1553.pdf

A B S T

R A

C T

S

ha r o n

N

a_{p p}

ie r :

T

h

e U s e of T he r

m

al In a ctiv ation of

M

ale-

S

pe ci fi c Col i p ha_ge s a s Pote nt

ia

l

In

d

ic ato r s o f Patho _ge n Re

d

u ct

i

o n s

i

n T

h

e r

m

o_{p h}

i

l

i

c A n a e r o

b i

c D

i

_ge st

io n

(

u nde r the d ir e ctio n of Dr.

M

a rk Sobs ey

)

M

a

le

-_s

pe c

i fi

c

(

F+

)

c ol i p ha_ge s

w

e r e in v e st_{i g}ate

d

a s

i

nd

i

c ato r s of v

i

r u s

i

n a ct

i

v at

i

o n

d

u r

i

n_g the r

m

o_{p h i l i}c d i ge stio n a nd othe r the r

m

al pr o c e s s e s. B e c a u s e pathoge n

m

o nito r

in

g

i

n

s

l

u

d

_ge

i

s d i f fi c ult, c o stl y, a n d

i m

pr a ctic al,

m

ic r ob ial in d ic ato r s a r e n e eded to pr e

d ic

t

p

at

h

o_ge n r e

d

u ct

i

o n s

i

n

_C

la s s

A b io s o

l

i d

s F+ c ol i p ha_ge s a r e a _pr o

m is

in

_g c a n

d i d

ate

i

n

d i

c ato r

o

f f

e c a

l

c o nta

m in a

t

io n

a nd a s u r r o_gate

f

o r v

i

r u s r edu ctio n in wa ste tr e at

m

e nt _pr o c e s s e s. F+

R N A gr o u_{p I}, F+ R

N

A gr o up 111, a n d F

+ _D

_N

_{A p ha}

ge s we r e is o lated fr o

m m

u n

ic

i

_pa

l

s

l

u

d g

e.

In

la

b

o r ato r_y stud

i

e s the k

i

n etic s a nd e x te nt o f

i

n a ctiv atio n of gr o u_ps I a nd I I I F+ _{R N A} , a n

d

F+ D

N

A c ol i p ha_ge s

w

e r e _qu a nti fi ed a nd c o

m

_pa r ed at 5 3 "^C, a te

m

pe r atu r e u s e

d i

n

t

h

e r

m

o_p

h i l i

c a n a e r o

b i

c

d i

_ge st

i

o n . Is o

la

te s o

f

gr o ups I a n

d

I I I F+ R

N

A a nd F+ D

N

A

c ol

i

_{p h}a_ge s w e r e e x _po s ed to 5 3 "

C

in

a n a uto

m

ated, the nn o r egu lated he at

b

lo ck a n

d

t

i

te r e

d

a

ft

e r

0

, 5 a n

d

6 0

m i

n ute s.

A f

te r

6 0 m i

n u te s at 5 3 °

C

, F+ R

N

A gr o up I I I c o

l i

p

h

age s we r e

i

n a ct

iv a

ted si gni fi c a nt_{l y g}r e ate r

₍

P < 0 0 0 1

₎

tha n the F+ _{R N A}

gr o u_p I a n

d

F+ D

N

A

c o

H

_{p h}a_ge s. T he

in a c

t

i

v at

i

o n

k i

n et

i

c s of gr o up I I I F+ R

N

A c ol

i

p hage s r e s e

m b l

e tho s e o

f

s o

m

e e nte r

i

c v

i

r u s e s a n

d

s o

m

e othe r _patho_ge n s T he r e s ults of th

is

stu

d

_y elu c

i d

ate the

t

h

e r

m

al pr o_pe rtie s of the

m

ale-_s

pe ci fi c c o

l i

_{p h}a_ge s ub gr o u_ps a nd

f

a c

i

l

it

ate the dev e

lo

_p

m

e nt o

f

t

i m

e a n

d

te

m

_pe r atu r e r e

l

atio n sh

i

_ps t

h

at _pr e

d ic

t e nte r

i

c v

i

r u s a n d othe r _patho_ge n r e

d

u ctio n s

i

n

A C

K

N

O

W

L E D

G

E

M

E N T S

I wo ul d l i ke to tha nk Br o

w

n a nd Cal d w el l fo r fu nd in_g of th is _pr o

j

e ct a nd the

Colu

m

bu s

(

G

e o r_g

ia

) W

ate r

W

o rks fo r its s u_{p p}o rt. I

w

o ul d als o l

i

ke to t

h

a nk Dr

.

M

i

cha el

A itke n , Dr

M

i

n a

Sh

e

h

e e,

N i

c o

l

e v an

A b

el,

K i m

be r

l

y B la uth, a n

d

P

h i l l i

p

C

r u nk

f

o r

h

e

l

p

w i

th

the

C

B F T 3 pr o

j

e ct a nd D o u_g

W

ait, D r. Ja n V in

j

e

, T i in a Pa s a n e n, a nd S

j

o n Oude

j

a n s fo r their

hel p w ith the s e r ot_{y p}

i

n_g, P C R, R T

-P

C

R, a n

d

R L B H y

b

r

i

d

i

z atio n pr o c e

d

u r e s.

T A B L E

O

F C

O

N T E N T

S

Pa_ge

L I S T O F F I G

U

R E S vi

L I

S

T

O

F F I

G

U R E

S

v

i

L I

ST

O

F A B B R E V I A T I

O N S

v

i i

I I

N

T R

O

D U

C

T I

O N

1

G e n e r al O b

j

e ct

iv e s

5

S pe ci fi c O

b

_j

e ct

iv

e s 5

I I R E V I E

W

O

F T H E L I T E R A T U

R

E 7

Pri

m

a r_y a n

d S

e c o nda r_{y T}r e at

m

e nt a n

d

the

C

r e at

i

o n of S lu_{d g}e 7

T he r

m

o_p

h i l i

c An a e r o

b

ic D

i

_ge stio n 9

C

la s s A B

io s o

l

i d

s a nd L a n

d A

_{p p U}c atio n o f Sewa_ge S lu_{d g}e 1 2

Pote ntial E

ff

e cts of Patho_ge n s 1 4

V ir u s

I

n a ct

i

v at

i

o n

K i

n et

ic s

1 8

Ba cte r

i

o_p

h

a

_g

e s a s Ind

i

c ato r s of Tr e at

m

e n t o

f C

la s s A B io s o l i ds 2 2

L

i

te r atu r e R e v

i

ew

C

o n clu s

i

o n s 3 5

I I I

M

A

T E R I A L

S

A N D

M

E T H

O

D

S

3 6

Ex_pe r

i m

e n_ta

l

D e si gn 3 6

T he r

m

o_p

h i l i

c An a e r ob

i

c D i ge ste r

(

T

A

D

)

3 9

M

ale-S p_{e c}

i fi

_c

C

_o

l i

p ha_ge An a_{l y}s

i

s fr o

m

M

u n ic_{i p}a_{l S l}ud ge 4 2

M

ale-

S

pe c

i fi

c

C

ol

i

_p

h

a_ge

_C

ha r a cte riz atio n 4 5

Lab Sc ale _He at In a c

fi

v atio n Ex_pe r

i m

e nts o n Co _{l i p h}a_ge s 5 2

I V R E

S

U L T S 6 1

T he rmo_{p h i}

l i

c A n a e r ob ic D i ge st

io n

Ex_pe ri

m

e nts 6 1

M

ale-

S

pe ci

fi

c

C

ol

i

_{p h}a_ge

C

ha r a cte riz a

fi

o n 6 8

La

b Sc a

le T he r

m

a

l

In a ct

iv a

fi

o n Ex_pe ri

m

e nts o n F+

_C

_ol

_i

p ha_ge Is o late s 7 2

R

e s u

lt

s

Su

m m

a r_y

8 3

V D I S

C U

S

SI

O N

8 5

T he r

m

o_p

h i

l

i

c

A

n a e r o

b i

c D

i

_ge s

fi

o n Ex_pe

ri m

e nts 8 5

Is olate

C

ha r a cte

ri

z atio n 8 8

Lab

Sc a

le In a c

fi

v at

i

o n Ex_pe

ri m

e nts

9

1

V I C

O N

C L U

S

I

O N S

9 6

A P P E

N

D I

C

I E

S

9 8

L I S T

O

F T

A

B L E S

Pa

_g

e

T a

b

le 1 Patho_ge n a nd In d

ic a

to r

C

rite ria fo r C la s s

A

B io s ol

i

ds 1 3

T ab le 2. Ente

ri

c

V i

r u s T

h

e r

m

al In a ct

i

v at

i

o n

C

ha rt

18

T a

b

le 3

C

ha r a cte

ri

stic s o f

S

lu

d

_ge So u r c e s

U

s ed

i

n the

C

B F T^ Pr o

j

e ct 3 7

T ab le 4 R T -P

C

R T h

e r

m

o c_yc

le r

Pr o _gr a

m

4

9

T a

b

le 5.

