CE 111 — Environmental Engineering
Midterm Exam # 2 Answers (Fall 2003)
1. Dynamic Response of Reactor Systems
(a)
outlet
t
C
C*
0
0t*+V/Q
V/Q
(b)
outlet
t
C
C* exp(-kV/Q)
0
0t*+V/Q
V/Q
(c)
00t
outlet
C
C*/(1+kV/Q)
t*
τt*+τ
τ = 1+kV/Q
V/Q
2. On Water Quality Engineering
(a) Causes small particles to collide and adhere to one another, forming flocs. Flocs settle
more rapidly than individual particles.
(b) When only occasional/episodic treatment is required, PAC is favored over GAC.
(c) Scrape dirty sand off the surface and discard.
(d) Membrane filtration and sorption.
(e) Nonaqueous phase liquid. Liquid material such as oil that is immiscible in water.
3. Process Engineering for Water Treatment
(a) 32 µm
(b) 1.0 min
