Process Design Calculation3- ND

7/23/2019 Process Design Calculation3- ND

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Consultancy for New WTP, Recycling Plant Augmentation and Automation of Existing WTP at Wadgaon, Pune

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1 Design Considerations

Desired Output Q(out) 250000.00 m /day

Internal loss after considering

recovery IL @ 3 % 7500.00 m3/day

Raw water Input Q(in) = Q(out) + IL 257500.00 m /day

Working Hours t 22.00 Hours/day

Average Flow Rate (Normal) Q(avg) 11704.55 m /Hour

Overload flow for hydraulic design

of inlet works 30.00 %

Overload flow for hydraulic design

rest of the plant 25.00 %

Inlet Works Average Flow Rate 11704.55 m3

/hour Inlet Works Average Flow Rate

(Overload) Q(OL) 30 % over nornmal flow 15215.91 m3/hour

n et wor s verage ow ate

(Normal) Q(avg) 3.25 m3/Sec

Inlet works Average Flow Rate

(Overload) Q(OL) 30 % over nornmal flow 4.23 m3/Sec

2 Treatment Plant Units

2.1 Inlet Chamber

Design Nominal Flow 300000.00 m3/day

Desigin input flow 309000.00 m3/day

Inlet Works Average Flow Rate 14045.45 m3/hour n et or s verage ow ate

(Overload) Q(OL) 30 % over nornmal flow 18259.09 m3/hour

Inlet works Average Flow Rate

(Normal) Q(avg) 3.90 m3/Sec

n et wor s verage ow ate

(Overload) Q(OL) 30 % over nornmal flow 5.07 m3/Sec

Design flow Present normal 3.25 m3/Sec

No of units N 1.00 No

Hydraulic Retention Time HRT 60.00 Sec @ avg flow

Volume V = Q(avg) X HRT 234.09 m

Depth D 5.15 m

Area A = V/ D 45.45 m2

Diameter 7.61 m

Check for HRT at Design Ultimate

Overload Condition 46.15 Sec

Dimensions Adopted

Diameter 7.61 m

Nagaur Lif t Water Supply Project

250 MLD CAPACITY WTP AT NOKHA DAIYYA (300 MLD Ult imate)

Design Calculations for Main Units




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Depth 5.15 m

Free Board 0.50 m

Construction RCC

Protection Food Grade Epoxy on all internal

2.3 Inlet Channel

No of Units N 1.00 No

Design Flow Normal Ultimate 250 + 50 MLD 3.90 m3/Sec

Design Flow Overload Ultimate 5.07 m3/Sec

Design flow Present normal Q(avg) 3.25 m /Sec

Flow present Overload Q(OL) 4.23 m /Sec

Velocity V 0.80 m/sec

rea requre or t mate ormacondition A= Q(Uliti_avg)/V 4.88 m2

Width W 2.50 m

Depth D 1.95 m

Check for Velocity at Ultimate

overload condition 1.04 m/sec

Check for Velocity at present

overload condition 0.87 m/sec

Dimensions Adopted

Length 5.00 m

Width 2.50 m

Liquid Depth 1.95 m

FB 0.50 m

2.4 Parshall Flume

Approach Channel Width W 2.50 m

Design flow Max Q(OL) 5.07 m /Sec

Design flow min Q(avg) 3.25 m /Sec

Throat Width 1.5 m

Head at max. flow condition Q = 2.264WH3/2

1.307 m

Head at min. flow condition 0.971 m

Headd Loss at Max Flow 0.784 m

Head Loss at Min flow 0.583 m

Water Level D/s of Flume at Max Flow 0.523 m

Water Depth at D/s of Flume at Min Flow 0.261 m

2.5 Distribution Box

No of Inlet 1 No

No of Outlet 6 No

HRT in the inlet box 60 Sec




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Inflow 3.90 m3/Sec

Vol 234.09 m

3

Weir length for distribution 5.00 m

Maximum Flow through each weir 0.85 m3/Sec

Rise Over Weir 0.2 m

No of Outlet on one side 3 No

Length of Distribution Box 15 m

Depth 3.5 m

Area 66.88 m2

Width 4.46

2.4 Flash Mixer

No of Units N 6.00 m

Flow (avg)Q

(avg) 3.90m /sec

