17 research outputs found
Development of a tractor-mounted kenaf harvesting machine
No full textThe potential of kenaf (Hibiscus cannabinus L.) as an industrial commercial crop has been exploited in recent times. Kenaf harvesting operations are manually done or use other machinery for sugarcane. This makes harvesting difficult, time consuming and high labour cost and demand. A survey of kenaf harvesting machinery revealed that sugar cane harvesters and other machinery were either modified or adopted to harvest kenaf, hence field equipment for harvesting whole kenaf stems continues to be of interest in kenaf production. This necessitated the need to develop an efficient kenaf harvesting machine. This study focused on the development of a tractor-mounted kenaf harvesting machine to harvest whole kenaf stems which is either broadcast or rowplanted. In this regard a study on the physical and cutting characteristics of kenaf stem varieties FH 952 and V 36 revealed that the maximum plant height recorded was 310 cm and the lowest was 150 cm. Maximum stem diameter was 30 mm and the smallest was 14 mm. The moisture contents determined ranged between 73-75% (wet basis) for V 36 at harvest and 60.3-62.3% (wet basis) for FH 952. The cutting characteristics of kenaf stems at three different moisture content levels of 35%, 55% and 72% were also studied. The results revealed that the maximum cutting force and shearing energy were 1584.55 N and 8.75 J, respectively for 35% moisture content, while 694.86 N and 3.50 J were recorded for 72% moisture content. The Young’s modulus ranged between 67.59 MPa to 234.24 MPa. Laboratory experiments were conducted on cutting kenaf stem of variety V36 using a rotary serrated cutting system. The effects of cutting speeds on the cutting torque and cutting power of varying kenaf stem diameters and at different moisture contents and four different cutting speeds, 400 rpm, 500 rpm, 600 rpm and 700 rpm were investigated. Based on the experiments, the cutting speed had significant effect on the cutting power and torque. The cutting speed was directly proportional to the specific cutting power, while the cutting torque was inversely proportional to the moisture content. Increasing the rotational speed from 400 rpm to 700 rpm reduced the cutting torque from 1.91 Nm to 1.49 Nm. The cutting torque was observed to be higher at lower moisture levels of less than 35%. As the moisture content increased to values greater than 35%, the torque decreased considerably. This indicates that an increase in moisture content reduces cutting torque as shown by the model coefficient of moisture content, ct = 1.771 − 0.02mc. This means more energy savings and high efficiency would be achieved at high cutting speeds as compared to impact cutting system at similar speeds. Regression equations capable of predicting cutting torque and cutting power at varying stem diameters and cutting speeds, in relation to kenaf stem moisture contents are presented. After the aforementioned studies, a kenaf harvesting machine incorporating a rotary serrated cutting system was developed and its performance evaluated based on the physical and cutting properties studied. The kenaf harvester is tractor-mounted and comprises of a hydraulic, cutting and gathering systems. The parameters evaluated were the harvesting field efficiency (FE), effective field capacity (EFC) and machine material capacity (MC). Kenaf varieties V36 and FH 952 were used for the experiments to determine the performance of the machine. Different tractor speeds ranging from 2.0 to 7.7 km hr-1 were used. Field test results of the machine harvesting kenaf varieties V36 and FH 952 gave a harvesting field efficiency of 61 – 76%, effective field capacity of 1.19 – 3.68 ha/day and machine material capacity of 91.8 – 283.66 tons/day. The optimal operating forward speed at 3.7 km hr-1 achieved an efficiency of 76%. Results of the field test showed that the tractor speed had a significant effect on the performance of the machine, in terms of its effective field capacity, field efficiency and the machine material capacity. The machine performance revealed a satisfactory performance of the cutting system and it is suitable for harvesting kenaf stems of varying sizes. Total operational cost of the developed kenaf harvesting machine of RM 322,870.40/annum was compared with the common manual harvesting method of RM 13,500,000/annum widely practiced in Malaysia, and also the 4-row impact cutting kenaf harvesting machine of RM 416,636.00. The analysis showed that about RM13,177,129.60/annum will be saved when compared with the manual method and a saving of RM 93,765.60/annum when compared with the 4-row impact cutting kenaf harvesting machine
Effect of cutting speed on cutting torque and cutting power of varying kenaf-stem diameters at different moisture contents
