Figure 3 - available via license: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
Content may be subject to copyright.
Bulk Densities of the CPH/KPH Samples Presented in Table 2 are the values obtained from the proximate and the ultimate analyses of the two waste materials. The MMC is 10.96% in Sample A and this is the lowest, while its highest value was from Sample K with 13.21%. There was an increase in the MMC of the blends, ranging from 11.19% to 12.99%, as the mass proportion of KPH in the blends increased. This same trend was exhibited by the samples as regards VMC, with the lowest and the highest values being 62.89% and 65.92% respectively, while the blends similarly have their VMC values ranging from 63.19% to 65.62%. The results obtained for FAC and FCC showed Sample A as having the highest values, 13.42% and 12.73% respectively, while lowest values were recorded from Sample K as 10.63% and 10.24% respectively. In the case of the blends, the values of the two contents reduced with increase in the mass proportion of KPH, ranging 13.14% -10.91% and 12.48% -10.49% respectively.
Source publication
Huge quantities of harvest wastes that are generated from agricultural practices at every farming season in Nigeria are not put into significant use. As an attempt towards adopting these abundant by-products as bioenergy resources for electricity generation, yearly quantities of both cocoa and kolanut harvest residues were estimated in this study....
Context in source publication
Context 1
... bulk densities of the samples are as described by figure 3, which shows pure CPH (Sample A) as having the highest value, 712.6 kg/m 3 , while the least is Sample K (pure KPH) with 703.8 kg/m 3 . The blends have their bulk densities proportional to the percentage weight of KPH in the samples. ...
Citations
... The processing of kola nut generates huge wastes in the form of pod and seed shell (testa). It has been estimated that an average of 90,000 metric tons of kola nut wastes is generated annually in Nigeria (Ajewole et al., 2021). Kola nut fruit consists (%wt) of the pod (47.79), seed (38.66) and seed shell (13.55) as reported by Ebana et al. (2015). ...
... The 10% bioethanol-fuel mix was investigated for energy generation and produced 13.1 Nm torque and 2953 W power compared to 12.4 Nm and 2574 W produced with gasoline. It had been estimated that Nigeria can generate 29,000 MW of energy from combination of cocoa pod and kola nut (50:50) that are abundant in the country (Ajewole et al., 2021). It is evident from the foregoing that kola nut residues can serve as veritable sources of novel materials such as dyes and biocatalysts and clean renewable energy. ...
Kola nut tree (Cola nitida) is cash and perennial crop that is cultivated for the production of its seed called kola nut which is widely consumed as stimulant and used in traditional ceremonies in West Africa. Its cultivation has spread from Africa to Asia, South America and the Caribbean. Processing of the fruits to obtain the seeds leads to generation of some agrowastes; notably the pod and seed shell which are dumped on the farmland and in the market places. Though, kola nut has been explored for some industrial applications in the production of dyes, drinks and stimulants; its utilities have not been fully tapped. The pod, seed and seed shell contain a lot of phytochemicals that can serve as precursors to develop varieties of drugs among other potentials. Traditionally, the plant is an important component of ethnomedicine in West Africa to treat different ailments. In recent times, its parts, particularly pod, seed and seed shell have been valorized for high-end services such as in catalytic production of biofuel, development of low-cost adsorbents, production of enzymes, organic fertilizers and animal feeds as well as in the green synthesis of different nanoparticles for diverse applications. In the spirit of promotion of circular bioeconomy, this review x-rays contributions of Cola nitida to developments in catalysis, biotechnology and nanotechnology with the view of extending its frontiers of utilization for sustainable development. The report is the first of such review that presents C. nitida beyond its basic biology, phytochemistry and cultivation.
