The influence of fiber density and cellulose content of banana and rice straw fibers on fiber processing and flexural strength

Abstract

Excessive use of wood based fibers and inefficient management of forest reserves contribute critically to shortage of trees. Abandoned biomass, banana and rice straw, are considered as alternatives for wood in lamina or ply composite industry. Key objective of the study is to reduce the fiber strands into particulate mechanically. It also delved on investigating the influence of fiber density and cellulose content on fiber particulate recovery and flexural strength. In line with this, the study also investigated whether natural fibers in particulate form can be consolidated in sand cement mortar. Toward this end, fibers were extracted and processed mechanically through hammer and milling actions. Buoyancy principle is utilized to find the specific gravity of the fibers then converted into fiber density. Fiber cellulose content is resourced. Sample deflection is obtained from three point bending test. Flexural strength is calculated utilizing the theoretical deflection equation. An attempt is made to integrate the fibers in sand cement composite lamina. Samples are prepared and conditioned as air dried.

Results indicated banana fiber exhibited higher density than rice straw fiber. Fiber particulate as produced mechanically showed that banana fibers are coarser than rice straw fibers. When milled and screened, banana fibers exhibited higher recovery rate of 89.4 percent, compared to rice-straw with 63.1 percent. Findings also revealed that flexural strength increased with increasing specific cellulose, ratio of cellulose content and fiber density. Particulate banana and rice straw fibers at 30 percent by weight are better consolidated in 1:3 cement sand mixture. Thus, cellulose content and density of the fibers are important parameters in mechanical extraction. The degree of difficulty and rate of recovery are relatively proportional to these parameters. Consolidating 30 percent of fiber particulate with sand and water-cement ratio was successfully attempted. The fibers in particulate form exhibited characteristics conducive for ply board production.