Wrd Ot Clarifier Calculations 445211 7

8/9/2019 Wrd Ot Clarifier Calculations 445211 7

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Clarifier Calculations

Prepared ByMichigan Department of Environmental Quality

Operator Training and Certification Unit


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Hydraulic Loading

Solids Loading


3/118

Clarifier Loading Calculations

=

Tank Volume, MG X 24

lo! into Tank, MG""etention Time #"T$

=lo!, gallons%day

Surface &rea, ft2Surface '(erflo! )ate #S')$

*eir '(erflo! )ate #*')$ = lo!, gallons%day

Lengt+ of *eir, ft

Solids Loading =Solids, ls%day

Surface &rea, ft2


4/118

-ut irst-ut irst


5/118

&rea

and

VolumeCalculations


6/118

Surface &rea Calculations

)ectangles

Surface &rea, ftSurface &rea, ft22= Lengt+, ft X *idt+, ft= Lengt+, ft X *idt+, ft

./am0le 13f a tank is 1 ft long and5 ft !ide,

!+at is t+e surfacearea6

S&, ft2= 1 ft X 5 ft = 5 ft2


7/118

./am0le 23f a tank is 1 ft 7 inc+es long

and5 ft 8 inc+es !ide,

!+at is t+e surface area in s9:

ft:6;'T

S&, ft2= 1:7 ft X 5:8 ft

)ectangles


Surface &rea CalculationsSurface &rea Calculations


8/118

7 inc+es = 7 inc+es12 in%ft

= :5 ft

Con(erting 3nc+es to eetCon(erting 3nc+es to eet

SoSo 1 ft 7 inc+es = 1:5 ft1 ft 7 inc+es = 1:5 ft

8 inc+es =8 inc+es

12 in%ft= :


9/118

./am0le 23f a tank is 1 ft 7 inc+es long

and5 ft 8 inc+es !ide,


ft:6

)ectangles



S&, ft2= 1:5 ft X 5:


10/118

)ectangles



*ork Calculations on Se0arate a0er

&ns!ers Gi(en on ;e/t Slides

ractice 1

3f a clarifier is 25 ft long and8 ft !ide,

!+at is t+e surface area in s9: ft:6

ractice 2

3f a clarifier is 22 ft > inc+es long

and< ft < inc+es !ide,



11/118

ractice 13f a clarifier is 25 ft long and8 ft !ide,


)ectangles



S&, ft2= 25 ft X 8 ft = 225 ft2


12/118

ractice 23f a clarifier is 22 ft > inc+es long



ft:6

)ectangles




13/118

> inc+es = > inc+es12 in%ft

= :25 ft

Con(erting 3nc+es to eetCon(erting 3nc+es to eet

SoSo

22 ft 7 inc+es = 22:25 ft22 ft 7 inc+es = 22:25 ft

< inc+es =< inc+es

12 in%ft= :5? ft

SoSo < ft < inc+es =


14/118

ractice 23f a clarifier is 22 ft > inc+es long



ft:6

)ectangles



S&, ft2= 22:25 ft X


15/118

Circles

"iameter

)adius = "iameter

2


"iameterT+e distance across a circle,

going t+roug+ t+e center:

)adius

T+e distance from t+e center a circle

to t+e 0erimeter:

)adius


16/118

Circumference =

distance around circle


Circles

"iameter

)adius

Circumference


17/118


0ie

Circles

"iameter

)adius


18/118


0i =

Circumference

"iameter=

= >:14>:14for any circle

Circles

"iameter

)adius


19/118


Surface &rea = r2

= >:14 X radius X radius

Circles

"iameter

)adius


20/118


Surface &rea = r2

& = >:14 X #"%2$2 = >:14 X "2

4

= :


21/118


./am0le 13f a tank +as a radius of 15 feet,


Surface &rea = r2

S & = r2 = >:14 X 15 ft: X 15 ft:

=


22/118


./am0le 23f a tank +as a diameter of 25 feet,


Surface &rea = r2

S & = r2 = >:14 X 12:5 ft: X 12:5 ft:

