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APPENDIX A

Brief Overview of Analytical Procedures for Estimation of Various Wastewater

Parameters

The procedures outlined in “Standard methods for the Estimation of Water and

Wastewater characteristics” APHA - 2005 has been used.

(a) pH

pH of all the wastewater samples collected were measured immediately within 10

minutes using a portable digital pH meter (Model pH-201, accuracy +/- 0.01)

consisting of a glass electrode and a digital display inbuilt in the instrument.

(b) Electrical Conductivity

Conductivity of a solution is a.measure of its ability to carry an electric current, and it varies with number and types of ions present in it. In very dilute solutions, conductivity is directly proportional to the amount of dissolved solids. In practice, measurement of conductivity consists of measuring the resistance of a column, of solution with reference to a standard temperature. Electrical conductivity is expressed as µS/cm. The electrical conductivity of wastewater samples in this study were measured in the laboratory using a digital conductivity meter (Model - D1 9001, accuracy of ± 1µS / cm).

(c) Chloride Chloride (Cl-) ion is one of the major inorganic anions generally present in wastewater. It is estimated by means of a 'volumetric procedure' using silver nitrate as the 'titrant' and potassium chromate as the 'indicator'. The 'end point' is the appearance of a reddish tint precipitate. The corresponding end point burette reading (V1ml) is noted. The chloride (Cl-) concentration is then estimated using the equation ( A.1 )

Chloride concentration (mg/L) =

(ml) sample of volumeStandard100035.45nitratesilver ofMolarity )VV( 21 - A.1)

where, V1 - Burette reading corresponding to the 'end point' of sample (ml) and

196

V2 - Burette reading corresponding to the 'end point' of blank (Distilled water) (mL)

(d) Sulphate Sulphate in the sample is precipitated as barium sulphate in a medium containing hydrochloric acid (HCl) and barium chloride. The precipitate appears as a white turbid solution whose absorbance is measured using UV - Visible Spectrophotometer (Model: UV - 160 A; Shimanzu, Japan). The concentration of sulphate present in the sample was then obtained from the standard calibration graph obtained using known concentrations of sulphate.

(e) Total Solids (TS) and Total dissolved solids (TDS)

A well mixed sample was evaporated in a weighing dish and dried to a constant weight

in an oven to 103°C to 105°C and the TS of the sample is obtained using

TS (mg/L) = (w2-w1)/ Volume of sample .. (A.2)

where, w1 = empty weight of crucible; w2 = (weight of crucible + residue).

For determining TDS, remains of the sample was filtered through a glass fibre filter

(1μm, Whatman GF) and subjected to evaporation at 103°C - 105°C, for one hour. The

TDS is then obtained using

TDS (mg/L) = (w2-w1) / Volume of sample .. (A.3)

where, w1 = empty weight of crucible; w2 = (weight of crucible + filtrate residue).

(f) Chemical Oxygen Demand (COD)

COD represents the amount of oxygen required to oxidize all organic compounds

(both biodegradable and non-biodegradable) present in the wastewater to CO2 and

water. COD determination requires about 2 to 3 hours for digesting the organic

compounds in the presence of strong oxidizing agents using COD reflux apparatus.

The best suited oxidizing agent is K2Cr2O7. After cooling the refluxed sample to room

temperature, the excess dichromate was titrated with ferrous ammonium sulphate

(FAS). The amount of oxidisable organic matter measured as oxygen equivalent, is

then taken as COD and it is calculated as follows:

COD (mg/L) = [(A-B) molarity of FAS 8000 / (Volume of sample)] .. (A.4)

where, A = titrant value of blank solution; B = titrant value of the sample.