M

a ste r

M

i

x Co

m

po n e nts fo r P

C

R Re a ctio n s 50

T ab

le

6 P

C

R T he r

m

o c_yc

l

e r Pr o_gr am 5

0

T ab le 7.

C

o n c e ntr atio n

(

Lo gi o/ g T

S

)

a nd R edu ct

io n s o

f

M

a

le

-

S

pe c

i fi

c

C

ol

i

_{p h}a_ge s

b

_y

Tr e at

m

e nt in the

C

o nt

i

n u o u s D i ge ste r

6 3

T ab le 8.

C

o n c e ntr at

i

o n s

(

Log l

0

/ g T

S

)

a nd Re

du c

t

i

o n s o

f

M

a

le

-

S

pe c

i fi

c

C

ol

i

_p

h

a_ge s T r e at

m

e nt

i

n t

h

e Batc

h

Re a cto r

6 4

Tab le 9 B e st-fi _t P_{a r a}

m

_et

e r s

f

o r In a ct

iv a

fi

o n o f

M

ale

-s_pe ci

fi

c

C

ol

i

_{p h}a_ge s

6 7

Tab le 1 0 F+ D N A a nd F+ R N A Is olate s fo u nd

i

n Fe ed a nd Batch Sam p le s

6 9

Tab le 1 1 F+ _{R N A S}e r ot_{y p}e s

f

o u n

d i

n Fe ed a nd Batch

S

a

m

_{p l}e s 7

0

Tab le 1 2 F+ D N A Ge n ot_{y p}e s

f

o u n

d

in Fe ed

S

a

m

_{p l}e s v

i

a R L B

-H y

b

ri d iz at

i

o n 7 2

Tab le 1 3

M

ale

-Spe ci fi c Col

i

_p

h

a_ge Lo_gjo Redu ctio n s in La

b Sc a

le

L I S T

O

F F I

G

U R E S

Pa_ge

F

i

_gu r e 1 F

i

r st-

O

_r

d

_{e r} K

i

_{n e}ti_{c s} 1 9

F

i

_gu r e 2. T w o

-Po_pu lat

i

o n

M

odel

K i

n etic s 2 1

F i gu r e 3 Crite ria fo r

_S

ele ctio n of

M

ic r obe s

i

n B

i

o s o l i ds o r

W

a stewate r a nd Crite ria fo r a n

I

d

e al In d

ic a

to r 2 5

F i gu r e 4. Co n c e ntr atio n s of

M

ale

-S pe ci fi c Col i p ha_ge s a s a Fu n ctio n of T i

m

e in In a ctiv atio n Rate Ex_pe ri

m

e nts at

(

a

)

5 1 °

_C

a nd

₍

b

₎

5 3 °

C 6 7

F

i

_gu r e 5. Logi o Redu ct

i

o n s of

M

ale -

S

pe c

i fi

c

C

ol

i

_{p h}a_ge

I

s olate s afte r

6 0 m in u

te s at 5 3 °

C

.7 4

F

i

_gu r e 6 Lo_gi o Re

d

u ct

i

o n s o

f

M

a

l

e-

S

pe c

i f

i c

C

o

l i

_p

h

a_ge _Is o

la

te s a

f

te r

6 0 m in u

te s at Ro o

m

T e

m

_pe r atu r e 7 5

F i gu r e 7. Lo

gi o Redu ctio n s of

M

ale-

S

pe ci

fi

c

C

o l

i

_{p h}a_ge Is olate s Du e to He at

₍

5 3 °

C Onl y 7 5

F

i

_gu r e 8 In a ctiv atio n of Gr o u_{p I}

₍

M

_S2

₎

F+ R

N

A Co_{l i p h}a_ge Fe ed Is olate I l lu str atin_{g F i}r st

-O

rde r

K i

n e

fi

c s 7 7

F i gu r e ₉. In a ctiv a

fi

o n of Gr o up I I I

( Q|

S

)

F+ R N A Col i p hage Fe e

d

Is olate 7 8

F i gu r e 1 0 In a ct

i

v atio n Su

m m

a r_{y G}r o u_{p I}

(

M

S 2

₎

Fe ed, Batch, a nd Co ntr o l Is olate s at 5 3 "

C

f

o r 5 a n

d 6

0

m in u

te s 8 0

F

i

_gu r e 1 1 In a ct

i

v at

i

o n

Su

m m

a r_y

G

r o u_{p I I I}

(Q/3

Fe ed a nd

C

o ntr o

l

s Is olate s at 5 3"

C

fo r 5

a n

d

6 0

m i

n ute s

8

1

F i gu r e 1 2 In a ctiv atio n Su

m m

a r _{y F}+ D N

A

Col i p ha_ge F

i

el d a n d

C

o ntr ol Is olate s at 5 3 °C fo r

L I S T

O

F A B B R E V I

A

T I

O

N S

A

N

O V

A

= _{a n al ys}

_i

_{s of v a r}

_i

_{a n c e}

B

O

D = b

i

olo_{g i}c al o x_{y g}e n de

m

a n

d

b

_p = _{ba s e}

pair s

C

=

_C

_{elsiu s}

C

B F T =

_C

olu

m b

u s Bi o s o

l i d

s F

l

ow T hr o u_g

h

T he r

m

o_{p h i l i}c Tr e atme nt

C

F R =

C

ode o

f

Fe

d

e r al Re_gu

la

t

io n s

C

F

U

= _{c o}

_l

_{o n}

y

f

o rm in_g u n

i

t D

N

A = d io x_yri bo n u cle_ic a ci d E c oli = Es cher ich ia c ol i

E P A = En v ir o n

m

e n tal Pr ote ct

i

o n

A

_ge n c_y

F+ =

m

ale

-s_pe ci f ic c ol i p ha_ge

F+ D

N

A =

_m

ale-_s

pe ci

fi

c D

N

A c o_{l i p h}a_ge F+ R N

A

=

_m

_ale-_s

pe c

i fi

c R N A c ol

i

_{p h}a_ge F

C

= _{fe c al c ol}

_i

_{fo r}

_m

_s

g = gr a

m

s

m

l -

_m

_{i l l i}

_h

_te r s

M

P N =

_m

_{o st}

pr oba

b

le n u

m b

e r

N H

3 = a

m m

o n

i

a

N R = n o r e

m

o v al

O

W

A

S

A =

O

r a n _ge

W

a_te r a n

d Se

we r

A

utho r

i

t_y P B

S

=

p ho s_p

h

ate

b

u

f f

e r s olu_t

i

o n P

C

R =

po_{l y}

m

e r a s e cha

i

n r e a ct

i

o n

P

F

R P = _pr o c e s s e s to fu rthe r r e

d

u c e _pat

h

o_ge n s

P F U = _{p l}a_qu e fo r

m

in _g u n it

P

O

T

W

= Pu

b

l icl y

O

w n e

d

Tr e atme nt

W

o r

k

s

R L B = _{r e v e r s e l in e b lot}

R

N

A = _r

_{i b}

_{o n u c le}

_i

_{c a c}

_{i d}

R P

M

= r otatio n s _pe r

m i

n ute

R T-P

C

R = r e v e r s e tr a n s c ri pta s e

-pol y

m

e r a s e chain r e a ctio n

SC

W

R F = So uth

C

olu

m b

u s

₍

G

A

) W

ate r Re s o u r c e s Fa ci l it_y

SS

= _{s u s}

pe n

d

e

d

s ol

id

s

s s-D

N

A =

s

in

_{g l}e str a n_ded D N A

s s-R

N

A =

s

i

n_{g l}e str a n

d

ed R

N A

T A D = the r

m

o_p

h i l i

c a n a e r o

b i

c

d i

_ge stio n

T N T

C

= to o n u

m

e r o u s to c o u nt

T

S

= total s ol i

d

s

T

SB

= tr_{y p}t

i

c s o_y

b

r ot

h

W

S SL D

=

_W

_{e ste r n L a}

_k

_{e Su}

pe r

io r

Sa nita r_{y D}

i

str

i

ct

p X=

m

ic r ol

i

te r s

I I N T R

O

D U C T I

O

N

In the

U

n

i

ted State s, the fi r st c o

m

pr ehe n siv e s a nita ry s ewe r system wa s n ot

c o n str u cte

d

u nt

i l

1

8

5 5

₍

in

C h i

c a_go

)

a nd t

h

e

f

i r st s e

w

a

_g

e tr e at

m

e nt

f

a ci l it_y

i

n 1 8 8

6

₍

N

e

w

Yo rk

C

it_y

)

.

