AbstractThis work involved the production and thermal characterization of biomass briquettes produced by blending a major agricultural waste with coal dust. In the work, nine different compositions of coal dust/groundnut husk briquettes were produced using starch as the binder while Ca(OH2) was incorporated as the de-sulphurizing agent. The ash content, volatile matter, fixed carbon, moisture content, compressive strength, ignition time, calorific value, water boiling test and burning rate were carried out to determine the physical, mechanical and thermal properties of the briquettes produced. The results showed that moisture content values are in the range 2.43 - 6.44%, for compressive strength 7.72 - 10.85 N/mm3, for ash content 24.18 - 29.15 %, for calorific value 21714.17 - 25027.18 kJ/kg, for fixed carbon 16.77-53.22 %, for ignition time 22.23-45.20 s, for water boiling test 1.50-4.99 min and burning rate 16.10-28.32 g/min. These are appreciable values for the thermal properties of the bio-briquettes. Therefore, the agro-wastes briquettes are beneficial for heating purposes rather than open incineration of the wastes.

This study examined potentially toxic elements (PTEs) from poultry feeds. The presence of PTEs in the environment raises health concern because these elements can be toxic, ubiquitous and cannot be degraded to non-toxic forms by any known method and as a result remain in the environment for decades. This is a potential pathway through which these PTEs could easily enter the food chain. Six PTEs (Cd, Cr, Cu, Pb, Mn, Ni and Zn) were determined from four feed types (starter, grower, finisher and layer) from four manufacturers coded A, B, C and D. The samples were prepared, digested and analysed for PTEs using atomic absorption spectrophotometer. The mean concentrations obtained were in the following ranges: 0.49 – 0.76 mg/kg (Cd); 11.9 – 7.90 mg/kg (Cr); 5.10 - 7.91 mg/kg (Cu); 7.17 - 9.47 mg/kg (Pb); 26.9 - 34.9 mg/kg (Mn); 3.80 - 6.50 mg/kg (Ni) and 27.8 - 38.4 mg/kg (Zn). These results were compared with the maximum acceptable concentration for PTEs in feeds as stipulated by the European Union standard and the concentrations of Pb and Ni exceeded maximum acceptable concentration. When concentrations exceed set standard, it implies risk to human health. Thus, the need for continuous monitoring of feed compositions.