Feasibility Report_110 KLD

8/3/2019 Feasibility Report_110 KLD

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This report details the following from the proposed facility. Collection,Treatment and Disposal of Domestic Effluents.

QUANTITY AND QUALITY OF WASTEWATERS.

The population and water demand is enclosed in ANNEXURE 1.

Principal source of water supply for the proposed developments is available from BWSSB. Tankerwater supply is considered for additional requirements.

The wastewater quantity from domestic sources is considered at maximum of80% of water consumed. Hence the quantity of wastewater generated is asbelow

Quantity of water consumed = 138 cum/dayQuantity of wastewater flow = 110 cum/day

Treatment plant for treating sewage in the building has been proposed for acapacity of 110 cum/day.

Proposed quality of raw and treated sewage is as below

Quality of raw waste-water:PH = 6 8

TSS = 200 - 400 Mg / LitBOD5 = 200 - 350 Mg/LitCOD = 500 - 700 Mg/Lit

Turbidity = 10 15 NTUResidual chlorine = Present / AbsentE Coli = Present

Quality of treated waste water:PH = 7.0 8.0

TSS =


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Secondary Treatment : For reduction of BOD / COD of sewage.

Tertiary Treatment : For finishing and removal of traces of impurities fromtreated sewage water.

The treatment methodology comprises of the following units.a) Bar screenb) Collection and equalizationc) Aeration (Extended Aeration & Activated Sludge)d) Clarifiere) Secondary Aeration (Extended Aeration & Activated Sludge)f) Secondary clarifierg) Clarified water tank.h) Sludge re-circulationi) Sludge holding tank

j) Filter pressk) Final Sump

l) Pressure Sand Filtration & Activated Carbon Filtration, softeningm) Disinfection by On-line Chlorination

Following is a description of individual treatment units, with their designcriteria, dimensions, mechanical equipment selection etc.,

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ESCRIPTION OF TREATMENT UNITS

A. BAR SCREENIn the incoming channel, a chamber medium screen shall be fitted, thepurpose of which is to filter out coarse trashy matter from introducinginto succeeding units of the treatment plant. Screens shall be made of

M.S Construction with Epoxy Painted.Channel Size : 700 Wide x 1500 Long x 800 Depth

Type of screen : M.S Construction manually cleaned with MSflats placed at 20 mm c/c with MS hand rakewith handle all epoxy painted.

B. EQUALISATION TANK / COLLECTION TANKIn order to homogenize the quality of wastewater, as well as to feedwastewater at a uniform rate to the rest of the treatment plant, anequalization tank is proposed. In order to mix the contents, as well as toprovide a degree of preparation, diffused aeration by means ofmembranes and blowers are proposed.

Capacity : 37 CumSize : 5300mm x 1800mm x 4500mm DepthAeration : Coarse diffuserD.P : 6 Hrs.

C.AERATION TANKThe sewage thus received in the aeration tank is treated by extendedaeration biological treatment in the chamber. The aeration tank isprovided with membrane type air diffusers. The main air header isconnected to a rotary lobe type blower, which delivers the requiredquantum of air to the system. The raising bubbles from the diffusionmembranes scrub the water more efficiently causing molecular diffusionand enhance the dissolved oxygen level in the effluent. With organicmatter as food and oxygen for respiration, the aerobic bacterial volumeincreases day by day and starts consuming the organic matter present inthe water. In order to keep the bacterial volume high, the aerated wateris decanted to separate the bacterial flock and the same is re-circulatedto the aeration tank. The raising bubbles from the membrane diffusersalso keep the content of the aeration tank in a turbulent mode therebycausing intimate mixing of bacterial volume and organic matter presentin the effluent for more uniform digestion of the organic matter. Thiswould result in the uniform residual BOD. Besides, bio enzymes andother additives are added to the aeration tank, which removes thecomplex organic matter.BOD in expected : 350 mg/LBOD out desired : 35 mg/L

Tank-1 Volume : 87 cumSize : 5300mm x 4700mm x 3500mm DepthDiffusers : Fine pore diffusers.F : M : 0.1MLSS : 4000 Mg/Lit

D. AIR BLOWERS

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Type : Twin lobe compressorCapacity : 300 M3/Hr at pressure of 0.5 Kg/sq.cm

The standard air requirement (SAR) is arrived at on the basis of 2.0 Kgoxygen/Kg of BOD.