Cu r r e n

tl y the r e a r e o v e r 19,4 0 0

m

u n

i

c

i

pal Pub l

ic

l y

O

w n ed Tr e atme nt

W

o rks

(

P O T

W

s

)

in

the

U S

.

, tr e ating r o u g h l y 5 0 b

il l

i

o n

m

^

of r aw s ewa_ge a _ye a r

(

N A S, 1 9 9 6

)

As

the s ewa_ge is tr e ated, it go e s thr o ug h a s eri e s of pr o c e s s e s that r edu c e the c o n c e ntr atio n of

the e a s

i

l y-

d

_{e c o}

m

po s ab le o r

_g

a n

i

c

m

ate r

i

als a n

d

_patho_ge n

i

c o r_ga n

is

m

s Se

w

a_ge slu

d

_ge

i

s the

m

ate r

ia

l b

efo r e

it

r e c e

iv e s

b

io

lo

_g

i

c a

l

o r che

m i

c al tr e atme nt a n

d b i

o s ol

id

s a r e the _ge n e r al l y

s et t

l

e a

b l

e s o

li d b i

o

lo

_g

i

c a

l

r e s

i d

u a

l

_pr o

d

u c e

d d

u r

in

_g the tr e at

m

e nt o

f

s ew a_ge w a stewate r. It

is

ofte n a

m

ixture of hu

m

a n a n d indu str

i

al w a ste s a nd

m

a_y c o n sist of n o

m

o r e than 1

%

of the

w a stewate r f low .

C

ha r a cte r

i

st

i

c s o

f

t

h

e slu

d

ge depe n d o n the w a stewate r tr e atme nt pr o c e s s

a n

d

s

lu

d ge tr e at

m

e nt

₍

E

b

e rle et al 1 9 9 4

)

.

T he in stal latio n a n d o_pe r at

i

o n o

f

w a stewate r tr e atme nt

f

a ci l itie s c o ntri bute

s

i g

n

i f

i c a nt_{l y t}o _pol

l

ut

io n

r e

d

u ctio n, pr e v e nt

i

o n o

f d

amage to the e n v

i

r o n

m

e nt, a n

d

pr o te ct

io n

of pu

b

l ic he alth. How e v e r, the

d

is cha rge of s ew age slud ge, w hethe r tr e ate

d

o r n ot, c a n c r e ate

s e rio u s

w

ate r _po

l l

utio n _pr o

b

lem s in the r e c eivin_{g b}od y of w ate r o r la nd Raw s ewa_ge o

f

te n

c o nta

i

n s

m

a n_{y p}atho_ge nic o r_ga n

is

m

s, w h ich

is a

gr e at pote ntial pu

b

l ic he a

l

th c o n c e r n .

A d

d i

t

io n a

_{l l y}, the h

i

g h c o n c e ntr atio n s o

f

s u spe nde

d

s o l i ds

(

S S

)

a nd n utri e n ts, a s w el l a s the

o r_ga n

ic

m

at te r

₍

e _g., B

O

D

)

o

f

r aw s ewage,

m

ay c r e ate e utr op h

i

c at

i

o n pr o

b l

e

m

s. T he

c o

m m

o n

m

et hods

f

o r

fi

n al d

is

_po s al of s

lu

d

g

e a r e la n d

fi

l ls

, la n d ap p

l

ic a

ti

o n, a nd

i

n c

in e r a

ti

o n

(

Z ho u a nd

M

a v in

ic

2 0 0 3

₎

S lud ge in cin e r ati o n

fi

r e s slu_{d g}e at _{h i g h} tem pe r atu r e s in a c o

m

bu sto r. In cin e r at

io n

is

c o st

l

_y a n

d

e n e r_{g y}

i

nte n s

i

v e It _pr o

d

u c e s o

f f

-ga s that n e eds to be r e_gu lated

₍

e _g

h

_y

d

r o c a r

b

o n s, a n

d

c a r

b

o n

m

o n o x

i de

)

Sl

u

d

ge

d is

po s al to la n

d fi

l

ls

,

m

o stl y

d i

spo s e

d

a

l

o n g

w ith mu nici pal s o

l i

d

w

a ste s, r e s ults

i

n

d i f

fi c ultie s in c o

m

pr e s s

io n

of d

i

spo s ed

m

ate rials. T he

c a_pa c

i

tie s of e x istin_{g l}a n d

fi

l

l

s a r e

di m in

is

h

in

_g; ho

w

e v e r, the a

m

o u nts o f slud ge a n

d d i

spo s al

c o sts c o nt

in u e

to

in c r e a s e

It

is

m

o r e a n

d m

o r e d

i f fi

c ult to

fi

n

d

a_{p p}r o_pr

ia

te a n

d

a

d

e_qu ate n ew

s

i

te s

f

o r la nd

fi

l ls

₍

Z

h

o u a nd

M

a v

in

i

c 2 0 0 3

₎

It

i

s r e c o

_g

n

iz e

d that

b

e n e

fi

cia

l l

a n

d

a_{p p l i}c atio n

₍

e _g a_gr

i

c u ltu r al s o

i l

c o nd

i

t

io n

i

n _g o r

fo r e st fe rti l izin _g

₎

of pr o c e s s ed slu_{d g}e

₍

b io s ol i ds

₎

is a c o st

-ef fe ctiv e a nd e n v

i

r o n

m

e ntal l y

s u sta

in a

b

l

e o_pt

io n

, be c a u s e n utr

i

e nts a n

d

o rga n ic mat te r a r e r e cycle

d

to s o

i

ls In 1 9 9 3 the

U S E PA r ele a s ed the te chnic al sta nda rds

(

4 0 C F R Pa rt 5 0 3

₎

fo r the u s e a nd d

i

s_po s al of

b i

o s o

l i d

s, a n

d i

ntr o

d

u c e

d

the c r

i

te r

i

a

f

o r

C

la s s -A

b i

o s o

h d

s

C

la s s-A

b i

_{o s o}

l i d

s a r e e s s e nt

ia

_{l l y}

patho_ge n

f

r e e, me et a c c epta

b

l y low

m

eta

l

c o n c e ntr at

i

o n s a n

d

v e cto r at tr a ct

io n

r e

du c

t

io n

r e_qu

ir e

m

e nts, a nd c a n

b

e

b

e n e

fi

c

i

a

l l

y la nd

-a_{p p}

h

ed w

it

ho ut r e strictio n s

(

U

S

E P A 19 9 9_; N A

S

2 0 0 2; Z ho u a nd

M

a vin ic 2 0 0 3

₎

T he s e r e_qu

ir e

m

e nts a r e

m

et thr o u_{g h P}r o c e s s e s to Fu rthe r

Redu c e Patho_ge n s

₍

P F

R

Ps

)

, w h

i

ch tr a n sfo r

m

slud ge fr o

m

wa ste pol luta nts w ith h i g h le v els

of patho_ge n s

i

nto a v alu ab le

b i

o s o l

i d

s r e s o u r c e

(

Z ho u a nd

M

a v

in

ic

2 0 0 3

)

.

P F R Ps that a r e c u r r e ntl y r e c o_gn

i

z e

d b

_y the

E

P A a r e c o

m

_po st

in

_g,

h

e at

d

ry

in

g,

h

e at

tr e at

m

e nt, the r

m

op h i l ic a e r o

b

ic

d

i ge st

i

o n,

b

eta r ay

i

r r a

d

iatio n,

g

a

m m

a r ay

i

r r ad

i

atio n , a n

d

pa ste u r

i

z a

ti

o n

W

he n the s e

_p

r o c e s s e s a r e o_pe r ated u sin_g s_pe c

i fi

e

d

c o n

d

i t

i

on s, pathoge n

i

c

(

U S E P A 1 9 9 9;

N A

S 2 0 0 2

)

. D e sp ite the pote ntial fo r the r

m

op h i l ic a n a e r ob ic d i ge stio n to

m

e et

C

la s s A c rite r

i

a, th

i

s pr o c e s s is n ot c u r r e nt

l

y r e c ogn

i

z e

d

a s a P F R P to pr o

d

u c e

C

la s s A

B io s o l i ds.

In a

d

d

i

t

i

o n to the _patho_ge n r e_qu

i

r e

m

e nts.

