عمليات الفصل التطبيقي

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  • W

    W

    K

    K

    ? ? ? ?K

    K

    K

  • KFUnit operationsE J

    K

    K

    K

  • K

  • - -

    W

    W

    W K K K K K

    K K K K K

    W

    K

    W K

    W K

    W

    K

  • - -

    WSettling & Sedimentation

    K W

    J

    K J K J

    K J

    K W

    FFree settlingE

    K W

    K

    1:2000.2%K

  • - -

    Motion of a Rigid Particle Through a Fluid

    K mv

    P

    cg g

    mgF =

    P

    gmF

    =

    FD

    AVCF DD 2

    2

    =

    CDW AWK Fg-Fb-FD

    Fg-Fb-FD =dtdVm

    dtdV

  • - -

    C

    D

    CPC gAVC

    ggm

    ggm

    dtdVm

    2

    2

    =

    15L1

    VtFTerminal Falling VelocityEFFree Settling VelocityKE

    W

    =0dtdv

    ( )

    DP

    Pt CA

    mgV = 2

    6

    3PPDm =

    DP

    ( )

    D

    Ppt C

    gDV

    34

    =

  • - -

    CDW

    CDK

    Pt DV=Re

    CD

    (wakes)

    CD

    FE~1000

    F1E

    100021051053

  • - -

    CDF2EK

    Rigid Spheres Re < 1

    Re24

    =DC

    ( )

    D

    Ppt C

    gDV

    34

    =

    ( )

    18

    2= PPt

    gDV

    1000 < Re < 21050.44 = CD

    CDK CD

    FEK

  • - -

    Behaviour of very fine particles

    K

    Non rigid sphere

    Finternal circulationE

    W

    Re = 50K Re = 100K Re = 10K

    Hindered settling

    W

    m

    pm

    =

    p

    ) 1( 8.1 2101

    =p

  • - -

    m

    ( )( )[ ]

    ( )

    =

    +=

    +=

    p

    ppmp

    pm

    1

    1

    pmmp

    ( )

    18

    22 pppt

    Dgv

    =

    p 2

    m

    mtpVD=Re

    ( )2

    23

    18 pmppgD =

    Re < 1K

  • - -

    Equipment for settling K Simple Gravity Settling Tank

    K

    Gravity Settling Chamber

    FResidence timeE

    K

    a i r o u t

    FE

  • - -

    FE

    FHE

    K

    Sedimentation FThickenerE

    K Thickener

  • - -

    K

    K

    FE

    W ( )

    c

    s

    VCUYQA 00 =

    Q0= Y = U = C0 =

  • - -

    VC =

    s = =

    W

    += X

    Awth S

    S

    R

    1

    tRK XK WK

  • - -

    FFEE

    20 m37.8 0C 101.3 RPa900kg /m3

    =1.137kg/m3 1.910-5 Pa.sK W

    ( )

    D

    PPt C

    gDV

    34

    =

    CD

    W

    ( )

    D

    PPt C

    gDV

    34

    =

    CDCDK

    5

    3

    5

    3

    100.2

    /900.1090.1

    /137.1

    =

    =

    =

    =

    P

    P

    D

    mkgsPa

    mkg

    PtDVN 1=

  • - -

    )1(137.11020

    109.15

    5

    LLL

    =

    NVt

    W

    ( )

    2

    5

    137.1310208.9137.19004

    tV

    =

    )2(207.0 2 LLLt

    D VC =

    Re=100

    FEVt=83.54 m/s FECD=2.96510-5

    1=CD CDReFCDEW

    =

    CD CD 100

    CD

    CD Vt Re

    CD

    99.9 12.46510-583.542 10085.120029.616 0.083 0.1251700 1316.26 0.0125 0.015

    1.283000 2961.6 8.35410-30.01Re0.01FE8.310-3 m/s = Vt

    ( )

    23

    4

    t

    PPD V

    gDC =

  • - -

    FFEE 6-4 m1.554

    2647 kg/m360 %K9980 kg/m3 1.00510-3 Pa.sK

    W

    ( )( ) ( )( )

    205.0) .6220 - 1 ( 82.110

    1) - 1 ( 82.110

    1/1553

    2467622.01998622.0

    12467

    6099840

    99840

    3

    ===

    =

    +=

    +=

    +=

    p

    pm

    mkg

    ( )

    ( ) ( ) ( )( )

    sm

    gDV mpPt

    /10525.110005.118

    205.0622.0 9982467 10554.1807.918

    3

    3

    224

    2

    =

    =

    =

    Re

    ( )( ) ( )

    ( )1121.0

    622.0 205.0/10005.11553 10525.1 10554.1

    /Re

    3

    34

  • - -

    FFEE 5kgkg

    1.5kgkgW

    Fkg water \ kg solidE2.5 3.1 3.7 4.2 5.0 (mm/s) 0.050 0.070 0.094 0.12 0.20

    1.33kg/s W

    ( )

    C

    S

    vCUYQA 00 =

    3

    00

    /10005.1

    /33.1

    mkgU

    skgCQ S

    =

    ==

    W Y vC ( /s) Y-U A m2 5 0.2 3.5 23.28

    4.2 0.120 2.7 29.93 3.7 0.094 2.2 31.12 3.1 0.070 1.6 30.4 2.5 0.050 1.0 26.6

    31.12 m2K

  • - -

    Jkg/m375000.5m/sK J101 k , 294 k200 m900 kg \ m3K

    0.457 m J5 kg water/kg solids

    1.5 kg water/kg solidsW

    (kg water/kg solids)2.5 3.1 3.7 4.2 5 2 1.2 0.94 0.70 0.50 (m/h)