Flow through each unit Q(unit)=Q(avg)/N 0.65 m /Sec

HRT t 60.00 sec

Volume of each tank V 39.02 m3

Liquid depth 3.25 m

Area of cross section A 12.00 m2

Length L 3.46 m

Width W 3.46 m

Dimensions Adopted

Length 3.50 m

Width 3.50 m

Liquid Depth 3.25 mFree Board 0.50 m

Tank Volume 39.81 m3

Construction RCC

2.5 Pipe Connection From Flash Mixer to Flocculation Cum Settling Tank

No of Connections 6.00 No

Flow Normal Q(avg) 3.90 m /Sec

Flow Overload 5.07 m3/Sec

Velocity 0.90 m/sec

Area required for overload condition 0.94 m2

Diameter of Pipe 1.09 m

Pipe Size Provided 1000.00 mmCheck Velocity for Overload condition

2.6 Flocculation cum settling Tank (Conventional Design)

No Of Units N 6 All Working

Design Flow Q(avg) 309000.00 m /day

Flow through each tank (Avg) 51500.00 m3/day

Inner diameter of Central Coloum 1.00 m




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Outer Dia of Central Coloum 1.30 m

HRT in flocculation tank 25.00 min

Volume of flocculation Zone 894.10 m3/day

Add for Vol occupied by central coloum 3.98 m3/day

Corrected Volume of Flocculation Zone 898.08 m3

Depth of flocculation Zone 3.00 m

Area of flocculation Zone 299.36 m2

Inner Diameter of Flocculation Zone 19.53 m

Outer Diameter of Flocculation Zone 19.93 m

Outer surface Area of Flocculation Zone 311.75 m2

Surface Loading Rate in clarifier 35.00 m /m /day

Surface Area Required 1783.18 m2

Diameter Of Unit 47.66 m

Detention Time HRT 2.50 Hours at Avg flow

Volume Required 5364.58 m3

Depth required SWD= V / SA 3.01 m

Domensions Adopted

Flocculation Zone

Diameter 19.53 m

Depth 3.00 m

Overall Clarifier & Flocculator

Diameter 48.00 m

SWD 3.01 m

FB 0.50 m

Check for Weir loading

Length of weir 150.72 m

Loading 341.69 m3/m/day

Launder Dimensions

Flow 0.33 m3/Sec

Velocity 0.90 m/sec

Area 0.36 m2

Depth 0.50 M

Width 0.72 M

2.7 Sludge Outlets from Clariflocculator

No of Connections 6.00 No

Discharge Volume 7725.00 m3/day

Discharge Volume /outlet 1287.50 m3/day

Discharge Duration 150.00 Min

Flow rate 0.14 m3/Sec

Velocity 1.50 m/sec

Area required 0.10 m2




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Pipe Size Provided 350.00 mm

2.8 Telescopic Device for constant discharge

Diameter 250.00 mm

2.1 Channel from clarifloccultor to Common Channel

No of Units 2.00 No



Velocity 1.00 m/sec


Width 1.60 m

Depth 1.52 m

2.11 Filter Inlet Channel

No of Units 2.00 No

Flow Normal 1.95 m3/Sec


Velocity 1.00 m/sec


Width 0.60 m

Depth 1.95 m

2.12 Filtration units

No of Filter House 1 Building

Flow to Each 14045 m3/hour

No of Total Filter Box 24 m

No of Working Unit at a time 22 m

Working time for each filter WT 22.00 Hours

Design Flow (Average) Q(desavg) = Q(avg)/22 14045.45 m3/hour

Design Flow Per Filter (avg) q(avg) = Q(desavg)/ No of Filter 638.43 m3/hour

Filtration Rate FR 7.50 m3/m

2/day

Area required FA 85.12 m2

L/B 1.50 mshort side of filter Width 7.53 m

Long Side Length 11.30 m

Washwater Gutter width 0.90 m

Flow when one filter is out 668.83 m3/hour

Filtration rate 7.86 m3/m

2/day

Overall fil ter house diamnsions

Width 8.43 m




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Length 11.30 m

Ht 3.50 m

Two Filter Houses, each having Two rows of Eight fil ters each and midd le operating gallery consi

