DESIGN OF WATER TREATMENT PLANT Entered Discharge Q in mld = 250.00 mld AREA REQUIREMENT OF THE PLANT
Entered Discharge Q = 250.00 mld Area requirement of the plant = 4.479 Hectares Area requirement of the plant = 44793.80 square m for the given 250.00 mld plant. DESIGN OF CASCADE AERATOR
Entered Discharge Q in mld =250.00 mld Entered Rise of each step in m [ 0.2 To 0.3 m ] = 0.25 m Entered Number of steps
[ 4 To 6 ] = 5.00 Entered Inlet Velocity in m/sec
[ 1.2 To 1.8 m/sec ] = 1.00 m/sec Number of Aerator= 2.00
Discharge of each aerator=125.00 mld
Area Requirement= 0.028 square m/cubic m/hr Inlet velocity= 1.00 m/s
Diameter of inlet pipe= 1.36 m Diameter of aerator= 14.99 m Width of each step= 1.36 m Rise of each step= 0.25 m Depth of aerator= 1.25 m
Depth of water in collecting channel= 0.92 m
Total Depth of water in collecting channel= 1.07 m
DESIGN OF RECTANGULAR CHANNEL FROM AERATOR TO PARSHALL FLUME Entered Discharge Q = 250.00 mld
Entered length of rectangular channel in m = 40.00 m Entered velocity of rectangular channel in m/s
[ 1 To 1.8 m/s ] = 1.00 m/s Number of Rectangular channel= 2.00
Discharge of each Rectangular channel=125.00 mld Length of Rectangular channel= 40.00 m
Velocity of Rectangular channel= 1.00 m/s Depth of Rectangular channel= 0.96 m
Total Depth of Rectangular channel= 1.11 m Width of Rectangular channel= 1.50 m
Slope of Rectangular channel= 1 : 1862
DESIGN OF PARSHALL FLUME
Entered Discharge Q = 250.00 mld Number of Parshall flume= 2.00
Discharge of each Parshall flume=125.00 mld
Total depth of flow in upstream leg of the flume at one third point= 1.86 m Throat width of the flume(W)= 300 mm
Throat length of the flume(F)= 600 mm Width at diverging end(C)= 600 mm Width at converging end(DF)= 831 mm Length of diverging part(G)= 900 mm Length of converging part(B)=1322 mm
DESIGN OF DISTRIBUTION CHAMBER BEFORE FLASH MIXER
Entered Discharge Q = 250.00 mld Entered depth of distribution chamber in m
[ 2 To 3.5 m ] = 3.00 m Number of distribution chamber= 2.00
Discharge of each distribution chamber=125.000 mld Number of rapid mix unit= 4.00
Discharge of each rapid mix unit= 62.500 mld Diameter of distribution chamber= 6.07 m Depth of distribution chamber= 3.0 m
Total Depth of distribution chamber= 3.5 m DESIGN OF RAPID MIX UNIT
Entered Discharge Q = 250.00 mld Entered Detention time in sec
[ 20 To 60 sec ] = 40.00 m/s Entered Inlet Velocity in m/s
[ 0.9 To 1.8 m/s ] = 1.00 m/s Entered Outlet Velocity in m/s
[ 0.6 To 1.8 m/s ] = 0.90 m/s Entered Number of blades
[ 2 To 6 ] = 4.00 Number of Rapid mix unit= 4.00
Discharge of each Rapid mix unit= 62.500 mld Ratio of Tank height to diameter= 1.50 Detention Time of Tank= 40.00 sec
Diameter of Tank= 2.91 m Height of Tank= 4.36 m
Total Height of Tank= 4.56 m Power Spent= 5911.00 watts
Power per unit Volume=205.00 watts per cubic m
Power per unit flow of water= 2.27 watts per cubic m per hr
Diameter of Impeller= 1.16 m Radius of Impeller= 0.58 m
Rotational speed of Impeller=100.00 rpm Velocity at the tip of the Blade= 6.09 m/s
Relative Velocity of Blade= 4.56 m/s Number of Blades= 4
Width of each Blade= 0.05 m Depth of each Blade= 0.35 m Diameter of Inlet Pipe= 0.96 m Diameter of Outlet Pipe= 1.01 m
