Page 165 - Membranes for Industrial Wastewater Recovery and Re-Use

lndustrial waters 139

Table 3.23 (continued)
Process/fibres Substances Organic (biodegradability)”
Inorganic
Dyeing
Cotton Na+Cr3+ C042-F- e-Naphthol (A); Acetate (B); Amides ofnaphtholic
Viscose Cu2+ N02-022- acid (B): Anionic dispersing agents (A): Anionic
Linen Sb3+ S2- Sz032- surfactants (A); Cationic fixing agents (NB): Chlor-
K+ so32- amines (SB): Formaldehyde (A); Formate (B): Nitro
NH4+ S042- amines (SB); Non-ionic surfactants: Residual dyes
(NB): Soaps (A); Soluble oils (SB): Sulphated oils (A):
Tannic acid (A); Tartrate (B); Urea (B)
Wool Na+ S042- Acetate (B): Dispersing agents (U); Formate (B):
K+ NH++ S032- Lactate (B); Residual dyes (NB); Sulphonated oils (A):
Cr3+ co32- Tartrate (B)
CU2+ CI-
~13+
Sb3+
Polyamide Na+ C03’- Acetate (B): Formate (B): Polyamide oligeines (U);
c1- Residual dyes (NB); Sulphonated oils (A)
Acrylic Na+ S042- Acetate (B); Aromatic amines (A): Formate (B);
cu2+ Levelling agents (U); Phenolic compounds (A):
NH4+ Residual dyes (NB); Retardants (U); Surfactants (A):
Thioreia dioxide (A)
Polyester Na+ S406’- Acetate (B); Anionic surfactants (A): Anti static
NH4+ c10- agents (NB); Dispersing agents (A): Dye carriers (SB);
NO3- EDTA (NB); Ethylene oxide condensates (U); Formate
c1- (B): Mineral oils (SB); Non-ionic surfactants (A):
SO,*- Residual dyes (NB): Soaps (A): Solvents (A)
Fireproofing
Cotton NH4+ P043- Chlorinated rubber (NB): Melamine resin (NB);
Wool Na+ B- Synthetic resin binders (U): Tetrabishydroxymethyl-
Sb3+ CI- : Br- phosphonium chloride (U); Thiorea resin (NB)
Ti2+ N03-:F-
Mothproofing
Wool Na+ F- Chlorinated compounds (NB); Formate (B):
K+: ~13+ Pentachlorphenol laurate (NB)
Waterproofing
Cotton Na+ CI- Acetate (B): Dispersing agents (U); Fluoroacrylic
Linen K+ esters
Wool ~13+ (U): Formate (B): Gelatine (B): Melamine resins (NB):
Paraffin wax (NB); Silicone resins (NB):
Stearamidemethyl pyridinium chloride (NB): Stearate
(B): Titanates (NB)

a B, biodegradable: A, biodegradable after acclimatisation: U, unknown; NB, non-biodegradable: SB,
slowly degradable.
chelating agents are generally used during bleaching or in the final rinses,
contributing to the pollution load (Cooper, 1978: Nolan, 1972). Bleaching
wastewater usually has a high solids content with low to moderate BOD levels
(Table 3.21). The dissolved oxygen content of these effluents may be raised by
the decomposition of hydrogen peroxide (Porter, 1990), but residual hydrogen