C

la s s A b

i

o s ol

i

ds

m

u st be

m

o n

i

to r ed fo r

i

nd ic ato r o r_ga n

i

s

m

s, fe c al c ol i fo r

m

, o r

S

al mon el la sp p ba cte ria

(

1

)

at the ti

m

e o f u s e o r

d i

s_po s al;

(

2

)

at the t

i m

e t

h

e

b i

o s ol i

d

s a r e _pr e_pa r ed fo r s ale o r _{g i}v e n aw a_{y i}n a ba_g o r othe r

c o nta

i

n e r

f

o r la nd a_{p p l i}c at

i

o n_; o r

(

3

)

at t

h

e t

i m

e the

b i

o s ol

i

ds a r e _pr e_pa r ed to

m

e et t

h

r e e

r e_qu

i

r e

m

e nts fo r " e x c e_pt

i

o n al qu al it_y" slud ge to e n s u r e that _gr ow t h o

f b

a cte r

i

a

h

a s n ot

o c c u r r e

d

(

U

S

E P A 1 9 9 9

)

M

u n

i

ci pal

i

t

i

e s a nd P

O

T

W

s t_{y p}

i

c al l y r e

l

_y o n a s s a_ys o

f i

n d

i

c ato r

m i

c r o o r_ga n

i

s

m

s to

d

ete ct _patho_ge n r e

d

u ct

i

o n s o r e x c e s siv e

m

ic r o

b i

a

l

c o nta

m i

n at

i

o n o f pu

b l i

c

he alth c o n c e r n

To _pr ote ct t

h

e

_p

u

b l i

c '

s

h

e a

l

t

h

a n

d

to s a v e t

i m

e a n

d m

o n e_y,

i

t

i

s

i m

pr a ct

i

c a

l

to

d i

r e c t

l

y

m

o nito r,

i

de nti f y, o r e n u

m

e r ate the hu n

d

r eds o f pat

h

oge n

i

c

m i

c r o o rga n is

m

s a s s o c

i

ated w ith

f

e c al po

l l

ut

i

o n .

O

v e r 1

4 0

v

i

r al pat

h

oge n s

h

a v e

b

e e n

i d

e nt

i fi

e

d f

r om

h

u

m

a n

f

e c e s

, n ew o n e s

c o ntin u e to be d

i

s c o v e r e

d

a nd it is bel ie v ed that the r e a r e

m

a n_y ot

h

e r s st

i

l l u nkn own

₍

Ga ntz e r

et al 1 9 9 8

₎

.

W

h

i

le

m

etho

d

s ha v e

b

e e n

d

e v elope

d

fo r dete ct

i

ng a n

d

a s s ay

i

n g spe ci fi c v

i

r u s e s

o r vir u s _gr o u_ps, they a r e ofte n e xpe n siv e, te chn

i

c al l y

d

e

m

a nd

i

n g, a n

d

t

i m

e

-c o n s u

m i

n _g A

l

s o,

v

i

r u s e s a r e ofte n _pr e s e nt

i

n low but st

i

l

l

risk y c o n c e ntr at

i

o n s, w h

i

ch

m

ay r equ

i

r e t

h

e a n al ys

i

s

of la r_ge s a

m

_{p l}e v olu

m

e s, s u ch a s

m

o r e tha n te n l ite r s of wate r o r mo r e tha n 10 0

m

l of slud ge.

T

h

e u s e of

i

nd

i

c ato r s e ntai ls _qu a n t_{i f y i}n _g

m

o r e _{p l}e nt

i

ful m

i

c r o

b

e s that c o

m m

o n

l

_y

i

nha

b i

t the

i

nte st

i

n e s o

f

wa r

m

-b l_{o o}

d

_ed _{a n}

i m

_al_{s a n}

d

_{c o n s}i d_{e r}i_n

g the

m

a si gn that

m

o r e ha z a rdo u s

C

u r r e nt_{l y}

f

e c al c ol i fo r

m b

a cte r

i

a a r e t he sta nda r

d m

ic r o

b i

al

in

d i

c ato r u s e

d i

n the

U

nited State s fo r b io s ol i ds a nd

m

u nic_{i p}al

w

a ste wate r H owe v e r , be c a u s e vir u s e s a r e s

m

al le r

a nd a r e

m

o r e r e sista nt to in a ctiv atio n _pr o c e s s e s tha n ba cte ria, fe c al c ol i fo r

m

s a r e c o n si de r ed

i

n a

d

e_qu ate

i

n

d i

c ato r s o

f

wate r

b

o

m

e e n te r

ic v

i

r u s e s

(

s u c

h

a s He_patitis A v

ir u s

, Rota viru s e s,

a n

d

A de n o vir u s e s, a nd s

m

al l, r o u nd str u ctu r e

d

"

ga str o e nte r

i

t

i

s v

i

r u s e s "

s u ch a s Astro viru ses

a n

d N

or o vir u s e s, in clud

i

n g

N

o rwa

l k

v

ir u s

) (

H a v ela a r 1 9 9 3

)

.

Ente r

i

c

b

a cte r

i

o_{p h}a_ge s, vir u s e s

i

n

f

e cting e nte r

i

c ba cte r

i

a, ha v e

b

e e n pr opo s e

d

a s

m

o r e

r el iab le ind ic ato r s

f

o r hu

m

a n v

i

r a_{l p}atho_ge n s

₍

_G

e rba 1 9

8

7_; Le cle r c et a

l

. 2 0 0 0

)

. Col i p hage s ,

v

i

r u s e s w h

i

c

h i

n fe ct Es c

h

e r ich ia c o

l

i, ha v e pr o

b

a

b

le fe c al o r

i

g

in s

, a r e c o n s

is

te ntl y

f

o u n

d i

n

s ew a_ge, a nd a r e a

l

s o e a si l y, quick l y, a nd in e xpe n siv e

l

y qu a n t

i fi

ab le.

T

h

e r e a r e s e v e r al d

i f f

e r e nt ta x o n o

m

ic _gr o u_ps o

f

e nte r

ic

ba cte rio_p

h

a_ge s, n ot al l of

w h ich

m

a_{y b}e _go od vir u s ind ic ato r s. Ba c te r

i

op hage s t

h

at

i

nfe ct their ho sts thr o u

g h r e c e_pto r s

o n the c el l w al l a r e " s o

m

atic " "

M

a

l

e-_s pe ci

fi

c

"

c ol i p ha_ge s

i

n fe ct their ho sts thr o u_{g h}

r e c e_pto r s o

f

_{F p}

i l i

, w

h i

ch a r e s u rfa c e ap pe n

d

age s e n c o

d

e

d b

y F

-p

l

a s

m i d

_ge n e s. T

h

e s o

m

at

ic

c o

l i

_{p h}a_ge

f

a

m i l i

e s

in c

lude

M

_yo viri

d

a e,

M

ic r o v ir i

d

a e,

S

ip

h

o viri

d

a e

(

o r

S

ty

lo v

iri

d

a e

)

a nd

Podovir i da e Le viviri da e a nd In o vir _{i d}a e a r e

m

ale

-s_pe c

i

fi c c ol

i

_{p h}a_ge fa

m i

l ie s w h ich c o nta

i

n

R N A a n d D

N

A ge n o

m

e s, re spe c tiv el y F

+ _R

_N

_A c ol i p ha_ge s c a n be s ub d iv

i

ded fu rthe r into

fo u r _gr o u_ps : _gr o u_{p I}

₍

M

S 2

₎

, gr o up I I

(

G A

)

, gr o up I I I

(

Q

jS

)

, a nd gr o up I V

(

S P

)

D i f fe r e nt

p

e r s

i

ste n c e o

f

_{p h}a

_g

e s

in

the e n v

ir o n

m

e nt

is s u

_{g g}e ste

d

to be r elate

d

to _p

h

a

_g

e

m

o r_p

h

olo_{g y}

(

La s o

b

r a s et a

l

1

9 9

7

₎

It

i

s t

h

o u_g

h

t that t

h

e _p

h

_ys

i

c al str u ctu r e, c o

m

po s

i

t

io n

a n

d m

o rp holog y

of F+ R

N

A p ha_ge s c lo s e

l

_y r e s e

m b

le t

h

o s e of hu

m

a n e nte r

i

c vir u s e s T he e xte nt to

w

h ich

c o

l i

_p

h

a_ge s a r e r e

l ia

b l

e

in

d i

c ato r s o

f p

at

h

o _ge n r edu ct

io n s

_{b y} slu_{d g}e tr e at

m

e nt _pr o c e s s e s s u c

h

G

e n e r al

O

b

_j

e ctiv e s

T

h i

s stu

d

_y e x a

m i

n e

d m

ale

-s_pe c

i f

i c

₍

F+

₎

c o l

i

_{p h}a_ge

in a c

tiv at

i

o n

i

n a

la

b

-_{s c a}l_e

t

h

e r

m

o_p

h

i l ic a n a e r o

b

ic

d i

_ge ste r a n d the _pote ntial u s e of the s e _{p h}a_ge s a s a n in d ic ato r of

patho_ge n r edu ctio n in the r

m

al pr o c e s s e s to

m

e et C la s s A b io s ol i d r e_quir e

m

e nts Be c a u s e of

obs e r v e

d b i

-p

h

a sic

i

n a ct

i

v at

i

o n

k i

n et

i

c s

i

n the r

m

o_{p h}

i

l ic a n a e r o

b i

c d

i

_ge stio n stud

i

e s

(

A itke n

et al. 2 0 0 3

)