DESIGN OF DISTRIBUTION CHAMBER BEFORE CLARIFLOCCULATOR
Entered Discharge Q = 250.00 mld Entered depth of distribution chamber in m
[ 2 To 3 m ] = 3.00 m Number of distribution chamber= 4.00
Discharge of each distribution chamber= 62.500 mld Number of clariflocculator = 8.00
Discharge of each clariflocculator= 31.250 mld Diameter of each distribution chamber= 4.29 m Depth of each distribution chamber= 3.0 m
Total Depth of each distribution chamber= 3.5 m DESIGN OF CLARIFLOCCULATOR
Entered Discharge Q = 250.00 mld Entered Velocity of flow through inlet pipe in m/s [ 1 To 1.5 m/s ] = 1.00 m/s Entered Velocity through ports in m/s
[ 0.2 To 0.8 m/s ] = 0.50 m/s Entered Detention Time of Flocculation Basin in min
[ 20 To 40 min ] = 30.00 min Entered Depth of Flocculation Basin in m
[ 3 To 4.5 m ] = 4.50 m Entered Number of blades
[ 4 To 12 ] = 8.00 Number of clariflocculator= 8.00
Discharge of each clariflocculator= 31.25 mld Gt Factor=39600.00
Velocity Gradient of flocculator= 22.00 (1/sec) Detention Time of flocculator= 30.00 min
Detention Time of Clarifier= 3.10 hr Diameter of inlet pipe= 0.68 m
Number of ports=38.00 of size 0.1 m by 0.2 m Diameter of flocculator=14.25 m
Diameter of circular clarifier= 36.69 m Power spent=281.00 watts
Number of blades= 8.00 Depth of each blade= 3.00 m Width of each blade= 0.48 m
Area ratio= 18.93 Percent Hence Ok Rotational speed of paddle= 4.00 rpm Radius of shaft= 0.96 m
between flocculator & clarifier= 0.30 m/min Total Depth of clarifier= 5.25 m
Depth at the centre of clariflocculator= 6.78 m Surface Loading= 1.45 cubic m/square m/hr Hence Ok Weir Loading=271.28 cubic m/m/day Hence Ok
Number of notches= 1112
Center to Center distance of v-notches= 0.10 m Depth of water in collecting channel= 0.30 m
Total Depth of water in collecting channel= 0.60 m
Size of collecting channel(with flat bottom)=0.8 m by 0.60 m
DESIGN OF RAPID SAND FILTER Entered Discharge Q = 250.00 mld Enter Rate of filtration in cu. m/sq. m/hr
[ Range 4.8 to 6.0 ] = 5.00 Enter length to width ratio of filter bed
[ Range 1.11 to 1.66 ] = 1.40 Enter ratio of c/s area of lateral to area of orifices [ Range 2 to 4 ] = 3.00 Enter ratio of area of manifold to area of laterals [ Range 1.5 to 3 ] = 2.00 Enter quantity of air required for backwash
[ Range 0.9 to 1.5 cubic m/sq. m/min ] = 1.20 Total depth of sand bed=0.60 m
Depth of Gravel layer for gravel size 2 mm - 5 mm = 7 cm Depth of Gravel layer for gravel size 5 mm - 12 mm = 8 cm Depth of Gravel layer for gravel size 12 mm - 20 mm = 9 cm Depth of Gravel layer for gravel size 20 mm - 38 mm = 13 cm Depth of Gravel layer for gravel size 38 mm - 65 mm = 15 cm Total depth of gravel bed= 0.53 m
Number of filter beds= 31 Width of filter bed= 7.14 m Length of filter bed= 10.00 m Water depth over sand bed= 1.20 m
Total number of perforations required= 2730 Diameter of central manifold= 1.28 m
Number of laterals= 133 Diameter of lateral= 78 mm
Number of perforations per lateral= 20 Length of each lateral= 2.93 m
Diameter of orifices=10 mm
Spacing of perforations per lateral= 143 mm Spacing of wash water trough= 1.25 m
