()
1 2 3 4 5 6
1 1-1,... 1-2 (suspended solids),, (dissolved solids), (source) <1-1>
<1-1> : (disolved solids) (suspended solid) [10-4 < d < 1] (source) [10-3 <d<1] [ d > 1],,, SiO2, Fe2O3 Al 2 O 3, MnO 2 CO 2 Ca 2+, HCO - 3, Cl -, Mg 2+,Na +, SO 2-4, K +,Fe 2+, NO - 3, Mn 2+, Zn 2+ CO 2-3, F -, OH - N 2, O 2, CO 2, SO 2 H+ HCO 2-3 -, SO 4 ( ), CO 2, O 2,, N 2, H 2 S,, Na +, NH + 4, Cl -, HCO - 3, CH 4, H + NO - 2, NO - 3, OH -, HS -,,,, DDT, PCB, BHC * 0.45,. 1, ( ) ( ) 10 ~.
1-3,.,., 2 ( ) 2. < 1-1>, < 1-2~3>,,. < 1-1> : () < 1-2> : ()
< 1-3> : () 1-4 (1) ( ), - - - :,,, ( 1-4~5 ) - IN-LINE FILTRATION - DIRECT FILTRATION - CINVENTIONAL TREATMENT - ADVANCED TREATMENT < 1-4> : ()
< 1-5> : ()
< 1-6> : ()
2 2-1 / 1 1. (1 ), (1 ), ( ), (1~10), (1~ ).,,. 2-2. " mixing", (rapid mixing) flash mixing, mixing
(rapid mixing) - alum 20 ppm alum 1: 50,000. alum floc (rapid mixing). -, - alum 6 monomer, medium polymer Al(OH) 3 3+ Al(H 2 O) 6 Al(OH)(H 2 O) 5 Al 13 O 4 (OH) 24 Al(OH) 3 (precipitate) 2-3 (1),. (Instantaneous Flash Mixier) IN LINE (In Line Static Mixer) IN LINE (In Line Blender Mixer) (Hydraulic Mixing) (Mechnical Mixing) (2), no headloss nozzle <5 NTU very effective >0.7kg/cm 2 < 2,500 mm -alum < 1 % - (FeCl 3 )< 5 % In-Line Static no moving parts quite effective : 1~3 sec. : : 0.6 m : screen Hydraulic : - Parshall Flume - Venturi Meter - Weir Mechanical Backmixing
FlashMixer In-LineBlender InstantaneousFlash Mixer 1,2 1 In-LineBlender Orifice2 300750/sec -1 1: 750 1,000/sec -1 2 :300500/sec -1 5001,000/sec -1 3060sec 1 :3sec 2 :2040sec 12sec 1 2..... 2.. 2. Ø2200m/m.. Ø600m/m... 1 Orifice.... (50,000TON/ 22KW 5.5KW 3.7KW ) ( 100% 130% 70% )
(a) hydraulic mixing < 2-1> : ()
(b) in-line static mixing (c) (Instantaneous Flash Mixer)
3 3-1 floc (gentle mixing) floc. mechanism floc. 3-2
3-3 (1) (Mechanical Mixing) - vertical shaft type (turbine propella blade) floc --> - paddle type ( shaft) floc --> Baffled Channel Basins :, ( :0.3 ~ 0.6 m) Contact Flocculation Diffused Air, Water Jet Agitation vertical shaft flocculator (flexibility) (effectiveness) 1 < 3-1~2 : ()>
3-4
4 4-1 (sedimentation) (floatation) / floc. ( )., /.. 4-2
4-3
4-4 (1) (Overall Treatment Process) : () : - - < 2 NTU () - - 5~7 NTU -, 2 (2) (settling velocity) (Settling Velocity, v s ) v s = [g * ( s - w ) * d 2 s ] / 18 * (v s :, g :, s, w :, d s :, : ) : floc, (v o, Surface Loading Rate, Overflow Rate) v o = Q / (B * L) (Q :, B * L = ) : (critical settling velocity) - > ( ) : - < ( ): (E) = v s / v o ( / ) = v s * (B*L) / Q :, (B*L)--> ( ) (v s ) --> (, ) (Q) --> : Jar Test ( 1.5 ) <4-1> : ( : 10 C)
Mesh mm (mm/sec.) (m/hr.) 2.65 18 1.0 100 360 2.65 70 0.2 21 76 2.65 200 0.03 6 22 2.65-0.02 0.62 2.3 alum floc 1.001-1 ~ 4 0.2 ~ 0.9 0.71 ~ 3.3 floc 1.002-1 ~ 3 0.4 ~ 1.2 1.5 ~ 4.3 (3) (Flow Short Circuiting) (Improper Design) - - - - Re-No. Fr-No. (Re = v * R /, Fr = v 2 / (g * R)) - - (Density Flow) - - ( > 50 NTU) - (, 1963) v = [(2*g* *h* ) / ( *k)] 0.5 (v : (m/s), : (g/cm 3 ), : (1.0 g/cm 3 ), g : (9.81 m/s 2 ), h : (m), : (0.5), k : (1.5~2.0)) --> 0.2 ~ 0.5C 0.8 ~ 1.8 m/min. ( : 0.4 m/min.)
