imn 01 wastewater characteristics

7/23/2019 IMN 01 Wastewater Characteristics

http://slidepdf.com/reader/full/imn-01-wastewater-characteristics 1/26

• – , ,

• Recent Tren s:

• Separation of

Grey

water

– Dual

plumbing

• ns te treatment an reuse o grey water

• Reuse of treated water

•



• Advanta es

Both rainwater

and

waste

water

Sewers large in size, easy to clean, does not choke

Dilution of wastewater and gases

• Disadvantages ,

Load on treatment plant increases

Over flow during storms, siltation in dry seasons

Choice is based on funds, rainfall pattern, topography, soil , , .



• 80% of water supplied provided no additional source of water

• Minimum – 150 l cd

• Infiltration‐

• Area Basis – 0.2 to 28 m3/ ha/day

• Lengt Basis ‐ 10,000 to 50,000 m ay

• Diameter length Basis

• Desi n Period

» Sewers – 30 years

» Pumping stations – 5 to 10 years

» Treatment lants – 10 to 30 ears

• Population Forecast

Arithmetic mean method

Logistic Curve method



• Varies every hour , every day, every season

• Both maximum

and

minimum

rate

of

flow

is

vitalow var a ons a ec per ormance o sewer,

pumping station and treatment plants

• Maximum Flow

– Peak factors are decided based on the

component designed.

• Minimum Flow ‐ laterals are largely impacted



SewerSewer

Factor to multiplyFactor to multiply

raterate

1. domestic sewer 1. domestic sewer 66

2.lateral sewer 2.lateral sewer 44 _ _ 66

3.branch sewer 3.branch sewer 33

4.main sewer 4.main sewer 22..55

Peak factors based on population

5.trunk or outfall5.trunk or outfall 22 SS NoNo

11.. UpUp toto 2020,,000000 33..55

22.. 2020,,000000 toto 5050,,000000'' 22..55

.. ,, oo ,, ..

44.. aboveabove 750750,,000000

22..00



Waste water Characteristicsaste water Characteristicsaste water Characteristicsaste water Characteristics

D fi itifi itiefinitionefinition = p ys ca , c em ca , o og cap ys ca , c em ca , o og ca

TTypespes:

Infectious Agentsnfectious Agentsnfectious Agentsnfectious Agents

Oxygenxygen-Demandingemanding Wastesastes

Nutrientsutrients

Inorganic Pollutantsnorganic Pollutants

Organic Chemicalsrganic Chemicals

))ediment Particulates)ediment Particulates)

Thermal Pollutionhermal Pollution



Infectious

Infectious AgentsAgents

Each person discharges about 100 to 400 billion coliform

bacteria per dayInfectiousnfectious Agentsgents == pathogenicpathogenic organismsorganisms.. WaterWater--borneborne

,,

cholera,cholera, bacterialbacterial andand amoebicamoebic dysentery,dysentery, polio,polio,

infectiousinfectious hepatitis,hepatitis, guineaguinea wormworm andandsc stosom as ssc stosom as s..

Analyzenalyze coliformoliform

bacteriaacteria ((E E.. coli coli ))..PresumePresume ifif coliformcoliform

,,

infectiousinfectious pathogenspathogensareare alsoalso presentpresent..



• Se arate determination of Total Coliform TC Fecal

Coliform (FC)

and

Fecal

Streptococci

(FS)

is

now

possible.

• resence o an pa ogen c organ sm oge er s

well established and FC is the widely used bacterial

parameter as

indicator

of

fecal

pollution.

• FC/FS ratio for human beings is more than 4, whereas

FC/FS ratio for domestic animals is less than 1.

Thus FC FS

ratio

can

be

used

to

find

whether

suspected

contamination of water is derived from human or animal waste.



O D di Wdi Wxygenxygen-Demanding Wastesemanding Wastes

OxygenOxygen dissolveddissolved inin waterwater isis indicatorindicator ofof waterwater

qualityquality.. 66 ppmppm OO22 oror moremore supportssupports desirabledesirable aquaticaquatic

lifelife..

BODODODOD oc em caoc em ca oxygenoxygen emaneman measuresmeasures ee

amountamount ofof dissolveddissolved oxygenoxygen consumedconsumed byby aquaticaquatic

microorganismsmicroorganisms.. Sewage,Sewage, paperpaper pulp,pulp, oror foodfood wasteswastescancan causecause anan Oxygenxygen sag,ag, wherewhere fewfew fishfish survivesurvive..



