INTRODUCTION TO ENVIRONMENTAL ENGINEERING

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INTRODUCTION TO ENVIRONMENTAL ENGINEERING
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Chapter 1 - Introduction

• 1-1 What is Environmental Engineering?
• (NIB) American Academy of Environmental
  Engineers
• 1-3 Environmental Systems Overview
• Systems as Such water, air, solid waste
• Water Resource Management System
• Figure 1-2
• water supply sources, types of treatment

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Chapter 1 (continued)

• Figure 1-3
• wastewater sources
• sewer system types
• (NIB) diurnal dry weather flow
• wet weather flow sources (II)
• POTW, WWTP
• (NIB) IWPCA Hall of Fame

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Chapter 1 (continued)
1-4 Environmental Legislation and
Regulation Water Quality Management Drinking
Water (Safe Drinking Water Act, 1996) Water
Pollution Control (Clean Water Act, 1977) NPDES
Permits Environmental Legislation and Regulation
in the 1980s (NIB not significant event)
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Chapter 1 (continued)
1-5 Environmental Ethics Case 2 Noise
Control (NIB) Clayton, IN WWTP noise
problem 1-6 A Materials Balance Approach to
Problem Solving Example 1-3 Mass Balance (NIB)
Flow measurement method
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Quiz 1
Question 1-5 Homeowners in the town of Rolla,
MO, have connected their downspouts and the sump
pump from their footing drains to the sanitary
sewer system. The rainwater and sump water
entering the sewer is called (choose one) (a)
Infiltration (b) Inflow These connections to the
sanitary sewer, in effect, make it a (choose
one) (a) Storm sewer (b) Combined sewer
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Quiz 1
Question 1-5 Homeowners in the town of Rolla,
MO, have connected their downspouts and the sump
pump from their footing drains to the sanitary
sewer system. The rainwater and sump water
entering the sewer is called (choose one) (b)
Inflow These connections to the sanitary sewer,
in effect, make it a (choose one) (b) Combined
sewer
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Chapter 2 - HYDROLOGY

• 2-5 Groundwater and Wells
• Figure 2-22
• pump unit types above ground motor, submersible
  motor
• well casing
• well screen
• flood protection
• Figure 2-24
• Static Water Table
• Drawdown

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Chapter 3 - Water Treatment

• 3-1 Introduction
• Potable water versus palatable water
• Substances in water
• suspended solids
• colloidal
• dissolved

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Chapter 3 - Water Treatment (continued)

• Physical Characteristics (p. 155)
• Nephlometric Turbidity Unit (NTU)
• Color
• Taste and Odor
• Chemical Characteristics
• Iron
• Manganese
• Microbiological Characteristics
• E. coli

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Chapter 3 - Water Treatment (continued)
Water Quality Standards Safe Drinking Water
Act Lead and copper Disinfectants and
disinfectant by-products HAA5 haloacetic
acids TTHMs total trihalomethanes
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Chapter 3 - Water Treatment (continued)
Surface Water Treatment Rule Turbidity of 0.5
NTU 99.9 (3-log removal) of Giardia Total
coliforms essentially zero
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Chapter 3 - Water Treatment (continued)
Water Sources surface and groundwater Figure
3-6 Conventional surface water treatment
plant pump/screen rapid mix flocculation
basin sedimentation basin rapid sand
filter disinfection storage (NIB) high service
pumps
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Chapter 3 - Water Treatment (continued)

• (NIB) Conventional groundwater treatment plant
• wells (to WTP or directly to distribution with
  disinfection)
• oxidation of iron (by aeration or chlorine)
• ferrous to ferric
• pressure or gravity filters
• backwash holding tank, sludge lagoon
• clearwell
• high service pumps

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Chapter 3 - Water Treatment (continued)
Coagulants Alum and Ferric Chloride Figure
3-10 Jar Tests Hardness, expressed as calcium
carbonate treatment Lime - Soda
softening Ion-Exchange softening resins,
Zeolite
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Quiz 2
1. Question 2-5 (modified, extra credit) When a
flood has a recurrence interval (return period)
of 5 years, it means that a chance of another
flood of the same or greater intensity occurring
next year is (X) percent. X ? 2. The
difference between the static water level in the
well casing when the pump is off and the water
level in the well casing when the pump is on is
call the _________ .
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Quiz 2
1. Question 2-5 (modified, extra credit) When a
flood has a recurrence interval (return period)
of 5 years, it means that a chance of another
flood of the same or greater intensity occurring
next year is 20 percent. 2. The difference
between the static water level in the well
casing when the pump is off and the water level
in the well casing when the pump is on is call
the drawdown .
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Chapter 3 - Water Treatment (continued)
3-4 Reactors Types batch reactor (fill and
draw) completely mixed flow reactor plug-flow
reactor Theoretical detention time, t0 Real
detention time lt t0 short circuiting dead
spots density currents
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Chapter 3 - Water Treatment (continued)
3-5 Mixing and Flocculation Figure 3-26, p.
205 Rapid Mix Basin t0 lt 30 seconds (NIB,
10-States Standards) Flocculation Basin t0 gt 30
minutes (NIB, 10-States Standards)
flow-through velocity gt 0.5 feet per
second lt 1.5 feet per second
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Chapter 3 - Water Treatment (continued)
3-6 Sedimentation Figure 3-29 Rectangular and
circular sedimentation tanks
(clarifiers), p. 212 inlet zone settling
zone sludge zone effluent weir t0 gt 4 hours (NIB,
10-States Standards)
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Chapter 3 - Water Treatment (continued)
Sedimentation Concepts Figure 3-32, p.
216 Settling velocity, vs Overflow rate, vo
(liquid velocity) vo Q/As depth/time
vo lt vs
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Chapter 3 - Water Treatment (continued)
Example Design nine clarifiers for flow of 3
m3/sec, surface overflow rate of 1.2 m/hour, and
detention time of 4 hours. Q 3 m3/sec vo
1.2 m/hour to 4 hours Surface area of tanks,
As Q/ vo (3 m3 )(hour)(60 sec)(60 min)

