Utilization of Textile sludge in combination with fly ash for the production of construction materials

Investigators Prof. N. Selvakumar and Dr. V.R. Giridhar, Dept of Textile Technology Prof. V. Murugesan, Department of Chemistry Prof. G.M. Samuel Knight, Prof. Devadas Manoharan, Dr. A. Chinnaraja, Structural Engineering Prof. A. Navaneetha Gopalakrishnan, Centre for Environmental Studies Collaborating Institute Environmental Technology Division, CLRI, Chennai Objective Textile Industry occupies a unique place in our country and is the second largest employment generator after agriculture. Textile industry was one of the earliest industries that came into existence in India and it accounts for more than 30% of the total exports. It comprises of spinning, weaving, chemical processing and apparel manufacturing sectors. Amongst these sectors, textile chemical processing assumes a paramount importance as it adds value addition to fabrics in terms of imparting colour and functional characteristics to the fabrics. But in this process of value addition, a significant amount of the effluent is generated which needs to be treated and during the process of this treatment significant amount of sludge is generated. It has complex chemical chemistry and pathogenic which may lead to physical and psychological problems to human beings if disposed as landfill. Similarly, the disposal of fly ash generated from combustion of coal is also a major concern as it poses health hazards such as silicosis and lung damage. It is estimated that 100 million tonnes of fly ash is being generated annually in India and by 2015, disposal of coal ash would require almost one square meter of land per person or one thousand square kilometer. The problem with fly ash lies in the fact that, not only, does its disposal require large quantities of land, water, and energy, but its fine particles, if not managed well, by virtue of their weightlessness, can become airborne leading to the environmental hazards. The cement industry contributes to about 5% to global anthropogenic CO2 emissions, making the cement industry an important sector for CO2 emission mitigation strategies. It should be mentioned here that approximately 780 kg of CO2 is produced for every 1000 kg of cement produced in a factory. Hence there is a pressing need to reduce the usage of cement to reduce the CO2 load in the atmosphere. In the present project it is planned to explore the possibility of usage of textile sludge along with fly ash for the production of construction materials.

Strategy and Methodology In most of the reported work in the literature, the utilization of sludge from domestic and industrial waste water treatment plant is concentrated on

* retrieving the organic compounds from the sludge
* using it as an aggregate in concrete o using it in the place of cement in concrete
* the production of ceramic bricks and tiles and
* mixing it with clay to produce building bricks. However, only a very limited work has been carried out on the utilization of textile sludge in the production of construction materials. Taking into consideration  
   the above mentioned facts, it is planned in the present proposal
* To explore the utilization of textile sludge in the construction materials.
* To identify and carry out detailed analysis of the composition of textile sludge
* To design an efficient process to remove the salts and other auxiliaries present in the textile sludge that will affect the quality of construction materials
* To combine the textile sludge along with fly ash and explore its possibility for the production of construction materials
* To compare the properties of the developed construction materials with that of existing materials and
* To demonstrate the usage of the developed construction materials. Expected major outcome It is planned to utilize the construction materials developed with textile sludge and fly ash for
* Pavement blocks
* Pre-cast panels
* Flooring blocks
* Road works
* Foundation concrete
* Filling in material for road works.