... Many studies have been conducted on utilization of biomass for energy production in Nigeria -CBE ( Igbokwe et al., 2022 ); biomass residues and their bioenergy potential ( Ezealigo et al., 2021 ); agrobioenergy potential to reduce emissions and mitigate climate change ( Elum et al., 2017 ); different crops potential for energy valorization ( Jekayinfa et al., 2020 ); oil palm ( Anyaoha and Zhang, 2021 ), maize cob ( Otitolaiye et al., 2021 ), different residues from corn ( Mohammed et al., 2020 ), cocoa and kolanut residues ( Ajewole et al., 2021 ), carica papaya ( Jensen et al., 2020 ), blending of oil palm and MSW ( Salman et al., 2019 ), bioethanol production from lignocellulosic biomass feedstock ( Awoyale and Lokhat, 2019 ). Calorific value of characterized MSW ( Nwoke et al., 2020 ), Energy production from MSW ( Ibikunle et al., 2019( Ibikunle et al., , 2021, economic feasibility of WtE plant ( Chukwuma et al., 2021a ), economic and environmental implications of energy recovery from MSW , optimization of methane emissions for bioelectricity production ( Suberu et al., 2013 ). ...
... It is articulated that as 2nd generation technologies (for lignocellulosic feedstock) develops and becomes more commercially viable, negative effect of land and resource competition on food security will reduce ( Matemilola et al., 2019 ). Thus, many studies in Nigeria are beginning to focus on 2nd generation biofuels ( Ezealigo et al., 2021 ) which includes lignocellulosic biomass ( Ajewole et al., 2021 ) and 3rd generation biofuel ( Shiru and Shiru, 2021 ). 2nd and 3rd G biofuels ( Shiru and Shiru, 2021 ) has some important barriers that needs to be surmounted to make it commercially viable ( Suberu et al., 2013 ). ...
... Other studies estimated energy potential from agro-residues. The estimated 681,000 t of cocoa wastes and 90,000 t of kolanut residues produced annually in Nigeria is calculated to generate 29,000 MW of electricity ( Ajewole et al., 2021 ). ...
Affordable and clean energy is critical to achieving the UN SDGs . Fossils accounts for the major source of energy in Nigeria. Their combustion lead to GHG emissions and climate change. The country also has a very poor energy system. Accordingly, the emphasis on transition to renewable energy. This study carried out a systematic review to identify how biomass energy recovery has progressed; and the major themes driving the field in Nigeria. The challenges facing utilization of biomass for energy production were also identified. Using relevant Boolean-operator keywords, search was conducted on SCOPUS and Google Scholar databases. Established inclusion and exclusion criteria were used in selecting suitable literature. The result shows research on biomass energy recovery has increased greatly since 2012. Climate change and environmental concerns, energy diversification, energy access, waste management, municipal solid waste, agricultural residues and policies are the themes driving biomass valorization for energy recovery in Nigeria. The challenges facing adoption of biofuels in Nigeria include poor waste management; resource considerations, lack of comparative economic and market advantages, technology and technical limitations and inconsistent policies. The MSW generated by the urban population of Nigeria is estimated to grow from 20.5 million tons (Mt) to 34.5 Mt from 2020 to 2040. More than 50% of the MSW are organics which are suitable for energy valorization. energy potential from crop residues based on annual crop production ranged from 1.28 TJ (for coconut shells) to 305 TJ for sorghum stalk. Some of the most studied thirteen crop residues are those of cassava, maize, sorghum, oil palm tree and others. Energy potential from crop residues based on crop production ranged from 1.28 TJ for coconut shells to 305 TJ for sorghum stalk. Effort should be on developing Nigeria agriculture and waste management system. The issue of fuel subsidies should also be addressed so as to create competitive business environment that will make renewable energy ventures attractive.
... It is important to know waste yields or rates generated per production unit to quantify or estimate the potential use of residual biomass. Ajewole et al. [46] report that, from a metric ton of recently harvested cocoa pods, 240 kg of dry beans and 506 kg of shells or dry pods are obtained. Which would represent a 24% product yield per ton and around 50% waste per ton. ...
The energy growing demand and the international environmental policies contribute to the use of renewable energy sources. Among these sources, biogas has acquired great relevance due to its energetic similarity to fuels such as liquefied petroleum gas (LPG) and natural gas (NG). However, biogas needs to be upgraded by removing CO2 and trace gases to obtain biomethane (>85% CH4). This review identifies and classifies seven techniques used in biogas upgrading, reported in academic and scientific publications. A 13-year review period (2008-2021) was considered. Lineal regression was used to analyze the publications number per year. Membranes use represents the largest proportion of publications (33%), while activated carbon (AC) reaches only 22%. However, the use and application of AC obtained the best trend as a publication topic, with a maximum value of R2 = 0.7882. This review documents publish works on obtaining and applying AC in biogas enrichment processes. It includes a review of the characteristics and generation rates of various residual lignocellulosic materials used in the synthesis of AC, the synthesis processes, the characterization techniques, and the final adsorption capacities.