= 481 ft2

Circles

"iameter

)adius


23/118


Surface &rea = r2

Circles

"iameter

)adius

*ork Calculations on Se0arate a0er&ns!ers Gi(en on ;e/t Slides

ractice 1

3f a tank +as a diameter of 5:5 feet,


ractice 2

3f a tank +as a diameter of

5 feet < inc+es, !+at is t+e surfacearea6


24/118


ractice 13f a tank +as a diameter of 5:5 feet,


Surface &rea = r2

S & = r2 = >:14 X 25:25 ft: X 25:25 ft:

= 22 ft2

Circles

"iameter

)adius


25/118


ractice 2

3f a tank +as a diameter of5 feet < inc+es, !+at is t+e surfacearea6

Surface &rea = r2

< inc+es =< inc+es

12 in%ft= :5? ft

Circles

"iameter

)adius

5 feet ? inc+es = 5:5? ft

)adius = 5:5? ft A 2 = 25:28 ft


26/118


Surface &rea = r2

S & = r2

= >:14 X 25:28 ft: X 25:28 ft:

= 2? ft2

Circles

"iameter

)adiusractice 2

3f a tank +as a diameter of5 feet < inc+es, !+at is t+e surfacearea6


27/118

Volume Calculations

Volume B T+ree "


28/118

Volume Calculations

Volume B T+ree "imensions

Lengt+*id

t+"e0t+


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)ectangular Tanks

Volume = Lengt+ X *idt+ X Heig+t #or "e0t+$

./am0le 1

3f a tank is 1 feet long, 5 feet !ide, and 5 feet

dee0, !+at is t+e (olume in cuic feet6

Vol: = 1 ft X 5 ft X 5 ft = 25 ft>

Volume Calculations


30/118

)ectangular Tanks


./am0le 2

3f a tank is 2 ft: long, < ft: !ide, and 5:5 ft:


Vol: = 2 ft X < ft X 5:5 ft =


31/118

)ectangular Tanks


./am0le >

3f a tank is 25 ft: long, 8 ft: > inc+es !ide, and


32/118

)ectangular Tanks


T+ere are


33/118

)ectangular Tanks


Volume Calculations

14ft> X = 12,8

3f a tank is 25 ft: long, 8 ft: > inc+es !ide, and


34/118

)ectangular Tanks

Volume Calculations

ractice 1

3f a tank is 21 feet long, 8 feet !ide, and < feet dee0, !+at is t+e (olume in cuic feet6

ractice 2

3f a tank is 22 ft: long, 8 ft: !ide, and

3f a tank is >5 ft: long, 12 ft: > inc+es !ide, and 8:5 ft: dee0, !+at is t+e (olume in

gallons6




35/118

)ectangular Tanks


ractice 1

3f a tank is 21 feet long, 8 feet !ide, and < feet


Vol: = 21 ft X 8 ft X < ft = 1>2> ft>

Volume Calculations


36/118


37/118

)ectangular Tanks


Vol: = >5 ft X 12:25 ft X 8:5 ft = 4 ft>

Volume Calculations

ractice >

3f a tank is >5 ft: long, 12 ft: > inc+es !ide, and

8:5 ft: dee0, !+at is t+e (olume in gallons6


38/118


39/118

)ectangular Tanks


Volume Calculations

4ft> X = >,477 gallons

ractice >

3f a tank is >5 ft: long, 12 ft: > inc+es !ide, and

8:5 ft: dee0, !+at is t+e (olume in gallons6

Vol: = >5 ft X 12:25 ft X 8:5 ft = 4 ft>


40/118

Volume Calculations

)ound #Cylinder$ Tanks

= >:14

r = )adius of circle

+ = Heig+t #or "e0t+$


V = r2

+

C


41/118

Volume Calculations


./am0le 1

ind t+e Volume in cuic feet of a tank

+a(ing a radius of 1 feet and a de0t+

of ? feet:

V= r2+

= >:14 X ? ft>

= 2512 ft>

= >:14 X 1 ft X 1 ft X ? ft


42/118

V l C l l ti


43/118

Volume Calculations


./am0le >

ind t+e Volume in gallonsof a tank

+a(ing a diameter of 5 feet and a de0t+ of 8feet:

