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IV. Wastewater Treatment TechnologiesTopic. IV. 1. Wastewater Quality; General

Classification

Wastewater Quality Definition:

Wastewater is heterogenic mixture, containing impurities with various chemical composition, origin and dispersion, defining its quality.

Wastewater Quality Parameters Classification:

I. According to the Impurities Nature Physical Parameters

Dispersion Dry residuals Suspended solids Color Smell

Chemical Parameters Organic substances Non-organic substances Salts

Fats Proteins Carbohydrates Dissolved gases Ions

Biological Parameters Bacteria Viruses Protozoa

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Wastewater Quality; General Classification

II. According to the Impurities Dispersion

Dissolved - d < 10-6 mm Colloidal - d = 10-6 - 10-4 mm Suspended - d > 10-4 mm Fine - d = 10-4 - 10-2 mm Coarse - d > 10-2 mm

III. According to the Impurities

Chemical Content Organic Substances - 60 % Mineral substances - 40 %

IV. According to Biological

Impurities Nature Bacteria

Saprophytes Pathogens

Viruses

V. According to the Suspended Solids Settling Ability by 2 h

Norm - totally 65 g/d.ca Settling - 60 - 70 % Non-settling - 30 - 40 %

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Wastewater Quality; General Classification

Dissolved and Colloidal Substances

I. Mineral substances

Chlorides - 9 g/d.ca

Alkali substances

Sulphates (toxic if > 200 mg/l)

Phosphates Organic Mineral (orthophosphates)

Norm - 4,4 /d.ca

Nitrogen - 8 - 12 g/d.ca Organic (proteins, aminoacids) Mineral (

)

Heavy metals ions

Radioactive elements Measure - Kurie (Ku)

1 Ku = MRAD, which realises 3,7 / s

OHCOHCO

NHNaKMg

,,

,,,2

33

4

34

244243 ,, POHPOPOHPOH

34PO

3243 ,,, NONONHNH

OHNHOHNH 423

2223

2

,,,

,,,,

HgFeZnCr

PbCdMnNi

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Wastewater Quality; General Classification

Dissolved and Colloidal Substances

II. Organic substances

Fats - 10 %

Carbohydrates - 25 - 50 %

Proteins - 40 - 60 %

Carbamide

Detergents, Herbicides, Pesticides

22 )(NHCO