(4) - - compact - (metal) - : 50~100 % - (Fr. No. ) - - - (5) ( ) - : ( ) - < 1 cm ( floc ) - : 0.075 ~ 0.2 m ( ) - : 0.25 ~ 0.5 m ( ) - : -. --> 2~2.5 m (floc ) trough : transverse, finger (rectangular basin) filger -type - - - weir : v - notch, orifice orifice - scum - floc - (weir v-notch ) - orifice < 0.5 ~ 0.75 m/s (floc ) (6) (Shape of the Tank)
: : - Re = v * R / < 2,000 - Fr = v 2 / (g * R) > 10-5 (Re : Reynolds,v : (m/s), R(A/P) :, : (m 2 /s), g : (9.81 m/s 2 )) --> (R) --> Re - No., Fr.-No. --> 4-3 ( ) ( ) - : - :. 0.83~2.5 m/h 0.9 ~ 2.7 m/h. - : 3~5 m - : 3~5.5 m. - : - :3~5hr. ( ). 1.5 ~ 3hr. - / :1/3~8 a. - / >1/5 - < b. - weir < 0.4 m/min 11 m 3 /m.h - weir < 14.5~16.7m 3 /m.h. - :,. - :. 1.3~1.9m/h (. - : 3 ~ 5m ) a. - :1~3h b. - weir < 7 m 3 /m.h - :20. - :1~2h compact - :..2 ~ 3 m/h a. - weir < 7.3~15 m b. 3 /m.h - < 50 mm/min. - :20 - :1~2h - :. 2 ~ 3 m/h. compact - weir < - :1.5~2h ( a. 7.3 ~ 15m 3 /m.h - : ) - < 40~50 mm/min. b. 10 mm/min. - : 3~5 - -
5 5-1,..., mechanism. 5-2 (Mechanism)
5-3 (1) ( ) : 2 ( ) (2) : 4~5 m/( ), 0.3~0.45 mm 70~90cm :, 120 m/,, ( ) (3) (Conventional Filtration) : (Direct Filtration) In-Line Filtration (4) ( + ) ( + ) GAC (Granular Activated Carbon) (BAC ) Precoat
(5) : :, 5-4 (1) :, --> (, KMnO 4 ) + In-Line Filtration + --> ( ) : --> : ( ) 2 : --> (2) ( -> ) GAC : EBCT (15~30 ) --> 1.8 ~ 2.4 m ( 5 ~ 10 m/h)
(3) (<150 m 2 ): : 4(, ), 2( ), 6( ), ( ) :. --> 15 ~ 20 % (N) = 1.2 Q 0.5 (Q : (MGD, 1 MGD=3,785 m 3 /) (4) (v f ) = (m 3 /) / (m 2 ) : 25 m/h. ( ) < 180 m/, ( ) < 360 m/ -->,,, --> 1.8 m (5) - polymer ( ) :, - : - (, ) : ph - (PAC) :. - (,, ) - - - :, polymer, PAC - :,,, - :, polymer
(6), (orifice type), :,, : 6, : - - - - (7) (, ) :,. - - - - (L / D - Ratio) -->, - - pilot plant test - (L / D - Ratio), ( + ) : L/D > 1,150 (3), (coarse monosand) : L/D > 1,400 - (2 ) d 1 / d 2 = [( 2 - w ) / ( 1 - w )] 0.667 (d 1, d 2 :, 1, 2, w : )
