both of approximately
30km. Central flat land in the Valley is of around 400 km2 with elevation of 1,300 m
to 1,400 m, surrounded by the mountainous region of elevation over 2,000 m.
Kathmandu forms an urban area in the Valley, unified with the neighboring Lalitpur,
Madhyapur and Bhaktapur, showing recently population expansion as well as the
industrial intensification as a political and economic Centre of the nation. In response
to the request of peoples of Manohara besi, Changunarayan Municipality, Duwakot,
Bhaktapur, the Rural Water Supply and Sanitation Fund Development
Board(RWSSFDB) sent the Preliminary Study Team to the Manoharabesi site from
B.S 2073. Concluded in the Preliminary Study were: Manoharabesi Projects both will
have a high feasibility in their implementation and completed the on last bhadra B.S
of 2077. The Planned Service Area (Target Area) of the Project are around the
Manohara besi, Changunarayan Municipality, Duwakot, Bhaktapur and the planned
intake amount is 410.4 cubic metre per day through the deep boring using 7.5hp
motor. However, the suitability of groundwater for drinking purpose is questionable.
The extensive use of groundwater along with the improper management of solid waste
and wastewater has caused the quality degradation and source depletion. A study
conducted by Khatiwada et al., showed excessive concentration of nitrate, iron,
manganese and ammonia, above the WHO standard. Manganese occurs naturally in
many surface water and groundwater sources and in soils that may erode into these
waters. However, human activities are also responsible for much of the manganese
contamination in water in some areas. At concentrations as low as 0.02
mg/l, manganese can form coatings on water pipes that may later slough off as a black
precipitate (Bean, 1974). A number of countries have set standards for manganese of
0.05 mg/l, above which problems with discoloration may occur.
1
2 STATEMENT OF PROBLEM
However, on a chronic basis, manganese has the potential to cause mainly in the
respiratory tract and the brains. Nepal’s Drinking Water Quality Standard(NDWQS)
and WHO recommends guideline value of 0.01mg/l for Mn. Manganese compounds
exists naturally in the environment as solids, small particle in the water and dust as in
air particles. Methods to control manganese in distribution systems include arranging
for alternate water sources, adding phosphate to the water to keep iron and manganese
in solution, and oxidizing and removing by filtration among them oxidizing and
removing by filtration is cast effectiveness. Oxidation of manganese with air is by far
the most cost-effective method since there is no chemical cost; however, there are
disadvantages. The oxidation process can be slowed and the reaction tank has to be
quite large (if there are high levels of manganese). In addition, small changes in water
quality may affect the pH of the water and the oxidation rate may slow to a point
where the plant capacity for manganese removal is reduced. Practically, the
concentration of manganese is determined by spectrophotometry.
3 RATIONALE OF THE STUDY
Water source in the Manoharabesi Water Supply and Sanitation Scheme is deep
boring water. A raw water sample from deep well results the ambient Manganese
concentration. Manganese deposits are also known to cause problems in drinking
water systems, stemming from increased tuberculation in pipes and coating
development in concrete tanks. Manganese can deposit on other surfaces such as filter
media. In the distribution system, Mn deposits can be formed by either chemical or
microbial oxidation, depending on numerous water quality parameters. These
particles can impact a dark color to the water and may lead to noticeable amounts of
discrete particles in delivered water. This process can occur when soluble Mn
concentrations are greater than 0.02 mg/L. A finished water Mn concentration below
0.02 mg/L is a common treatment goal for preventing chronic aesthetic and
operational problems associated with manganese. Manganese concentrations in
drinking-water are easily lowered using common treatment methods. Oxidation and
2
filtration are usually adequate to achieve a manganese concentration of 0.05 mg/l in
drinking-water.
3
4 OBJECTIVES
4.1 Main Objective
The main objective of this proposal is to determine the effective proportion of Katalox
and Birm for removal of manganese.
4.2 Specific Objectives
To evaluate the Mn removal efficiency in water treatment processes.
To investigate the filter media depth of Katalox and Birm.
To determine the filter head loss for different proportion of media.
5 LIMITATIONS OF THE STUDY
The limitations of the study are as mentioned below:
The manganese contaminated water to be used is natural ground water, not
synthetic. Thus, other factors like pH, turbidity may influence the result,
which are not taken into consideration.
Bacterial Growth rate will not be considered.
Effect of temperature is not considered.
