Abstract: Pyrolysis being an efficient process through which biomass materials are converted to biochar and pyroligneous acid can be easily achieved by using an efficient pyrolysis system. These pyrolysis products can be used as source of energy for cooking, soil amendment or as biopesticide/biofertilizer. The aim of this study was to design, develop and test a pyrolysis system in production of biochar and pyroligneous acid from forest wastes (twigs of acacia, eucalyptus, and black wattle). Testing of the developed pyrolysis system was based on the production and quality of biochar and pyroligneous acid. The biochar quality was based on its moisture content (MC), volatile matter (VM), ash content (AC), fixed carbon (FC) and pH while for pyroligneous acid, this was based on the pH and density (ρ). The pyrolysis system designed and developed had a carbonization kiln (diameter = 0.5 m and height = 1 m) and pyrolysis smoke condensation system (surface area = 1.16 m2, radius = 0.16 m, 2 number of coiling tubes, height = 1 m, outer chimney/pipe diameter = 0.18 m). The developed pyrolysis system resulted into an average biochar production of 37.31% and 24.90% of pyroligneous acid. The biochar produced had an average MC = 9.1%, VM = 28.8%, AC = 6.9%, FC = 55.2% and pH = 6.7 while the pyroligneous acid had an average ρ = 1.02 gcm-3 and pH = 3.08. This approach of carbonizing agroforestry materials using the developed pyrolysis system enhances diversification of products by capturing what would otherwise be wasted to produce biofuel, bio-fertilizer, and bio-pesticide. This would result in environmental conservation and serve as source of livelihood when these products are marketed.Abstract: Pyrolysis being an efficient process through which biomass materials are converted to biochar and pyroligneous acid can be easily achieved by using an efficient pyrolysis system. These pyrolysis products can be used as source of energy for cooking, soil amendment or as biopesticide/biofertilizer. The aim of this study was to design, develop and tes...Show More
Abstract: The abuse of agrochemucals in agricultural practise in order to boost food production has generated environmental concern in terms of their residues. This study was carried out to determine pesticide residues of plantain and banana from Benue State, Nigeria due to unregulated applications of pesticides, leading to MRL non-compliances. QuEChERS and buffered ethyl acetate extraction methods were employed for diverse range of pesticides in plantain and banana, followed by selective identification and quantification of the residues using GC-MS technique. The method was evaluated evaluated for 23 organochlorine pesticides. The results of analysis showed that Plantain contains a wide range of pesticide residues with the highest BHC 2.4×10-5 ppb and Endosulfan 1 0.2×10-5 ppb, being the lowest in residues. Banana shows slight range with BHC 1.6×10-5 ppb, the highest and Methoxychlor 0.6×10-5 ppb, the lowest residues. This result showed that their limits of quantification were 0.1-10µg/g, with recoveries of 70-120%. The method provided superior performance in terms of precision, and recovery of the spiked and incurred residues with similiar productivity. Generally, the findings revealed samples of plantain and banana showed some degree of contamination and it is adviseable banned pesticides should not be sold in Benue State any more.Abstract: The abuse of agrochemucals in agricultural practise in order to boost food production has generated environmental concern in terms of their residues. This study was carried out to determine pesticide residues of plantain and banana from Benue State, Nigeria due to unregulated applications of pesticides, leading to MRL non-compliances. QuEChERS and ...Show More
Abstract: Waste Stabilization Ponds (WSP) provide both cost-effective and high-performance wastewater treatment benefits in the tropical regions. The 3-month sludge settling behavior in the Kibendera WSP in Ruiru, Kenya, was studied between July and September 2022. The study aimed at determining the sludge volume index (SVI) and hindered settling velocity during the dry weather flow regime. Based on these experimental data, Vesilind Model was used to characterize the settling behavior in the anaerobic and primary facultative ponds. Whereas Standard Methods for the examination of water and wastewater were used to determine the total suspended solids (TSS) concentrations in the ponds, batch column settling tests were used to generate the batch settling curves for each pond. Generally, good settling behavior characterized by SVI values of less than 150 mL/g was observed during the study period. Highest settling velocities of 1.16 m/hr and 1.22 m/hr were recorded in the anaerobic and primary facultative ponds respectively for TSS concentrations of 0.6 g/L and 0.416 g/L. Optimal maximum velocity (Vmax) values of 3.42 m/hr and 1.78 m/hr were observed in the anaerobic and primary facultative ponds respectively. The corresponding optimal model parameters (n) describing the measured data accurately were 0.47 L/g and 0.51 L/g respectively. The model parameters so obtained may be useful in characterizing the sedimentation behavior in the WSP during the dry weather flow regimes.Abstract: Waste Stabilization Ponds (WSP) provide both cost-effective and high-performance wastewater treatment benefits in the tropical regions. The 3-month sludge settling behavior in the Kibendera WSP in Ruiru, Kenya, was studied between July and September 2022. The study aimed at determining the sludge volume index (SVI) and hindered settling velocity du...Show More