Ecofriendly Conversion of Marble Waste into Value-Added Tiles for Green Building
"Sustainable manufacturing is urgently required nowadays, more than ever before, to overcome current challenges in climate changes, depleting natural resources and polluting environment. Based on the Qatar National Vision 2030 (QNV 2030) and the third Qatari National Development Strategy (2023-2027), converting industrial solid waste in Qatar into value-added products is an important target which should be implemented to ensure sustainable consumption and production patterns as set by the United Nations, in the global goal: SDG 12. Away from dumping in landfills, preserving value of waste and byproduct in Qatari industries is an ideal approach to maximize economic gain, keep clean environment, optimize sustainability and reduce carbon footprint. Upgrading existing industrial procedures and increasing recycling rate should be considered for the production of new or improved quality products.
Marble mining and processing generate around 200 million tons of waste per year worldwide. Quarrying, cutting, sawing, sizing, carving and polishing marbles produce aqueous slurry, sludge, powder or dust wastes from marble materials. These wastes lead to destructive irreversible impacts on ecological systems, the environment, and public health, particularly when they are discharged arbitrarily to the environment or even dumped into the landfills. Converting waste marble powder into alternative marketable products at a lower cost or better performance compared to that for the current existing products will promote sustainable economic growth and development. Marble waste can be used in different applications such as asphalt, road construction, gypsum plaster, cement, aggregates, concrete, mortar, brick making and other building materials. Also, marble waste can be used for replacing the traditional clay, fillers and other conventional materials to manufacture of high-performance hybrid composites. The socioeconomic benefits of producing hybrid polymer composites are not only recycling marble waste but also making a cost-effective sustainable construction material with desired characteristics for green building. The unsaturated polyester is selected as polymeric matrix due to its low cost and good properties. High performance hybrid polymer composites are prepared from unsaturated polyester and then, tested for their mechanical, physical, and thermal properties. In this progress work, we have explored the challenges to produce ecofriendly tiles which are costeffective, durable and suitable for green building. The disadvantages of marble powder-polyester composite are low modulus and insufficient rigidity, shrinkage particularly during curing, low aging resistance, less water resistance compared to metals or high-performance engineering plastics. This project is still in progress. The plan for the remaining work is to use different additives in small amount, without any significant increase in the cost, in order to overcome the challenges and disadvantages of the produced hybrid composite which can be used for manufacturing tiles. The plan could also include to make some tests, with a fixed percentage of marble powder, but testing different resins, such as vinyl-esters and epoxies. For demo testing; two model houses (prototypes) with a size of 60x60x60cm will be constructed. One will be made from the hybrid composite tiles and the second made from traditional tiles. Heat leak test will be conducted in both prototypes by measuring the difference in temperatures which is created between inside the prototype box and the outside surroundings, and the required time to reach thermal equilibrium will be recorded. The longer the time to reach the thermal equilibrium the better the thermal insulation. Reducing the heat leak in green building is one of the most effective method in decreasing the indoor required cooling energy during hot weather. This also can be applicable to the heat leaking out of buildings in a cold weather environment."
