Divesh N. Srivastava

1
2nd Brainstorming Session on Water Quality
Analysis and Purification Techniques(August 22,
2005)

• Divesh N. Srivastava
• Media Lab Asia
• _at_ Indian Institute of Technology-Bombay

2
Quality Analysis
Parameters(As decided in last meeting) Parameters(As decided in last meeting)
On Priority Basis Others
Salinity Mercury
TDS Arsenic
Iron Sulphate
Fluoride Microbes
Nitrate
Our Sensor System
pH
Conductance
TDS
Salinity
Nitrate
Fluoride
Conductometry
Mercury
3
Brief Market Survey
pH Sensor

• BIS Limit 6.5 to 8.5.

Company Range Accuracy Basic Principle Cost(if available)
Orion, USA 0 to 14 99.9 Glass electrode, pot. ---
Toshniwal Systems Instruments Pvt. Ltd. 0 to 14 --- Glass electrode, Pot. Rs. 1000/- to 5000/- (electrode price)
Our 5 to 9 90-95 Polyaniline based, electrolyte less, pot. Few Paisa (limited reusability)(electrode cost)
4
Conductance Sensor

• Limit lt 2500 ?S/cm.

Company Range (mS/cm) Accuracy Basic Principle Cost(if available)
Orion, USA 00 to 200 99.5 Ohms Law ---
Hanna Instruments 00 to 200 98 Ohms Law 500/-(instrument electrode price)
Toshniwal Systems Instruments Pvt. Ltd. 00 to 200 --- Ohms Law Rs. 5000/- (instrument electrode price)
Our 0.1 to 3.5 95 Ohms Law Rs. 25/-(electrode cost)Reusable
5
Total Dissolved Solids (TDS) Sensor

• Conversion Factor Conductance 0.64.

• Limit lt 1600 ppm.

Company Range (ppm) Accuracy Basic Principle Cost(if available)
Orion, USA 00 to 19900 99.5 Calculated from conductance Accessory of conductivity meter
Toshniwal Systems Instruments Pvt. Ltd. --- --- Calculated from conductance Accessory of conductivity meter
Our 64 to 2240 95 Calculated from conductance Zero
6
Salinity Sensor

• Conversion Factor Chloride ion 1.648.

• Limit lt 400 ppm.

Company Range (ppm) Accuracy Basic Principle Cost(if available)
Orion, USA 00 to 80K 99.5 calculation Accessory of conductivity meter
Our 1.5 to 1500 75-90 Cl- SE calculation Rs. 1/-(electrode cost)
Further standardization in progress.
7
Nitrate Sensor

• BIS Limit lt 45 ppm.

Company Range (ppm) Accuracy Basic Principle Cost(if available)
Lazar Res. Lab., USA 0.4 to 6000 --- ISE 338/-(electrode price)
Orion, USA 0.5 to 6200 98 ISE ---
Our 6.2 to 6200 95 ISE Rs. 5/-(electrode cost)
Kits Kits Kits Kits Kits
Jal TARA --- 82 Coloration Rs. 1300/- (100 samples)
Hanna Instruments 00 to 50 N.A. Coloration 21/-
8
Fluoride Sensor

• BIS Limit lt 1.5 ppm.

Company Range (ppm) Accuracy Basic Principle Cost(if available)
Lazar Res. Lab., USA 0.02 to 1900 --- LaF3, ISE 338(price)
Orion, USA 0.02 to Saturated 98 LaF3, ISE ---
ASTI, USA --- --- LaF3, ISE ---
TPS, Australia 1.9 to 19000 93 LaF3, ISE ---
ATI, USA 0.1 to 1000 95 LaF3, ISE ---
ProMinent, 0.05 to 10 --- LaF3, ISE ---
Our 1.9 to 1900 Under investign LaF3, ISE Rs. 100/-(electrode cost)
9
Mercury Sensor

• BIS Limit lt 1.0 ppb.

Company Range (ppb) Accuracy Basic Principle Cost(if available)
NICO 2000, UK 2K to 20M --- ISE ---
Lazar Res. Lab., USA 200 to 100M --- ISE 328(price)
Our 0.03 to 0.3 60 Conducto-metry Rs. 50/-(electrode cost)
Kits Kits Kits Kits Kits
DRDO 500 --- coloration ---
Others Others Others Others Others
10 99.5 AES Rs. 1200/-(Per sample) (instrument-several lakhs)
10
Arsenic Sensor

• BIS Limit lt 10.0 ppb.

Company Range (ppb) Accuracy Basic Principle Cost(if available)
WHO release (N0210, May 2001) No reliable kit or sensor available WHO release (N0210, May 2001) No reliable kit or sensor available WHO release (N0210, May 2001) No reliable kit or sensor available WHO release (N0210, May 2001) No reliable kit or sensor available WHO release (N0210, May 2001) No reliable kit or sensor available
Kits Kits Kits Kits Kits
Jal TARA --- 82 coloration Rs. 2500/-(100 samples)
Quick II kit 0.2 to 500 55 coloration 16/-(two sample)
Others Others Others Others Others
10 99.5 AES Rs. 1200/-(Per sample)
Nano Band 1 95 Anodic Stripping 8000/-(Reusable)
11
Iron Sensor

• BIS Limit lt 300 ppb.

Company Range (ppb) Accuracy Basic Principle Cost(if available)
NO ISE NO ISE NO ISE NO ISE NO ISE
Kits Kits Kits Kits Kits
Jal TARA --- 82 coloration Rs. 1000/-(100 samples)
Others Others Others Others Others
10 99.5 AES Rs. 1200/-(Per sample)
12
Sulphate Sensor

• BIS Limit lt 200 ppm.

Company Range (ppm) Accuracy Basic Principle Cost(if available)
NICO 2000, UK 0.03 to 32K --- ISE ---
Lazar Res. Lab., USA 1.5 to 10K --- ISE 338(price)
Kits Kits Kits Kits Kits
CHEMetrics, Inc., USA 00 to 70 --- coloration 0.9 per test
13
Microbes Sensor

• Guideline Present or absent

Company Range (ppm) Accuracy Basic Principle Cost(if available)
Indirect methods- monitoring metabolic activity of the micro-organism, like BOD, OD sensors. Indirect methods- monitoring metabolic activity of the micro-organism, like BOD, OD sensors. Indirect methods- monitoring metabolic activity of the micro-organism, like BOD, OD sensors. Indirect methods- monitoring metabolic activity of the micro-organism, like BOD, OD sensors. Indirect methods- monitoring metabolic activity of the micro-organism, like BOD, OD sensors.
Kits Kits Kits Kits Kits
DRDO 1-3 coliform/100 mL --- coloration ---
Jal TARA --- 82 coloration Rs. 200/-(10 samples)
Others Others Others Others Others
Chemito Instrument Pvt. Ltd. --- --- Coloration monitoring by UV fluorescence ---
14
Thanks
15

• Quote from the fact sheet of World Health
  Organization (N0210, May-2001)
• Accurate measurement of arsenic in drinking-water
  at levels relevant to health requires laboratory
  analysis, using sophisticated and expensive
  techniques and facilities as well as trained
  staff not easily available or affordable in many
  parts of the world.
• Analytical quality control and external
  validation remain problematic.
• Field test kits can detect high levels of arsenic
  but are typically unreliable at lower
  concentrations of concern for human health.
  Reliability of field methods is yet to be fully
  evaluated.