Potential Utilization of Textile Dyeing Sludge, Pet Granules, and Fly Ash in Lightweight Concrete Block

Abstract

The rationale of this study is to appraise the technological possibilities for incorporating textile dyeing sludge, fly ash, and polyethylene terephthalate (PET) granules in the production of lightweight concrete blocks. Sludge is a material being generating from effluent treatment plants (ETPs), which has detrimental effects on the environment. Fly ash consists light particles, and its deposition on leaves inhibits the normal transpiration and photosynthesis of plants. Fly ash also affects the physicochemical characteristics of the soil. Another waste material is PET bottles. A non-biodegradable material that pollutes the soil and creates negative impacts on the environment as well as aesthetics of aquatic living organism. Replacement of these three wastes by sand and stone chips in several combinations with cement has been studied in this study. The compressive strength was found at 2.62 kg/mm2, where 15% sand was replaced by waste materials (fly ash, dyeing sludge, and PET granules). The compressive strength increased up to 45% replacement of sand by waste materials, and maximum strength was 3.24 kg/mm2. Strength was found at 2.13 kg/mm2, where PET granules replaced 15% of stone chips. The compressive strength decreased drastically as the PET increased. The control sample was not mixed with waste material, and 2.71 kg/mm2 compressive strength was quantified. There was the possibility of leaching of heavy metals due to the presence of heavy metals in sludge. The heavy metal concentrations for the combination of maximum amount of sludge were measured in 7th, 14th, 21st, and 28th days. Zn, Ni, Pb, and Cr had not detected except Cu. Cu was detected from 21st and 28th days curing water, and these were 0.0043 and 0.0081 mgkg−1. In light of this study’s findings, it can be recommended that, up to 15% sand can be replaced with sludge, PET granules, and fly ash without any significant deterioration of properties required of a good quality lightweight concrete block.