Dimensions of Filter House

No of Filters in each filt er house 24.00 No

Over all length 107.40 m

Overall Wid th 33.30 m

Operating gallery 7.50 m

2.13 Sizes of the Ports

a Filter Inlet

No of Working Inlets 22.00 No



Velocity 1.00 m/sec



Inlet Size Provided 500 mm

b Filter Water Outlet

No of Working Outlets 22.00 No



Velocity 1.00 m/sec


Diameter of Opening 0.52 m

Inlet Size Provided 500.00 mm

c Back Wash Water Inlet

Back Wash Rate 30.00 m3/m

2/hour

Area of Filter Bed 85.12 m2

No of Inlets in each Filter 1.00 m

Wash Water Flow through each inlet 2553.72 m3/hour

Wash Water Flow through each inlet 0.71 m3/Sec

Velocity 2.50 m/sec

Area required 0.28 Sq. M


Inlet Size Provided 600.00 mm

d Wash Water Outlet

No of Outlets 1.00 No


Velocity 2.50 m/sec





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Diameter of Opening 0.60 m

Outlet Size Provided 600.00 mm

2.14 Filter Outlet Channel

No of Units 1.00 No

Flow Normal 14045.45 m3/hour

Flow Overload 16854.55 m3/hour

Flow 4.68 m3/Sec

Velocity 1.00 m/sec


Width 2.00 m

Depth 2.34 m

FB 0.30 m

2.15 Washwater Outlet Channel

No of Units 1.00 No

Flow Normal 0.71 m3/hour

Velocity 1.00 m/sec


Width 0.80 m

Depth 0.89 m

Free Board 0.50 m

2.16 Pipe Connection from Filter Outlet Channel to CCT (Alternative to Channel)

No of Pipes 1.00 No



Velocity 1.20 m/sec


Dimeter of pipe 2.28 m

Provide 2200.00 mm

2.17 Chlorine Contact Tank

No of Units N 1 No

Compartments n 4 No

Design Flow Q(avg) 14045.45 m /hour

HRT T 20.00 mVolume V=(Q/60) X HRT 4681.82 cu.m

Depth D 4.00 m

Surface Area A = V/D 1170.45 m2

Width 42.00 m

Partition Wall Thickness Wt 0.25 m

No of walls NWALLS 3.00 No

Corrected Width W = A 43.00 m




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Length 27.87 m

Free Board 0.50 m

Overall Height 4.50 m

Size of Each Compartment

Width 9.75 m

Length 27.87 m

Dimensions Adopted

No of Compartments 4.00 No

Width 9.75 m

Length 27.87 m

Liquid Depth 4.00 m

Free Board 0.50 m

Construction RCC

3 Equipment3.1 Filter backwash Pumps

Back wash Water requirement

Backwash rate 25.00 m3/m

2/hour

Backwash Flow 2128.10 m3/hour

Backwash Duration 10.00 Min

Water Consumed /back wash 354.68 m3

No of Back wash /hour 1.00 Provision

Overhead Tank Capacity 354.68 m3

No of Tank 1.00 No

Capacity of Each 354.68 m3

Provide 465.00 m3

Punps for filling backwash Tank 2.00 No

Working 1.00 No

Standby 1.00 No

Pump Capacity 930.00 m3/hour

Head 15.00 m

3.2 Air Blowers

No of Units/filter House 3.00 No

No of Working units 2.00 No

Total No 3.00 Two Working

Air Scour Rate Air rate 55.00 m3/m

2/hour

Area of filter A 85.12 m2

Air Requirement Airqty =Air Rate x Area 4681.82 m3/hour

discharge head 4.50 MWC

Capacity of each blower to be provide 2340.91 m3/hour

3.3 Chlorinators for pre chlorinations

Chlorine Dose = 2 mg/l

Flow = 14045.5 m3/h




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Maximum Chlorine Dosing rate = 28.1 kg/h

