Faculty of Technical Education

Assessment of occupational health and safety of wood machining operation at a wood processing and marketing centre in Ghana

Fri, 01 Jan 2021 00:00:00 GMT

Assessment of occupational health and safety of wood machining operation at a wood processing and marketing centre in Ghana Donkoh, M.B. The woodworking industry is considered to be a risk-prone working environment since every working item and materials used present potential danger through accidents or health risk. Workers in the woodworking industry are also faced with potential accidents that can be caused by flying wood chips and some parts of the machines that may be broken. This study assessed the occupational health and safety hazard associated with wood machining operation in a selected wood processing and marketing centre in Ghana. The study adopted mixed approach design of observation, cross-sectional survey, experimental and interventional design. Positivism and phenomenologist philosophical paradigms as well as inductive and deductive research approaches were used. The data was analyzed using Statistical Package for Social Scientist. Findings from the study indicate that none of the wood processing machines assessed had operator’s manual, safety code or signs on them. Most of the safety parts were absent. However, few were improvised. The mean ratings of machine operator’s adherence to practicing occupational health and safety were lower than the theoretical mean of 3.0. This implies that the machine operators do not practice occupational health and safety. The study also revealed that, there was heavy metal concentration of airborne particulate such as Arsenic, Cadmium, Copper, Iron, Lead, Manganese and Zinc in the sawdust the workers were exposed to. Metal concentration levels exposed to by the workers were above Occupational Safety and Health Administration and Environmental Protection Agency permissible exposure limits (PEL) thresholds. On workers exposure to sawdust, the result indicates that workers do experience headache, nausea, eye and skin irritation, shortness in breathing and coughing. Again, the operation and activities of the woodworkers could significantly influence their exposure to sawdust. Additionally, the study revealed that the woodworkers were not provided with personal protective equipment during their University of Education,Winneba http://ir.uew.edu.gh xix operations. Furthermore, the study revealed that training could significantly influence the woodworkers’ practice of occupational health and safety in the wood processing industry. The outcome of this study suggests that the management of the enclave studied need to do more to enforce practice of safety, especially the use of personal protective equipment, to reduce hazards and injuries associated with wood processing industry. A Thesis in the Department of Construction and Wood Technology Education, Faculty of Technical Education, submitted to the School of Research and Graduate Studies, University of Education, Winneba, in partial fulfilment of the requirements for award of the Doctor of Philosophy (Wood Science and Technology) degree

Logging residues quantities, and some properties of solid and finger-jointed lumber of stem (off-cuts) and branch wood of some Ghanaian tropical hardwoods

Wed, 01 Jan 2014 00:00:00 GMT

Logging residues quantities, and some properties of solid and finger-jointed lumber of stem (off-cuts) and branch wood of some Ghanaian tropical hardwoods Dadzie, P.K The purpose of this study was four-fold: First, to estimate merchantable logging residues left in the forest after logging; second, to investigate the natural durability of stem and branch wood of five species; third, to compare the bending strength of solid and finger-jointed lumber; and finally to investigate the influence of anatomical properties on natural durability and mechanical properties of wood. The five wood species were Entandrophragma cylindricum (sapele), Entandrophragma angolense (edinam), Khaya ivorensis (mahogany), Terminalia superba (ofram), and Pterygota macrocarpa (koto/kyere). Forest residues were quantified with Smalian‟s equation, natural durability test was measured on percentage weight loss in accordance with EN 252-1989, whereas bending strengths of solid and finger-jointed lumber (produced with PVA adhesive) were evaluated in accordance with BS 373-1957, and the anatomical properties assessed using IAWA Committee protocol and using ImageJ software. Results showed 25% of merchantable logging residues of felled trees were left in the forest unextracted. Unlike branchwood of mahogany, ofram and koto whose natural durability were comparable to their stemwood, branchwood of sapele and edinam dried to 9±3%MC were significantly (p<0.05) better than their stemwood counterparts. Bending test showed significant (p<0.05) MOE differences from 9.4% to 23.5% higher in solid branchwood of edinam, mahogany and ofram, whereas MOR differences were from 16.5% to 23.5% higher in branchwood of edinam and mahogany compared to their stemwood counterparts with MC and wood type having significant effect (p=0.000). Branchwood finger-jointed lumber combinations produced joint efficiencies in MOE ranging from 59% to 110%, and those in MOR ranged from 30% to 68%. Expectedly, finger-joint efficiencies in MOE and MOR correlated inversely with wood density. But unlike the MOEs, MORs of all finger jointed combinations were significantly lower (p<0.05) than those of stemwood of their respective species. As a characteristic of hardwoods, sizes and quantities of some wood cells were either significantly (p<0.05) more or less in stemwood than in branchwood. As expected, fibre and parenchyma proportions respectively correlated inversely and positively with percentage weight loss. Also, fibre and vessel proportions correlated positively and inversely respectively with MOE and MOR. In conclusion, wood residues are of substantial quantities, and solid wood or finger jointed lumber of branches are not inferior to those of stemwood of the same species and therefore branches could be extracted for use to supplement stemwood so as to help in addressing the challenge being posed by timber shortages to industry and also help in reducing the depletion rate of Ghana‟s forest cover. A Thesis in the Department of CONSTRUCTION AND WOOD TECHNOLOGY EDUCATION of FACULTY OF TECHNICAL EDUCATION, Submitted to the School of Graduate Studies, University of Education, Winneba in partial fulfilment of the requirements for award of the Doctor of Philosophy (Wood Science and Technology) degree. JULY, 2014

