Download presentation
Presentation is loading. Please wait.
1
Dr. Martin T. Auer MTU Department of Civil & Environmental Engineering Mass Balance, Kinetics & Reactors
2
Environmental Response …the question is not will a system will respond, but rather when and to what extent. (Cooke et al. 1999) and, as engineers, we might add ‘ at what cost ’ ?
3
Lake and River Management …the environmental engineering equivalent of building a bridge to nowhere. (Thomann and Mueller 1987, p. ix) http://www.zen39641.zen.co.uk/ps/
4
Drinking Water Treatment …the environmental engineering equivalent of building a bridge that falls down. (Thomann and Mueller 1987, p. ix) http://www.jansenkiener.com/Bridge%20Engineering.htm
5
Plug Flow Reactor Completely-Mixed Flow Reactor Reactor Analogs
6
CMF Reactor
7
Control Volume
8
Zero Order Kinetics Oxygen in Dollar Bay Zero Order k = 0.13 mg∙L -1 ∙d -1 C t = -k∙t + C 0
9
First Order Kinetics Radioisotope Decay k = 0.036 yr -1 t 0.5 = 19.25 yr lnC t = -k∙t + lnC 0
10
Temperature and Kinetics Theta Function
11
Temperature and Kinetics WWTP Nitrification Effluent Ammonia Load (MT∙d -1 ) J F M A M J J A S O N D
12
CMF Reactor with first order decay time-variable or steady state application
13
For many years, Allied Chemical and its ancestors produced soda ash … a chemical used to soften water and in the manufacture of glass, soap, and paper. The raw materials were two locally abundant minerals: CaCONaClNaCOCaCl 3232 and the products were soda ash (Na2CO3) and calcium chloride (CaCl2) waste. The wastes were deposited in 2000 acres of lagoons along the banks of 9 Mile Creek. The waste continually leaks from the lagoons into the creek, making the water highly ‘salty’. Chloride in 9 Mile Creek
15
Response Time assume no input, divide by V, collect terms and integrate, assume SS when 95% completed, i.e.
16
Response Time Wastewater Treatment Grit removal, 0.5 hr 1°, 2° settling, 1-2 hr Activated sludge, 4-8 hr Anaerobic digestion, 15-30 d Drinking Water Treatment Rapid mix, <1 min Flocculator, 30 min Disinfection, 15 min Natural Systems Onondaga Lake (0.25 yr) Lake Ontario (8 yr) Lake Michigan (136 yr) Lake Superior (179 yr) Typical ‘fast’ k, 30 yr -1 Typical ‘slow’ k, 0.03 yr -1
17
CCe tss kt F H G I K J 1 1 CCeCe t kt kt F H G I K J F H G I K J F H G I K J 1 1 2 1 1 CCe t kt F H G I K J F H G I K J 2 1 1 Time-Variable Response
18
SS CMF Application to Lakes where W = Q∙Cin, i.e. the loading
19
SS CMF Application to Lakes
20
Batch Reactor in Pipe
32
Train of Batch Reactors
33
PF-CMF Comparison: Reactor Efficiency
34
PF-CMF Comparison: Sensitivity to Spikes
35
PF Reactor – Application to Rivers
36
Example 4.14 PCBs in Lake Superior Dr. Perlinger’s research group sampling on Lake Superior aboard the U.S. EPA research vessel Lake Guardian.
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.