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APPENDIX B

Maximum Permissible Limits for Industrial Effluent Discharges (in mg/L)

Parameter Into inland surface waters IS: 2490 (1974)

Into public sewers IS: 3306 (1974)

On land for irrigation

IS: 3307 (1974 pH 5.50-9.0 5.50-9.00 5.50-9.00 Biological oxygen demand (for 5 days at 20°C)

30.00 350.00 100.00

Suspended solids 100.00 600.00 200.00 Total dissolved solids (inorganic)

2100.00 2100.00 2100.00

Temperature (°C) 40.00 45.00 - Oil and grease 10.00 20.00 10.00 Phenolic compounds 1.00 5.00 - Cyanides 0.20 2.00 0.20 Sulphides 2.00 - - Fluorides 2.00 15.00 - Total residual chlorine 1.00 - - Pesticides - - - Arsenic 0.20 0.20 0.20 Cadmium 2.00 1.00 - Chromium (hexavalent) 0.10 2.00 - Copper 3.00 3.00 - Lead 0.10 1.00 - Mercury 0.01 0.01 - Nickel 3.00 3.00 - Zinc 5.00 15.00 - Chlorides 1000.00 1000.00 1000.00 Boron 2.00 2.00 2.00 Sulphates 1000.00 1000.00 1000.00 Sodium (%) - 60.00 60.00 Ammonocal nitrogen 50.00 50.00 - Radioactive materials - - - Alpha emitters (milli curie/milliliter)

10-7 10-7 10-8

Beta emitters (as curie/milliliter)

10-6 10-6 10-7

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APPENDIX C

ANALYSIS OF SOIL SAMPLES (A) Geotechnical Characteristics Generally, tests are conducted on soils to determine their index properties, strength

and deformation characteristics. However, as the primary process of the present study

is to understand the basic behaviour of soils when they are artificially contaminated

with industrial wastewaters, only index properties and salient strength characteristics

were evaluated for the two soils, before and after they were artificially contaminated

with the two wastewaters considered in this study. Accordingly, following tests were

conducted on the two soils for characterizing them and for understanding their

behaviour after artificially contaminating them with industrial wastewaters.

(1) Visual observations Visual observations are generally employed in place of precise laboratory tests to

define the basic soil properties.

(2) Specific Gravity Indian Standard recognizes two methods for determining the specific gravity of soils,

which plays an important role in the computation of other soil properties, like void

ratio, unit weight and in other important Geotechnical Engineering - related

calculations. Pyrometer test is adopted as a laboratory methods for fine grained soils,

whereas, gas jar method is adopted as a field method for fine, medium and coarse

grained soils. As all the soil samples selected for this study were predominantly fine-

grained and as the above property was determined m the laboratory, pycnometer test

was selected and adopted for determining the specific gravity of all soil samples,

following the standard procedure outlined in IS:2720 (Part 3/Settion 1) - 1980

(reaffirmed: 1987).

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(3) Grain Size Analysis Grain size analysis expresses quantitatively the proportions by mass of the various

sizes of particles present in any soil sample. Wet sieving for all soils and dry sieving

for soils which do not have appreciable amount of clay, both for particles larger than

75 - microns and pipette/ hydrometer method (for particles lesser than 75- microns)

are recommended in IS:2720 (Pant 4) - 1985. Sedimentation method or hydrometer

method was used as the soil samples are expected to contain substantial quantities of

fine grains, especially, lesser than 75- microns. All the methods following were as per

IS:2720 (Part -4) 1985. The results of grain size analysis can be widely used in soil

classification and various design purposes. In this study, it will be useful primarily in

soil classification and in quantitatively evaluating the fine-grained fractions, for better

understanding of the physico-chemical process and the effect of effluents.

(4) Atterbtiys Limits

Consistency is a term used to indicate the degree of firmness of cohesive soils. As

water content alone is not an adequate index of consistency for engineering and many

other purposes, consistency of a soil can be expressed in terms of: (i) Atterberg limits

of soils and (ii) Unconfined compressive strength of soils. If the water content of a

thick suspension of clay is gradually reduced, the clay - water mixture undergoes

changes from liquid state through a plastic state and finally into a solid state. The

water content corresponding to the transition from one state to another is termed as

'Atterberg limits' and they are: liquid limit (wi), plastic (wp), limit and shrinkage limit

(ws).

