Wastewater Treatment Personnel Book

Front 1

A water seal on a pump serves a dual purpose, it acts as a lubricant and keep gritty material from entering the _________ ____.

Back 1

Packing Box

Front 2

In a centrifugal pump, internal leakage is prevented by:

Back 2

Wear Rings

Front 3

An ________ is the line leaving the plant.

Back 3

Outfall

Front 4

Cattails in a lagoon will cause____ _______ in the lagoon.

Back 4

Short Circuiting

Front 5

High ___ ___ is not a cause of short circuiting in a pond.

Back 5

influent BOD

Front 6

Why are check valves used in conjunction with centrifugal pumps?

Back 6

To prevent wastewater in the suction line from flowing back into the wet well.

Front 7

Wear rings are installed in a pump to concentrate wear on a:

Back 7

economical replaceable part

Front 8

If a centrifugal pump loses its prime after starting, ___ leaks into the pump through the stuffing boxes.

Back 8

air

Front 9

The best way to tell when enough sludge is been withdrawn from the primary tank is:

Back 9

Note the consistency of the sludge by sampling from the pump discharge line.

Front 10

Settled activated sludge is _____ than raw sludge.

Back 10

thinner

Front 11

Control of sludge wasting rate by constant MLVSS concentration involves maintaining a certain concentration of:

Back 11

Volatile suspended solids in the aeration tank.

Front 12

Under ice and snow cover, the BOD level in ponds will normally:

Back 12

increase slowly

Front 13

Air ____ controls the rotation of RBC.

Back 13

volume

Front 14

Lines free on ice are normal conditions for a _______ control gas chlorination system.

Back 14

manual

Front 15

When a high organic waste load reaches an activated sludge plant, the operators first indicator is a decrease in:

Back 15

D.O. residual

Front 16

Disaster planning is useful in reducing _______ in the event of a disaster.

Back 16

confusion

Front 17

A major characteristic if a metal plating waste is high is:

Back 17

toxicity

Front 18

A wet well probe is usually used for ________ determinations of level.

Back 18

Single-point

Front 19

In electrical circuits a _______ is used to reduce the voltage where necessary.

Back 19

transformer

Front 20

When a fire hydrant is operated, it should be opened ______.

Back 20

fully

Front 21

A 42 inch pipe is flowing at a rate of 6.5 ft/sec. What is the flow in cu/ft sec? Formula on back of card.

Back 21

42 ÷ 12 = 3.5, .785 x 3.5 x 3.5 x 6.5 = 62.5 cuft/ sec

Hint 21

After ft conversion, All multiplication

Front 22

If packing is not maintained properly, loss of _____ will occur due to _____ being allowed to enter pump.

Back 22

suction, air

Front 23

Air flow through a trickling filter when the influent is warmer than the air temperature is _______ through the filter.

Back 23

upward

Front 24

What is affected when the aerobic digestion process is starting to deteriorate?

Back 24

Volatile Acid:Alkalinity Ratio

Front 25

A malfunctioning gas chlorination system has normal gas pressure, no feed rate indicated on rotameter, and no injection vacuum. What is the most likely cause of the problem?

Back 25

Injector clogged

Front 26

The most critical criteria for determining when a mixed media filter should be backwashed is _______ effluent quality.

Back 26

filter

Front 27

The precipitate in coagulation with alum is aluminum ________.

Back 27

Hydroxide

Front 28

The correct amount of chemical used to remove turbidity is known as the ________ dosage.

Back 28

optimum

Front 29

The temperature of a anaerobic digester should be changed as slowly as possible to allow _______ time to adjust.

Back 29

bacteria

Front 30

The 2 factors that indicate that a filter press cycle is complete are small ______ discharge and nearly constant pump _______.

Back 30

filtrate, pressure

Front 31

The quality of volatile solids in the content of the incoming sludge is an indirect measure of ______ available for bacteria in the digester.

Back 31

food

Front 32

What 4 organisms will be found in a balanced, good settling mixed liquor?

Back 32

Free swimming and stalked ciliates, some flagellates, and rotifiers

Front 33

Belt filter presses are operated as a __________ process.

Back 33

continuous

Front 34

Formula: Lbs MLSS under aeration

Back 34

Inf flow (mgd) x prim eff (mg/l) x 8.34 x ( sludge age days ) = lb mlss ------basically lbs/day x sludge age

Front 35

Math Data: 2.5 ft wide channel, flow depth is 1.4 ft, flow rate is 7.2 mgd. Need average velocity?

Back 35

Flow (gpd) ÷ Area x conversion factors =7,200,000 ÷ (2.5 × 1.4) × 7.48 × 86400 sec/day= 3.2 ft/sec. (60 × 1440= 86400)

Hint 35

Q/A. 72,000,000÷ 2.5 x 1.4 x 7.48x 86400 sec/ day= 3.2 ft/sec

Front 36

A 240 gpm mixed media filter operated at a rate of 2 gpm/sq ft is backwashed at a rate of 15 gpm/sq ft. How many gallons of wash water were used?

Back 36

Gal wash water= backwash rate x filtration flow through ÷ filtration rate.....15 gpm/sq ft x 3 min x 240 gpm ÷ 2 gpm/sq ft= 5400 gal

Front 37

How to calculate percent volatile solids?

Back 37

volatile solids ÷ total solids

Front 38

Treatment Basins (such as primary sedimentation, grit tank, aeration tank, and final clarifier) drains must be ________ than the receiving sump to allow for gravity flow out of the basin.

Back 38

higher

Front 39

When a great deal of authority is delegated on many levels, an organization may be described as:

Back 39

Decentralized

Front 40

Delegating power for decisions to lower levels is considered ______.

Back 40

Decentralized