Cosider capacity of each

chlorinator as = 30.00 kg/h

So No of units,

Working = 1.0 No

standby = 1.0 No

Maximum withdrawal capacity of

each tonner = kg/h

Tonner for each Chorinator = 2 No

Total tonners required including

standby = 4 NoTotal tonners required

including standby with

changeover = 8.00 No

3.4 Chlorinators for post chlorinations

Chlorine Dose = 2 mg/l

Flow = 14045.5 m3/h

Maximum Chlorine Dosing rate = 28.1 kg/hCosider capacity of each


So No of units,

Working = 2 No

(Cosidering 50 % standby) = 1 No


each tonner = kg/h

Tonner for each Chorinator = 2 NoTotal tonners required including

standby = 6 NoTotal tonners required

including standby with

changeover = 12.00 No

3.5 Chlorinators fo r Water Recovery and Recycling

Chlorine Dose = 5.0 mg/l

Flow = 625.0 m3/h

Maximum Chlorine Dosing rate = 3.1 kg/h

Cosider capacity of each


So No of units,

Working = 1 No

standby = 1 No


each tonner = 4 kg/h

Tonner for each Chorinator = 1 nos




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Design Calculations for Main UnitsTotal tonners required including

standby = 2 No


each tonner = 7 kg/h

Tonner for each Chorinator = 1 nosTotal tonners required including

standby = 2

3.6 Total chlorine requirement

Total chlorine requirement = 59.3 kg/h

= 1423.4 kg/d

Capacity per cylinder = 900 kg

Nos. of cylinders = 1.6 per day

Nos. of cylinders = 33 per 21 days

4 Chlorine Drum Store And Chlorinator Room

4.1 Store

No of Drums Connected for Pre Chlorination 4.00 No

No of Drums Connected for Post Chlorination 4.00 No

No of Drums Connected for Dirty backwash treatment 2.00 No

Extra Filled Drum 13.00 No

Extra Empty Drum 9.00 No

Total Drums 32.00 No

Provide space for 36.00 No

No of Rows 9.00 No

Width 15.36 m

Length 15.78 m

4.2 Chlorinator Room

Width 15.78 m

Length 7.00 m

4.3 Drum Pit

Length 2.00 m

Width 2.00 m

Depth 2.00 m

5 Dirty Backwash Water Recovery System

5.1 Sump for clariflocculator Sludge

Wastewater from clarifier 7725.00 m3/day

Discharge frequency 3.00 Hours

No of discharges 8.00 per day




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Duration of each discharge 10.00 Min

