Figure by MIT OCW.

Adapted from: Rittman, Bruce E., and Perry L. McCarty. Environmental Biotechnology: Principals and

Applications. New York, NY: McGraw-Hill, 2001.

200 40 60 80 100

0.25

0.50

0.75

1.0

S f/ S

s

Atta

chm

ent S

urfa

ce

Case a

Case b

z, µm

Case a: τ1 = 11 µm, Lf /τ1 = 9.1Case b: τ1 = 450 µm, Lf /τ1 = 0.22

Bulk Liquid

Substrate concentration profiles for characteristic deep (case a) and nearly fully penetrated (case b) biofilms. The ratio Lf /τ determines if the biofilm is deep. Many values of k1, Df , and Xf can give the same τ1 value, and Rittman and McCarty (2001) illustrate how this affects J1.

Figure by MIT OCW.

Con

cent

ratio

n

Attaching Surface

Biofilm

z

Fully penetrated

Diffusion Layer

Bulk Liquid

Sb

Sw

Ss

Distance normal to the surface of the biofilm

Characteristic Substrate Concentration Profiles within a Biofilm

L

Shallow

Deep

Lf

Adapted from: Suidan, M. T., B. E. Rittman, and U. K. Traegner. "Criteria establishing biofilm-kinetic types." Water Research 21, no. 4 (April 1987): 491-498.

-6-3 -2

Typical response of a steady-state biofilm to changes in S. For this example, Smin = 0.0204 mg/cm3. S has units mg/cm3, and J has units mg/cm2-d.

-1

Deep

Sdeep

Smin = K b'Yq - b'

1st Order

Approaching 1/2 - order

Steady-state solution

0 +1

-5

-4

-3

-2

-1

0

log 1

0J

log10S

Figure by MIT OCW.

Adapted from: Rittman, B. E., and P. L. McCarty. Environmental Biotechnology: Principles and Applications. Boston, MA: McGraw-Hill Higher Education, 2001.

Source: U.S. EPA, 2000. Wastewater Technology Fact Sheet: Trickling Filters. Report No. EPA 832-F-00-014. Office of Water, U.S.

Environmental Protection Agency, Washington, D.C. September 2000.

Trickling

filter

B

B

AA

Floor slope

Underdrain

blocks

Effluent Channel

Underdrain

block

SECTION A-A SECTION B-B

UNDERDRAIN BLOCK FLOOR PLAN

Top of Bed Top of Bed

Depth of Media or Packing Depth of Media or Packing

Slab

AA

AC AD

AB

TRICKLING FILTER DETAILS

Effluent Channel

Figure by MIT OCW.

Adapted from: Reynolds, T. D., and P. A. Richards. Unit Operations and Processes in Environmental

Engineering. 2nd ed. Boston, MA: PWS Publishing Company,1996, p. 543.

Figure by MIT OCW.

Adapted from Gonzalez, J. F. Wastewater Treatment in the Fishing Industry.

Sludge to treatment or disposal

Primary settlingSecondary settling

Raw wastewater

Treatedwastewater