About the Possibility of Recycling Water Treatment Sludge in the Wood–Cement Composites Production

Abstract

The paper presents the results of a study of the possibility of recycling water treatment sludge in the production of wood-cement composites. Sludge is formed during the treatment of sewage, containing industrial machine oil, with a sorption material, based on thermally modified chestnut tree waste (CTW). It was found that the addition of sludge leads to an increase in the density of the samples. Thus, the samples without the addition of sludge have an average density of 860 kg/m3, samples with the addition of sludge in an amount of 10 mass% - 875 kg/m3, 20 mass% - 879 kg/m3, 30 mass% - 882 kg/m3, 42 mass % - 887 kg/m3. Studies of the change in water absorption of samples, depending on the amount of sludge added, showed that the values slightly decrease for samples containing sludge, what is explained by the presence of oil in the mixture. The compressive strength of the samples with the addition of sludge in the amount of 42 mass% was 3.1 MPa, what corresponds to the regulatory requirements for a wood cement composites.