, F+ c ol

i

p hage s in r aw a nd tr e ated slud ge s we r e fu rthe r cha r a cte riz ed a s eithe r F+

D N A o r F+ R

N A

, a n

d

t he F+ R

N

A c o l

i

p

h

age s we r e fu rthe r

i d

e nt

i fi e

d

a nd cha r a cte r

i

z ed a s to

w h

i

c

h

_gr o u_p the_y

b

e

l

o n _ge

d

G

r o u_ps I a n

d

I I I F+ R

N

A a n

d

F+ D N A c o

l i

_p

h

a_ge s

w

e r e

i

s olated

a nd cha r a cte riz e

d

fr o

m

the u ntr e ated slud ge

(

fe ed

)

, the rmop h i l ic al l y d i ge sted slu

d

ge fr o

m

a

c o nt

i

n u o u s

fl

ow r e a cto r, a n

d f

r o

m

t

h

e

b io s o

l

i

ds e xpo s e

d

to a the r

m

op

h i

l

i

c te

m

pe r atu r e

f

o r

v a rio u s _pe r

io

ds of t

i m

e

in

the

b

atch r e a cto r. Be c a u s e of e v

i

de n c e that the s e c ol i p hage s

m

ay

p

o s s e s s

d i f

fe r e nt

h

e at s e n s

i

t

i

v

i

t

ie s

, t he

i

s o

l

ate s w e r e

f

u rt

h

e r e v alu ate

d fo r

i

n a ct

i

v at

i

o n

k in etic s

i

n a la

b

-s c ale he at e x_po s u r e e x_pe r

i m

e nt at 5 3 "C

f

o r 5

m

in ute s a n

d

6 0 m in ute s.

S pe ci f ic

O

b

j

e ct iv e s

1

E

v a

l

u ate t

h

e

i

n a ct

iv a

t

io n

o

f m

ale

-s_pe c

i fi

c c o

l i

_p

h

a

_g

e s

b

_{y t h}e r

m

o_p

h i l i

c a n a e r o

b i

c

d i

_ge stio n

₍

T A D

)

i

n c o ntin u o u s fl ow a nd batch r e a cto r s at 5 1, 5 3, a nd 5 5 "

C

2. Dete r

m i

n e the

i

n a ct

i

v atio n k

i

n et

i

c s of

m

ale -_s

pe c

i f

i c c o l i p ha_ge s at the r

m

o_{p h}

i

l

i

c

te

m

_pe r atu r e s

i

n

b

atch e x_pe r

i m

e n_ts.

3. Is o

l

ate

i

n

f

e ct

i

o u s

m

a

le

-_s

p

e c

i fi

c c ol

i

_{p h}a_ge s fr o

m

u ntr e ate

d

s

l

u

d

_ge a n

d

tr e ated

4.

G

enoty pe a n

d

/o r s e r oty pe F+ D

N A

is olate s a s F d,

M

l 3, o r C H and F+ R

N A

is olate s

a s _gr ou _{p I}, I I, I I I, o r I V .

4 Ev alu ate F+ _R

_N

_A a n

d

F+ D

N A

c o l

i

_p

h

a_ge s e n s

i

t

i

vit_y to 5 3 °

C

fo r 5

m i

n ute s a n

d

6 0

m i

n ute s

5 C ha r a cte riz e t

h

e

i d

e ntitie s of the he at-_{r e s}i_{sta nt a n}d h_{e at}-_{s e n s}

i

_t

i

_{v e}

m

_a

l

_e-_s pe c

i f

i c

ba cte r

i

o_{p h}a_ge

f

r a ct

i

o n s o c c u r rin _{g i}n in a ctiv atio n r ate e x_pe r

im

e nts

i

n the _{d i g}e sted

b io s ol i ds

6. Dete r

m i

n e

i f

pa rt

i

c ula r gr o ups o r ty pe s o

f

F

+ _R

_N

_{A o r F}+ _{D N A c ol i p h}a_ge s c o ul d

s e r v e a s u s e

f

u

l i

n

d i

c ato r s o_{f p}atho_ge n r e

d

u ct

i

o n s

i

n Pr o c e s s e s to Fu rt

h

e r Redu c e

Patho_ge n s

(

P F R P

₎

ba s ed o n their in a ctiv atio n r ate s in t

h

e r

m

o_p

h

i l ic a n a e r ob ic

I I

R

E V I E

W

O

F T

H

E L I T E

R A

T U

R

E

Pri

m

a r_y a n d

S

e c o nda r_{y T} r e at

m

e n t a n d the Cr e at io n of S lud ge

W

he n r aw s ewa_ge

fi

r st a r r

i

v e s at the P O T

W

, it u s u a

l l

y

p

a s s e s thr o ug h a s c r e e nin g

d

e v ic e, c o n sisting of a s e r

i

e s of

m

etal ba r s, to r e

m

o v e la rge ob

j

e cts that ha v e e nte r ed the

s ewe r _p

i

_pe s a n

d m i

_{g h}t da

m

a_ge c o

m

_po n e nts o

f

the P

O

T

W

T

h

e s ewa_ge the n fl o

w

s

in

to a

_g

r

i

t

c

h

a

m

be r, w he r e pa rticle s r o u

g h

l y the siz e a nd de n s

i

ty o f s a n

d

gr a

in s s e

t tle o ut Re

m

o v al o

f

th is c o a r s e _grit is inte nded to _pr ote ct the _pu

m

_ps in the r e st o

f

the s_yste

m

W

ith la r _ge ob

j

e cts

a n

d

_grit thu s r e

m

o v e

d

, the s ewage is pu

m

ped to a pr

i m

a ry s et tl

i

ng ta nk o r pr i

m

a ry cla

ri f

i e r.

In a t_{y p i}c al tr e at

m

e nt _{p l}a nt,

m

u ch of the

fl

ow thr o ug h the r e st of the syste

m i

s b y gr a v ity

(

N

_{A S 19 9 6 ; L}a

w

s 2 0 0 0

)

In the _pr

i m

a r_y s et t

l

in_g ta nk, s et tle ab le o r fl o ata

b

le s ol

i d

s a r e r e

m

o v ed fr o

m

the

s ewa_ge

d

u r

i

n_g a _pe rio

d

of abo ut 3 ho u r s. T he ta nk

m

ay be c

ir c u

la r o r r e cta ngula r In a

c

ir c u

la r ta nk, the s ewa

g

e e nte r s at the c e nte r a n

d

slow l y

fl

ow s to the ed ge

w

he r e

i

t e x

i

ts

u n

d

e r a baf fl e In a r e cta n _g

l

e ta nk, the s ewage e nte r s at o n e e n

d

a nd e x

it

s at the othe r

So

l

i d

m

ate rials that fl o at to the s u r

f

a c e du r

i

n_g the r e si de n c e t

i m

e o

f

the s ew a_ge

in

the ta nk a r e

r e

m

o v ed b y a

m

e cha nic al sk

i

m

m i

n_{g d}e v

i

c e that _pu she s

fl

o atin_g o

b

j

e cts to a ho_{p p}e r, fr o

m

w h ich the_y a r e _pu

m

_ped into t

h

e a n a e r ob ic

d

i ge ste r T he bot to

m

of the ta n k

is

in cl in ed, a n

d

a

s

i m i

la r m e cha n

ic a

l de v

ic e

m

o v e s t

h

e s

l

u

d

_ge that a c c u

m

ulate s o n the

b

ot to

m

towa r

d

the

d

e e_pe st _pa rt o

f

the ta n

k

,

w h

e r e

i

t

i

s

d

r awn o

f f

a n

d

u s u al l y

i

s

p

u

m

pe

d

to t

h

e a n a e r o

b i

c

d i

_ge ste r T he

m

ate r

i

al sk i

m m

e

d

fr o

m

the s u rfa c e a nd fr o

m

the

b

ot to

m

o f the _pri

m

a r_y ta nk

i

s

i

s te r

m

e

d p ri m

a r_y s ewa_ge tr e at

m

e nt It

i

s r e

_q

u

i

r e

d b y

fe

d

e r al la

w

that a P

O

T

W

o

_p

e r at

i

n

_g

w it_{h p}

ri m

a r_y tr e at

m

e nt o n l y,

m

u st r e

m

o v e at le a st 3 0

%

of the B

O

D a n

d S S

fr o

m

the s ew a

g

e

(

Law s _{2 0 0 0}

₎

P ha_ge r e

m

o v al is fair_{l y l}ow a n d e r r atic du r

i

n _g t

h

e s c r e e n

i

n_g

, g ri t cha

m

be r, a nd

pr

im

a r_y s ed

i m

e ntat

i

o n _pr o c e s s e s He r e,

m

o st v

i

r u s e s

i

n t

h

e s e

w

age a r e r edu c ed b y s et tl ing

w

ith o n_{l y 0}-3 0

%

_ef f_{i c}

i

_en_c

y T he

m

a

_j

ori t_y of the v

i

r u s e s r e

m

a

i

n in the _pri

m

a r_y ef f lu e nt,

b

ut

tho s e e nte rin_g the slud ge c a u s e the slud ge to ha v e a h i g her vir u s c o n c e ntr at

i

o n tha n t

h

e r aw

s ewa_ge. In o n e e xpe r

i m

e nt

i

n w

h i

c

h p

hage

f

2

w

a s s e e

d

e

d i

nto t he wa stew ate r t

h

e

m

e a n

p

ha_ge r edu ctio n wa s 3 7 1

%

(

2 7 8-5 4 2

%

)

i

_n 2

.5

m

i l l

i

o n

g

al lo n s/ da

y b y pri

m

a r_y tr e at

m

e nt

(

B it to n 1 9 8 7

₎

.

