Domestic Water Pollutions In India & Role of Science In Pollution Abatement

Table of Contents

List of Daily Activities & key Chemicals used & the non-productive output ......................... 3

List of Parameters which defines Pollution Levels in domestic wastewater ......................... 5

Mathematics to understand the impact of domestic pollution in Urban & Rural India ........ 7

What is COD & BOD and why it is been a crucial parameters for water & wastewater industry? .............................................................................................................................. 9

Ways to dispose domestic effluents in India ...................................................................... 11

Role of Science & Engineering to reduce the pollution in India .......................................... 12

Challenges In coming years & potential solutions .............................................................. 12

List of Daily Activities & key Chemicals used & the non-productive output Daily Activity

Product/Chemicals used

Wastewater Generation (Litre per day per person)

Key Ingredients in Wastewater (Non Productive Outputs) Approximate consumption per day per person

Tooth Brush

Tooth Paste 1-2 Tricoslan (Anti-Bacterial), Propylene Glycol (To drop freezing point of tooth paste), PEG12 (to improve texture of toothpaste), Sodium Laurel Sulfate (Creates Foam), Sodium Saccharin (Artificial Sweetner), Lactose Monohydrate (Milk Sugar)

0.5-1 gm

Shaving Shaving cream 2-4 Stearic Acid (Opacifying Agent& Surfactants), Dimethicone (Antifoaming agent, hair Conditioning agent, skin conditioning agent, skin protectant), Glycerin (humectant), Butane (aerosol propellant), Isobutane(aerosol propellant, Propoane (aerosol propellant), Laureth-23 (Surfactants & emulsifying agent) , Panthenol (Lubricant on Skin) , Sodium Laureth Sulfate (Surfactants & cleansing agent), Triethanolamine (to reduce surface tension), Fragrance, Botanical Ingredients, Color Additives

1-2 gm

Toilet 10-20 Feces (which comprise of 75% moisture, 20% Organic Solids (25-54% bacterial mass, 2-25% protein & nitrogenous matter, 25% carbohydrate and 2-15% fat) & 5% Inorganic solids) and unmetabolized Medicines of various nature

250-400 gm

Urination 5-10 Urine is an aqueous solution of greater than 95% water. Other constituents include urea, chloride, sodium, potassium, creatinine and other dissolved ions, and inorganic and organic compounds.

0.75-1.25 Liters

Hand Wash & Face Wash

Soaps 1-2 Sodium laureth sulfate (Detergent), lauramidopropyl betaine (Foam Booster & thickener), glycerine, laureth-4, parfum,

2-3 gm

sodium chloride, sodium lactate, cocamidopropyl PG-dimonium chloride phosphate (antibacterial), polyquaternium-39, citric acid, hexylene glycol (moisturizing agent), sodium citrate, sodium benzoate (antibacterial), tetrasodium EDTA (Preservative), methyldibromo glutaronitrile (antibacterial agent), phenoxyethanol (antibacterial agent & solvent), methylparaben (preservative), propylparaben (preservatives), sodium benzotriazolyl butylphenol sulfate, buteth-3, tributyl citrate, citronellol, butylphenyl methylpropional, linalool, alpha isomethyl ionone (fragrance), hexyl cinnamal, limonene, CI 42051 (color agent)

Bathing Soaps & Shampoos

25-40 Same as above with few addition & deletion 2-3 gm

Utensils Washing

Soaps and Oil 4-5 Same as above (with few additions & deletion 2-3 gm

Cloth Washing

Soaps & Detergents

40-50 Cleaning agents (anionic and nonionic surfactants, enzymes), water softeners (sodium carbonate and sodium aluminosilicate), fabric whitener, sodium perborate, anti-redeposition agent, perfume, washer protection agent (sodium silicate) and processing aids (sodium sulfate)

2-3 gm

Floor Mopping

Floor Cleansers 4-5 Variety of chemicals are used as floor mopping 1-2 gm

Misc. 5-10 Average Wastewater Generation

108-163 50-100 chemicals are used directly*

*the chemicals used gets diluted by the fresh water used throughout the day.

List of Parameters which defines Pollution Levels in domestic wastewater

Parameters Meaning Significance Unit of

Measurement Chemical Oxygen Demand (COD)*

The amount of oxygen required to oxidise organic carbon: tested through chemical oxidation.

1000 ppm COD means 1000 mg of Oxygen is required to completely oxidize organic carbon to CO2 through chemical oxidation for 1 Litre of sample.

Ppm ( or mg/l) (1 ppm = 1 mg/l)

Biological Oxygen Demand (BOD)

The amount of oxygen required to oxidise organic carbon: tested through biological ways.

1000 ppm BOD means 1000 mg of dissolved Oxygen is required to completely oxidize organic carbon to CO2 through

Ppm ( or mg/l) (1 ppm = 1 mg/l)

Pollutants in water

Soluble

Organic Matter

like Sugar, Color, Glucose, Microbial,

Viruses etc.