Liquid and plastic limits of soils are both dependent on the amount and type of clay

in a soil and they form the basis for soil classification system for cohesive soils,

besides relating to various other properties of the soil. IS:2720 (Part 5)-1985 lays

down three methods of test for the determination of liquid limit and plastic limit of

soils. Three methods namely, (i) mechanical method; (ii) one point method and (iii)

cone penetration method, are recognized for the determination of liquid limit.

200

However, for the all national and international reports, either mechanical method or

cone penetration method alone is recommended. Hence, in this study, the

mechanical methods-the most popular method was selected and used for the

determination of liquid limit of all soil samples. Standard weight of soil sample

passing throughout 425 - micron IS sieve and mixed thoroughly with distilled water

was prepared and the standard procedure as stipulated in IS:2730 (Part 5) - 1985 was

followed to obtain a, 'flow curve' (a st. line) which was plotted on a semi-

logarithmic graph, representing 'water content' on 'linear/arithmetic scale' and the

number of drops' on the logarithmic scale. The moisture content corresponding to 25

drops as read from the above flow curve (rounded - off to the nearest whole number)

and reported as liquid limit of the soil. The above flow curve was extended (at either

end) so as to intersect the ordinate corresponding to 10 and 100 drops. The slope of

this line expressed as the difference in water contents at 10 drops and at 100 drops

and reported as the ‘flow index’.

Soil samples as for determining the liquid limit, can also be used for determining

plastic limit. A ball with about 8 grams of the above soil mass was formed and rolled

between the fingers and a glass paste with just sufficient pressure to roll the mass-soil

into a thread of uniform diameter The soil is then kneaded together to a uniform mass

and rolled again and this process (ie alternate rolling and kneading) is continued until

the thread crumbles under pressure required for rolling and the soil can no longer be

rolled into a thread. The moisture content of crumbled pieces of soil thread determined

by IS: 2720 (Part 2) - 1973 and reported as the 'plastic limit'.

IS 2720 (Part 6) - 1972 (reaffirmed l978)[ ] deals with the methods of test for determination

of shrinkage factors for soils, namely, shrinkage limit (remoulded soil), shrinkage

ratio, shrinkage index and volumetric shrinkage of soils. About l00 g of sample soil

from a thoroughly mixed portion of the material passing through 425 micron IS sieve

and which was obtained in accordance with IS:2720 (Part 1) - 1983 constitute the

sample for the determination of shrinkage limit (remoulded soil) and other allied-

properties of soil. Soil sample prepared as above and tested in accordance with the

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procedure in IS:2720 (Part 6) - 1972 and the data obtained there of, was used to

calculate the various shrinkage factors as using the formula listed below.

Shrinkage limit (remoulded soil) (ws) was obtained using Eqn. (C1)

100Wo

VoVWWs

…(C1)

where, ws - shrinkage limit in percent; w - moisture content of wet soil pat in percent;

V- volume of wet pat in ml; Vo - Volume of dry soil pat in ml and Wo = weight of

oven - dry soil pat in g.

Shrinkage ratio (R) is calculated using the following eqn. (C2)

R = VoWo …(C2)

Where,

Wo = weight of oven dry pat in g and

Vo = volume of oven dry soil pat in g.

Volume change or Volumetric shrinkage (Vs) is calculated using the following eqn.