E. CLARIFIER TANK The mixed liquor (waste water with micro-organism) existing in theaeration tank has to be clarified in a clarifier tank having hopper bottom,in order to reduce the T.S.S. in the clarified water, as well as to thickenthe biomass for recirculation back to the aeration tank in order tomaintain the design MLSS (Mixed Liquor Suspended Solids)

Size : 3000mm x 3000mm x 3300mm DepthOverflow Rate : 30 Cum/sqm/DayRecirculation : 75%D.P. : 2 Hrs

F. SECONDARY AERATION TANKIn order to further removal of BOD, the sewage received from theclarifier is subjected for diffused aeration. The aeration tank is providedwith membrane type air diffusers. The main air header is connected to arotary lobe type blower, which delivers the required quantum of air tothe system. The raising bubbles from the diffusion membranes scrub thewater more efficiently causing molecular diffusion and enhance thedissolved oxygen level in the effluent. With organic matter as food andoxygen for respiration, the aerobic bacterial volume increases day byday and starts consuming the organic matter present in the water. Inorder to keep the bacterial volume high, the aerated water is decantedto separate the bacterial flock and the same is re-circulated to theaeration tank. The raising bubbles from the membrane diffusers alsokeep the content of the aeration tank in a turbulent mode therebycausing intimate mixing of bacterial volume and organic matter presentin the effluent for more uniform digestion of the organic matter. Thiswould result in the uniform residual BOD. Besides, bio enzymes andother additives are added to the aeration tank, which removes thecomplex organic matter.BOD in expected : 35 mg/LBOD out desired : 05 mg/L

Tank Volume : 28 cumSize : 2100mm x 3200mm x 3000mm Depth

+1044mm x 900mm x 3000mm Depth

Diffusers : Fine pore diffusers.F : M : 0.1MLSS : 4000 Mg/Lit

G.SECONDARY CLARIFIER TANK

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The mixed liquor (waste water with micro-organism) existing in thesecondary aeration tank has to be clarified in a secondary clarifier tankhaving hopper bottom, in order to reduce the T.S.S. in the clarifiedwater, as well as to thicken the biomass for re-circulation back to theaeration tank in order to maintain the design MLSS (Mixed LiquorSuspended Solids)

Size: Tank : 3000mm x 3000mm x 3000mm DepthOverflow Rate : 27 Cum/sqm/DayRecirculation : 75%D.P. : 2 Hrs

H.SLUDGE DISPOSAL The biomass in the aeration tank stabilizes BOD in wastewater byconsuming the organic matter in the wastewater. The metabolic activityresults in growth of the biomass population in the aeration tank.Consequently, in order to contain the level of M.L.S.S. in the aerationtank to the design level of 4000 Mg/L, it will be necessary to bleed off or

waste the excess activated sludge. For this purpose a Sludge holdingtank of 20 cum capacity has been provided with filter press fordewatering sludge.

Size : 2000mm x 2900mm x 3500mm Depth

I. CLARIFIED WATER SUMP The settled water from the settling tank is expected to meet thestandards with respect to BOD and TSS for discharge to inland surfacewaters. However it is our intention to improve the quality of treatedwater further in order to be able to re-use. For this reason, furthertreatment in the form of coagulation, filtration and disinfections isproposed. The clear water from the settling tank shall be fed to clarifiedwater tank and pumped to filters for tertiary treatment.

Tank capacity : 28 cumSize : 2000mm x 5000mm x 3000mm Depth

Filter feed pump : 39 Cum / hr at 25 M head.

J. PRESSURE SAND FILTERVertical down flow type with graded gravel / sand bed. Under drain platewith polystyrene strainers.Diameter : 1000 diaDepth of media : 1000 MM

Test Pressure : 5 Kg. / Sq.cmRate of filtration : 5 Cum /Sq.m / hr.

