6 research outputs found
COCONUT HUSK CHAR BIOSORPTIVITY IN HEAVY METAL DIMINUTION FROM CONTAMINATED SURFACE WATER
Applicability of coconut husk char in heavy metal removal was examined in the study. The surface morphology and elemental compositions of the char was investigated with SEM-EDX machine. Heavy metals sorption on 100 g of the char dosage was studied under five different contact times in the column experiment. Isotherm and kinetic models were the probing tools for biosorption mechanism prediction. Results indicated removal efficiency for chromium, cobalt, cadmium, aluminum and arsenic at 60 mins contact time were 72, 80, 86, 89 and 100 % respectively. Contaminate removal depends on metal involved and sorption contact time. Adsorption data are fitted well into Freundlich isotherm model (R2 > 0.92). Pseudo kinetic second order well described the adsorption process, with most R2 values ≥ 0.94. Coconut husk char is an effective biosorbent in sequestration of arsenic, cadmium, aluminum and cobalt in contaminated surface water
COCONUT HUSK CHAR BIOSORPTIVITY IN HEAVY METAL DIMINUTION FROM CONTAMINATED SURFACE WATER
Applicability of coconut husk char in heavy metal removal was examined in the study. The surface morphology and elemental compositions of the char was investigated with SEM-EDX machine. Heavy metals sorption on 100 g of the char dosage was studied under five different contact times in the column experiment. Isotherm and kinetic models were the probing tools for biosorption mechanism prediction. Results indicated removal efficiency for chromium, cobalt, cadmium, aluminum and arsenic at 60 mins contact time were 72, 80, 86, 89 and 100 % respectively. Contaminate removal depends on metal involved and sorption contact time. Adsorption data are fitted well into Freundlich isotherm model (R2 > 0.92). Pseudo kinetic second order well described the adsorption process, with most R2 values ≥ 0.94. Coconut husk char is an effective biosorbent in sequestration of arsenic, cadmium, aluminum and cobalt in contaminated surface water
Effect of Double-T and V-shaped Pipe Configurations and Perforations on the Quality of Chicken Litter Compost
Livestock waste management has received much attention because of the huge volume and instability. One of the good management practices adopted to address this menace is composting. This study examined the effect of specialized passively aerated composters on some physicochemical properties of chicken litter. The composter is made up of six double T and V shaped pipe with three different perforation diameters of 15, 20 and 25 mm. Pile configuration of the developed composters had marked effect on total nitrogen content (p0.05) of the compost subjected to 90 days composting time. The composters had uniform air distribution as pile temperature was not significantly affected by pile configuration, perforation size, and their interactions. Furthermore, both T and V shaped pipe structures reached a thermophilic temperature of 49.0 and 67 oC respectively and the compost stabilized in the 12th week. From the agronomic point of view, V-shaped pipe outperformed double inverted T pipes with perforation sizes of 15 and 20 mm. Overall result from this study suggests that double-T and V-shaped composters are feasible composting systems that can enhance biodegradation, maturation, and stability of chicken litter.Keyword: compost, litter, composter, double-T, pile, perforation
Optimization of Methane Yield in Solid-State Anaerobic Co-Digestion of Dairy Manure and Corn Stover
Sole dependence on fossil fuel and the concomitant environmental concerns could be minimized through the optimization of green energy generation from the growing volume of onfarm organic wastes. In this mesophilic study, green energy, mainly methane, was optimized through the solid-state anerobic co-digestion (SSAD) of two on-farm organic wastes (dairy manure with corn stover). Factors considered to achieve the improved methane yield under a total solids of 16% were particle size of corn stover (0.18 – 0.42 and 0.42 – 0.84 mm), alkaline pretreatment type (thermo-chemical and wet state), alkaline-pretreatment reagent (NaOH, NH4OH, and Ca(OH)2) used for the corn stover, and the magnetite nanoparticles(20, 50, and 75 mg/L) thereafter added to the treatment with highest methane yield. Kinetic models were used to describe some of the high methane yield as well as the environmental impact investigated with life cycle assessment. Results indicated that corn stover with particle size 0.42 - 0.84 mm blended with dairy manure under a C/N of 24 had the highest methane yield (106 L/ kgVS) under 60 days retention time. After pretreatment of the 0.42 - 0.84 mm corn stover with the three different alkaline reagents, methane yield improved under this wet state pretreatment relative to thermochemical. For instance, calcium pretreated corn stover blended with dairy manure (CaW) had the highest methane yield (176 L / kgVS) under a reduced retention time (79 days), overcame potential volatile fatty acids accumulation and digester upset relative to other pretreated treatments. Furthermore, addition of 20 mg of the nanoparticles to the CaW treatment further enhanced methane yield (191 L / kg VS), minimized digester upset, and reduced retention time to 52 days. Suitable process parameters for methanogenic activities were 0.1 - 0.5 for VFA/Ammonia and VFA/Alkalinity ratios. Free ammonia concentration between 258 – 347 mg/L does not affect methanogenic activities. Environmnetal impact aseessment indicated that pretreatment negatively influenced human health factors and eutrophication potentials though reduced ozone depletion, global warming potential, and smog potentials. The solid-state of dairy manure co-digested with corn stover has the potential to improve green energy generation that could complement fossil fuel and address waste management challenges
Deleterious Emission Abatement through Structured Energy Use Pattern: A North Central Nigeria Perspective
Holistic view of household energy consumption based on greenhouse gas emissions in the North Central cities of Nigeria was examined in this study. Scenarios considered were based on income level of energy users (low and high) and energy metering system (i.e. pre-paid and post-paid energy billing systems). Strong direct nexus was observed between energy use and emissions pattern. Energy utilization by post-paid category had higher weekly average value of 35.09 and 41.70 kWh as against 23.18 and 33.38 kWh for low and high income pre-paid consumers respectively. Energy use and greenhouse gas emissions from both classification followed similar trend. Data obtained and analysed in the study show that global warming and acidification potentials could be reduced by 33.94 and 19.95 % for low and high income category consumers when pre-paid meters are in place. Conclusively, energy system users with pre-paid metering system displayed reasonable level of management decisions that reduce energy wastage and consequently environmental negative impacts
Investigation of Energy Use Pattern and Emission Discharge in Nigeria: A Case Study of South West Zone
Electricity demand has increased with population growth, industrialization and civilization. Most householders
are barely conscious of the conservative measures for available limited supply, while the environmental impact has
rarely been taken into cognizance by consumers. The study examines end-users attitude to energy consumption in
Nigeria based on four scenarios. Gaseous emissions data obtained from prepaid and post-paid metering systems usage
in low-income and high-income housing types were analyzed. Results obtained indicate strong relationship between
energy use and emissions with significantly different emission generation. About 38% and 23% reduction in global
warming and acidification potential is achieved by a switch to prepaid meters for both income earners. Post-paid
low-income earners utilized the highest energy (59.8kW/hr) while the prepaid high-income earners had the minimum
(31.1kW/hr). Energy use and greenhouse gas emissions from both earners followed similar trend. Prepaid metering
system usage improves energy consumption, thereby offsetting global warming and acidification impacts