Cement Manufacturers Association

51 Way Forward Some studies show that natural fine aggregate can be reduced to a certain limitation by using the crushed WPCB powder as a replacement with 15%, 20% and, 25% by weight. It is found that the strength of the concrete is improved, and powdered non-metallic WPCB can be partially used as fine aggregate replacement. Acknowledgments This research work was assisted by Ms. Stuti Banerjee and Mr. Vishal Poriya, 8th semester students of Department of Environment, LD Engineering College, Ahmedabad-380015. References 1) https://www.weforum.org/agenda/2019/01/ how-a-circular- approach-can-turn-e-waste- into-a-golden-opportunity/ 2) https://www.ablcircuits.co.uk/blog/what-are- printed-circuit- boards-made-of/ 3) Environmental Impact of Uncontrolled Disposal of E-Wastes *L. Nageswara Rao Associate Professor, Department of Chemical Engineering, R.V.R.& J.C. College of Engineering, Chowdavaram, Guntur,Andhra Pradesh-522 019,India 4) https://www.researchgate.net/ publication/272668735_Review_Cur rent_Status_of_Recycling_of_Waste_Printed_ Circuit_Boards_in_India Findings Table 2: (Compressive strength of the trial mixture at 7 and 28 days) Cube Compressive strength at 7 days (in N/ mm2) Compressive strength at 28 days (in N/mm2) Compressive strength at 28 days (in N/mm2) as per IS 456: 2000 (Reaffirmed in 2021) Cube 1 23.34 30.78 25 Cube 2 21.62 30.88 25 Cube 3 21.98 29.84 25 For the trial mixture mentioned in Table 1. The slump value obtained was 110mm.The minimum compressive strength for a standard M25 concrete block at 7 days must be 16.25 N/mm2 and at 28 days must be 25N/mm2. The CTM values obtained for this trial mixture are mentioned in Table 2. Thus, it can be said that replacing 10% river sand by crushed WPCB, not only retains the standard strength but also gains 22% strength over regular M25 grade of concrete. Also, by using powdered non-metallic PCBs replacing the fine sand, we can save Rs. 350 on every Ton of sand replaced. Also, a study conducted for testing, the reactivity of the material shows that it is non-reactive towards diluted as well as concentrated acid. Thus, it can be concluded that over a period the material will not leach any toxins. The test results show in fig.6 Fig.6. Reactivity test using Conc. acid