A range of artificial aggregates has been developed from incinerated sewage sludge ash. The ash is either pelletized or slabbed and subsequently fired until it sinters and expands to form lightweight products which are later graded for use as aggregates in concrete. From the standard tests conducted on size grading, bulk density, absorption and fracture strength, it appears that both the pellets and slabs are potentially suitable as lightweight aggregates in concrete. Preliminary studies on concrete incorporating these aggregates support this hypothesis. No studies of potential containment release at high temperature was made during these studies.
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Tay, J.H. & Yip, W.K. (1987). Lightweight concrete made with sludge ash. In Proceedings of the international conference on the Design and Construction of Non-Conventional Structures. Vol. 2 London. pp. 205.
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