1 Turbidity = NTU 2 ph = Alkalinity = 34 mg/l as CaCO 3 4 Temperature = 5 Fe = 2 mg/l 6 Mn = mg/l 7 Total Hardness = 50mg/l as CaCO 3

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3 DESIGN CALIFIER TANK (SLUDGE BLANKET CLARIFIER TYPE : SLUDGE RECIRCULATION) 1. Flow Rate Q 150 m 3 /hr. Raw Water Quality input 1 Turbidity NTU ph Alkalinity 3 mg/l as CaCO 3 Temperature 5 Fe mg/l 6 Mn mg/l 7 Total Hardness 50mg/l as CaCO 3 o C 0:3/7//007 1/1 Design Clarifier Tank(Solid Contact)/Design Flow

4 3. Design Criteria 3.1. Kawamura Flocculation Time approximate 0 min normal 0-0 min 3.1. Settling Time 1 - hr Surface Loading - 3 m/hr 3.1. Weir Loading m 3 /hr Upflow Velocity < 10 mm/min Slurry Circulation rate up to 3-5 time the raw water inflow rate G s MAXIMUM MIXER TIP SPEED 0.9 m/s (Baffled Channel) 0.9 m/s (Horizontal Shaft with Paddles) m/s (Vertical Shaft with Paddles) Equation mixer tip speed π DN Free Board is approximate 0.6 m Water Depth - 5 m Length and Width ratio 6 : 1 (minimum : 1) (Rectangular Basin) Width and Water Depth 3 : 1 (maximum 6 : 1) (Rectangular Basin) Blade area/rapid Mixing Tank area % (page 11) Blade : Diameter Blade/Diameter Mixing Tank (page 11) Shaft rpm Q, Sim 3..1 Detention Time Hr Surface Loading - m/hr 3..3 Weir Loading 7.1 m 3 /m.hr 3.3. Sheet Master Degree of Environmental Engineering 1:0/7//007 1/3 Design Clarifier Tank(Solid Contact)/Design Criteria

5 3.3.1 Weir Loading 7.1 m 3 /m.hr 3.3. Surface Loading - Q < 0.35 m 3 /min m/hr - Q > 0.35 m 3 /min m/hr Water Depth 3-5 m Paddle radius 65-75% of radius for Flocculator Detention Time 1-3 Hr Diameter Tank < 5 m Paddle at bottom tank high bottom cm Paddle Velocity - 3 rpm Effective Paddle Area 10 % Sweep area of the fllocculator 3.. Water Work Engineering Book 3..1 Flocculation..1.1 Detention Time 0-60 min..1. Velocity Gradient S GT 1x10-15x Periperal Velocity of Paddle m/s..1.5 Shaft rotation speed rpm 3.. Sedimetation (Coagulation)...1 Detention Time - 8 hr... Surface Loading 0-0 m 3 /m.day...3 Weir Loading m 3 /m.day 3..3 Sedimentation (Softening)..3.1 Detention Time 1-6 Hr..3. Surface Loading 0-60 m 3 /m.day..3.3 Weir Loading m 3 /m.day 3.5 Clarifier Design (Water Poluttion Control Federation 1985) 1:0/7//007 /3 Design Clarifier Tank(Solid Contact)/Design Criteria

6 3.5.1 Detention Time Flocculator central well 0-30 min 3.5. Weir Loading (outlet) 100 to 150 m 3 /m.day Radial inner feed well 10 to 13% of the tank radius 3.5. velocity gradient S -1 1:0/7//007 3/3 Design Clarifier Tank(Solid Contact)/Design Criteria

7 GiveContact Time in Hopper inside (Flocculation Zone) 0 min Contact Time ZONE 1 0 min (Criteria 0-30 min) Contact Time outside (ZONE + ZONE 3) + ZONE 0 min 5 Flow Rate 150 m 3 /hr 6 Volume in inside Hopper Q x t 100 m 3 7 Give Detention Time in outside Hopper(Sedimentation Zone) 1.7 Hr 8 Volume in outside Hopper Q x t 55 m 3 9 Calculation Diameter Hopper inside 9. ZONE 1 (Circular Basin) Volume in ZONE 1 Q x t Volume in ZONE 1 50 m 3 Give D1 m Surface Area m A 1 πd m Depth in ZONE m 9. ZONE (Circular Basin) Give D 5 m Surface Area m πd A m Depth in ZONE m (safety 0.5 m) Volume ZONE m ZONE 3 (Conical Basin) Give D3 7 m Give Depth in ZONE 3 1 m 0:/7//007 1/ Design Clarifier Tank(Solid Contact)/Hopper inside&outside

