Microsoft Powerpoint - Technical Presentation on Bio-Towers[1]

8/13/2019 Microsoft Powerpoint - Technical Presentation on Bio-Towers[1]

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BY

SAI ENVIRO ENGINEERS PVT. LTD.


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BIOLOGICAL TREATMENT SYSTEMS

A Biological Treatment (secondary) which removes the

dissolved organic matter from the waste water can be

categorized into different systems primarily based on the

bacterial growth pattern.

Suspended Growth : Bacteria is in suspension in the reactor,

, .

Ex : Activated Sludge Process (ASP), Extended Aeration, etc.

Attached Growth : Bacteria attached to a surface of media,

no mobility, no loss of microbes, Media with higher surfacearea provided for bacterial growth.

Ex : SAFF, FAB, Bio-towers, etc.


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CONCEPT

Bio-tower is a modernizedtrickling filter which isdesigned as a roughening tower

for BOD COD reductionfrom the influent.

Bio-tower is used as a firststage aerobic biologicaltreatment where multi stagetreatment is required.


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WHY and WHERE ?Why Bio-tower ?

Bio-tower is equipped with PVC structured media which provides

larger surface area in the tune of 100m2/m3, hence it occupies less

space.

No lateral load of media and is self supporting, hence skeletal civilstructure suffices. This results in low construction costs.

Low power consumption - to the tune of up to 1/4 th ofth .

A bio-tower system can reduce upto 60 80% BOD easily when two

towers are equipped in series.

Where ?

A bio-tower can be used where a multi stage biological treatment

process is required to break the complex organics.

A bio-tower can be used where the system is required to take careof shock loads in terms of both hydraulic and organic disturbances.


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APPLICATIONS

Municipal Sewage

Pharmaceutical Industry

Distillery

Paper Mill, Paint

Food Processing

Dairy

Sugar

Brewery


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CONSTRUCTION AND MECHANISM

Bio-tower is constructed with Civil Columns and beam

supports. Bio-tower is filled with PVC structured bio-fill

media.

A recirculation pump arrangement shall be made at the sumpto feed the effluent to the top of the tower and sprinkle, where

the media adhered micro-organisms will degrade the organic

.

rate of bio-fill media.

Part of the effluent from recirculation line flows to next unit

for further treatment.

Bio-tower will not clog as like ordinary stone media filters.

Excess biomass on the Bio-tower plastic media automaticallyremoved due to the recirculation flow.


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BIO-FILL MEDIA

Synthetic media in a bio tower

system results in a greatersurface area available for

biological growth per cubic mtr.

- .

Because of the less weight of

synthetic media, bio-towers can

be built upto 6 mtrs. This results

in the ability to handle greater

loads.


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INSTALLATION OF A BIO-TOWER SYSTEM


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Aerobic bacteria clings to the surface of

media and stays in the system in the

form of biofilmOrganic matter in wastewater comes in

contact with the bacteria

TREATMENT PROCESS IN BIOTOWER

ac er a consumes e organ c ma er

and releases CO2, H20, HUMUS

As the layer grows in thickness, bottom layers turns into anaerobicbecause of lack of O2

Also, organic matter does not reach bottom layers and the bacteria goes

into endogenous phase and gets detached from media. This is called

SLOUGHING


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ADVANTAGES OF BIO-TOWER SYSTEM

Attached growth systems can take more shock loads interms of hydraulic and organic disturbances as compared tosuspended growth systems.

High purification rates.Trouble free operations even underdifficult conditions.

Semi skilled operation, very less maintenance requirementsand thuslow operation and maintenance costs.

Void ratiois more than 95% and hence media height can be

up to 7-8mtrs.

Low sludge production about 0.15-0.2kg/kgBOD reduced(ASP-0.3-0.4kg/kgBOD; EA-0.25-0.3kg/kgBOD)


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Lower residual suspended solids concentration in treated

wastewater is observed.

A bio-tower serves as a cost effective combination with other

treatment methods.

Less foot print arearequired compared to conventional system.

significantly reduced bio-tower size & cost and enhanced theirefficiencies.

No need for Mechanical or Diffused Aeration. This works on

Natural Draft.


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General Advantages of Structured Media For Bio-tower

a. Long life of over 30 years - UV stabilized material.b. Large specific surface area - 100 Sq. m / Cu. m

c. Very large voidage >97 %.

d. Low dry weight 30 kg / Cu. m leads to cheaper & simplersupporting structure.

e. The distribution pattern ( 600 cross fluted ) provides

f. Large heights - say 6 - 8 M - Allow considerable saving of land

g. Due to cross flow configuration, liquid has about 4 times

higher detention time.

h. Good wetting, continuous air movement and thinnerbiological growth lead to ZERO fly nuisance


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COMPARATIVE STUDY


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DESCRIPTION CONVENTIONAL

Aeration System

Bio-Tower/

Trickling Filter

Flow rate 1000 m3/day

41.66 m3/hr

1000 m3/day

41.66 m3/hr

BOD Inlet 250 mg/lit=250 kg/d

250 mg/lit=250 kg/d

Volume of Tank 334 m3 215 m3

Tank depth 2.5 m 6.0 m

Tank dimensions Diameter: 13m 6m x 6m

Area Required 133 m2 36 m2

Actual Air Requirement 700 m3/hr Natural Draft Air is sufficient

Sludge Recirculation Required to maintainMLSS concentration

N.A.Large Microbial growth on

media suffices

Pumping Requirement Yes Yes


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COST ANALYSIS

DESCRIPTION CONVENTIONAL

aeration System

Bio-Tower/

Trickling Filter

Land Requirement =133+(0.3*133)

= 172 Sq.m

=36+(0.3*36)

= 50.00Sq.m

Land costLand Cost @ Rs 250

/ Sqm.

Total Land costRs 43,000/-

Total Land costRs 12,500/-

Civil Work Volume of tank=334 m3

Civil cost

@Rs.2000/m3=

Rs.6,68,000/-

Cost of Frame Work=

Rs.1,00,000/-

Bio Tower Media N.A. 170 cu.m x 3000

= Rs.5,10,000/-


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COST ANALYSIS

DESCRIPTION CONVENTIONAL Aeration

System

Bio-Tower/

Trickling Filter

Diffused Aerationsystem

Diffuser cost = 82 Nos. x5000 = Rs. 4,10,000/-

Air Piping= Rs. 1,00,000/-

N.A.

Water Distribution N.A. Rs.50,000/-

system

Pump Requirement 2 (1W + 1SB)

=Rs. 2,00,000/-

2 (1W + 1SB)

=Rs. 4,00,000/-

Blower Assembly 2 (1W + 1SB)

=Rs.4,00,000/-

N.A.

TOTAL COST =18.2 Lacs =10.72 Lacs


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PARTIAL LIST OF BIO-TOWER

INSTALLATIONS

&

&


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THANK YOU

SAI ENVIRO ENGINEERS PVT. LTD.

Documents

Microsoft Powerpoint - Technical Presentation on Bio-Towers[1]