Paramters used to measure

{COD, BOD, pH, TDS, colour}

Inorganic Matter

Common Salt, Baking soda, all types of soluble

salts, Ammoniacal Nitrogen etc.

Paramters used to measure

{TDS, Chlorides, Sulfates, Phosphorus, Nitrogen,

Heavy Metals etc.}

Insoluble

Organic Matter

Milk, Soaps, Emulsion, Oils etc.

Paramters used to measure

{COD, BOD, pH, TSS, O&G etc.}

Inorganic Matter

Silt, Clay etc.

Paramters used to measure

{TSS, Turbidity, colour}

biological oxidation for 1 Litre of sample.

Total Suspended Solids (TSS)

The amount of insoluble impurities which is more than 0.1 micron meters in diameters. Filtered on Wattman’s Filter paper.

1000 ppm of TSS means 1000 mg of suspended mass (in dry form) was observed in 1 Litre of sample.

Ppm ( or mg/l) (1 ppm = 1 mg/l)

Total Dissolved Solids (TDS)

The amount of total solids collected after complete evaporation of water from the wastewater sample.

1000 ppm of TDS means 1000 mg of dissolved salt was observed after filtering the TSS content behind every 1 litre of sample.

Ppm ( or mg/l) (1 ppm = 1 mg/l)

pH Represents the hydrogen ion concentration

Oil & Grease This represent the floating materials which are emulsion in nature

1000 ppm of O&G means 1000 mg of Oil content is floating in every 1 Litre of sample.

Ppm ( or mg/l) (1 ppm = 1 mg/l)

Coliforms Bacterial impurities in the faecal matters.

Higher the CFU means more concentration of biomass.

Colony Forming Unit (CFU)

Total Nitrogen

The total nitogen means the inorganic nitrogen as well as organic nitrogen bound with organic matter

Higher the total nitrogen in the wastewater indicates high chances of eutrophication

Ppm ( or mg/l)

Ammoniacal Nitrogen

It represents the mass of ammoniacal nitrogen (NH4+) (which is inorganic in nature)

Higher the Ammoniacal Nitrogen in the wastewater indicates high chances of eutrophication

(1 ppm = 1 mg/l)

Nitrate Nitrogen

It represents the mass of nitrate nitrogen ( (which is inorganic in nature)

Higher the nitrate nitrogen in the wastewater indicates high chances of eutrophication

Ppm ( or mg/l)

Phosphates It represent the mass of phosphates PO43-

Higher the phosphate in the wastewater indicates high chances of eutrophication

(1 ppm = 1 mg/l)

*COD

Mathematics to understand the impact of domestic pollution in Urban & Rural India

A note on the above illustration:

• COD is always more than BOD, in domestic wastewater the COD is 2.5 to 3.5 times more than BOD in general.

• Total solids in wastewater is a sum of salts + suspended solids, for example a water containing 2 gm of table salt in 1 litre of water + 5 gm of dust of wood in 1 litre than the total solids in the water will be 7 gm in 1 litre.

• O&G is immiscible contents in the water which floats at the surface & are organic in nature.

• Domestic wastewater contains significant microbes concentration like 104-105 CFU/100 ml of wastewater means, 10000 -100000 independent colonies can grow if proper environment is given for 100 ml of wastewater.

• Nitrates & ammoniacal nitrogen & phosphates are considered to be essential nutrient to support microbial growth & important for eutrophication

Few Calculation on the parameters Illustration # 1 Find out the pollution load of wastewater in Kg/Day for the following data considering the wastewater generated per day is 1000 cubic meter / day.

1) COD – 300 ppm (mg/l)

2) BOD – 150 ppm (mg/l) 3) TDS – 400 ppm (mg/l) 4) TSS- 150 ppm (mg/l) 5) TS – 500 ppm (mg/l) 6) Coliform – 105 CFU/100 ml 7) O&G – 30 ppm 8) Ammoniacal Nitrogen – 40 ppm (mg/l) 9) Phosphate – 30 ppm (mg/l)

Solution: Parameters Value in mg/l Volume per

day Kg parameter /day

COD 300 1000X1000 = 1000000 litre/day

={300X1000000}/{1000X1000} =300 kg/day

BOD 150 1000000 l/day 150 kg/day TDS 400 1000000 l/day 400 kg/day TSS 150 1000000 l/day 150 kg/day TS 500 1000000 l/day 500 kg/day Coliform 105 (CFU/100ml) 1000000 l/day 106X106 CFU/day O&G 30 1000000 l/day 30 Kg/day NH4-N 40 1000000 l/day 40 Kg/day Phosphates 30 1000000 l/day 30 Kg/day

Illustration # 2 A city which houses a population of 10,00,000 people who consumes fresh water @ 120 litre per day per person & generates 100 litres as wastewater with following parameters:

1) COD – 300 ppm (mg/l) 2) BOD – 150 ppm (mg/l) 3) TDS – 400 ppm (mg/l) 4) TSS- 150 ppm (mg/l) 5) TS – 500 ppm (mg/l)