(C3)

Vs = (W1 – Ws) R …(C3)

(5) Standard Proctor Test

IS: 2720 (Part 7) - 1980 (reaffirmed 1987), deals with the methods of test for the

determination of water content - dry density relations of soil using light compaction,

especially for cohesive soils. The above method is also referred to as 'standard proctor

(compaction) test'. In the above test a 2.6 kg rammer falling through a height of 310

mm was used. Air-dried soil material (about 6kg) passing through a 20mm IS sieve

constitute the representative soil sample initially taken for the test. Water content of

representative sample of the specimen, after conducting the above test according to

IS:2720 (Part 7) - 1980 was determined as IS:2720 (Part 2) - 1973 . The dry densities

(γd) obtained using Eqn. (C4) in a series of determinations was plotted against

corresponding moisture contents (w) and the position of the maximum of the above

202

curve ie the moisture content at which the maximum density was reached corresponds

to the optimum moisture content (OMC).

Dry Denstiy (γd) in g/ml = w

m

100100 ..(C4)

Where, w = water content of soil, in percent and γm is the bulk density in g/ml of each

compacted specimen calculated from Eqn (C5).

Density (γm) in g/ml = m

12

Vm-m .. (C5)

where, m1= mass in g of mould and base; m2 = mass in g of mould, base and soil and

Vm = volume in ml of mould.

(6) Unconfined Compressive Strength

IS:2720 (Part 10) - 1973 describes the methods for determining the unconfined

compressive strength of clayey soil both undisturbed and remoulded using controlled

strain. Unconfined compressive (UCC) strength (qu) is defined as the load at which an

unconfined cylindrical specimen of soil fail in a simple compression test. Specimens

were prepared according to the standard procedure in the above IS code and the

sample loaded in a standard UCC test setup and load applied so as to produce recorded

axial strain at a rate of 1/2 to 2 percent per minute. Force and deformation readings

were recorded at suitable intervals, until failure of specimen. Values of compressive

stress (σc) and strain ( ) were plotted and the maximum stress from the above plot

was taken as the UCC strength , qu. Stress strain values were calculated using Eqns.

(C6) to (C8).

Axial strain ( ) = 0LL ..(C6)

where ∆L= change in the specimen length as read from the strain dial indicator and L0

= initial length of the specimen.

Average cross sectional area(A) at a particular strain was calculated from Eqn. (C7)

A = -1

Ao …(C7)

where Ao = initial average cross sectional area of the specimen.

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Compressive stress ( σc) was calculated using Eqn. (C8). σc = P / A ..(C8)

where, P = compressive force and A - average cross sectional area, calculated using

Eqn. (C5).

(B) Chemical Characteristics

(1) pH

The pH of the soil samples was determined as per IS; 2720 (part 26) – 1987 –

Reaffirmed in 1997. 30 g of the soil prepared as per IS; 2720 (part 1) – 1983 (second

revision) was taken in a 100 ml. beaker and 75 ml. of distilled water was added. The

suspension was stirred for few seconds. The beaker was then covered with a cover

glass and stand for one hour, with occasional stirring. pH of all the samples were

measured using a portable digital pH meter (Model pH-201, accuracy +/- 0.01)

consisting of a glass electrode and a digital display inbuilt in the instrument.

(2) Electrical Conductivity

The electrical conductivity of the soil samples was determined as per IS;14767 – 2000. the soil samples were prepared in accordance with the above code. The electrical conductivity of soil samples were measured in the laboratory using a digital conductivity meter (Model - D1 9001, accuracy of ± 1µS / cm).

(3) Sulphate The sulphate of the soil samples was determined as per the calorimetric method prescribed in IS: 2720 (part 27) – 1977 – Reaffirmed in 1995. Sulphate in the sample is precipitated as barium sulphate in a medium containing hydrochloric acid (HCl) and barium chloride. The precipitate appears as a white turbid solution whose absorbance is measured using UV - Visible Spectrophotometer (Model: UV - 160 A; Shimanzu, Japan). The concentration of sulphate present in the sample was then obtained from the standard calibration graph obtained using known concentrations of sulphate.