I

f

s e c o n

d

a r_{y t}r e at

m

e nt

i

s u s e

d

, the ef f lu e nt

fr

o

m

t

h

e p

ri m

a ry ta n

k f l

ow s

i

nto a s e c o n

d

ta nk w

h

e r e b

i

olo_{g i}c a

l

_pr o c e s s e s a r e u s ed to r e

m

o v e

m

u ch o f t

h

e B

O

D

i

n the e

f f

lu e nt. He r e ,

o r_ga n

i

s

m

s

i

n t

h

e ta n

k

c o n s u

m

e the o r_ga n

i

c s u

b

sta n c e s

i

n the _pr

i m

a r_y e

f f l

u e nt In t

h i

s

pr o c e s s, the c o n s u

m

e r o rga n

i

s

m

s gr o

w

a n

d m

ulti p l y, w h i le la rge pe r c e ntage s of the o rga nic

s ubsta n c e s a r e r e s_{p i}r ed

A

s a r e s ult, t

h

e am o u nt o

f

pote nt

i

al l y o x

i d i

z a

b

le

m

ate

ri

a

l i

n the

w a ste is _gr e at_{l y} r edu c ed T he ef f lu e nt fr o

m

th is tr e at

m

e nt _pr o c e s s c o n sists

i

n _pa rt o

f

the

o r_ga nis

m

s that

h

a v e

b

e e n fe ed in_g o

f

f the o r_ga nic _wa ste s.

M

o st of the b io

m

a s s of the s e

o r_ga n

i

s

m

s c a n

b

e r e

m

o v e

d

b y tr a n sfe r

ri

n_g t

h

e ef

f

lu e nt

i

nto a s e c o n

d

a r_y s et t

l i

n_g ta nk o r

cla r

i fi

e r T he r e the b

i

o

m

a s s s et tle s to the

b

ot to

m

in the

f

o r

m

o

f

a

f

lo e a nd

i

s r e

m

o v ed

i

n a

m

a n n e r si

m

i la r o r i

d

e nt

i

c al to that e

m

_{p l}o_yed

i

n t

h

e _p

ri m

a r_y ta n

k

A po rtio n of the s e c o n

d

a r_y

s

l

ud ge

i

s the n r e

m

o v e

d

fo r s e_pa r ate tr e at

m

e nt a n

d

d

i

s_po s al, w

h i

le the r e

m

ain

d

e r is r e cyc

l

e

d

In the a ct

iv a

ted slud ge _pr o c e s s,

p

hage s

m

ay

b

e r emo v ed thr o u

g

h: ads o rptio n to o r

e

m

be

d

d in_{g w}

i

th in f lo e s,

in a c

tiv atio n b y s e

w

age

b

a c te ria, o r in

g

e st

i

o n b y pr oto z o a. T

h

e

s e c o nda r_y tr e at

m

e nt ste_p ef f icie ntl y in a ctiv ate s _{p h}a_ge s, n o r

m

al l y show ing gr e ate r tha n 9 0

%

r e

d

u ct

io n

of infe ctivit_y.

O

n e stud y o f p hage r e

m

o v al thr o ug h a ct

iv a

te

d

slud ge fo u nd the

ef

f

i c

i

e n c _y r a n _ge

b

etwe e n 9 6-9 7

.3

%

, w h

i

le the e nte r o v

i

r u s e s a v e r aged 9 2

%

r e

m

o v al

ef fi cie n c _y

(

B it to n 19 8 7

)

. A

d

d itio n al l y, w he n p hage s a nd E. c ol i s a

m

p le s we r e

m

o nito r ed

we ek l y fo r a o n e

-ye a r _pe r

i

od, it

w

a s d

i

s c o v e r ed that p hage s w e r e r e

m

o v ed thr o ug h a ctiv ated

slu

d

_ge _pr o c e s s e s e

f fi

cie nt_{l y} a n

d

w e r e bet te r _ga u_ge s o

f

e nte r o v

i

r u s e s t ha n w a s E. c ol i.

T he r

m

o_{p h i l i}c

A

n a e r ob ic D i ge st io n

An a e r o

b

ic d

i

_ge st

i

o n

is a

m

o n_g the

m

o st c o

m m

o n

m

ethods o

f

tr e atin _{g p}r

i m

a r_y slud ge

a n d the wa ste

b

io

m

a s s fr o

m b i

olo_g

i

c al tr e at

m

e nt _pr o c e s s e s s u ch a s a ctiv ated slud ge T he

a n a e r ob ic d i ge ste r is a clo s e

d

, u s u al l y cy l in dric al ta nk, w he r e it pr o vi de s fo od fo r a spe c

ia

l

cla s s o f

m i

c r o o r

_g

a n

i

s

m

s that c a r r_y o n t

h

e

i

r

m

eta

b

o

_{l i}

c a ct

iv

i

t

ie s

in

t

h

e a

b

s e n c e o

f

o x_y

_g

e n ,

i

.e

a n a e r o

b

ic al l y. T he pr odu cts of the a n a e r ob ic d

i

ge ste r a r e

d

i ge sted slud ge

(

b io s o

h

ds

)

, a

s u_pe r n ata nt fl u i d, a nd ga s e s T he d i ge sted slud ge is r elativ el y stab le a nd

i

n o f fe n siv e

c o

m

_pa r e

d

to t

h

e u nd

i

_ge ste

d

_pr

i

ma r_y a n

d

s e c o n

d

a r_y slud ge s. Fu rthe r

m

o r e

, its v olume is o nl y

abo ut o n e-th i_r d t

h

_at _of th_e

pr

i m

a r_y a n

d

s e c o nda r_y slu

d

_ge s T

h i

s r edu ctio n

in

v olu

m

e

i

s

a ch

i

e v e

d

both

b

_y t

h

e c o n v e r s

io n

of s o

m

e of the o r

_g

a nic s in the r aw slu d ge to _ga s e s,

(

p

ri m

a r

i l

_y

m

et

h

a n e a n

d

c a r

b

o n

d i

o x

i d

e

₎

,

b

y a n a e r o

b i

c c ata

b

o

l i

s

m

, a n

d b

y

d

ew ate r

in

g

t

h

e

slud ge to r edu c e

i

ts

m

o

i

stu r e c o nte nt. T he r a

w

slu

d

ge ty p ic al

l

y ha s a

m

o

i

stu r e c o nte nt o f 9 4

-9

9

% b

_{y w} e

i

_g

h

t

₍

1-

6

T he a n a e r ob ic d i_ge ste r

i

s in v a riab l_y he ated to s_pe ed u_p the

m

eta_bohc r ate o f the

m i

c r obe s Fo r

m

e s o_{p h}

i

l

i

c a n a e r o

b i

c d

i

_ge st

i

o n, ope r at

i

ng te

m

pe r atu r e s a r e u s u al l y

i

n the

r a n_ge of 2 7-3 5 °C

. Fo r the r

m

o

p h i l ic a n a e r ob ic d i ge stio n, ope r atio n te

m

pe r atu r e s a r e betw e e n

5

0 a n

d

7 0

°

C

, a

lt

h

o ug h u s u al l y t

h

e

m

a x

i m

u

m

te

m

pe r atu r e

i

s n o

m

o r e tha n 6 0 °

C

₍

Z

h

o u a n

d

M

a vinic 2 0 0 3

₎

T he

m

etha n e _ga s _pr odu c ed in the _{d i g}e ste r is ade_qu ate to _pr o v i de

_f

u el to he at

t

h

e d i ge ste r to the de sired te

m

_pe r atu r e T he e x c e s s

m

etha n e _pr odu c ed

i

n the d i ge ste r is

b

u r n e

d

e

i

the r a s a wa ste _pr o

d

u ct o r o

f

te n c o u_p

l

e

d

to the _pr o

d

u ct

i

o n o

f

e

l

e ctr

i

c

it

_y. T

h

e

s u_pe r n ata nt f lu

i

d

f

r o

_m

the

d i

_ge ste r r eta

i

n s s o

m

e u n

d

e s

i

r a

b l

e a n

d

o

b

j

e ct

i

o n a

b l

e _pr o_pe rt

i

e s

(

h

_{i g h} o r_ga n

i

c

m

at te r a nd odo r

)

a nd

i

s u s u a_{l l y} r e c_yc

l

ed thr o u_{g h} the s e c o nda r_y tr e atme nt

p

r o c e s s. T

h

e o nl y pr odu ct o f t

h

e d

i

ge ste r that r e

qu

i

r e s d

i

s

_p

o s al is the sta

b i

l

i

z ed s

l

u_{d g}e.