(8) - ( ) - ( ) - ( ) - - - - - + - + (air and water) - (air scouring) (9) trough - Fluidized Bed ( ) trough ( ) : 1.8 ~ 2.4 m, 0.8 ~ 1.2 m( ) trough (H O ) : 0.5 L + D < H O < L + D trough (S) : 1.5 H O < S < 2.5 H O (, L :, D : trough, Ho : trough ) - Air Scour (partial fluidized) weir (B = 0.5 m) trough : floc trough 0.9 m trough : U - type, V - type ( flat) (10) - - - - scale - - - strainer - type, polyethylene block --> air scour - block, - wheeler - < 5-1> : ()
< 5-2> :
( ) ; sand anthracite, sand (d s ) 0.55 mm, 1.5, ( s ) 2.65, 1.5, ( a ) 1.6anthracite (d a )? --> d s 0.55 mm (d 60 /d 10 ) d 60 = 0.825 mm 2.65, anthracite d 60 (anthracite) = 1.53 mm anthracite d 60 anthracite (d a ) = 1.02 mm. say 1.0 mm
< 5-3> : ( )
6 6-1.,.,,,,,. 6-2 (1) 1903, (2) THM (3) - - - - (4),,, 1 mg/l - (NH 3 ) : 7.6 ~ 15 mg/l - (H 2 S) : 8.5 mg/l - 2(Fe 2+ ) : 0.6 mg/l - 2 (Mn 2+ ) : 1.3 mg/l - (NO - 2 ) : 1.5 mg/l (5) (HOCl >>> OCl) (6) Cl 2 + H 2 O --> HOCl + H + + Cl - HOCl --> OCl - + H +
-, ph,,, (7) ph : 6 ~ 7, : 20 ~ 25C, > 30 min. > 0.5 mg/l ( : >0.2 mg/l, >1.5mg/l (8) THM THM - + --> THM + - ph - CHCl 3 ( )4 - THM :., GAC, PAC - :,, - THM 6-3 CT.,. SDWA Amendments (1989) Giardia Cyst99.9% (3 log), Entric Viruses99.99% (4 log),,,, MCL., 99.9%Giardia Cyst Entric Viruses 99.99%. Virus Giardia CystVirus. ph7 0.5 2 mg/ Giadia99.9% CT( )236, 99.99% CT 12. Giardia CystCryptosporidium. 99.9%Giardia Cyst99.99%Entric Viruses. SWTR(US EPA, 1989), (C) (/ ) (T) ()
CT. Tracer 10% (T 10 ). 6-1Giardia Cyst1 log CT(US EPA, 1989). EPA CT, CT, CT., Giadia CystCryptosporidium,. ph 6-1 Giardia Cyst 90% Inactivation CT 1 5 10 15 20 25 6 55 39 29 19 15 10 7 79 55 41 28 21 14 (2 / ) 8 115 81 61 41 30 20 9 167 118 88 59 44 29 69 0.97 0.63 0.48 0.32 0.24 0.16 69 21 8.7 7.7 6.3 5 3.7 69 1270 735 615 500 370 250 10 4 10 6 /m (Brazos and O'Connor 1993). (Regrowth).,,,,,,.,. CT,, ph. C, T 10. T 10 (basin) 90%
T 10 C. T 10 (Tracer) baffling degree 6-2 (T 10 = T( )baffling factor). 6-2 (EPA Guidance Manual, 1991) 0.1,, 0.3, 0.5 0.7* 1.0,, *;.,.
.,. 1.,, 2. Kawamura, Integrated Water Treatment Plant Design, AWWA, 1998 3.,, 1997 4.,, 5. Water Treatment Plant Design, AWWA, 1997 6.,, 2001 7.,,, 2002