4
6 INTRODUCTION
Mn is an abundant transition metal of the earth's crust, of which it comprises
approximately 0.1%. This mineral is primarily associated with aesthetic problems,
such as the discoloration of water, unpleasant taste of water, and staining of plumbing
fixtures and laundry; however, the presence of Mn in tap water is not known to cause
health problems. The presence of discolored drinking water due to Mn can mitigate
customer confidence. At the same time, deposited insoluble Mn in water transmission
pipes can cause increased turbidity, and reduced flow. Mn can have various colors,
depending on its oxidation state. Mn4+ is insoluble, and has a brown-black color;
while Mn2+ is soluble, and has a pale pink color. Aqueous Mn2+ is the dominant
form of Mn in anoxic waters. It can be found by the reduction that takes place in the
presence of metal-reducing bacteria under anaerobic or low oxidation conditions at
the sediment/water interface.
Oxidation of Mn2+ can thermodynamically lead to three different insoluble MnOx(s)
(e.g., MnO2, Mn2O3, and Mn3O4) with the predominant form being MnO2. The
predominant form of Mn in surface water is soluble Mn+2, while insoluble Mn+3 and
Mn+4 also exist. Insoluble Mn can be relatively easily removed at the conventional
water treatment processes composed of coagulation, sedimentation and granular
media filtration, while soluble Mn is hardly removed. Therefore additional treatment
and/or processes are needed to remove soluble Mn at M WTPs.
5
7 LITERATURE REVIEW
7.1 Sources of Manganese in water and its effects
Mn occurs naturally in many surface water and groundwater sources and in soils that
may erode into these waters. The Earth’s crust is a major source of Mn to the
atmosphere, soil and water. In surface waters, Mn occurs in both dissolved and
suspended forms, depending on factors such as pH, anions present and oxidation–
reduction potential. High concentrations may occur in polluted rivers or under low
oxygen conditions such as at the bottom of deep reservoirs or lakes, or in
groundwater. Concentrations of dissolved Mn in natural waters that are essentially
free of anthropogenic inputs can range from 0.01 to > 10 mg/L. Higher levels in
aerobic waters are usually associated with industrial pollution and the low oxygen
environments found in groundwater and some lakes and reservoirs favour high Mn
levels.2 In Australian drinking water supplies, Mn concentrations can range up to 1.41
mg/L, but are typically less than 0.01 mg/L. For example, the median Mn
concentration at a regional NSW treatment plant was 0.005 mg/L over a nine-year
period.
Mn is an essential element that is required by humans for normal growth. Mn
deficiency affects bone, the brain and reproduction. The greatest source of Mn is
usually from food and intake from drinking water is substantially lower. The health
effects from over exposure of Mn are dependent on the route of exposure, the
chemical form, the age at exposure, and an individual’s nutritional status. Toxicity has
occurred mainly as a result of inhalation of Mn dust over long periods in occupational
settings. The nervous system has been determined to be the primary target with
neurological effects generally observed. In contrast to inhalation exposure, Mn is
regarded as one of the least toxic elements via the oral route. In one case involving
heavy consumption of highly contaminated well water that contained Mn
concentrations > 14 mg/L the symptoms included lethargy, increased muscle tone,
tremor and mental disturbances, however, concentrations of other metals were also
high and the reported effects may not have been due solely to Mn. Evidence of
neurological, cognitive, and neuropsychological effects of Mn exposure from drinking
water in children has generated widespread public health concern.
6
7.2 Manganese Removal Processes
Manganese (Mn) removal in drinking water filters is facilitated by biological and
physico-chemical processes. This paper reviews various technologies that have been
used to treat manganese containing wastewater and ground water, such as chemical
precipitation, coagulation, flotation, ion-exchange, oxidation/filtration,
electrochemical treatment, adsorption, and membrane filtration. Recovery of
manganese is also very imperative due to its economical and environmental aspects.
However, there is limited information about the dominant processes for Mn removal
in full scale matured filters with different filter materials over filter depth. Control of
the concentration of Mn in potable water involves source water management as well
as treatment processes for removal of manganese from water. A recent guidance
manual for control of Mn provides a comprehensive overview including a number of
case studies. While not the focus of this review paper, it is important to note that
effective source water management can often be a significant Mn control strategy. For
groundwater supplies that include multiple wells, it may be possible to blend waters
with higher and very low Mn concentrations to achieve an acceptable net Mn level.
Removal of Mn from drinking water sources can be accomplished by a range of
different physical, chemical, and biological processes. Recent publications from the
Water Research Foundation and the American Water Works Association provide
useful guidance. A schematic overview of treatment options is shown in Fig. 1.
Characterization of the source water, including the concentration and form of
Mn, along with levels of other key parameters (e.g., pH, alkalinity, organic carbon,
iron, hardness, etc.), is a critical first step. Distinguishing between particulate and
dissolved forms of Mn is necessary in order to select appropriate treatment processes.
Traditional operational definitions of the dissolved fraction are often based on use of
laboratory membrane filters with pore sizes of 0.2 to 1 ×10−6m (or 0.2 to 1 micron).