... In [42], the authors submitted that agricultural wastes in Nigeria have energy potential of approximately 1.09 EJ, majorly from maize, cassava, oil palm, rice, plantain, and sorghum; while animal wastes, municipal solid waste, and forest residues have energy potentials of 0.65, 0.11, and 0.05 EJ, respectively. While [45] presented thermo-electric potentials of lumbering residues of three different woods that are local to Nigeria, energy densification and thermo-property characterization of eleven different blends of two agro-harvest wastes from same locality was studied in [46]. ...
... Approximately 601,000 and 90,000 metric tons respectively, of cocoa and kolanut harvest residues are produced annually in Nigeria [46]. This makes the two waste materials to be very significant agricultural by-products in the country in terms of quantity, availability and accessibility. ...
... As blending of biomass residues offers conversion advantages of their energies, electricity generation from a carefully selected blend of cocoa residue (CR) and kolanut residue (KR) was therefore, the focus of this present study, as a continuation to the earlier research reported in [46]. The preceding study thermally characterized eleven different blends of the two farming harvest residues, composed in the proportions shown in Table 1. ...
As a way of wastes-to-voltage conversion, experimental benchtest trial of electricity generation from a blend of cocoa and kolanut harvest by-products is presented in this study. Bioethanol obtained from the blend, through a process of alcoholic fermentation, was mixed with gasoline at specific proportion and employed to fire a spark ignition engine that served as a prime-mover in driving a four-pole three-phase salient-pole synchronous machine. Performance of the driving machine, as the fuel-mix proportion and its speed of rotation varied, was studied. Likewise the electric power output characteristic of the driven machine, when operated at its rated synchronous speed, was examined. It was found that the driving machine performed better on mixed fuel than pure gasoline. There were gradual increases in the torque and the power developed by the machine as the proportion of ethanol in the fuel-mix and the rotational speed increased. While the highest values of torque and power developed on using pure gasoline were 12.4 Nm and 2574 W respectively at 1900 rpm, 13.1 Nm torque and 2953 W power were obtained from the machine when ignited with 10%-bioethanol fuel-mix at the same speed. Also, with 90 Vdc excitation voltage and rotation at 1500 rpm synchronous speed, the driven machine continuously generated electricity at 207.6 Vrms (line-to-line), 1.169 A, 0.698 power factor, 48.17 Hz, 0.294 kW output. This study demonstrated the possibility of continuous generation of electric power from cocoa and kolanut wastes. Result obtained from the laboratory-based trial indicates that at such agricultural regions that are advantaged in the production of the two crops, harvest residues of the crops can be explored as steady source of biofuel for off-grid microgrid electrification.
... In [42], the authors submitted that agricultural wastes in Nigeria have energy potential of approximately 1.09 EJ, majorly from maize, cassava, oil palm, rice, plantain, and sorghum; while animal wastes, municipal solid waste, and forest residues have energy potentials of 0.65, 0.11, and 0.05 EJ, respectively. While [45] presented thermo-electric potentials of lumbering residues of three different woods that are local to Nigeria, energy densification and thermo-property characterization of eleven different blends of two agro-harvest wastes from same locality was studied in [46]. ...
... Approximately 601,000 and 90,000 metric tons respectively, of cocoa and kolanut harvest residues are produced annually in Nigeria [46]. This makes the two waste materials to be very significant agricultural by-products in the country in terms of quantity, availability and accessibility. ...
... As blending of biomass residues offers conversion advantages of their energies, electricity generation from a carefully selected blend of cocoa residue (CR) and kolanut residue (KR) was therefore, the focus of this present study, as a continuation to the earlier research reported in [46]. The preceding study thermally characterized eleven different blends of the two farming harvest residues, composed in the proportions shown in Table 1. ...