(4) Chloride Chloride (Cl-) ion is one of the major inorganic anions generally present in soils. It is estimated by means of a 'volumetric procedure' using silver nitrate as the 'titrant' and

204

potassium chromate as the 'indicator'. The 'end point' is the appearance of a reddish tint precipitate. The corresponding end point burette reading (V1ml) is noted. The chloride (Cl-) concentration is then estimated using the following equation

Chloride concentration (mg/L) =

(ml) sample of volumeStandard100035.45nitratesilver ofMolarity )VV( 21

where, V1 - Burette reading corresponding to the 'end point' of sample (ml) and

V2 - Burette reading corresponding to the 'end point' of blank (Distilled water) (mL)

(5) COD COD represents the amount of oxygen required to oxidize all organic compounds

(both biodegradable and non-biodegradable) present in the soil to CO2 and water.

COD determination requires about 2 to 3 hours for digesting the organic compounds in

the presence of strong oxidizing agents using COD reflux apparatus. The best suited

oxidizing agent is K2Cr2O7. After cooling the refluxed sample to room temperature,

the excess dichromate was titrated with ferrous ammonium sulphate (FAS). The

amount of oxidisable organic matter measured as oxygen equivalent, is then taken as

COD and it is calculated as follows:

COD (mg/L) = [(A-B) molarity of FAS 8000 / (Volume of sample)]

where, A = titrant value of blank solution; B = titrant value of the sample.

(6) Total Solids (TS) and Total Dissolved Solids (TDS)

A well mixed sample was evaporated in a weighing dish and dried to a constant weight

in an oven to 103°C to 105°C and the TS of the sample is obtained using

TS (mg/L) = (w2-w1)/ Volume of sample

where, w1 = empty weight of crucible; w2 = (weight of crucible + residue).

For determining TDS, remains of the sample was filtered through a glass fibre filter

(1μm, Whatman GF) and subjected to evaporation at 103°C - 105°C, for one hour. The

TDS is then obtained using

TDS (mg/L) = (w2-w1) / Volume of sample

where, w1 = empty weight of crucible; w2 = (weight of crucible + filtrate residue).

205

APPENDIX D

MODEL CALCULATION FOR FLOW RATE (WITH RESPECT TO HRT) Flow rate for 8 hr HRT for S1 = 1.073` ml/min (Table 3.10) Diameter of soil column = 9 cm Radius = 4.5 cm Height of Soil column = 60 cm Height of soil in the column = 45 cm Liquid volume of reactor = (3.14x4.5x4.5)x45 = 2861.3 cm3 Liquid volume of reactor = V = Q x T Q = flow rate (ml/min) T = Detention time (min) 2861.3 = Q x (8 x 60) (i.e. T = 8 hr HRT) Q = 5.96 ml/min Actual flow rate for 8 hr HRT = Contaminated soil porosity x Q = 0.18 x 5.96 ml/min = 1.073 ml/min

206

APPENDIX E SCANNING ELECTRON MICROSCOPE (SEM) It is generally used in petrographic analysis of cementitious materials and microsturcture

studies of concrete and soils. SEM image provides detailed images of the microstructure of

the soils and the primary advantages are the high-contrast images of the microstructure.

It is a qualitative study and in the present study, this method was used to understand the

morphological changes that might have occurred due to the effects of wastewaters on the

soils. For SEM studies, samples were dehydrated by using an acetone series; critical point

dried and gold coated at 10-3 mm Hg in sputter coat apparatus. SEM and EDXA analysis were

carried out on Hitachi S-3400N microscope, available with Central Instrumentation Facility,

Pondicherry University, Pondicherry, India.