V= r2+ = >:14 X 25 ft X 25 ft X 8 ft

= 1

= 1>2,117 gallons

X

V l C l l ti


44/118

Volume Calculations


= >:14

r = )adius of circle

+ = Heig+t #or "e0t+$


V l C l l ti


45/118

Volume Calculations


ractice 1

ind t+e Volume in cuic feet of a tank +a(ing a radius of 22 feet and a de0t+ of 1 feet:

ractice 2 ind t+e Volume in cuic feet of a tank +a(ing a diameter of 2? feet

and a de0t+ of

ind t+e Volume in gallonsof a tank +a(ing a diameter of 4? feet

and a de0t+ of < feet:



V l C l l ti


46/118

Volume Calculations


ractice 1

ind t+e Volume in cuic feet of a tank

+a(ing a radius of 22 feet and a de0t+of 1 feet:

V= r2+

= >:14 X 4?4 ft>

= 15,18? ft>

= >:14 X 22 ft X 22 ft X 1 ft

V l C l l ti


47/118

Volume Calculations


ractice 2

ind t+e Volume in cuic feet of a tank+a(ing a diameter of 2? feet and a de0t+

of :14 X 14 ft X 14 ft X :14 X 14

= 4717 ft>


48/118


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Vol me Calc lations


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Cylinder !it+ Cone -ottom

cylinder = r!h"

cone = "#$ r!h or r

!h!$

h1

h2

Vtotal = Vcylinder Vcone

Volume Calculations

Volume Calculations


51/118

Cylinder !it+ Cone -ottom

Volume Calculations

Side *ater

"e0t+

or Secondary Clarifiers

Volume of Cone ;ot Considered

3nsignificant Com0ared to Total Volume

#illed !it+ Sludge$

Clarifier LoadingClarifier Loadin

g


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Clarifier LoadingClarifier Loading

"etention Time #"T$

T+e time it takes for a dro0 of !ater to

tra(el from inlet to outlet

Hydraulic Loading


53/118

Clarifier "etention Time

Must Ha(e "etention Time Long .noug+ for Solids to Settle

Sedimentation .fficiency


54/118

Time, Hrs:

Sedimentation .fficiency

=e

rcent)

emo(

al

" ! $ %&

!&

'&

"&&

%&

(&

Too Long B ;o 3ncrease in )emo(al


g


55/118


"etention Time #"T$



Hydraulic Loading

Ty0ical "esign Value = 2 B > Hours

) d li * di

)ydraulic *oading


56/118

"etention Time =Volumelo!

=25, gallons

>1, gallons%day = :? "ays

)ydraulic *oading)ydraulic *oading

"etention Time = Tank Volume3nfluent )ateE+ample "a,

Calculate the Detention Timein for a clarifier -ith a

volume of !./&&& gallon0that receive0 a flo- of $"&/&&& gal#day1

) d li * di

)ydraulic *oading


57/118

)ydraulic *oading)ydraulic *oading

"etention Time = Tank Volume3nfluent )ateE+ample "2,

Calculate the Detention Timein )OU34for a clarifier -ith

a volume of !./&&& gallon0that receive0 a flo- of $"&/&&& gal#day1

"etention Time =Volumelo!

=25, gallons

>1, gallons%day = :? "ays

:? "ays X 24 +ours%days = 1:8 Hours


g


58/118


"etention Time #"T$



Hydraulic Loading

"etention Time"etention Time ==Tank VolumeTank Volume

lo! into Tanklo! into Tank


g


59/118


"etention Time #"T$



Hydraulic Loading

"T, +rs"T, +rs == Tank Volume, #MG or Gallons$ X 24Tank Volume, #MG or Gallons$ X 24

lo! into Tank, #MG%" or Gal%"$lo! into Tank, #MG%" or Gal%"$

"etention Time"etention Time


60/118


./am0le 1: ind t+e detention time in +ours of a

circular sedimentation tank +a(ing a (olume of


61/118



circular sedimentation tank +a(ing a (olume of55, gallons and a flo! of :