    0.6 kg/s

  • - -

    W Filtration

    FFiltrateE

    K

    K

    FE

    FEK

    FE

    FVacuum E

  • - -

    K Filtration Theory

    W E K E K E K E K E K

    W

    ( )3

    1 21

    OC SVkLP

    =

    \ k1K

    K vK

    K LK

    SOK PCK

  • - -

    AdtdV

    V =

    dtdV

    =K A=K

    = VK

    ( )3

    221 1

    LSk

    PAdtdV

    O

    C

    =

    LvW

    ( ) VCAL SP = 1

    CSK

    P L

    ( )A

    VCSkP

    dtAdV

    P

    SO

    c

    2

    21 1

    =

    )1(LLL

    AVC

    PdtA

    dVS

    c

    =

  • - -

    ( )3

    21 1

    P

    OSk =

    )2(LLLm

    f

    RP

    dtAdV

    =

    Rm Pf

    FEFE

    )3(LLL

    +

    =

    mS R

    AVC

    pdtA

    dV

    Cf PPP +=K

    ( )

    3

    21 1

    P

    OSk =

    SO P

  • - -

    P

    ( )5PB =

    S1B S0.1-0.8

    )3(LLL

    +

    =

    mS R

    AVC

    pdtA

    dV

    ( ) ( ) BVKRPAPAVC

    dVdt

    PmS +=

    +

    =

    2

    ( )

    ( )PAR

    B

    PAC

    K

    m

    SP

    =

    =

    2

  • - -

    ( )

    VBVKt

    dvBVKdt

    P

    V V

    P

    +=

    += 2

    0 0

    2

    BVKVt P +=

    2

    VtV

    Vt

    V

    t VtK

    (Rm)K

    Constant Rate Filtration

    F3EW

    Slope = kp \ 2

    Intercept = B

  • - -

    =

    =

    +=

    =

    dtdV

    AR

    C

    dtdV

    AC

    K

    CVKdtdV

    AR

    VdtdV

    AC

    P

    m

    SV

    VmS

    2

    2

    KVC1 F-PEV

    K Continuous Filtration

    Rm

    VKdVdt

    P=

    2

    20 0

    VKt

    dVVKdt

    P

    t V

    P

    =

    =

    Filtration Practice W

    J

  • - -

    K J

    K J

    K

    J

    10-210K Filtration Equipment

    KK

  • - -

    FE

    K

    FE

    Plate and Frame Filter Press

    K

  • - -

    FEFE

    K

    f i l t r a t e

    FE

    K

  • - -

    FE

    Continuous Rotary vacuum Filter

    K

    FEK

  • - -

    FE

  • - -

    FE

    298.2k338KN/mKA = 0.0439m

    CS = 23.47kg/m3RmW V ( M3 ) t ( s )

    0.49810-34.4 1.0010-39.5

    1.50110-316.32.00010-324.6 2.49810-334.73.00210-346.13.50610-359.04.00410-373.64.50210-389.45.00910-3107.3

    W

    t/VVK

    =2PK

    6.00106 s/m6 = 2 =KP = B= 6400 s/m3

    ( )PAC

    K SP == 2

    61000.6

    =10-4 pa.s8.937 A = 0.0439 m2

  • - -

    ( ) ( )

    ( ) ( )110

    3

    4

    11

    3

    46

    1063.10103380439.0

    1093.86400

    /10863.1103380439.0

    47.2310937.81000.6

    =

    =

    ==

    =

    =

    mR

    RPA

    RB

    kgm

    m

    mm

  • - -

    FE FE20

    0.873m2FE3.37m3FKE

    W FE:

    106 s/m6KP= 6.00 B= 6400 s/m3

    Rm

    6

    26

    22

    211

    2

    22

    21

    1

    2

    2

    /93.3720873.0

    0439.01000.6

    1,1

    ms

    AAKK

    AA

    KK

    AB

    AK

    PP

    P

    P

    P

    =

    =

    =

    =

    ( )ms

    AABB

    /10.1620873.0

    0439.064002

    112

    =

    ==

    ( ) ( )( )

    s

    VBVK

    t P

    7.269

    37.310.1637.3293.372

    2

    22

    22

    22

    =

    +=

    +=

  • - -

    FE FE3.37 m3

    26.7 s%1020 m

    K

    ( )( ) sm

    BVKdtdv

    fPf

    /10737.110.1637.393.374

    1

    141

    33=+

    =

    +=

    s19410737.137.31.0

    3 =

    =HH

    min73.2760

    7.26960

    19420 =++

    =

  • - -

    FE 33%FE67 kpa0.171 kg solid/k

    2298 k

    0.893710-3Pa.s996.9 kg/m3K250s

    ( ) ( ) 3.091037.4 P= K

    W B = 0

    2

    2VKt P=

    t = = f tc = KP

    V2

    2

    = f

    ( )( ) ( )

    3

    3

    3

    113.039

    2

    /9.9961067

    .108937.0

    10225.110671037.4

    mkgPaP

    sPa

    PAC

    K SP

    =

    =

    =

    ==

    =

    filtratemCsolidkg S

    3

  • - -

    ssolidskgkg

    solidkg

    /1486.0s

    slurry kg 0.778 slurry

    191.0

    =

    = J

    0.778= kg \ s

    =2 = 2 0.1910.778

    = 0.2972 kg/s == 0.481 kg/s 0.778 - 0.2972 =

    filtratemsolidkg

    C

    sm

    S 34

    34

    30810825.4

    1486.09.996

    481.010825.4

    =

    =

    =

    = 250 = 0.1206 m3 4.82510-4

    ( )

    ( )( )

    2

    32

    2

    113

    2

    2