Total discharge time 80.00 min

Flow rate 1.61 m3/Sec

Retention time in collection tank 1.00 discharge

Volume of the tank 965.63 m3

Depth of tank 3.00 m

Area 321.88 m2

Length 25.37 m

Width 12.69 m

5.2 Thickener for clariflocculator Sludge

Plant Capacity 309000.00 Cu. M. /day

Flow for Phase 1 14045.45 Cu. M. /hr

SS Concentration in raw effluent 15.00 mg/l

Total Solid Load because of SS 5056.36 kg/day

Alum Consumption as Al2O3 772.50 kg/day

Sludge Formed 1605.59 kg/day

Total Solid Load 6661.95 kg/day

Solid separated in clariflocculator 99.00 %

Solids going to thickener 6328.85 Kg/day

Design Flow Rate for Thickener 321.88 Cu. M. /hr

Solid Loading Rate 40.00 kg/m2/day

Surface Loading Rate 40.00 m3/m

2/day

Area required for Soild Loading Criteria 158.22 m2

Area required for Surface Loading Criteria 193.13 m

2

Adopted Area 193.13 m2

Diameter 15.68 m

Outlet Sludge Conc 5.00 %

Thickened Sludge Volume 154.50 m3/day

5.3 Sump for filter backwash

Filter Back wash 0.71 m3/Sec

Duration 10.00 Min

Total Flow 425.62 m3

Back wash Flow for 2 filter 851.24 m3

Volume required 851.24 m3

Depth 3.20 m

Area 266.01 m3/hour

Width 23.06 m

Length 11.53 m

Dimensions Adopted

Length 25.37 m

Width 12.69 m




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F. B. 0.50 m

5.4 Clarifier for Filter Backwash recycling

Flow 425.62 Cu.M/hour

10214.88 Cu. M/day

Surface Loading Rate 100.00 kg/m2/day


Diameter 11.41 m

SWD 2.00 m

Pipe Size from Dirty Back wash Transfer Pumps to Clarifier

Flow 425.62 m3/Sec

Velocity 1.50 m/sec


Diameter of Header Pipe 19.01 m

Provide Pipe dia 500.00 MM

5.5 Sludge Drying Beds

Volume of Thickened Sludge 154.50 m3/day

Drying Cycle 15.00 Days

Volume for 11 days 2317.50 m3

Application depth 0.80 m


No of beds 14.00

Area of each 206.92 m2

Length 17.00

12.17

Dimensions adopted

Langth 17.00 m

Width 12.00 m

Depth 1.70 m

6 Calculations for Chemical Dosing

6.1 Dosing Tanks

Design Flow Normal Ultimate 250+50MLD+losses 9 MLD 309.00 MLD

309000.00 m3/day

Dose of Aluminium Sulphate as Al2O3 (Average) 2.50 mg/l

Cosumption As Al2O3 772.5 Kg/day




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Al2O3 Contents in commercial product 17.0 %

Quantity of commercial product required 4544.1 Kg/day Alum Consumption 206.55 Kg/hour

Solution Tank Capacity 8.00 Hours

Cosumptiion of Alum in 8 hours 1652.41 Kg

Solution Strength 5 % W/V

Solution Volume for 8 hours 33048.13 lit

No of Working Tanks 1 No

Volume of Each 33.05 Cu. M

No of Standby tank 2 No

Volume of Each 33.05 m3

Depth 2.50 m

Area Required 13.22 m2

Width 3.64 m

Langth 3.64 m

Dimension Adopted

Length 3.64 mwidth 3.64 m

Depth 2.50 m

FB 0.50 m

6.2 Space Requirement For storing Alum

Flow 309000.0 m3/day

Dose of Aluminium Sulphate as Al2O3 (Average) 2.5 PPM

Cosumption As Al2O

3772.5 Kg/day


Quantity of commercial product required 4544.1 Kg/day

For 45 days 204485.3 kg

Wt of brick 20.0 Kg

No of Bricks 10224.3 No

Vol of Brick 0.0 m3

Volume Required 184.0 m3

Ht of Stack 1.8 m


Acess Area 25.0 %


Void space 15.0 %Correct Area for Void Space 147.0 m

2

Provide 150.0 m2

Calculation For PAC

6.3 PAC

Calculation for Storage




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Treatment plant capacity (ultimate) 309000.00 m3/day

Dose of PAC as Al2O3 (Average)2.50 mg/l

Cosumption As Al2O3 772.50 Kg/day


Consumption in terms of commercial product 8583.33 Kg/day

Spcific Gavity of Solution 1.21Cosumption of commercial product on volumetric basis 7093.66 Lit/day

45 Days requirement 319214.88 Lits

319.21 m3

No of Storage Tanks 2.00

Volume of Each Tank 159.61 m3

Tank Dimensions

Depth 2.50 M

Area 63.84

Length 7.99

Width 7.99

6.4 Alternate Design with HDPE Tank

Capacity of Tanks 20000.00 Lit

No of Tanks required 15.96

Provide 16.00 Tanks

6.5 Dosing Solution Tank

Daily Consumption 7093.66 Lit/day

No of working Tanks 1.00No of Standby Tank 2.00

Volume of Each Tank 7093.66 Lit

Say 7500.00 Lit

Depth 1.50 M

Area 5.00 m

Length 2.24 m

Width 2.24

Dimension Adopted

Length 2.24 mwidth 2.24 m

Depth 1.50 mFB 0.50 m

Process Design Calculation3- ND

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