62/118



circular sedimentation tank +a(ing a (olume of55, gallons and a flo! of :


63/118



64/118


ractice 1: ind t+e detention time in +ours of a

clarifier +a(ing a (olume of 52, gallons and a flo!of 52, gallons 0er day:

"T, +rs =Tank Volume, gallons

lo! into Tank, gallons%day X 24 +r%day

"T, +rs =52, gallons

52, gallons%day

X 24 +r%day

= 2:4 +our



65/118


ractice 2: ind t+e detention time in +ours of a

rectangular sedimentation tank +a(ing a (olume of17,4 gallons and a flo! of :225 MG":

"T, +rs =Tank Volume, gallons

lo! into Tank, gallons%day X 24 +r%day

:225 MG" = 22, gal%day


66/118


g


67/118


"etention Time #"T$



Hydraulic Loading

"T, +rs"T, +rs == Tank Volume, #MG or Gallons$ X 24Tank Volume, #MG or Gallons$ X 24lo! into Tank, #MG%" or Gal%"$lo! into Tank, #MG%" or Gal%"$


"etention Time"etention Time ==Tank VolumeTank Volume

lo! into Tanklo! into Tank


g


68/118


Hydraulic Loading

Surface '(erflo! )ate #S')$')

Surface Loading )ate #SL)$

T+e flo! in gallons 0er day into t+eclarifier 0er s9uare foot of surface area


g


69/118


Hydraulic Loading

Surface '(erflo! )ate #S')$')

Surface Loading )ate #SL)$

T+e flo! in gallons 0er day into t+eclarifier 0er s9uare foot of surface area

S'), g0d%ft2

=

lo!, gallons%day

Surface &rea, ft2


70/118


g


71/118


Hydraulic Loading

Surface '(erflo! )ate #S')$

S'), g0d%ft2 =lo!, gallons%day

Surface &rea, ft2

Ty0ical "esign Value = 4 D ? gal%day%ft2


g


72/118


Hydraulic Loading D Surface '(erflo! )ate #S')$


Surface &rea, ft2

./am0le 1:Calculate t+e Surface '(erflo! )ate for a clarifier t+at is 5 ft long,

15 ft !ide, 12 ft dee0, and recei(es a flo! of >>?, gallons 0er

day:

= 5 ft X 15 ft = >?, gallons 0er day


73/118




Surface &rea, ft2

./am0le 2:Calculate t+e Surface '(erflo! )ate for a clarifier t+at +as a

diameter of 7 ft, and recei(es an influent flo! of 1:75 MG":

= 1,75, gallons 0er day

lo!, gallons%day = 1:75 MG" X 1,,

Surface &rea, ft2= r2

= 2?27 ft2

= >:14 X > ft X > ft


g


74/118

Clarifier LoadingC a e oad g



Surface &rea, ft2

./am0le 2:Calculate t+e Surface '(erflo! )ate for a clarifier t+at +as a

diameter of 7 ft, and recei(es an influent flo! of 1:75 MG":

1,75, gallons 0er day

2?27 ft2S'), g0d%ft2 =

= 5?4 g0d%


75/118


g


76/118

Clarifier Loadingg



Surface &rea, ft2

ractice 1:Calculate t+e Surface '(erflo! )ate for a clarifier t+at is >5 ft long,

8 ft !ide, < ft dee0, and recei(es a flo! of 2>5, gallons 0er day:

= >5 ft X 8 ft = >15 ft2Surface &rea, ft2

2>5, gallons 0er day >15 ft2S'), g0d%ft2 =

=


77/118

C a e oad gg



Surface &rea, ft2

ractice 2:Calculate t+e Surface '(erflo! )ate for a clarifier t+at +as a

diameter of 45 ft:and recei(es an influent flo! of :75 MG":

= 75, gallons 0er day

lo!, gallons%day = :75 MG" X 1,,

Surface &rea, ft2= r2

= 158 ft2

= >:14 X 22:5 ft X 22:5 ft


g


78/118

gg



Surface &rea, ft2

ractice 2:Calculate t+e Surface '(erflo! )ate for a clarifier t+at +as a

diameter of 45 ft, and recei(es an influent flo! of :75 MG":