However, it is useful, and sometimes necessary, to also separate the traditional so-
called dissolved fraction into colloidal and dissolved fractions by the use of an
ultrafiltration membrane of a specified molecular weight cutoff, e.g., a 30,000 or
10,000 Dalton ultra-filter. Colloidal or nanoparticle manganese is typically oxidized
and thus in particulate form. Including colloidal manganese in the dissolved fraction
can lead to in- appropriate dosing of oxidants or selection of an ineffective treatment
process. When combined levels of iron and manganese exceed 10 mg/L, the most
effective treatment involves oxidation followed by filtration. In this process, a
7
chemical is added to convert any dissolved iron and manganese into the solid,
oxidized forms that can then be easily filtered from the water.
Figure 1. Flow diagram showing the process of Manganese removal
7.3 Oxidation Followed by Filtration
When combined levels of iron and manganese exceed 10 mg/L, the most effective
treatment involves oxidation followed by filtration. In this process, a chemical is
added to convert any dissolved manganese into the solid, oxidized forms that can then
be easily filtered from the water. Chlorine is most commonly used as the oxidant
although potassium permanganate and hydrogen peroxide can also be used. A small
chemical feed pump is used to feed the chlorine (usually sodium hypochlorite)
solution into the water upstream from a mixing tank or coil of plastic pipe. The
mixing tank or pipe coil is necessary to provide contact time for the manganese
precipitates to form. It may be necessary to install an activated carbon filter to remove
the objectionable taste and odor from the residual chlorine. Chlorine is not
recommended as an oxidant for very high manganese levels because a very high pH is
necessary to completely oxidize the manganese. Significant system maintenance is
required with these units. Solution tanks must be routinely refilled and mechanical
filters need to be backwashed to remove accumulated manganese particles. If a carbon
filter is also installed, the carbon would need to be replaced occasionally as it
8
becomes exhausted. The frequency of maintenance is primarily determined by the
concentration of the metals in the raw water and the amount of water used.
9
8 RESEARCH METHODOLOGY
8.1 Modeling and Sampling
The research is to be carried out in a continuous down-flow reactor. The reactor is to
be filled with gravel as supporting media(25 inch), the depth of Katalox (75-120 Cm),
and Birm (40-75 Cm) is varies for three different combination to get the depth
equivalent to economical use of material corresponding to maximum removal of
manganese. The physical Characteristics of Birm and Katalox are shown in table 1
and table 2.
Table 1: Physical Properties of Katalox Light
Appearance Granular Black Beads
Odor None
Mesh Size 0.6-1.4 mm
Uniformity Coefficient ≤1.75
Bulk Density 1060 Kg/m3
Moisture Content <0.5% As Shipped
Filtration < 3 Micron
Loading Capacity 1500 mg/m3 for Mn2+ alone
Table 2: Physical Properties of BIRM
Appearance Black
Mesh Size 0.4-2.0 mm
Uniformity Coefficient 2.7
Bulk Density 720.8 Kg/m3
Effective Size 0.48 mm
Specific Gravity 2000 Kg/m3
8.2 Experimental Setup and Experimental parameters
Water sample from inlet and outlet is collected in the frequency of 5 days and tested
for targeted parameters. The parameters considered in the study, their measurement
methods to be used and the test frequency are shown in table 3. The measurements
will be done as per Standard Methods for the Examination of Water and Wastewater.
10
Figure 2 Diagram of greensand filter
The details of model is shown in Table 1
Table 1. Detail of model
i. Height (cm) 50
ii. Diameter (cm) 6
iii. Volume (cm3) 1414
iv. Porosity (%) 45
v. Depth of Anthracite(cm) 5
vi. Depth of Mn Greensand(cm) 15
vii. Depth of Gravel(cm) 7
viii. Coefficient of uniformity 1.6
9 HYPOTHESIS OF THE STUDY
11
10 WORK SCHEDULE
11 BUDGETING
12
REFERENCES
Amatya Iswar Man ,Kansakar Bhagwan Ratna, Tare Vinod, , Fiksdal Liv, impact of
temperature on biological denitrification process, Pulchowk Campus, Institute
of Engineering, Tribhuvan University.
ATSDR, Atlanta, (2008). Toxicological Profile for Manganese, In US
Department of Health and Human Services Ed. Agency for Toxic
Substances and Disease Registry.
Brandhuber P, Clark S, Knocke W, Tobiason J.( 2013). Guidance for the treatment of
manganese. Denver: Water Research Foundation.
Banta RG, Markesbery WR (1977) Elevated manganese levels associated with
dementia and extrapyramidal signs. Neurology, 27:213–216.
California Environmental Protection Agency.(2015).Drinking water notification
levels and responselevels: an overview. Sacramento: State Water Resources
Control Board, Division of Drinking Water.