• Eutrophication is the natural process by which waters (lakes,rivers etc) become excessively enriched with nutrients,typically nitrogen and phosphorus.

• Human activities often enhance the rate of change due toactivities such as farmin forestr industr and wastetreatment that cause nutrients to enter watercourses.



I i P lli P llnorganic Pollutantsnorganic Pollutants

Heavy metals, like mercury, lead, tin, cadmium,Heavy metals, like mercury, lead, tin, cadmium,

selenium, andselenium, and arsenicarsenic--batteries, paints,batteries, paints,

Mother and SonMother and Son

Minamata Bay, JapanMinamata Bay, Japan




Mercury poisoningercury poisoningercury poisoningercury poisoning

CausesCauses:: -- damage to the nervous systemdamage to the nervous systemmetalmetal retardation cerebralretardation cerebral alsals

development delays, kidneydevelopment delays, kidney disordersdisorders

Leadead poisoningoisoning

Causes:Causes: -- miscarriagesmiscarriages

---- learning disabilitieslearning disabilities




N t lli S ltonmetallic Salts:

Arsenicrsenic CausesCauses:: -- anemiaanemia

-- cancercancer

-- death.death.

Sodiumodium Chloride:hloride: SalinizationSalinization

Sulfurulfur and nitrogen compoundsnd nitrogen compounds

ausesauses:: -- p c anges w c a ec spec esp c anges w c a ec spec es-- leaches aluminumleaches aluminum



POPsPOPs

PersistentPersistent OrganicOrganic PollutantsPollutants (POPs)(POPs) areare chemical

substances that persist in the environment,

oaccumu a e roug e oo we , an pose a r s o

causing adverse effects to human health and the

.

TheThe "dirty"dirty dozen"dozen" includesincludes:: PCBs,PCBs, aldrin,aldrin, chlordane,chlordane, DDT,DDT,

dieldrin,dieldrin, endrin,endrin, heptachlor,heptachlor, hexachlorbenzene,hexachlorbenzene, mirex,mirex,polychlorinatedpolychlorinated dibenzodibenzo‐‐pp‐‐dioxins,dioxins, polychlorinatedpolychlorinated

enzo urans,enzo urans, anan toxap enetoxap ene..



Organicrganic Pollutantsollutants - Effectsffects

TheyThey areare notnot metabolizedmetabolized veryvery rapidlyrapidly byby

an ma san ma s;; nstea ,nstea , tt ss epos teepos te anan storestore nn

thethe fattyfatty tissuestissues biomagnificationbiomagnification



Typical wastewater CharacteristicsMAJOR CONSTITUENTS OF TYPICAL DOMESTIC WASTEWATER

All Concentrations in mg/l

Strong Medium Weak

Dissolved solids (TDS)1 850 500 250

Suspended solids 350 200 100

Constituent Concentration, mg/l

Nitrogen (as N) 85 40 20

Phosphorus (as P) 20 10 6

Chloride 100 50 30

Alkalinity (as CaCO3) 200 100 50

Grease 150 100 50

BOD52

COD

300

400

200

250

100

175



POSSIBLE LEVELS OF PATHOGENS IN WASTEWATER

Type of pathogen Possible concentration in Nos per

wastewater(Based on 100 lpcd of

municipal sewage

and

90%

inactivation

of excreted pathogens)

Viruses: Enteroviruses 5000

Bacteria: Pathogenic E. col Uncertain

.

Shigella spp. 7000

Vibrio cholerae 1000

Helminths: Ascaris Lumbricoides 600

Hookworms 32

Taenia saginata 10

Trichuris trichiura 120



Primar ollution- BOD, COD, N, P, K

from wastewater

Secondary pollution – Eutrophication,

the oxygen demand caused by it

Combined sewage has high values of all nutrientsSoil infiltration locks phosporus by

ionexchange and hence prevents eutrophication



Decomposition

ratesReadily available organic matter is

the digestive process

Hence do not rapidly decompose

% Nitrogen compounds high in urine

Nitrification takes along time to pick up

Organics kitchen waste, etc



•

• Agriculture

• Lan scaping

• Aquifer recharge

• Surface water recharge

•

• Domestic water supply

imn 01 wastewater characteristics

Documents