(1.2 m)(sec)(min)(hour) 9,000
m2 surface area per tank 1,000 m2
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Chapter 3 - Water Treatment (continued)
Example Design clarifier for flow of 3 m3/sec,
surface overflow rate of 1.5 m/hour, and
detention time of 4 hours. Volume of tanks, V
(Q)( to) (3 m3 )(4 hours)(60 sec)(60 min)

(sec)(min)(hour) 43,200 m3 Volume per tank
43,200/9 4,800 m3 Tank depth, D V/As
43,200 m3 / 9,000 m2 4.8 m
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Chapter 3 - Water Treatment (continued)
3-7 Filtration Figure 3-41 Rapid Sand Filter, p.
232 filter media filter surface area,
As backwash (washwater) loading rate, va
Q/As
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Chapter 3 - Water Treatment (continued)

Example Design the rapid sand filters for a
water treatment plant with a design flow of 3
m3/sec with maximum surface loading rate of 4.8
m/hr and four filter boxes Minimum filter
surface area, As Q/ va (3 m3)(hour)(60
min)(60 sec)
(4.8 m)(sec)(hour)(min)
2250
m2 Assume only three filters in service Surface
area per filter 2250/3 750 m2
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Quiz 3
Question 3-7 In the U.S. chlorine is preferred
as a disinfectant over ozone because it has a
residual. Why is the presence of a
residual important? The presence of a residual
is important because it provides some protection
in case of contamination of the water
distribution system. Explain how contamination
can occur.
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Quiz 3
Question 3-7 Answer When fighting a fire, the
fire truck pumper connected the fire hydrant can
cause the pressure in the water main to go
negative, sucking contamination into the water
main through leaks in the pipe or plumbing
cross-connections.
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Chapter 3 - Water Treatment (continued)
3-8 Disinfection Chlorine gas Sodium
Hypochlorite (bleach) CT concept Chloramines Chl
orine Dioxide Ozone Ultraviolet Light (UV)
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Chapter 3 - Water Treatment (continued)
3-9 Adsorption Granular Activated Carbon
(GAC) Powdered Activated Carbon (PAC)
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Chapter 3 - Water Treatment (continued)
3-10 Water Plant Waste Management Sedimentation
basin sludge production Example 3-29, page
253 dry solids versus wet solids Dewatering
lagoon, sand-drying beds mechanical
centrifuge, plate and frame press,
belt filter press
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Chapter 3 - Water Treatment (continued)
3-10 Water Plant Waste Management Ultimate
Disposal (of dewatered sludge cake) 1.
Co-disposal with sewage sludge 2. Landfilling 3.
Land spreading (NIB) Disposal of thickened
sludges Bedford WTP North Vernon WTP
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Quiz 4
Terre Haute Water Treatment Plant 1. What are
the two types of wells at the plant. 2. Where
is the aerator located in the treatment process
and what treatment function does it
perform? 3. Where is the aerator commonly found
at other water treatment plants and what
treatment function does the the aerator
perform at these plants?
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Quiz 4
Terre Haute Water Treatment Plant 1. Vertical
well and horizontal collector well. 2.
Following filtration and is intended to air strip
volatile organic compounds. 3. Before
filtration to oxidize iron.
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Review for Test 1
Definitions American Academy of Environmental
Engineers IWPCA 10-States Standards combined
sewer, infiltration, inflow, diurnal POTW, WWTP,
NPDES TTHMs, HAA5, CT, NTU
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Review for Test 1
Definitions hardness expressed as real
detention time forms of chlorine for
disinfection other means of disinfection cross-con
nections, air break tank, backflow preventer GAC,
PAC
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Review for Test 1
Draw a treatment process diagram for a typical
groundwater treatment plant for iron removal and
label each process, including sludge handling and
disposal. Also show the two different methods
for iron oxidation. Draw a process diagram for a
typical surface water treatment plant and label
each process, including sludge handling
and disposal. Tracer concentration problem
(1-5) Biodegradation reaction rate constant
problem (1-11)
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Review for Test 1
Detention times for rapid mix, flocculation and
sedimentation tanks per 10-States
Standards Calculate the volume and dimensions of
sedimentation basins and filters given loading
rates and treatment flow rate and detention
time. (3-70, 3-75, 3-76) Sludge production
problem (Example 3-29, page 253)