Brick wastes are generated as a result of demolition, and may be contaminated with mortar and plaster. Brick wastes are sometimes blended with other materials like timber and concrete. Currently, bricks are recycled by crushing and using as filling materials.
Concrete wastes can be generated due to demolition of existing structures and testing of concrete samples etc. commonly recycling measures of concrete wastes are used crushed concrete as aggregate.
The crushed concrete aggregate has been used as a replacement to natural aggregate in new concrete, and it also has been employed in the construction of road base and trenches.
Ferrous metal is another type of wastes which not only highly profitable but also can be recycled nearly completely. In addition, ferrous metal can be recycled multiple times.
Fig. 1: Ferrous Metal
Masonry waste is produced as a result of demolition of masonry buildings. It can be recycled by crushing the masonry waste and used as recycled masonry aggregate.
A special application of recycled masonry aggregate is to use it as thermal insulating concrete. Another potential application for recycled masonry aggregate is to use it as aggregate in traditional clay bricks.
Aluminum, copper, lead, and zinc are examples of nonferrous materials wastes produced at construction sites. The majority of these materials can be recycled.
Paper and paper board is another type of waste materials which is estimated to comprise one-third construction and demolition wastes by volume. These waste materials are recycled and reprocessed to produce new paper products.
Fig. 2: Paper and Cardboard Wastes
The plastic wastes are best possible for recycling if these materials are collected separately and cleaned. Recycling is difficult if plastic wastes are mixed with other plastics or contaminants.
Plastic may be recycled and used in products specifically designed for the utilization of recycled plastic, such as street furniture, roof and floor, PVC window noise barrier, cable ducting, panel.
Fig. 3: Recycling Plastics
Timber waste from construction and demolition works is produced in large quantity all over the world. Whole timber arising from construction and demolition works can be utilized easily and directly for reused in other construction projects after cleaning, de-nailing and sizing.
Fig. 4: Recycling Timber