70% of the wastewater is collected & treated by local municipalities & 30% goes untreated in the water bodies. Comment on the seriousness of the issue & justify. Solution: Parameters Value

in mg/l Volume per day Kg parameter /day 30% gets no

treatment COD 300 1000000*100=108

Litres per day ={300X10^8}/{1000X1000} =30000 Kg/day

=9000 kg/day

BOD 150 1000000*100=108 Litres per day

={150X10^8}/{1000X1000} =15000 Kg/day

=4500 kg/day

TDS 400 1000000*100=108 Litres per day

={400X10^8}/{1000X1000 =40000 Kg/day

=12000 kg/day

TSS 150 1000000*100=108 Litres per day

=15000 Kg/day =4500 kg/day

TS 500 1000000*100=108 Litres per day

=50000 kg/day =15000 kg/day

The concern is very severe because the mass of COD released in environment will consume DO of the water body & can detoriate the fresh water to the tune of ={9000/0.007} = 12.85 lacs cubic meters of fresh water & at the same time other parameters will get diluted in the water.

What is COD & BOD and why it is been a crucial parameters for water & wastewater industry?

• Our rivers & surface water bodies which carries fresh water received through precipitation or from melting of glaciers, the water contains necessary minerals to support lives at various layers on the planet earth.

• Even, water in clean rivers prevails aquatic life to sustain and the only reason for such an existence of the aquatic life is available dissolved oxygen in the clean water.

• Available dissolved oxygen in the water can reach up to 7-8 mg/l of water. • Now, you can understand the impact of pollution, if high COD/BOD laden

wastewater is discharged to the river than the available dissolved oxygen in the water is destroyed by the impurities through microbial actions.

An Illustration for the above bullet points:

A note on the above illustration:

• A river which is flowing @ of 5000 cubic meter / day (5000X1000 l/day = 50 lacs litre/day) carries fresh water with high Dissolved oxygen (DO) at 7-8 mg behind every litre of water.

• This means a total of 35 kg of DO is available in the river which is carrying 50 lacs litre of fresh water & on the same aquatic life is surviving.

• Now, a township located next to river is illegally dumping its wastewater into the river @ 2000 cubic meter/day with 0 DO & high COD i.e. 300 mg/l of wastewater.

• It means (2000X1000X300)/(1000X1000) = 600 kg/day of COD is carried by the wastewater stream to the river.

• Interestingly, the wastewater does also carry human faecal matter which is rich in microbes & are searching for a favourable conditions in which they can grow & consume DO with impurities.

• Now, both fresh stream of river & wastewater stream from township mixes together & makes a net water volume around (2000 + 5000 = 7000 m3/d) with new concertation of COD as = {600 kg (from township) + 25 kg (inherent in river)} = 625 kg of COD / 7000 m3 of water = 0.09 kg/m3 or 90 mg/l.

• Similarly, DO can be calculated = {35 kg in river + 0 kg in township water = 35 kg/day}/7000 m3 = 5 ppm

• Now, you can see the available DO is 5 ppm & the demand is of 90 ppm, which means the microbes present in the township wastewater will take away COD in presence of DO, therefore the DO is scavenged by the microbes & pollution impacts the river & aquatic life.

• That is the reason, location 5 is shown with 0 DO & COD is still high. These are the major threats to our river in the cities/rural areas where proper wastewater treatment is not designed & implemented.

Ways to dispose domestic effluents in India

A note on the above mentioned illustrations:

• Case -1: In India, we collect & treat the sewage/domestic wastewater & treat it to the norms prescribed by Indian Govt. & release it in the open water bodies

• Case -2 Many big townships do treat the domestic wastewater & partially recycle it for non-potable purposes & release remaining into the govt treatment plants along with small township wastewater

• Case-3 Township domestic wastewater is collected by industries for their own needs & do the treatment as per the need & reuse the domestic water, an example set by Rashtriya Chemical Fertilisers in Mumbai

• Case-4 Township domestic wastewater is not been collected & directly dumped into water bodies (a major problem in India of every states)

• Case-5 Township wastewater is collected & disposed off into deep sea without any treatments, in Mumbai around 4000 Million Litre Water per day is disposed of in the same way.

Role of Science & Engineering to reduce the pollution in India

1) Collection & distribution Science of the wastewater & treated water respectively. a. It involves major skills from Civil Engineering, mechanical engineering for

execute & implement such a mega projects.

2) Pollution treatment plant a. For this work, Environment Engineering, Civil Engineering, Chemical

Engineering, Biotechnology, Microbiologist, Chemistry are the core discipline A typical domestic water treatment plant:

Challenges In coming years & potential solutions

1) Water Scarcity

2) Raising demands of fresh water

3) Raising demand of chemicals which will be drained to the environment system

4) Potential Solutions : Treat & Recycle the domestic wastewater by certain percentages like 20/30/40/50 etc..