L2- Water Characteristics

Question 1

Physical water characteristics

Answer 1

Turbidity, temperature, colour, odour

Question 2

Total Solids (TS) comprises of what, and is formed when?

Answer 2

Total suspended solids (TSS) or Total dissolved solids (TDS):
Volatile suspended solids (VSS) and fixed suspended solids (FSS) or VDS and FDS

Total volatile solids (TVS) = VSS + VDS
Total Fixed solids (TFS) = FSS + FDS

Formed at evaporation at 105deg

Question 3

Temperature effects

Answer 3

O2 solubility (lower in warm conditions)
Biochemical & chemical kinetics
m/o growth rate (higher in warm)

Question 4

How odour comes about in water and wastewater?

Answer 4

Water- high concentration of substance (usually Cl2)

Wastewater- organic degradation (septic/anaerobic wastes), i.e. H2S, NH3, S

Question 5

Colour for aerobic and anaerobic (septic) conditions

Answer 5

Aerobic- brown-yellow (fresh)

Anaerobic- black; iron sulfide (FeS) from anaerobic degradation

Question 6

Organic compound examples

Answer 6

Proteins, HC, lipids, urea, surfactant, VOCs

Question 7

Nitrogen types and its impacts

Answer 7

Inorganic (ammonium) & organic (urea, proteins)

Impact: O2 consumption (nitrification);
NH3 is toxic to fish;
N (+P) -> Eutrophication

Question 8

Phosphorus types and impact

Answer 8

Inorganic (mainly) & organic

Impact: Eutrophication with N
H2S -> odour
H2SO4 -> corrosion

Question 9

Heavy metal examples and impact

Answer 9

Cu, Pb, Zn, Ni, Fe, Hg

Toxic in high quantities -> plumb solvency issues

Question 10

Eutrophication

Answer 10

Explosive algae growth, which depletes water of oxygen when algae die -> toxic and foul smelling

Question 11

Gases produced during degradation of organics

Answer 11

CO2, CH4, NH3, O2, H2S

Question 12

Effect of alkalinity

Answer 12

Content of salts affect growth of m/o

Question 13

Chemical Oxygen Demand (COD)

Answer 13

Oxygen consumptions as a result of chemical oxidation of organics (indirect measure of organics in water)

Question 14

Biochemical oxygen demand (BOD)

Answer 14

Amount of dissolved oxygen needed by aerobic biological organisms in the body of water to break down organic material present in given sample

Question 15

Total organic carbon (TOC)

Answer 15

amount of carbon bound in organic compounds

Question 16

Dissolved oxygen (DO)

Answer 16

Measure of the amount of oxygen dissolved/carried in a given medium

Question 17

BOD/COD criteria

Answer 17

BOD/COD<0.6 = non-biodegradable

(BOD/COD>0.6 = biodegradable, where 0<BOD/COD<1)

Question 18

Conventional pollutant classifications

Answer 18

Typical municpal sewage (BOD, TSS, fecal coliform bacteria,oil & grease, pH)

Question 19

Non-conventional pollutant classifications

Answer 19

pollutants not in conventional & toxic (COD, TOC, N,P)

Question 20

Priority pollutant classification

Answer 20

pollutants cause death, disease etc., after discharge, exposure & ingestion

Question 21

Conservative pollutant classification

Answer 21

pollutants not normally physically/chemically transformed to non-toxic substances (salts & metals)

Question 22

Non-conservative pollutant classification

Answer 22

pollutants normally transformed to non-toxic substances (BOD, NH3, some organics)

Question 23

Categories of Wastewater and water

Answer 23

WW: industrial (textile, plastics), agro-industrial (food), clinical (hospital), nuclear

Water: grey, yellow, black from municipal