Physico-mechanical characteristics of briquettes produced from composite sawdust admixture using a screw press briquetting machine was investigated. Sample feedstock materials collected has particle sizes varying between 6-8mm with 10-20% powdery components (< 4 mesh). Briquette’s physical characteristics investigated using standard test apparatus and procedures include dimensional stability immediately, 1 hour and 30 days after production, effects of particle moisture and particle size on briquette compressed and relaxed densities. Mechanical characteristics include resistance to gravity and impact, effects of densities on impact resistance index (IRI) and effects of briquette durability in water. Statistical models were used to establish empirical relationships between the feedstock materials (independent variables) and briquette characteristics (independent variables). The physical characteristics of briquettes produced at 12% are loose and brittle with poor dimensional stability, at 10% they are bonded but weak in strength with good dimensional stability while briquettes produced at 8% are wellformed, good colouration with char carbonation, excellent dimensional stability. The compressed density of the briquettes ranges of 490-820 kg/m3. The lower moisture briquettes have high resistance to water dispersion, high impact resistance and excellent storability. Keywords: Characterization, extrusion, briquette, sawmill, sawdust

Improved fluid detection and lithology discrimination using rock properties and attributes cross plots have been attempted using well log data in an Onshore Niger Delta field. Rock properties and attributes were extracted using empirical rock physics models on well logs and used to validate their potentials as pore fluid discriminants. These rock properties and attributes were cross plotted for the primary purpose of investigating their sensitivity to fluid and lithology in cross plot space. V p and V s logs were derived from the inverse of interval transit times of sonic and dipole shear logs respectively. V p /V s ratio, acoustic impedance and porosity were derived from V p , V s and density logs using appropriate relations. The identified depth of reservoir of interest (A2) for Well A and B ranges from 5842 ft to 5964 ft and 5795 ft to 5936 ft respectively. The properties cross plotted comprise V p vsV s, V p /V s vsI p , V p /V s vs Porosity, V p /V s vs Density and V p vs Density. V p vs Density cross plot revealed that the reservoir consists of sand lithology with intercalated shale. V p vsV s shows a linear relationship and does not discriminate fluid in the reservoir. V p /V s ratio vsI p distinguish A2 into hydrocarbon, brine and shale zones. V p /V s ratio vs density and porosity crossplots distinguishes the A2 into gas, oil, brine and shale zones. The analysis validates the fact that V p /V s ratio and their combinations cross plots are more sensitive and robust for fluid discrimination. It also reveals that the ratio of V p /V s is more sensitive to change of fluid type than the use of V p or V s separately.

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ABSTRACT. An electrically operated brush cutter was developed and fabricated to eliminate inherent ergonomic designs and costs of imported brush cutters and also improve performance efficiency. The machine incorporated an electric power pack which provides 4hours of continuous power for cutting, ergonomic design a ground wheel roller was introduced to reduce carpal disorder that could be associated with hand held brush cutters. Machine effective efficiency is rated at 46.67% and the blade cutting efficiency is 87.5%. The minimum height of cut is 1.3mm while the machine is capable of operating at variable conditions. The estimated cost of the machine is N10, 000.00 compare to the cost of imported machines