8 Surface area on Top πd Surface area on Top (A3) m Surface area on Bottom πd Surface area on Bottom (A) m d Volume x ( A 1 + A + A 1 xa 6 Volume ZONE m 3 ) 9. Outside Volume ZONE andzone 3 Volume ZONE + ZONE 3 - Volume ZONE m ZONE (Circular Basin) Volume in ZONE Total Volume in Hopper inside id - (Volume ZONE+ ZONE3) Volume in ZONE.3331 m 3 Depth in ZONE Volume Zone π D x m Check Detention Time Outside ZONE and ZONE3 + ZONE hr 0 min Water Depth m (Design Criteria 3-5 m,kawamura,page161) Free Board from Design Criteria 0.6 m (Kawamura) Solid Contact Clarifier Tank Height m 0:/7//007 / Design Clarifier Tank(Solid Contact)/Hopper inside&outside

9 10 Calculation Diameter Solid Contact Clarifier Total Volume Volume inside Hopper + Volume outside Hopper 355 m 3 Diameter Solid Contact Clarifier xvolume π xwater depth m 0:/7//007 3/ Design Clarifier Tank(Solid Contact)/Hopper inside&outside

10 D ZONE Depth ZONE ZONE1 D1 ZONE3 Depth ZONE 3 ZONE Depth ZONE D3 0:/7//007 / Design Clarifier Tank(Solid Contact)/Hopper inside&outside

11 Page 1 of 1 Impellers Mixer Shape of Impeller

12 1. Rapid Mixing by Radial and Axial Impellers Page 1 of 3 G P μ V Where : G P Velocity gradient, sec -1 (G 700 to 1000 sec -1 ) Power Imparted to the water, N-m/s or Watt or kg.m /s 3 V Volume of the basin, m 3 μ absolute viscosity of the fluid, N-s/m The motor power of the mixer is the power to drive the speed reduction gears. The powe imparted to the water by a mixer is calculated from P πnt Where : n T Impeller speed, revolutions per second (rps) Impeller shaft torque, N-m. Other expression for the power imparted to the water are given by : P N n d 3 is used for the Laminar-flow range (Reynolds number N R < 10) P N pμ n 3 d 5 P ρ is used for the Turbulent-flow range (Reynolds number NR > 10,000) Where : N P d ρ Power number of the impeller (power numbers for different types of impellers are give in table 8-5 impeller diameter, m mass density of fluid, kg/m 3 Design Clarifier Tank(Solid Contact) Equation

13 μ Page of 3 absolute viscosity of water, N-s/m The Reynolds number for Rapid mixers is given by : N R d nρ μ The velocity gradient for a mixing basin utilizing flow - induced turbulence can be calculated from : Where : G h L t g ρ h t μ L total head loss through the mixer,m detention time, s Detention time in Rapid-Mix Basin t V Q Where : t average detention time, min Q flow rate, m 3 /min V volume of the tank, m 3 Check Mixer Tip Speed Where : Tip Speed π Dn D n m/s Diameter of Impeller (m.) Impeller speed, revolutions per second (rps) Design Clarifier Tank(Solid Contact) Equation

14 Page 3 of 3 Rapid Mix Tip Speed > 1 m/s Slow Mix 1.Baffle Channel < 0.9 m/s.mechanical Flocculators - Horozontal Shaft with Paddle < 0.9 m/s - Vertical Shaft with Blade < 1.8 m/s to.7 m/s Design Clarifier Tank(Solid Contact) Equation

15 Page 1 of 1 1. Power Number for Impeller. Coefficient of Drag for Paddle Design Clarifier Tank(Solid Contact) Power Number

16 Page 1 of 5 Impeller Mixing Give 1 Flow rates 150 m 3 /hr Volume of the ZONE m 3 μ ρ Kg/m.s at 5 o C Kg/m 3 at 5 o C G P μv Where : G Velocity gradient, sec -1 P Power Imparted to the water, N-m/s or Watt or kg.m /s 3 V Volume of the basin, m 3 μ absolute viscosity of the fluid, N-s/m Give Velocity Gradient (G) 70 s -1 (Design Criteria Kawamora) 3 Power Imparted to the water, P 19.3 N-m/s or Watt or kg.m /s kwatt P is the power imparted to the water. The power of the driver(p') is calculated by diving P by the efficiency of the gearbox, which is typically around 80 percent Power Imparted to the water, P' 0.71 kwatt 1 HP kwatt Power Imparted to the water, P' HP Use Standard motor of P' HP, rpm and efficiency 80 percent Design Clarifier Tank(Solid Contact).xls Flocculation Mixing

