Iron oxide bearing wastes (IOBS) are produced at every part of processing stage of sinter, molten iron and steel production. They are hard to handle and in many cases are stockpiled only to be a source of environmental pollution. However, they can be balled into pellets. Pellets characterized by good ballability values are transportable and recyclable as they can withstand stress without disintegrating back to dust. Yet, ballability is affected by certain factors like the grain sizes of the materials, the moisture and binder contents of the ball mix, wettability of the balled materials and the processing perimeters of the granulator. The objective of this research work is to investigate the factors affecting ballability of mixture of iron ore concentrates and iron oxide bearing wastes in metallurgical processing. The parameters under consideration were: grain size of materials, the moisture contents, speed of balling disc, IOBS and bentonite (binder) contents of the balled mix. The investigation was carried out by balling different volume fractions of mix containing iron oxide concentrate and IOBS using a balling disc and testing the resulting balls for green compressive strength using an universal testing machine. It was found that the ballability of the mixture of iron ore concentrate and IOBS increases as grain sizes of the materials reduce but increases as the moisture contents and IOBS content increase up to an optimum value of moisture content in the mix before it starts to reduce. The ballability also increases along with the speed of the granulator (balling disc) within the limit of this work. An increase in ballability with a slight raise in bentonite content in the mix was observed as well.

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Several studies projected that by year 2025, 4.3 billion urban residents will be generating about 2.2 billion tonnes of municipal solid waste per year, over 10% of which will be plastics. The landfills in Nigeria are uncontrolled and do not conform to the international standards of similar operations elsewhere in the world; this makes the disposal of synthetic polymers in the soil even more hazardous. Due to the availability and relative inexpensiveness of Zea mays in Nigeria, this study explores the use of this natural polymer, blended with low density polyethylene (LDPE) as an alternative to synthetic plastics. Biodegradability of the biopolymer blend was observed while buried in loamy sand soil with properties similar to the soil found in the general area of the study. The results showed that a polymer blend with 50% LDPE (50 CoS) by weight had the most uniform weight loss over the period of the study. Under the soil conditions given in the study, 50 CoS also had the steadiest rate of degradation. Hence 50% LDPE (wt.%) blended with Zea mays starch is the optimal ratio with regard to the degradability of biopolymer in loamy sand soil Ota,

This study is focused on the development and characterization of a stir cast Al-Si alloy reinforced with titanium carbide nano-particles. The composite was developed using the stir casting method and the casted samples were prepared with TiC nano-particle at 0.4 (B1), 0.8 (B2), 1.2 (B3), 1.6 (B4) and 2.0 (B5) wt. % of the entire composition, as well as a control sample, and thereafter subjected to tensile and hardness tests. It was noticed that none of the samples at the chosen concentrations brought about a greater hardness value than that of the control sample (Sample A), however they all show a positive trend with an increase in the % wt. of reinforcement bringing about a possibility of increase in the hardness value. This suggests that a further increase above 2.0% of the reinforcement should bring about an increase in hardness above that of the base Al-Si alloy. On the other hand, the tensile strength was significantly increased upon reinforcement. B5 exhibited the highest tensile strength by displaying a transition from needles/plate-like to globular/fibrous morphology.

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Background: Owing to the rising trend of agro wastes, efforts are being geared towards producing environmentally friendly welding flux. This project developed a nano-flux powder (MnO) from banana peel using nano-technology. For the first time, manganese was synthesized from banana peel ash. After that, the nano mixtures were centrifuged and calcinated to obtain nano flux powder. Methods: The surface morphology and physio-chemical properties of the nanopowder produced and control were determined using X-ray Powder Diffraction, Transmission Electron Microscopy, and Scanning Electron Microscopy along with Elemental Dispersive X-ray to analyze its composition. Also, the particle size was obtained using the Digmizer image. Results: The developed nano-flux powder has a mean area of 407.72nm2, a mean perimeter of 51.02nm, and a length of 3.89nm less than the commercial flux. The FTIR revealed the maximum peak of wave number 415z.00cm-1, which shows a broad high concentration than the control with wavenumber 3546cm-1. XRD result shows that manganese oxide is present in the powder with the highest intensity at MnO (110) with Quartz at 2Ɵ = 26o, having a current of 9.26A and hematite at 2Ɵ = 28% having a current 5.34A over the control. From the EDS of qualitative analysis of the powders, manganese and oxygen were present in high quantities in the developed flux with 29.45% and 38.70% than in control with 3.15% and 23.30%, which confirmed the nano-flux as manganese oxide (MnO). The results show that nano-flux powder can be produced from agro-waste with better properties and applications. Conclusion: From the results and discussion, banana peel was used to develop Manganese oxide flux powder, using nanotechnology, and it was characterized alongside commercial flux powder as a control.

This work examines the influence of disc milling duration on the morphological transformation and crystal reorientation of titanium alloy powder with a particle size below 90 µm. The disc milling time was varied from 2 mins to 10 mins, the morphological features of the powders were characterized through the scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffractometer (XRD). From the results, milling time had a significant effect on the morphology and the orientation of phases in the titanium alloy powder. The SEM images revealed a plate-like shape compared with the un-milled powder with a spheriodal shape. It was also observed that the flattening of the particles increased with milling time. This suggests that the powder is ductile. The oxygen content of the particles increased from 3.4 wt. % before milling to above 10 wt. %. XRD results showed that the milling time did not bring about a new phase and in the position of maximum diffraction intensity, which occurred at 2θ equal to approximately 40.6°. However, there was a decrease in the crystallite size while the lattice strain became higher as milling time increased.

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