Provide 8 troughs of 30 cm wide by 46 cm deep in each filter Provide main trough of 45 cm wide by 135 cm deep in each filter Quantity of air required=428.57 cubic m
Provide 2 number of wash water tank Diameter of wash water tank= 18.10 m
Height of wash water tank= 3.00 m
DESIGN OF PURE WATER SUMP
Entered Discharge Q = 250.00 mld Number of pure water sump = 3
Discharge of each sump= 83.33 mld Sump size= 38 m x 38 m Depth of sump= 4.00 m
CHEMICAL STORAGE HOUSE
Entered Discharge Q = 250.00 mld Number of chemical storage house= 3
Discharge of each chemical storage house= 83.33 mld One bag contains 50 kg of Alum
Provide Number of bags of Alum=15000 for three months for one chemical storage house Provide 14 rooms of 7.50 m X 7.50 m
for one chemical storage house ALUM SOLUTION TANK
Entered Discharge Q = 250.00 mld Provide 40.00 tanks of 1.5 m x 1.5 m x 1.2 m deep
DESIGN OF CHLORINATOR
Entered Discharge Q = 250.00 mld One Cylinder contains 100 kg of chlorine.
Provide 151.00 number of cylinders per month. HYDRAULIC PROFILE OF WTP Entered Discharge = 250.00 mld
Entered length of pipe from parshall flume to distribution chamber in m = 10 .00
Entered length of pipe from distribution chamber to flash mixer in m = 30.00 Entered length of pipe from flash mixer to distribution chamber in m = 5.00 Enter length of pipe from distribution chamber to clariflocculator in m = 30 .00
Entered length of pipe from clariflocculator to filter in m = 40.00 Entered length of pipe from filter to pure water sump in m = 30.00 Entered velocity of flow through pipe from
parshall flume to distribution chamber [ 0.9 To 1.8 m/s ] = 1.00
Entered velocity of flow through pipe from clariflocculator to filter [ 0.9 To 1.8 m/s ] = 1.00
Entered velocity of flow through pipe from filter to pure water sump [ 0.9 To 1.8 m/s ] = 1.00
Entered R.L. of tip of aeration fountain in m =216.00 Entered number of bent of pipe from
parshall flume to distribution chamber = 2.00 Entered number of bent of pipe from
distribution chamber to flash mixer = 2.00 Entered number of bent of pipe from
flash mixer to distribution chamber = 2.00 Entered number of bent of pipe from
distribution chamber to clariflocculator = 2.00 Entered number of bent of pipe from clariflocculator to filter = 1.00 Entered number of bent of pipe from filter to pure water sump = 1.00 FRICTION FACTOR
PIPE MATERIAL FRICTION FACTOR R.C.C.,A.C.,HDPE/PVC,SGSW 0.010 - 0.020 C.I.(for corrosive waters) 0.030 - 0.053 C.I.(for non-corrosive waters) 0.034 - 0.070 G.I. 0.031 - 0.060 Entered friction factor = 0.04
R.L. of tip of aeration fountain=216.000 m R.L. of second cascade=215.750 m
R.L. of third cascade=215.500 m R.L. of fourth cascade=215.250 m R.L. of fifth cascade=215.000 m
Water level of collecting channel=214.850 m Base level of collecting channel=213.934 m
Water level of distribution chamber before flash mixer=214.468 m Water level of flash mixer=214.295 m
Water level of distribution chamber before clariflocculator=214.192 m Water level of clariflocculator=213.626 m
Water level of collecting channel of clariflocculator=213.426 m Water level in the filter=213.094 m
Water level in clear water sump=211.888 m