In 1 9 9 3,

U

S E P A la u n c

h

ed the n e e

d

fo r spe c

i

al d is

i

n fe ctio n of

b i

o s ol i ds s u ch a s

d i

_ge sted s ewa_ge slu

d

_ge

b

efo r e

it

c a n be

d

e_po s

i

ted o n a_gric u

l

tu r al la n

d

s o r ha v e othe r le s s

r e str

i

ct

i

v e

_{d i}

s_po s al o_pt

i

o n s

(

U

S

E P A 1

9

9

9

)

M

e s o_p

h i h

c d

i

_ge sted

b

io s o

l i d

s a r e cla s si fi ed a s

C

la s s _{B q}u al

it

_y a n

d h

a v e v e r_y r e stricte

d

u s e.

S l

u

d

ge

d

i ge stio n at the r

m

op h

i

l

i

c tem pe r atu r e s

o r

b

_y othe r adv a n c e

d

_pr o c e s s e s

i

s n e c e s s a r_y to

m

e et n ew sta nda rds fo r C la s s A B

i

o s ol i ds that

al low fo r

l

a nd a_{p p l}

i

c atio n a nd othe r le s s r e str ictiv e d

i

s_po s al o_ptio n s

T

h

e r

m

o_{p h i l}

i

c

d i

_ge st

i

o n c a n be c a r r

i

e

d

o ut e

it

h

e r a n a e r ob

i

c a

l l

_y, o r a e r o

b i

c a

l

l y. La r

g

e r

tr e at

m

e nt

f

a c

i

l

i

t

i

e s te n

d

to o_pe r ate a n a e r ob

i

c a

l l

_y

(

e _g

G

r e ate r V a n c o u v e r A n n a c

i

s Is

l

a n

d

W

a stew ate r Tr e at

m

e nt P la nt, 4

5

0

M

L / day f low

) (

Kr ugal et a

l

1 9 9 8; Z a

b

r a n sk a et al 2 0 0 3

)

S m

al le r o r

m

e

d

iu

m

siz e fa c

i l

it

i

e s te n

d

to o_pe r ate a e r o

b

ic a_{l l y}

₍

e.g British

C

olu

m b i

a '

s

W

h

i

stle r

W

a stew ate r Tr e at

m

e nt P

l

a nt, 1 2.5

M

L

/ d

a

y f low

₎

₍

Z ho u a nd

M

a v

i

n ic 2 0

0

3

₎

T he

a

d

v a nta_ge o

f

the a n a e r o

b i

c

d i g

e st

i

o n o

f

s

l

u

d

_ge

i

s _pr o

d

u ct

i

o n o

f

e n e r_{g y} a s

b i

o_ga s

(

Zabr a n s

k

a

et al. 2 0 0

3

)

. T

h

e

p

r o

d

u c e

d

e n e r

g

y c a n n ot o nl y s u

p

p l y the e n e rg y n e e

d

e

d

fo r t

h

e slud ge

tr e at

m

e nt

b

ut als o _pr o v

i

de a s u

b

sta ntial pa rt of t he e n e r_{g y} u s e

d b

_y the w

h

o le tr e at

m

e nt _{p l}a nt

T he t

h

e r

m

o_p

h i l i

c te

m

_pe r atu r e r a n_ge o

f

t

h

e a n a e r o

b i

c _pr o c e s s

b

r

i

n_gs a h

i

_g

h

e r e

f f i

c a c_y

i

n t

h

e

de_gr a

d

at

i

o n o

f

o r_ga nic

m

at te r a s s o ciate

d

w ith a h i g he r

b

io_ga s _pr o

d

u ct

i

o n a n

d

a lowe r c o nten t

o

f

v olat

i

le s o

l i d

s

i

n t

h

e

di

_ge ste

d

s

l

u

d g

e, w

h i

c

h

r epr e s e nts a

l

e s s e r a

m

o u nt o

f

o utput sta

b i l i

z e

d

slu_{d g}e w ith bet te r _{h y g}

i

e nic _qu al it_y

₍

Za

b

r a n ska et al. 2 0 0 3

)

.

T he o_pe r at

i

o n a

l

te

m

_pe r atu r e o

f

t

h

e r

m

o_p

h i l i

c a n a e r o

b i

c d

i

_ge st

i

o n

(

T

A D

₎

i

s u s u a

l l

_y

5 5 °

C I

m

_po rta n t r e a s o n s fo r a_{p p l y i}n _g the r

m

o_{p h}

i

l ic te

m

_pe r atu r e s a r e t

h

e bet te r s a n

i

t

i

z

i

n_g

ef fe ct o f the h i g he r _pr o c e s s te

m

_pe r a_tu r e a n d the ab i l

i

t_y to u s e lowe r r ete nt

i

o n t

i m

e s t

h

a n u s ed

fo r

m

e s o_{p h i h}c _{d i g}e st

i

o n _{B y} u_{p g}r ad

i

n

_g

e x istin _g

m

e s o_{p h}

i

l

i

c d

i

_ge ste r s to the the r

m

o_{p h}

i

l ic

te

m

_pe r atu r e r a n_ge, t

h

e

di

ge stin g c apa c

i

ty c a n be do u

b

led a nd c o n si

d

e r a

b

le r edu ctio n o f

patho

_g

e n c o nte nt c a n

b

e obtain e

d

(

Kr u_gal et al. 1 9 9 8 ; Zabr a n sk a et a

l

. 2 0 0 3

, Zabr a n ska et al

2 0

0

3

₎

Fo r _pr a ct

i

c al o_pe r at

i

o n o

f f

ul l-_{s c a}l_e

p la nts, a te

m

pe r atu r e

b

etwe e n 5 2 a nd 5

6

°

C i

s

pr efe r a

b

le, al low in g a sl i g ht v a r

i

at

i

o n

i

n the te

m

pe r atu r e w

i

tho ut fata

l

c o n s equ e n c e s fo r s o

m

e

of the a ctiv e

m i

c r o

b

e s

(

A hr

i

n_{g 1 9 9 4}

₎

. T he s e the r

m

op

h

i

l i

c te

m

pe r atu r e s k

i

l l

m

o st pat

h

oge n

i

c

ba cte r

i

a a nd

m

o st vir u s e s Howe v e r , s o

m

e he at

-_{r e s}

i

_{sta nt v}i_{r u s e s s u c}h _{a s t}h_e

pa r v o v ir u s w i l l

n ot be k i l led at a d i ge stio n te

m

_pe r atu r e of 5 5 °C

(

Lu n

d

et al 1 9 9 6 a n d B o r o v e c et al. 1 9 9 8

)

.