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K.AC FILTERSAs above but with 1000 mm GAC

L. SOFTENERVertical down flow type with resin. Under drain plate with polystyrenestrainers.

Quantity of the resin to generate zero hardness at the outlet of thesoftener.

Diameter : 1000 diaDepth of media : 1000 MM

Test Pressure : 5 Kg. / Sq.cmRate of flow : 5 Cum /Sq.m / hr.

M. CHLORINATOR100 Lit tank & 2 LPH Metering.

N.FINAL SUMP

One No. Final Sump of 110 cum capacity is also provided to holdFiltered water, before pumping to gardens and toilet flushing purpose.Online chlorination shall be done before pumping for end use.

Size : 3100mm x 3100mm x 4000mm Depth+

5300mm x 3500mm x4000mm Depth

O. PLANT PIPING AND ELECTRICAL

Plant piping shall include all pipes, fittings, valves, controllers etc.The electrical shall include a motor control center, necessary cabling,earthing etc. The equipment shall be designed to facilitate ease ofinspection, cleaning and repairs for use in installations where continuityof operation is of prime importance.

* * * * * * *

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FLOW CHART

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EQUALISATION TANK

AERATION TANK

CLARIFIER

SLUDGE PIT

Filtrate

CLARIFIED TANK

BAR SCREEN CHAMBER

TREATEDWATERTANK

TERTIARY TREATMENTPLANT

FLUSHING

IRRIGATION

Flow 110 cum/day

SECONDARY AERATION TANK

SECONDARY CLARIFIER SLUDGE FOR FURTHERDISPOSAL THROUGH

FILTER PRESS


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WATER BALANCE SHEET

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Domestic 96 Cum/day

Flushing 42 Cum/day

TOTAL 138 Cum/day

Fresh water 96 Cum/Day

From BWSSBSource

STP 110 Cum/day(After 80% diversity)

Landscape Irrigation 5Cu.m


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Subject : Solid Waste Quantities & Disposal

Sl. Description of No of Per capita Total Total

No. Module

Rooms

/Persons Considered Organic Waste

inorganic

Waste(in kg/day) (in MT/day) (in MT/day)

Office

1Population includingvisitors 2700 0.5 0.162 0.378

Total 0.5 0.162 0.378

Sl. Description of Quantity Method of Mode of

No. Waste Collection Disposal

1 InOrganic Garbage 0.378MT/Day

Manual Municipal Authority approvedagency

2 Organic Garbage 0.162MT/Day

ManualMunicipal Authority approved

agency

2 STP Sludge 4 Kg/Day Manual On Own Land for Gardening

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ANNEXURE-1

Project : Bennett Coleman & Company Limited, Times Of India CorporateOffice, Bangalore.

Sub : Water supply calculation

Type of Building Office building

Area 16,783 sqm

Total Population for 2 shifts (forOffice) 2500

Visitors 200

OfficeDomestic coldw/s lpcd

Flushing w/slpcd

45 30 15

Total population 2500 2500 2500

Water supply (A) 112500 75000 37500

15 10 5

Visitors 200 200 200

Water supply (B) 3000 2000 1000

Total (A + B) 115500 77000 38500

Domestic w/s Flushing w/s

Filter Backwash 10000 10000

Total (A + B + C) 125500 87000 38500

Add 10% for incidentals (Lts) 12550 8700 3850

Total water supply (Cum) 138.05 95.7 42.35

Say (Cum) 138 96 42

STP CAPACITY 80% OF TOTALWATER REQUIREMENT(Cum/day) 110.4

Say (Cum/day) 110

U.G SUMP Fire water storage (Cum/day) 200

Domestic Raw water tank - 1 day(Cum /day) 96

Treated water tank - 1 day(Cum/day) 96

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RE-USE OF STP TREATEDWATER

For Flushing in Cum,/day 42

For irrigation in Cum,/day 5

For HVAC in Cum,/day 63

Total in Cum/day 110

OHT

Fire water storage (Cum/day) 40

Treated water tank - Half day(Cum/day) 48

Flushing water tank - half day(Cum/day) 21

HVAC Water RequirementCum/day 63

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Feasibility Report_110 KLD