Induesturies part 2

TEXTILE INDUSTRY

TEXTILE INDUSTRY

INTRODUCTION The textile dyeing and finishing sector uses

large volumes of water and substantial quantities of complex chemicals.

Significant challenges associated with the acquisition and disposal of the raw materials.

The charges incurred for mains water supply and effluent disposal are increasing, and companies need to address these issues to save money and remain competitive.

For cotton textile industry

FOR WOOLEN TEXTILE INDUSTRY

POLLUTION PROBLEMS IN TEXTILE INDUSTRY

Color Dissolved solids Toxic metals Residual chlorine Others (like non-biodegradable

organics)

TEXTILE INDUSTRY WASTE WATER CHARACTERISTICS

TREATMENT OF WASTE WATER

Oxidation techniques: the treatment of synthetic dye house effluent by ozonization, and hydrogen peroxide in combination with Ultraviolet light; Sodium hypochlorite decolorizes dye

Electrolytic precipitation & Foam fractionation: reduction in the cathode space of an electrolytic bath; surface-active solutes collect at gas-liquid interfaces

Photo catalytic degradation: photoactive catalyst illuminates with UV light, generates highly reactive radical, which can decompose organic compounds.

Thermal evaporation: Use of sodium per sulphate; oxidative decolourisation of reactive dye by persulphate due to the formation of free radicals

EFFLUENT CHARACTERISTICS AFTER TREATMENT

Parameters

Influent Primary treatment

Ozonation

RO Stage I RO Stage II

Permeate

Reject Permeate

Reject

pH 9.88 9.61 6.92 6.03 6.72 5.76 7.04

Total suspended solids, mg/l

167 56 19 6 70 6 124

Total dissolved solids, mg/l

3104 1946 3256 922 9830 196 17828

Chemical oxygen demand, mg/l

586 166 130 26 327 17 754

Biochemical oxygen demand, mg/l

190 41 41 1 16 2 208

Total Hardness, mg/l

96 60 Nil 1080

Chlorides, mg/l 334 636 692 314 108 34 4416

Colour, % purity <10 <10 Colorless Colorless <10 Colourless 10-20

INNOVATIVE TECHNOLOGY Ozonation- used for oxidation of organics and

inorganic, deodorization, and decolourisation

Nanofilteration and Ultrafilteration- difference between reverse osmosis and ultrafiltration/nanofilteration is primarily the retention properties of the membranes

Crystallization- formation of solid crystals from a homogeneous solution; used to recover salts.

Multiple Effect Evaporation- vertical cell in which stainless steel tube is mounted; evaporator systems works on falling liquid film theory.

QUESTIONS PLEASE…