17 Page of 5 Impeller Design Calculate impeller size and rotational speed. The rapid-mix basin will be an "up flow" type.experience shown that radial-flow mixers perform batter than axial-flow mixers in a vertical-flow basin Use Disc Turbine 6 Blade Blade width-to-diameter ratio 0.5 N P 6. (Table 8.5 Power Number ) P N n 3 d 5 n ρ P ρ P N Diameter of mixing tank (D).000 m Width of Rapid Mixing Tank Diameter of impeller (d) 0. to 0.D use 0.3 D Diameter of impeller (d) 1.00 m P 5 d rps rpm use gear box to convert rpm(standard motor) to rpm n 5 Check Reynolds number for turbulent flow N R 19,018 > 10,000 OK N R d nρ μ Therefore this equation is Valid 6 Dimentions of impeller are as follow - Diameter of impeller (d) 10.0 cm. - Width of impeller (W) 30.0 cm. 7 Check Impeller shaft torque P πnt Design Clarifier Tank(Solid Contact).xls Flocculation Mixing

18 Page 3 of N-m T choose motor gear rpm. Shaft torque N-m Use Standard motor of P' HP 8 Head loss through the mixer G gρ h tμ L.07853E-05 m. h L 9 Check Mixer Tip Speed Tip Speed πdn Tip Speed m/s (0.9 m/s m/s,kawamura) (Horizontal Shaft with Paddles) 10 Check Blade area/tank area 0.09 (Design Criteria ) m/s Design Clarifier Tank(Solid Contact).xls Flocculation Mixing

19 Page 5 of 5 (Horizontal Shaft with Paddles) Bladed Disk Turbine L W d Where : D Diameter of Mixing Tank (m) d Diameter of Bladed Disk Turbine (m) L Long of single bladed (m) W Width of single bladed (m) Equation : d 0. to 0. D L W d d 5 sourec : Water Treatment Process : Simple Option (S.Vigneswaran) Design Clarifier Tank(Solid Contact).xls Flocculation Mixing

20 Outlet Clarifier Tank Weir Loading m 3 /m.hr From Diameter Tank m. Minus outlet hole side 1 m. (Launders side) Length of weir m. 3 Q ( m / hr ) Length of weir 3 Weir Loading ( m / m. hr ) Weir Loading m 3 /m.hr OK. Give Diameter of Orifice 0.5 in m. Give 1 m. of outlet weir have orifice 5 pores/side side 50 pores Length of Orifice m./ 1 m. weir 1 side m./ 1 m. weir Then Free Space of weir m./ 1 m. weir Space between orifice to orifice m..73 cm. Give 1 m. of outlet weir have orifice 5 pores/side side 50 pores Then total orifice 35 pores Then sum area of orifice 0.06 m Flow Rate pass through 1 orifice 0.35 m 3 /hr Each of orifice area πd Each of orifice area m 0:9/7//007 1/3 Weir Loading/Design Clarifier Tank(Solid Contact)

21 Q Av Velocity pass through each orifice m/s 0:9/7//007 /3 Weir Loading/Design Clarifier Tank(Solid Contact)

22 Launders Launders Collection Water at Central Tank 0:9/7//007 3/3 Weir Loading/Design Clarifier Tank(Solid Contact)

23 3 Inlet Structure From Static Mixer Design criteria velocity pass through static mixer 1 - m/s Select velocity 1.5 m/s Q Av Q Area m v m Circular pipe area πd D D m in. 7 in. Calculation Surface Loading (Sedimentation Zone) Surface Area at Sedimentation Zone D outside D inside + ( xlaunders width ) π D D outside inside + xlaunderswidth π m. 6 m. Surface Area at Sedimentation Zone m Surface Loading Q A m/hr. Design Criteria m/hr upflow (radial upflow type) Text Book (Chularrongkron University <. m/hr.) Water Works Engineering m/hr Kawamura - 3 m/hr 1:07/7//007 1/1 Inlet structure&surface loading/design Clarifier Tank(Solid Contact)

1 Turbidity = NTU 2pH = 3 Alkalinity = mg/l as CaCO 3 4 Temperature = 5 Fe mg/l 6 Mn mg/l 7 Total Hardness mg/l as CaCO 3

1 Turbidity = NTU 2pH = 3 Alkalinity = mg/l as CaCO 3 4 Temperature = 5 Fe mg/l 6 Mn mg/l 7 Total Hardness mg/l as CaCO 3 DESIGN CALIFIER TANK (SLUDGE BLANKET CLARIFIER TYPE : VERTICAL SLUDGE BLANKET) 1. Flow Rate Q = 150 m /hr. Raw Water Quality input 1 Turbidity = NTU ph = Alkalinity = mg/l as CaCO Temperature = 5 Fe mg/l