Abstract

Textile industry is one of the oldest and largest sectors in India. The exports for the year 2007-08 stood up to $20.5 billion. Even it isa value adding industry, it has several environmental impacts causing land andwater pollution with toxicity. Effluent sludge waste management becomes a bigproblem nowadays. Except engineered landfills, rest of the methods for dumping,leads ground water contamination and there by other socio-economic impacts.Many studies have been conducted in this area and reported that the pollutionlevel is high in ground water and nuisance due to dumping in the treatmentplant area premises. There is a growing need to find alternative solutions forthe sludge management. In the present study, an attempt has been made to utilizethe textile ETP sludge (dry) in making of construction materials. Even toanalyze the sludge, process variables for particular sludge generation can bestudied. For inducing strength materials like fly ash, silica fume can be used.Textile sludge was incorporated in fly ash brick manufacturing and it wasobserved that with increase in sludge content, there is a decrease incompressive strength of bricks. Pulverized and sieved bricks show bettercompressive strength when compared with pulverized form and grinded form. Thereis increase in compressive strength with increase in sand, fly ash, cement andquarry dust proportion.

Keywords: Sludge, sand, Fly ash, quarry dust, cement,compressive strength

1. Introduction

The textile units are scattered all over India; out of 21,076 units, Tamilnadu alone has 5285 units (Bal et al, 1999). Textile industry involves processingor converting raw material/fabric into finished cloth materials employingvarious processes, operations and consumes large quantities of water andproduces extremely polluting waste effluents. Textile industry is one of thewater intensive industries, which consumes large quantities of water forvarious processes and discharge equally large volumes of waste water containinga variety of pollutants. In textile industries, all the three types of wastesi.e. liquid, solids and gaseous are generated and the liquid effluent isessentially a mixture of dissolved, colloidal and suspended materials. Thesolid waste usually comprises of fibre/ yarn/ scared from spinning unit, wastefabric, packaging materials and sludge from effluent treatment plants. Thegaseous waste is generally produced by volatile reactants/by products and thegases from boilers.

There is more number of textile industries in Erode andTiruppur District of Tamilnadu. According to recordsof the Tamilnadu state pollution control board (TNPCB), there are 830 unitsengaged in textile industry processes in Tiruppur. These industries haveestablished eight common effluent treatment plants (CETPs). About 200 tons/dayof textile sludge are generated in Tiruppur. Although some of the sludge isdisposed in an engineered landfill, much of the sludge is openly dumped, whichleads to soil, surface water and groundwater contamination. The inorganic saltsand toxic metals in the sludge pose a threat to residents (Thomson etal, 1999; Palanivelu and Rajakumar, 2001). There is a growing need to findalternative solutions for textile sludge management. Asper TNPCB records, there are about large number of units engaged in textileindustry processes in India. These industries have established several commoneffluent treatment plants and several individual effluent treatment plants. Itis estimated that when these units function to full capacity 400 million tonsof sludge is generated during the treatment process consisting of coagulation(by addition of aluminium/iron salts), flocculation and liquid/solidseparation. The sludge produced is classified as hazardous, as per categoryNo.12 of earlier hazardous waste, 1989 rules of our country. The recent amendedrules of January 2000 also classify the sludge as hazardous. This sludgecreates more negative impacts in many ways as far as the correct disposaltechniques are not adopted.

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The authors are associated with Department of TextileTechnology, A. C. College of Technology, Anna University, Chennai, India