A Study on the utilization of waste cement - bonded wood particle board as a raw material and a secondary fuel in cement manufacturing

Yılmaz, Mustafa
A considerable amount of waste is obtained as a result of edge-cutting operations during cement-bonded wood particle board (CBWPB) manufacturing. This waste material which basically contains wood chips and hydrated cement has to be disposed of and does not have any economical value. However, it can be burned in cement rotary kilns and may result in energy savings to a certain extent due to the presence of wood particles as a secondary fuel and since the hydrated cement may be decomposed and then reform clinker compounds during the calcination process. In this experimental study, the possibility of using waste CBWPB in cement manufacturing and its effects on energy consumption and cement characteristics will be investigated. The reference mix, corrective limestone, CBWPB waste and coal, were used as raw materials to prepare six different raw meals whose chemical compositions was similar to reference mix. All six raw mixes (including the reference) were calcined under the same conditions to produce clinkers. The compositions and micro structure of the clinkers obtained were comparatively analyzed by wet analysis, XRF and XRD techniques. Cements were obtained by intergrinding the clinkers with 5% (by mass) gypsum rock and standard tests were carried out on each of the cements. In addition to these, since CBWPB waste contains wood about 30% by weight, its contribution to fuel consumption during clinker production was also analyzed. The test results revealed that CBWPB waste can be used as a cement raw material since CBWPB waste has the similar chemical composition with the reference raw mix. CBWPB, which contains about 30% (by mass) wood, contributes to the heating process during calcination and results in lower amount of primary fuel requirement.