75, gallons 0er day

158 ft2S'), g0d%ft2 =

= 48 g0d%ft2


g


79/118

gg

Hydraulic Loading



Surface &rea, ft2

Ty0ical "esign Value = > D 12 gal%day%ft2

#? gal%day%ft2

$


g


80/118

gg

Hydraulic Loading

*eir '(erflo! )ate #*')$

T+e flo! in gallons 0er day 0er

linear foot of !eir

*'), gal%d%ft =lo!, gallons%dayLengt+ of *eir, ft

Ty0ical "esign Value = E1, gal%day%ft


g


81/118

gg

Hydraulic Loading D *eir '(erflo! )ate #*')$

*'), gal%d%ft = lo!, gallons%dayLengt+ of *eir, ft

)ectangular Tanks D Lengt+ of *eir, ft


82/118


g


83/118

gg


*'), gal%d%ft =lo!, gallons%day

Lengt+ of *eir, ft

Lengt+ of *eir, ft

./am0le 1

& 0rimary clarifier is 2 feet !ide, 7 feet long, and +as a S*" of 12 feet:

T+e clarifier +as t!o effluent troug+s across t+e !idt+ t+at allo! t+e !ater

to flo! o(er ot+ sides of eac+ troug+: T+e a(erage flo! to t+e clarifier is

:75 MG": Calculate t+e !eir o(er flo! rate for t+is clarifier:

L'*

lo!, gallons%day = : 75 MG" X 1,, = 75, gal%day

= 4 X *idt+

= 4 X 2 ft

= ? ft


g


84/118

gg



Lengt+ of *eir, ft

./am0le 1

& 0rimary clarifier is 12 feet !ide, 4 feet long, and +as a S*" of ? feet:




L'*

= ?,125 gal%day%ft

=75, gal%day

? ft


85/118


g


86/118

gg



ractice 1

& 0rimary clarifier is 1? feet !ide, 45 feet long, and +as a S*" of 8 feet:

T+e clarifier +as an effluent troug+ across t+e end: T+e a(erage flo! to

t+e clarifier is :?5 MG": Calculate t+e !eir o(er flo! rate for t+is

clarifier:

L'*

= 8,444 gal%day%ft

?5, gal%day8 ft

lo!, gallons%day = : ?5MG" X 1,, = ?5, gal%day

Lengt+ of *eir, ft = *idt+

*'), gal%d%ft =


g


87/118

gg



Lengt+ of *eir, ft

Lengt+ of *eir, ft

ractice 2

& 0rimary clarifier is 12 foot !ide, 4 foot long, and +as a S*" of ? feet:




L'*

lo!, gallons%day = : 41 MG" X 1,, = 41, gal%day

= 4 X *idt+

= 4 X 12 ft

= 4? ft


88/118


g


89/118


g


*eir Lengt+ for a Circular Clarifier6



90/118

Circumference =


Circles

"iameter

)adius

Circumference



91/118

Circumference =


Circles

"iameter

)adius

Circumference

= >:14 for any circle==Circumference

"iameter

C

"

C = "


92/118


g


93/118



*eir Lengt+ for a Circular Clarifier


g


94/118



./am0le 1:T+e flo! to a circular clarifier is 78,gallons 0er day: T+e

clarifier is 24 feet in diameter !it+ t+e !eirs set 1 foot from t+e

outside !all, for a !eir diameter of 22 feet: Calculate t+e !eir

o(erflo! rate:22 feet

Lengt+ of *eir, ft = X *eir "iameter

= >:14 X 22 ft

= 78:? ft


g


95/118



./am0le 1:T+e flo! to a circular clarifier is 78,gallons 0er day: T+e

clarifier is 24 feet in diameter !it+ t+e !eirs set 1 foot from t+e

outside !all, for a !eir diameter of 22 feet: Calculate t+e !eir

o(erflo! rate:22 feet

*'), g0d%ft =

78, g0d

78:? ft

= 8,8?? g0d%ft



96/118


./am0le 2:

T+e flo! to a circular clarifier is 1:75 MG": T+e clarifier is 7

feet in diameter !it+ t+e !eir set in 1 foot from t+e outside !all:

Calculate t+e !eir o(erflo! rate: 5? feet


= >:14 X 5? ft

= 1?2 ft

*'), g0d%ft =1,75, g0d

1?2 ft= 8,77 g0d%ft



97/118

ractice 1:

T+e flo! to a circular clarifier is :? MG": T+e clarifier is >


Calculate t+e !eir o(erflo! rate:

ractice 2:

T+e flo! to a circular clarifier is 1:4 MG": T+e clarifier is 54 feet

in diameter !it+ t+e !eir set in 1 foot from t+e outside !all:

Calculate t+e !eir o(erflo! rate:

ractice >:

T+e flo! to a circular clarifier is 2:1 MG": T+e clarifier is


98/118


ractice 1:

T+e flo! to a circular clarifier is :? MG": T+e clarifier is >


Calculate t+e !eir o(erflo! rate: 2? feet


= >:14 X 2? ft

= ?? ft

*'), g0d%ft =?, g0d

?? ft= 8,81 g0d%ft



99/118


ractice 2:

T+e flo! to a circular clarifier is 1:4 MG": T+e clarifier is 54 feet

in diameter !it+ t+e !eir set in 1 foot from t+e outside !all:

Calculate t+e !eir o(erflo! rate: 52 feet


= >:14 X 52 ft

= 17> ft

*'), g0d%ft =1,4, g0d

17> ft= ?,5?8 g0d%ft



100/118


ractice >:

T+e flo! to a circular clarifier is 2:1 MG": T+e clarifier is


101/118

Hydraulic Loading


T+e flo! in gallons 0er day 0er linear foot

of !eir


Ty0ical "esign Value = E1, gal%day%ft

Clarifier Loading


102/118

Solids Loading

SL), ls%d%ft

2

=

Solids, ls%day

Surface &rea, ft2

T+e 0ounds 0er day of solids in t+e clarifier influent

0er s9uare foot of surface area

Same Calculations as for

Hydraulic Loading

S& = L X * S& = r2

D Solids Loading )ate #SL)$

Clarifier Loading


103/118

Solids Loading

SL), ls%d%ft2 =Solids, ls%day

Surface &rea, ft2

T+e 0ounds 0er day of solids in t+e clarifier influent

0er s9uare foot of surface area

Founds .9uation


Founds .9uation


104/118

ounds =

Concentration

'f ST@

3n t+e

*ater

Conc: / lo! #or Volume$ / ?:>4 Ls%gallon

X

uantity

'f *ater

T+e ST@

3s 3n

*eig+t

'f T+e

*aterX

Founds .9uation


105/118

lo! #(olume$ and concentration must e

e/0ressed in s0ecific units:

lo! or (olume must e e/0ressed

as millions of gallons

gallons I

1,, gal%MG= MG

i:e:$ & tank contains 1,125, gallons of !ater: Ho! manymillion gallons are t+ere6

1,125, gal = 1:125 MG

1,, gal%MG

Founds .9uation


106/118

Concentration must e e/0ressed

as 0arts 0er million 0arts:Concentrationusually re0orted as

milligrams 0er liter:

T+is unit is e9ui(alent to 00m:

1 mg = 1 mg = 1 mg = 00m

liter 1 grams 1,, mg

00m = arts

Mil arts= Ls:

Mil Ls:

Founds .9uation


107/118

Ls: =

*+en flo!#(olume$ is e/0ressed as

MGand conc:is in 00m, t+e units cancel to lea(e only pounds:

Concentration/ lo! #or (olume$ /?:>4 ls%gallon

Ls:M Ls:

X XM gal Ls:gal

Founds .9uation


108/118

3f t+e flo!rate is entered inM gal 0er day #MG%"$,t+e

ans!er !ill e inls%day:

./am0le

T+e flo! to a clarifier is 1:2 MG" and t+e concentration

of sus0ended solids in t+e flo! is 25 mg%L: Ho! many

0oundsof sus0ended solids come into t+e clarifier eac+ day6

Ls%day = conc: #mg%L$ / flo! #MG"$ / ?:>4 ls

gal

Ls%day = 25 mg%L / 1,2, gal%day / ?:>4 ls

1,, gal%MG gal

= 25 / 1:2 / ?:>4

= 25,2 Ls%day

Clarifier Loading


109/118

Solids Loading

SL), ls%d%ft2 =Solids, ls%day

Surface &rea, ft2

T+e 0ounds 0er day of solids in t+e clarifier influent0er s9uare foot of surface area


Ty0ical "esign Value = Ma/ > ls%d%ft2

Clarifier Loading


110/118

Solids Loading

SL), ls%d%ft2

=

Solids, ls%day

Surface &rea, ft2


./am0le 1:Calculate t+e Solids Loading )ate for a clarifier !it+ a 5 ft diameter

and a de0t+ of 12 feet, and recei(es a flo! of 2:4 MG" !it+ a

sus0ended solids concentration of 1? mg%L:

S& = >:14 X 25 ft X 25 ft = 1872:5 ft2

1? mg%L X 2:4 MG" X ?:>4 ls%gal = >7,28 ls%d

>7,28 ls%day

1872:5 ft2= 1?:4 ls%d%ft2

Solids, ls%day =

SL), ls%d%ft2 =

Clarifier Loading


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Solids Loading

SL), ls%d%ft2

=

Solids, ls%day

Surface &rea, ft2


./am0le 2:Calculate t+e Solids Loading )ate for a clarifier !it+ a >1 ft diameter

and a de0t+ of 8 feet, and recei(es a flo! of :14 X 15:5 ft X 15:5 ft =


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Solids Loading D Solids Loading )ate #SL)$



ractice 1:

Calculate t+e Solids Loading )ate for a clarifier !it+ a 12 ft !idt+ and a lengt+ of 5feet, and recei(es a flo! of 7, gallons 0er day !it+ a sus0ended solids

concentration of >4 mg%L:

ractice 2:

Calculate t+e Solids Loading )ate for a clarifier !it+ a 22 ft radius and a de0t+ of ?:5

feet, and recei(es a flo! of 1,45, gallons 0er day !it+ a sus0ended solidsconcentration of >4 mg%L:

ractice >:

Calculate t+e Solids Loading )ate for a clarifier !it+ a 22 ft diameter and a de0t+ of 4 ls%gal = 41,117 ls%d

41,117 ls%day

152 ft2= 2


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Solids Loading

SL), ls%d%ft2

=

Solids, ls%day

Surface &rea, ft2


ractice >:Calculate t+e Solids Loading )ate for a clarifier !it+ a 22 ft diameter

and a de0t+ of < feet, and recei(es a flo! of :?2 MG" !it+ a

sus0ended solids concentration of 185 mg%L:

S& = >:14 X 11 ft X 11 ft = >? ft2

185 mg%L X :?2 MG" X ?:>4 ls%gal = 1>,>>7 ls%d

1>,>>7 ls%day

>? ft2= >5:1 ls%d%ft2SL), ls%d%ft2 =


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Clarifier Loading Calculations

Tank Volume MG X 24"etention Time #"T$


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DT, hrs =Tank Volume, MG X 24

Flow into Tank, MGD


SOR, !"#$t2 =Flow, allons#"a%Sur$a&e 'rea, $t2


Ty0ical "esign Value = 4 D ? gal%d%ft2


(OR, al#"#$t =Flow, allons#"a%)enth o$ (eir, $t

Ty0ical "esign Value = E1, gal%d%ftSolids Loading

S)R, l*s#"#$t2 =Soli"s, l*s#"a%

Sur$a&e 'rea, $t2

Ty0ical "esign Value = 25 D > ls%d%ft

2

Cl ifi C l l ti


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Prepared By

Michigan Department of Environmental Quality

Operator Training and Certification Unit

Documents

Wrd Ot Clarifier Calculations 445211 7