Optimum manufacturing parameters for compressed lumber from oil palm (Elaeis guineensis) trunks: Respond surface approach

The objective of this investigation was to evaluate optimum manufacturing parameters to produce compressed lumber from oil palm (Elaeis guineensis) trunks. Experimental samples were made using steaming time, pressure, pressure time and temperature ranging from 2 to 4 h, from 5 to 12 MPa, from 20 min to 60 min and from 100 °C to 200 °C, respectively. Compression and recovery ratios of the specimens were determined employing Response Surface Methodology (RSM) approach within the scope of Central Composite Design (CCD) computer program. Experimental and calculated values were compared to each other. Based on the results of the work, the specimens steamed for 2 h before they were compressed using a pressure of 11.16 MPa at a temperature of 200 °C for 60 min resulted in optimum conditions. Measured and calculated compression and recovery ratios of the samples showed 0.70 and 0.83 correlation coefficient values, respectively.