The potentials of Bambusa V. Vulgaris (bamboo) biomass as feedstock to produce biofuels

Mon, 01 Jan 2018 00:00:00 GMT

The potentials of Bambusa V. Vulgaris (bamboo) biomass as feedstock to produce biofuels Appiah-Yeboah, J Many technologies are now being prepared worldwide to convert stored energies in lignocellulosic materials such as bamboos to provide bioenergy in the form of heat, electricity, gas and transport fuel. This study investigated the fuel properties of bamboo (Bambusa vulgaris Schrad. ex J. C. Wendl. var. vulgaris) feedstock to produce biofuels – heat, transport fuels, gas and electricity. In all, 1 200 samples were tested for morphological properties, physical properties, proximate analysis, ultimate analysis and ash elementals (minerals) analysis. The results showed that there is an interaction between ecological zones and the growth stages. The clump sizes ranged from 512cm to 622.33cm. However, there was no significant difference at 5% significance level among the three zones. Culm heights ranged from 9-14m, internode distance from 35-38mm, culm diameter from 8-10cm and culm wall thickness and 9-13mm were observed across the ecological zones. The culm wall thickness decreases from the base (9.10 cm) to the top (8.43 cm). The calorific value increases with increase wall thickness of the culm. The mean values for density ranged from 395 to 745 kg/m3 , bulk density ranged from 0.12 to 0.52 g/m3 , calorific values ranged from 12 to 18 MJKg-1 . Increase in the bamboo culm wall thickness has correspondent increase in density. The ash content ranged from 0.48 to 3.40%. The mean values for VM (76 – 84%), FC (14-16), C (46-52%), H (6.4-6.6%), N (0.12-1.3%) and O (40- 44%). The mean values for heavy metals (ppm) were Cu (1.3-7.6), Zn (2.95-4.87), Pb (0.04- 0.10), As (0.07-0.11), Ni (0.64-1.33) and Cd (0.79-4.21). The mean values for the minor metals (ppm) were Ca (26-29), K (0.6-2.4), Mg (0.13-0.18), P (0.06-0.18), Na (0.6-1.1), Al (0.14-0.21) and Fe (0.20-0.17). Mature and dead bamboo culms in any zone can be used for the production of charcoal and biofuels. The leaves of the studied bamboo specie had higher ash, nitrogen and cadmium contents than the culms. Removal of the leaves therefore is necessary when using bamboo for biofuels. A THESIS IN THE DEPARTMENT OF CONSTRUCTION AND WOOD TECHNOLOGY EDUCATION, FACULTY OF TECHNICAL EDUCATION, SUBMITTED TO THE SCHOOL OF GRADUATE STUDIES, UNIVERSITY OF EDUCATION, WINNEBA IN PARTIAL FULFILMENT OF THE REQUIREMENT FOR AWARD OF THE DOCTOR OF PHILOSOPHY (WOOD SCIENCE AND TECHNOLOGY) DEGREE. OCTOBER, 2018

Optimizing saw teeth deflection and lumber thickness variation through precision engineering approach

Sun, 01 Jan 2006 00:00:00 GMT

Optimizing saw teeth deflection and lumber thickness variation through precision engineering approach Okai R. [No abstract available] Okai, R., Department of Technology Education, University of Education, Winneba, Kumasi Campus, P.O. Box 1277, Kumasi, Ghana