T he r e

f

o r e, in c r e a s e

d d

e

m

a n ds

f

o r pathoge n k i l l du r

i

ng a n a e r ob

i

c d i ge st

i

o n of slud ge c o u l d

in c r e a s e the inte r e st fo r d

i

_ge stio n at h

i

_{g h}e r te

m

_pe r atu r e s of 6 0

-6 5 "

C

to e n s u r e that t

h

e

m

ate r

i

a

l i

s _pr o_pe r

l

_y s a n

i

tiz e

d f

o r a

l

low

i

n_g u n r e str

i

cte

d

u s e a s a fe rt

i l i

z e r o n fa r

m

la n

d

(

A hr

i

n _g

2 0 0 1

₎

In a n e v alu at

i

o n o f a T A D at L

i

o n s

G

ate in _Va n c o u v e r, they s u c c e s sful l y tr a n sit

i

o n ed

fr o

m

a

m

e s o_{p h}

i

l

i

c to the r

m

o_{p h i h}c _pr o c e s s. T he

y fo u n

d

that a t

w

o

-sta_ge the r

m

o_{p h i l}

i

c

pr o c e s s, ope r at

i

n g at 5 5 "

c ol

i f

o r

m

(

F C

₎

r e_qu

i

r e

m

e nts w ith n o n

-dete ctab le

l

e v els of

S

a

l

mo n el la ba cte r

i

a. A

f

te r the fi r st

sta_ge,

m

e a s u r e

m

e nts a v e r age sl

i

g htl y a

b

o v e

C

a s s A le v els of F C of 1 0 0 0

M

P

N

/ g T S a n

d

afte r

the s e c o nd sta_ge, F C

m

e a s u r e

m

e nts a r e r el

i

ab l y below the fe c al c ol

i

fo r

m

up pe r l i

m

it fo r

C

la s s A r e_qu

i

r e

m

e nts. V olat

i

le s ol

i d

s

d

e str u ct

i

o n a n

d m

etha n e

ga s _pr odu ct

i

o n

w

e r e sl

i g

ht_{l y}

h i g he r tha n in the _pr e v

i

o u s

m

e s o_{p h i l}

i

c o_pe r at

i

n_g

m

ode, a n

d

ope r ato r s r epo rted that

the r

m

o_{p h}

i l i

c

b i

o s o l

i d

s a r e e a s

i

e r to

d

ewate r a n

d h

a n

d l

e. T he v

i

s u al ap pe a

l

of the

the r

m

o_{p h}

i

l

i

c b io s o l i

d

s a s a n a_gr

i

c u

l

tu r al a

m

e ndme nt

i

s als o

m

u c

h i m

_pr o v ed, ha v

i

ng a

l i

g ht

gr a n u la r te x tu r e

(

K

r u_gal et al 1 9 9 8

₎

.

T

h

e stab le a n

_d

ef fi cie nt o_pe r at

i

o n of the the r

m

o_{p h i l i}c a n a e r ob

i

c d

i

_ge ste r str o n _{g l y}

de_pe n

d

s o n t

h

e a c

fi

v

i

_{t y} o

f

a n a e r o

b i

c c o n s o rt

i

a

i

n t

h

e

_{d i}

_ge ste r

(

Za

b

r a n s

k

a et a

l

2 0 0 3

)

. T he r e

i

s a

l

a c

k

o

f

u n

d

e r sta n

d i

n_g o f the

d i f f

e r e n c e s

b

et

w

e e n

m i

c r o o r_ga n

i

s

m

s a ct

i

v e at the

t

h

e r

m

o_p

h i l i

c te

m p

e r atu r e s c o

m

_pa r e

d

to

m

e s o_{p h}

i l i

c te

m

_pe r atu r e s.

S

ewage slud

g

e o r ot

h

e r

t_{y p}e s of wa ste w i l l

m

a

i

nl y ho u s e

m

e s o_{p h i l}

i

c

m

ic r obe s

i

n clu d in_g a n a e r o

b

e s

₍

A hrin _g et a

l

.

2 0 0 2

₎

. H o

w

e v e r, t

h

e n u

m b

e r s o

f

t

h

e r

m

op h

i l

e s a n d e spe c

i

a

l l

y s o

m

e spe c

i fi

c gr o ups s u ch a s

a c etate-_ut

i

l i_zi_n

g

m

etha n o_ge n s, pr op io n ate -d_e

gr a

d

e r s o r c el lu

l

o s e-

d

e_gr ade r s w

i

l

l

ofte n

b

e v e r_y

low o r the s e _gr o u_ps c a n e v e n be

m i

s s

i

n_g

i

n the w a ste

₍

A

h

r

i

n_{g 1 9 9 4}

)

. T he o c c u r r e n c e o

f

the rm o_{p h}

i

le s

w i

l l

d

e_pe nd u_po n the

h i

sto r_y of the wa ste

m

ate r

i

al a nd the r efo r e s o

m

e

m

ate rial

w i

l l

s o

m

eti

m

e s ha v e u n_pr ed icta

b

_{l y h}

i

_{g h} n u

m

be r s of,

f

o r in sta n c e, the i t n op h i l ic

m

etha n oge n s

(

A

h

r

i

n

_g

2 0 0 2

)

.

C la s s A B io s ol i ds a nd L a nd A p p l ic at io n of Sewa

_g

e S lud ge

A s state

d

a

b

o v e, the r e

i

s c o n s

i d

e r a

b

le

m

ot

i

v at

i

o n fo r ap p l y

i

n

g

s

l

ud ge to la n

d

T

h

e

E P A

fi

r st _pr o

m

ul gate

d

c r

i

te ria fo r la n

d

a_{p p}

l

ic at

i

o n o

f

s ewa_ge s

l

u_{d g}e to c r o_{p l}a n

d i

n 1 9

7 9

, a n

d

c u r r e nt sta nda rds fo r the u s e a nd d

i

s_po s al of s ewa_ge slud ge w e r e in st

i

tuted

i

n 1 9 9 3

(

U S

E P A

1

99 9

₎

, w h

ic

h a r e c o

m m

o nl y r efe r r ed to a s the "

Pa rt 5 0 3

Sl

u d ge Rule. "

T h

i

s r ule _puts slu_{d g}e

in

to o n e o f two c ate_go r

i

e s : C

la s s

A a nd

C

la s s B .

C

la s s A slud ge

is s a

f

e

f

o r d

ir e c

t c o nta ct a n

d

c a n

b

e u s e

d

in a n u n r e str

ic

te

d m

a n n e r How e v e r,

C la s s

B slud ge

i

s o

f l

e s s e r qu a

l i

ty a n

d i

ts

u s e

i

s r e_gu late

d

w

i

t

h m

o r e st

ri

n_ge nt sta n

d

a r

d

s _pe rta

in

i

n_g to t he l

i m i

tat

i

o n s o

f d i

s_po s a

l

o_pt

io n s

a nd r e strictio n s o n a c c e s s o r c o nte nt. T he ge n e r al cri te ria fo r pathoge n s a nd fe c al c o l

if

o nn s

in

C l

a s s

A b i

o s o

h d

s a r e s u

m m

a r

i

z e

d i

n T a

b

le 1.

T ab le 1. Pat hoge n a nd Ind ic ato r C ri te r ia fo r C la s s

A

B io s ol i ds

Ite

m

Cr

i

te r

i

o n

V ia

b

le hel

m in

the s o v a < _{1 p}e r _{4 g d}r_y s ol

i

ds

Enteri c vir u s e s < 1 pe r 4 g dr_y s ol i ds

Sal

m

o n el la s_pe c

i

e s < 3 cfu _pe r 4 g dr_y s ol

id

s

Fe c al c ol i fo r

m

< 1,0 0 0 pe r g s ol i ds

B

e c a u s e slud ge

i

s a _pote ntial s o u r c e of n utr

ie n

ts a n

d

a _go o

d

s o

il

c o n

d i

tio n e r,

la n

d

a_{p p}

l i

c at

i

o n of s ew a_ge slu d ge

is a v e r

_{y p}r a ctic al a nd de s

ir a

b le

m

e a n s o

f

d

i

s_po s al Cu r r e n t_{l y}

abo ut 6 0

%

of the

m

u nic

i

_pal s e

w

a_ge slu_{d g}e in the U S is n ow la nd a_{p p l i}ed

₍

N

A S 2 0 0 2

₎

O

n e

i m

_po rta nt c o n si

d

e r atio n in the la nd a_{p p l}

ic a

t

i

o n of slud ge is the fa ct that slu _{d g}e c a n be

tr a n s_po rted e c o n o

m

ic al l y

m

u ch gr e ater d ista n c e s tha n w a ste

w

ate r Fo r e x a

m

_{p l}e.

N

ew Y o rk

C i

t_y '

s tr e ate

d

slu

d

_ge

i

s c u r r e nt

l

_y s

h i

_{p p}e

d

to n o rthe a ste r n T e x a s a n

d

e a ste r n

C

o

l

o r a

d

o

f

o r

c r o_p

la n

d a_{p p l}

ic a

t

io n

. An othe r c o n s

i d

e r at

i

o n

i

s that t

h

e u s e o

f

s ewage slud ge ha s be e n v e ry

s u c c e s sful in the r e sto r atio n o f st_{ri p}-

m

i_{n e}d l_{a n} d

. Estab l ish ing v egetatio n o n s u ch la nd is

e xtr e

m

e

l

_y

d i f f

i c ult du e to the la ck of n ut

ri

e nts, lo

w

o rga nic

m

at te r c o nte nt, low p H, low

w ate r r ete ntio n a n

d

to xic le v els of

m

etals

i

n the s o

i

l

₍

N

A

S

1 9 9 6

₎

Sew a_ge slu

d

_ge o v e r c o

m

e s