This kind of recycling is, however, a far cry from the closed loops of an ecological economy. Establishing such loops involves a focus on deconstruction rather than demolition, where construction and even manufacturing processes are designed with recycling and reuse in mind. One step in this direction is the establishment of four streams within the concrete-masonry category of demolition: 1. undiluted concrete rubble: which is thermally treated, producing gravel, sand and cement stone, with some steel. 2. undiluted masonry rubble: which is thermally treated, yielding mortar, bricks and brick pieces. 3. the mixed stony fraction, consisting of concrete rubble and masonry rubble of ceramic bricks and sand-limestone bricks. Decontaminated granules are obtained, used as coarse aggregate for concrete, fine fraction for a sand substitute, with only a small sludge fraction to be disposed of. 4. Mixed C&D waste: demolition waste not separated at source is sorted in an additional process. Gypsum and hazardous materials are separated by advanced detection and separation techniques. The hazardous wastes have to be disposed of; the gypsum recycled. The remaining material is divided into a heavy stony fraction and a light combustible fraction. The stony fraction is treated with the mixed rubble, The combustible fraction is reprocessed to obtain a fuel for the thermal processing plants. These steps move concrete and masonry from waste management to chain management, making more comprehensive recycling of both possible (Mulder, 2000).