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Flashcards in chap 13 Deck (32):
1

SP. 1a. List 4 boards categories of methods used to separate DO from water

adsorption
exclusion
stripping
extraction

2

SP. 1b. What types of contaminants are removed using these techniques?

dissolved organics

3

SP.1b. ii. Distinguish between the phases and surfaces used in each of these techniques

-adsorption: liquid/solid partition
-exclusion: liquid/liquid
-stripping: liquid/gas
-extration: liquid/liquid

4

SP.1c which of the tech described for removing DO from water are suitable for

-non-polar molecules - Adsorption
-slightly polar organic molecules - exclusion
-large organic molecules -
-volatile organic compounds - stripping

5

SP.1c which of the tech described for removing DO from water are suitable for

-non-polar molecules - Adsorption
-slightly polar organic molecules - exclusion
-large organic molecules -
-volatile organic compounds - stripping

6

SP.1d. distinguish between the operating principles behind RO, membrane separation and pervaporation

-RO:
-membrane:
-pervaporation: permeation + evaporation

7

SP.1e. how are the waste streams dealt with in
GAC
Pervaporation
Stripping

GAC- once GAC is spent, it is burnt and the exhaust must be scrubbed of HCl, backwashing
Pervaporation:
stripping: Contaminants are partitioned into the air (or steam stream) therefore will be removed by GAC or Catalyst combustion using propane as a fuel

8

SP.1f . why would you have to protect an RO from BTX (Benzene, Toluene, Xylene)

BTX dissolves the membrane
GAC would be installed upstream of an RO unit to protect the RO membrane which can be oil soluble.

9

SP2a. List 3 board categories of tech used to destroy the organics in water

Chemical Oxidation
Biological Oxidation -
bio reduction - H2

10

SP2c. list the oxidants commonly used to destroy DO chemically

air, chromic acid, ozone, hydrogen peroxide, supper oxidation,
chlorine, ClO2

11

SP2c. list the oxidants commonly used to destroy DO chemically

air, chromic acid, ozone, hydrogen peroxide, supper oxidation,
chlorine, ClO2

12

SP2d. Chemicals sent to Swan Hills to be destroyed, what types of oxidation tech is used, what has to be done to the waste stream if heteroatoms are in the waste

Heteroatoms are atom that found in cyclical O compounds, does not include H,C. contains P,S,N,O, As
Bioreduction - reduced species such as h2S

13

SP2e. Advantages an disadvantages of Ozone and chlorine and recommend sutable application for each

Ozone:
ADV: low capex, source from air
DIS: high opex cuz use a lot of Electricity, toxic, strong oxidation, hard to handle, can not leave residual in water
Chlorine:
Application: disinfect water prior chlorination
ADV: leaves residual in water,easy to use, low capex
DIS: products are chlorinated substances
Application: kill bacteria and virus

14

SP2f. sometimes Ozone is used to remove DO from water and sometimes hydrogen peroxide is used. compare ADV, DIS of each method. Application

Hydrogen Peroxide:
ADV: not toxic as Ozone
DIS: reaction slow
Application: Toxicity reduction, BOD/COD removal

15

SP2g. O, OH, HOCl are oxidants used to eliminate dissolved organics from water. Give some of the chemicals used to supply these compounds

Ozone (O.)
Hydrogen peroxide (OH)
Chlorine - HOCl

16

SP2h. when BOIX is used to remove dissolved organics from water, do the microorganisms what supply the energy (delta G) for the reactions

supply: air (oxygen), water, carbon (food for the organisms)
the microorganism are required for the process: mircoorganism fed on the dissolved organic waste producing carbon dioxide and ater.
SOC: Synthetic organic carbon can not be dissolved by microorganism

17

SP2i. List the requirements for the long term maintenance of the ecosystem required in BIOX and how they are supplied

Food/BOD: maintain control w efficient BOD removal, the proper amt of food must be supplied
DO: Insufficient oxygen level inhibit BOD removal
pH/toxicants: rapid change in pH or type of waste organic inhibit the process
Time; the degree of degradation varies with time
Nutrients: bac required to trace amt of N, P for cell maintenance
Temperature: low temp -> slow rate
high temps -> kill many strain of bac

18

Adv and Dis of CHEMOX & BIOX

BIOX:
ADV: not dangerous like CHEMOX
DIS: reaction slow than CHEMOX (compare BOD5 and COD analyses
Different rate of bio-degradadion on # compounds

19

SP2k. Define F/M ratio and then give the configurations which are suitable for streams with high F/M ratio and for low F/M ratio

Food/ Microorganism ratio
High F/M:
-activated sludge oxidation
Low F/M
-aeration basin and oxidation ditches (12-48)

20

SP2l. which BIOX applications are suitable for a large foot print and which are suitable for a small foot print

-large foot print

21

SP3a four ways to remove oil and grease from water

1. separation
2. coalescense
3.filtration
4.chemical treatment

22

SP3b. two factors from the stokes equation are most significant for the removal of OG

size and density

23

SP3c. some examples of where sheering forces on OG drops in water

Sheering energy break OG to small drops
when the mixture goes thru the pumps
affects on settling time require to remove OG from water: long time

24

SP3d. baffles are sometimes added to skim tanks to improve separation of OG from water. what are the baffles added for, why is it that sometimes these baffles reduce separation efficiency

baffles are added -> shearing energy added to make the water droplets smaller and take more time to be separated
if designed is wrong, baffles can reduce separation efficiency
no baffles: water moves in narrow stream thru the tank

25

SP3d. baffles are sometimes added to skim tanks to improve separation of OG from water. what are the baffles added for, why is it that sometimes these baffles reduce separation efficiency

baffles are added -> shearing energy added to make the water droplets smaller and take more time to be separated
if designed is wrong, baffles can reduce separation efficiency
no baffles: water moves in narrow stream thru the tank

26

SP3E. folded API separators are fully designed to improve the separation of oil from water by optimizing two factors

Settling ponds with skimming on the top and water remove below
increasing Vt from increasing different in density by adding diluents (lighter fractions) to the oil

27

SP3f. Term sorbant. explain how sorbants are used to increas

sorbant: polypropylene in the form of string or fabric in order to make large suface

28

how sorbant are used to increase the size of droplets

adhesion: attraction bwt liquid and solid surface and wet the surface

29

how the waste stream each type of sorbants are managed

silica sand : backwash
Polypropylene: adhesion great that oil stick irresversibly nutshell coalescing filter
coalescence: thin film on the surface with formed by adhesion wetting the surface

30

SP3g. distinguish bwt IGF and DAF

Static Induced gas flotation units: bubble of oil stick to bubble of gas
dissolved air flotation: high pressure gas release

31

Emulsion form when surfactants are added to mixtures of OG and water

smaller drops higher surface tension the less stable emulsion become
surfactants: non polar end dissolves in oil and polar end dissolves in water/ reduce the surface tension /give the surfae of the drop a charge

32

some sources of surfactant in waste stream

municipal waste:
soaps and detergents
oil production facilities
acid: low pH =drops become charged
corrosion inhibitor: wetting to stable the oil drops
scale inhibitor: