The present paper reports on the results of some experiments dealing with the recycling of mixed cathode ray tube (CRT) glass waste in the production of high-strength mortars. Waste CRT glass cullet was previously milled, and sieved, and the only fine fraction was added to the fresh mortar in order to replace part of the natural aggregate. The addition of superplasticizer was also investigated. All hydrated materials displayed high compressive strength after curing. Samples containing CRT mixed glass showed a more rapid increase of strength with respect to the reference compositions, and materials with a superplasticizer content of 1% showed the best overall performance due to the favourable influence of the small glass particles which increase the amount of silicate hydrated produced. The induced coupled plasma (ICP) analysis made on the solutions, obtained from the leaching tests, confirmed the low elution of hazardous elements from the monolithic materials produced and consequently their possible environmental compatibility. 1. Introduction CRT glass waste includes that from TVs, PC monitors and other monitors used in special applications, and waste from the original assembly process. Waste glass from PC and TV monitors will begin to decline as a direct consequence of the emerging flat screen display technology; nevertheless, it seems reasonable to assume that an amount of CRTs from all sources is likely to continue to enter into the waste stream in the coming years. Studies have shown that when CRTs are disposed of in landfill sites, leaching processes from the crushed glass cullet may contaminate ground water. This is a major driving force for CRT recycling. Moreover, it must be pointed out that CRT waste does not contain only glass but also other materials which concur with the CRTs assembly, such as ferrous and nonferrous metals and plastics. The Waste Electrical and Electronic Equipment (WEEE) directive sets strict regulations for recycling or recovery when materials derive from equipment containing CRTs. Such norms must obviously be coupled with those reported by the European Waste Catalogue which classifies CRTs as hazardous waste and makes landfill disposal of CRT materials costly. The great amount of CRT waste produced all over the world implies that its recycling is presently necessary not only due to the rising cost of landfill disposal, which is reflected on the cost of new CRTs produced, but also as a consequence of the “zero-waste” objective which must be the final goal of all future human activities. Mixed CRT glass (funnel, neck and
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