Abstract:
Human activities often generate solid wastes such as plastics and egg shell wastes. Disposal of these wastes is usually a problem. The aim of this study was to investigate the feasibility of using plastic and egg shell wastes together with white cement in the production of floor tiles. The waste was collected from kitchens and waste disposal facilities within Juja constituency, Kenya. The materials were cleaned and dried; and plastics were shredded while egg shells were crushed. Waste materials were then mixed with white cement in different proportions. Compressive strength tests were carried out to determine the suitability of using such solid wastes in making floor tiles. Crushed egg shells passing through the 1.2 mm sieve and shredded plastics with an average diameter of to 1 to 2 mm were used. Cubes were cast and cured for 28 days. The compressive strength of the cubes was tested using a universal testing machine. The study found that addition of up to 50% cement resulted in more than 10 fold increase in the compressive strength of the cast cubes. Addition of plastics decreased the compressive strength of the cubes while addition of egg shells had insignificant effect on compressive strength. Increasing the quantity of plastics and egg shells resulted in elevated water absorption, while larger quantities of cement resulted in reduced water absorption. Increasing the quantity of egg shells and plastics resulted in reduced density. With the presence of plastics, abrasion resistance increased and the tiles became less brittle. It is concluded that egg shells can be used as filler material in the manufacture of floor tiles. Because of the tendency of plastics to reduce the compressive strength of tiles, they should be used
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cautiously. The study has established that use of plastic and egg shell wastes in the manufacture of floor tiles is a viable waste reduction option. However, further studies are necessary to establish the chemical interactions involved in floor tile production systems where household and industrial wastes such as plastics and egg shells are used.