L textile industry

L-27Textile IndustryTextile Industry

Industrial Waste Treatment

Introduction

Textile mill uses cotton, wool or synthetic fibers.Waste water generated depends upon Waste water generated depends upon type of fiber used.The pollutants in the wastewater include

- The fibers used and - Chemicals used in processing

Cotton Textile mill

An integrated textile mill produces it yarn from raw cotton.Production of yarn from raw cotton includes steps such as

- Opening and cleaning- Opening and cleaning- Picking- Carding- Drawing- Spinning- Winding and wrapping

All these are dry operations and

does not produce any liquid waste

The entire waste is generated from following operations

- Slashing- Scouring All these are wet - Scouring- Desizing- Bleaching- Mercerizing- Dyeing and finishing

All these are wet operations and produce liquid waste having

varying properties

Yarn manufacturing

RAW

Carding and combing

Wet processes

Wet Process in textile mill Chemicals used

Scouring and Desizing(50% of total pollutional load)

Enzymes, caustic soda, soda ash and detergents

Bleaching (10 % load) Peroxides and hypo chlorides

Mercerizing (small quantity Caustic soda Mercerizing (small quantity of waste)

Caustic soda

Dyeing Variety of dyes (reactive,vat, sulfur, basic etc), caustic soda etc

finishing Starches, dextrines and synthetic waxes, resins etc

Composition of composite cotton textile mill waste

Your Subtopics Go HereCharacteristics Value

pH 9.8 - 11.8

Total alkalinity 17.35 mg/lit as CaCO3

BOD 760 mg/lit

COD 1418 mg/lit

Total Solids 6170 mg/lit

Total Chromium 12.5 mg/lit

Treatment alternative

Treatment alternative

Oxidation Pond

Objective Questions

1. For treatment of textile waste, neutralization tank is needed because of __________nature of wastewater.

2. pH of textile mill waste is in the range of 2. pH of textile mill waste is in the range of ____.

3. Pick out odd one w r t textile millDesizing, quilling, dyeing, proportioning

Theory Questions

Q1. Draw a manufacturing process flow sheet for textile industry. Also mention sources of wastes.

Q2. Give general characteristics of textile Q2. Give general characteristics of textile mill waste.

Q3. Discuss treatment alternatives for textile mill waste.