207

E1 (a) – SEM micrograph (magnification; x 500)

E1 (b) – EDXA profile

Figs. E1 (a – b) SEM and EDXA of soil S1 before contamination (view a)

Table E1 EDXA analysis of soil S1 before contamination (view-a)

Element Line

Weight %

Atom %

Formula

O K 43.69 58.27 O Al K 4.23 3.34 Al Si K 48.77 37.05 Si Cl K 0.27 0.16 Cl Cl L --- --- Ti K 0.42 0.19 Ti Ti L --- --- Fe K 2.27 0.87 Fe Fe L --- --- Co K 0.17 0.06 Co Co L --- --- Ni K 0.19 0.07 Ni Ni L --- --- Total 100.00 100.00

208

E2 (a) – SEM micrograph (magnification; x 3000)

E2 (b) – EDXA profile

Figs. E2 (a – b) SEM and EDXA of soil S1 before contamination (view b)

Table E2 EDXA analysis of soil S1 before contamination (view-b) Element

Line Weight %

Atom %

Formula

O K 55.30 68.99 O Al K 4.94 3.66 Al Si K 37.46 26.62 Si K K 0.27 0.14 K K L --- --- Ti K 0.11 0.05 Ti Ti L --- --- V K 0.07 0.03 V V L --- --- Fe K 0.91 0.32 Fe Fe L --- --- Zr K --- --- Zr L 0.95 0.21 Zr Zr M --- --- Total 100.00 100.00

209

APPENDIX F

X-RAY DIFFRACTION ANALYSIS It is a non destructive analytical technique which reveals information about the

crystallographic structure, chemical composition and physical properties of materials

and thin films. This technique is based on observing the scattered intensity of an X-ray

beam hitting a sample as a function of incident and scattered angle, polarization and

wavelength or energy. This is a quantitative method and using this method, the

mineralogical changes induced due to artificial contamination of wastewaters on soils

can be studied. The soil samples were analysed by powder XRD using Philips

PW1710 diffractometer available with Eath Science Department, Pondicherry

University, Pondicherry, India. It has a automatic slit under the following condition;

emission radiation – CuKα, voltage=40kV, intensity=30nA, gonimeter speed= 0.120/s.

gonimeter calibration was performed using silica standard and the data was interpreted

using X’Pert High Score. Samples were ground in agar mortar and sieved to obtain

fractions of particle size less than 53µm, for the test.

210

APPENDIX G

GAS CHROMATOGRAPH – MASS SPECTROMETER (GC-MS) It is composed of two major building blocks; the gas chromatograph and the mass

spectrometer. The gas chromatograph utilizes a capillary column which depends on the

column’s dimensions (length, diameter, film thickness) as well as the phase properties

(e.g. 5% phenyl polysiloxane). The difference in the chemical properties between

different molecules in a mixture will separate the molecules as the sample travels the

length of the column. The molecules take different amounts of time (called the

retention time) to come out of (elute from) the gas chromatograph, and this allows the

mass spectrometer downstream to capture, ionize, accelerate, deflect and detect the

ionized molecules separately. The mass spectrometer does this by breaking each

molecule into ionized fragments and detecting these fragments using their mass to

charge ratio. These two components , used together, allow a much finer degree of

substance identification.

In the present study, the organic compounds in the natural and contaminated soils are

ascertained using JEOL GC mate Gas Chromatograph – Mass Spectrometer (GC-MS)

available in Sophisticated Analytical Instruments Facility (SAIF), IIT-Madras,

Chennai, India.

211

Fig. G1 GC results of soil S1 before artificial contamination

G1 (a) – retention time 7.98 sec.

G1 (b) – retention time 10. sec.

G1 (c) – retention time 1754. sec. Figs. G1 (a – c) Mass spectroscopy of soil S1 before artificial contamination

212

Fig. G2 GC results of soil S1 due to artificial contamination of WW1 at peak

accumulation of chloride (16 h; 50%)

Fig. G2 (a) - retention time 8.03 sec.

Fig. G2 (b) – retention time 10.27 sec.

Fig. G2 © - retention time 16 sec. Figs. D2 (a – c) Mass spectroscopy of Soil S1 due to artificial contamination of

WW1 at peak accumulation of chloride (16 h; 50%) at various retention time