Canavan MM, Cobb S, Srinker C (1934) Chronic manganese poisoning. Archives of
Neurology and Psychiatry, 32:501–512.
Davidsson L et al. (1989b) Manganese retention in man: A method for estimating
manganese absorption in man. American Journal of Clinical Nutrition,
49:170–179.
Hoyland VW, Knocke WR, Falkinham JO (2014), Pruden A Effect of drinking water
treatment process par biological removal of manganese from surface
Res.;66:31–9.
Khatiwada, N., Takizawa, S., Tran, T., & Inoue, M. (2002). Groundwater
contamination assessment for sustainable water supply in Kathmandu Valley,
Nepal. Water Science and Technology, 147-154.
Kohl PM, Medlar SJ. (2006). Occurrence of manganese in driand manganese control.
Denver: American Wi Association.
Riddick TM, (1958).Lindsay NL, Tomassi A. Iron and manganese in water supplies. J
Am Water Works Assoc,50(5):688–96.
13
US EPA. ,(2004).Drinking Water Health Advisory for Manganese, In US
Environmental Protection Agency, Office of Water: Washington.
Udmale, P., Ishidaira, H., Thapa, B. R., & Shakya, N. M. (2016). The Status of
Domestic Water Demand: Supply Deficit in the Kathmandu Valley, Nepal.
Water, 1-9.
WHO. (2011). Guidelines for Drinking-water Quality (4th ed.). Geneva: WHO.
Zapffe C. (1933).The history of manganese in water supplies a for its removal. J Am
Water Works Assoc.25(5).
14
ANNEX-1: Test Proceduress
A Manganese Analysis by UV Spectrophotometric Method
Manganese was tested using the UV spectrophotometer and a series of standard
solution of KMno4 was prepared from the standard concentration of 1000 mg/l from
lab with respective dilutions Procedure for preparation of reagents:
a. 100ml of raw water sample was taken.
b. 5ml of special reagent was taken.
c.1-2 drops of H2O2 was added and boiling was done to reduce the volume upto 10ml.
d.1gm of Ammonium per Sulphate was added and boiled upto 1minute.
e. The sample was cooled in the room temperature.
f. Calculation was done by plotting absorbance of standards against concentrations
and computing sample concentration from that curve at 525nm.
B. Iron Analysis by Phenanthrozine Spectrophometric
Iron was tested using the Phenanthrozine Spectrophometric spectrophotometer and a
series of standard solution of Iron was prepared from the standard concentration of
1000 mg/l from lab with respective dilutions.
Test procedure
a. 10ml sample I contains>200µg Iron
b. 2ml conc. Hcl and 1ml hydroxylamine solution was added.
c. Boiling was done and quantity was reduced to half.
d.The sample was cooled at room temperature and was transferred to volumetric flask.
e.10ml ammonium acetate buffer and 4 ml of phenanthrozine solution was added.and
the required quantity is adjusted to 50ml in volumetric flask.
Calculation was done by plotting absorbance of standards against I concentrations and
computing sample concentrations from that curve.
C. Total Hardness by EDTA Titrimetric Method
Procedures for preparation of reagents
15
a. Dissolve 16.9 g ammonium chloride (NH4Cl) in 143 ml conc ammonium hydroxide
(NH4OH). Add 1.25 g magnesium salt of EDTA (available commercially) and dilute
to 250 ml with distilled water.
Test Procedure
a. 2 drops of EBT is to be added to 50ml of the water sample.
b. The water sample is to be then titrated with standard EDTA titrant slowly, with
continuous stirring, until the last reddish tinge disappears and blue solution appears,
which the end point is.
Total Hardness as mg CaCO3/L = A*B*1000/mL sample
Where, A = mL titration for sample and
B = mg CaCO3 equivalent to 1mL EDTA titrant
D. Alkalinity by Titration Method
Procedure for preparation of reagent
a. Mixed bromocresol green-methyl red indicator is to be prepared by dissolving of
0.02 gm of methyl red and 0.1 gm of Bromocresol Green in 100 ml of 95 % ethanol.
b. Preparation of 95 % ethanol by dissolution of 95 ml of ethanol in 5 ml of water.
Test procedures
a. 10 ml of sample is to be taken in conical beaker and 1 drop of MR-BCG indicator
was added and stirred rapidly.
b. Titration is to be done with 0.02N H2SO4, noting the end point.
c. Calculation of Bicarbonate concentration by:
HCO3-(mg/l) = [a (ml)/V(ml)] x 0.02 (N) x 0.02 x F x 61(g/mol) x1000 (mg/g) Where,
a = ml 0.02 N H2SO4 used
V = ml of sample
F = Factor of 0.02N H2SO4
16
ANNEX-2: Site Investigation Photos
17
