Wastewater Treatment & Recycle Options

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contents changing scenario

treatment requirements conventional ASP

technology options

SBR

MBR

About SBR

About MBR

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Changing Scenario

forWastewater treatment

1980 2010

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Changing Scenario

WastewaterDisposal

WastewaterRecycle

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Wastewater disposal to recycle

Process UnitCooling Tower

Effluent TreatmentPlant

Previously

DISPOSAL

Process UnitCooling Tower

EffluentTreatment Plant

Presently

20-30%

DISPOSALRecycle

70-80% RECYCLE

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Sewage disposal to recycle

Resi &Commercial

Buildings

Sewage TreatmentPlant

Previously

DISPOSAL

Resi &Commercial

Buildings

SewageTreatment Plant

Presently

0%

DISPOSALRecycle

100% RECYCLEfor Non Drinking

Applications 5


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Changing Scenario

Meet DisposalNorms

Meet RecycleNorms

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recycle normsParameter Disposal

normsRecycle norms

Low end reuse High end reuse

TSS 100 < 5 < 1 ntu

BOD 100 < 10 Nil

COD 250 < 50 Nil

SDI No limit No limit < 3

TKN 100 No limit < 1

T- N No limit No limit < 5

T- P 5 No limit < 1

Bacteria No limit No limit Nil

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Changing Scenario

Low TechLow Cost

L1

Cost BenefitAnalysis

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Cost Benefit Analysis

1. Benefit vs Additional cost

2. Payback of Additional cost

3. Life cycle analysis

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meeting the challenge of the

new decade.

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technology option

1. SBR

Sequential batch reactor

2. MBR

Membrane bio reactor technology

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Conventional ASP

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limitations of conventional activated

sludge process.

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System dependent on inefficient settlingmechanism

Settling units are prone to problems of poor

settling and frequent floc carry over due to

bulking , de nitrification .

Complete plant operation is normallyoperator dependent

limitation of conventional ASP

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limitation of conventional ASP.

No mechanism to control type of micro-organism in the aeration tank

No inbuilt feature for nitrification / de

nitrification

No feature for phosphorous removal

Need for large diameter secondary clarifier to

settle the light bio flocs

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how to overcome these

problems.?

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Sequence Batch Reactor (SBR)

1. Fill 3. Settle

4. Decant

2. React (Aerate)Screened /degrittedInfluent TWL

EffluentSludge

5. Idle

Bi l i l i


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Biological reactions

Biodegradation (aerobic)

Organics (BOD) + O2 + Nutrients + Bacteria = New Bacteria + C02 + H20

Nitrification (aerobic)

NH3-N + O2 + Nitrosomonas = NO2 + O2 + Nitrobacter = NO3

De nitrification (anoxic)

NO3 + organic substrate + Hetrotropic = N2 + CO2 + H2O + New cells

Phosphorous removal (anoxic/anaerobic aerobic)

VFA(organics) + Acinetobactor = release O-P

O-P + Bacteria + O2= new cells + cell maintenance

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Screened InfluentBaffle Wall Decanter

Pre-react Chamber

Main-react

Chamber

Effluent DischargeDiffusers

Mixers

SAS

Pumps

SBR

ITT Corporation India Pvt.Ltd.


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SBR Basin Equipment

DissolvedOxygen

UltrasonicLevel

Float Switch

Penstock

EffluentInfluentFrom

Inlet Works

M

M

Decanter

M

To SASStorage

SAS Pump

S

Grid 2Grid 1 Grid 3

M Air Flow

Blowers

Air Purge

Air Inlet Valve


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Outlet quality (all units in ppm)

Srno Parameter SBR ASP

1. BOD 10 30

2. COD 50 250 300

3. TSS 10 100

4. TN


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theSBR advantage.

+ Single tank design compact layout

+ Excellent outlet quality low end reuse

+ Low operating cost typically 40-50% lowerthan conventional system

+ Intelligent cycle control auto PLC

+ Pre react basin

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theSBR advantage.

+ Respiration rate control

+ nitrification / de nitrification

+ Bio P control

+ High turn down ratio

+ Minimal moving parts

+ Decanter in SS construction

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MBR

Membrane Bio - Reactor

technology

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it is a very high efficiency process

with outlet quality as feed toReverse Osmosis .

MBR

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areas of application.

as pretreatment to RO , in place ofconventional ultra filtration systems

To achieve very high efficiency of more than98%

To have most compact layouts

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MBR System Schematics

INLET

AIR

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advantages of MBR

+ Buildup of very high MLSS , 5-6 times more

than conventional process

+ Extremely Compact layout

+ High efficiency process

+ Fully automatic PLC plant

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advantages of MBR

+ Inherent capacity to handle shocks

+ No need for downstream tertiary treatment

units

+ Easy future expansion

+ Treated effluent can be fed directly to RO

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Outlet quality (all units in ppm)

Srno Paramete

r

SBR MBR ASP

1. BOD 10 5 30

2. COD 50 25 250 300

3. TSS 10 < 0.5 100

4. TN

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Wastewater Treatment & Recycle Options