No full textThis study focused on the development of an efficient cutting system for kenaf harvesters. Laboratory experiments were conducted on cutting kenaf stems of variety V36 using a rotary serrated cutting system. The Torque Trak 10k data acquisition system was used for the experiment. The effect of cutting speed on cutting torque and cutting power of varying kenaf-stem diameters and at different moisture contents was investigated. Four different cutting speeds of 400 rpm, 500 rpm, 600 rpm and 700 rpm were used. The experiments showed that cutting speed had significant effect on cutting torque and cutting power requirements. The cutting speed was directly proportional to the specific cutting power, while the cutting torque was inversely proportional to the moisture content. Increasing the rotational speed from 400 rpm to 700 rpm reduced the cutting torque from 1.91 Nm to 1.49 Nm. The cutting torque was observed to be higher at lower moisture levels of less than 35%. As the moisture content was increased to values greater than 35%, the torque decreased considerably. This invariably indicated that an increase in moisture content reduced cutting torque as shown by the model coefficient of moisture content. Thus, more energy saving and hence, high efficiency, were achieved at high cutting speeds as compared to impact cutting system at similar speeds. Regression equations capable of predicting cutting torque and cutting power at varying stem diameters and cutting speeds, in relation to kenaf stem moisture contents, are presented
Physical and mechanical properties of kenaf stems at varying moisture contents
No full textPhysical and mechanical properties of kenaf stem Malaysian variety V 36 were studied. The physical properties revealed maximum plant height was 310 cm and the lowest was 150 cm. Maximum stem diameter was 30 mm and the smallest was 14 mm. The mechanical properties revealed the maximum cutting force and shearing energy were 1584.55 N and 8.75 J, respectively for 35% moisture content. While 694.86 N and 3.50 J were recorded for 72% moisture content. The Young's modulus ranged between 67.59 MPa to 234.24 MPa. The greater shearing energy was obtained at the lower levels in the stem
Some engineering properties of Palmyra palm tree (Borassus aethiopum) germinating shoot
No full textThis study was carried out to determine some engineering properties of germinating shoot of Palmyra Palm tree (Borassus aethiopum) relevant to the design of an agricultural harvesting machine. Seed volume, sphericity, weight, surface area, aspect ratio and compressive strength were determined at three different moisture contents of 41.72%, 26.11% and 18.39% (wb) respectively. Standard methods and instruments were used to conduct the experiments. The results of the physical properties revealed that the major, intermediate and minor diameters, surface area and weight increased with the increase in moisture content. The maximum mean values of the major, intermediate and minor diameters were 280.00 mm, 33.00 mm and 25.90 mm respectively while the minimum mean values were 209.67 mm, 16.67 mm and 15.21 mm at the three moisture contents respectively. The mean coefficient of variation for the major, intermediate and minor diameters were 10.57%, 32.84% and 10.59% respectively. The statistical analysis carried out on the physical properties shows that the F value (38.77) is greater than the F-critical value and also the P-value 1.74×1032is less than the significance level (α= 0.05) which means there is a significant difference between the physical properties of germinating shoot within the range of moisture contents. The mechanical properties of the Palmyra palm germinating shoot revealed a mean force at break as 1247.10 N, 650.00 N and 707.10 N for longitudinal, natural and transverse loading positions respectively. The stress at break has mean values of 1247.10 N/mm2, 650.00N/mm2 and 707.10 N/mm2 for longitudinal natural and transverse loading positions respectively. The energy at break has mean values of 2.16Nm, 2.42 Nm and 1.80Nm, for longitudinal natural and transverse loading positions respectively. The mean values of the energy at yield for longitudinal, natural and transverse loading positions were 1.56 Nm, 1.03 Nm and 1.44 Nm respectively. The stress at yield has mean values of 1158.50 N/mm2, 627.67 N/mm2 and 734.25 N/mm2 for longitudinal, natural and transverse loading positions respectively. While the mean values for the Young’s modulus at longitudinal, natural and transverse loading positions were 15326.00 N/mm2, 5768.80 N/mm2, and 5010.90 N/mm2 respectively
A comparative analysis of the performance of multiple meta-heuristic algorithms in sizing hybrid energy systems connected to an unreliable grid
No full textThe availability of affordable and reliable power supply fosters social and economic growth and raises the standard of living. In most developing nations, there is a considerable gap between energy supply and demand, often resulting in load shedding and blackouts. Integrating two or more renewable power sources is a potential solution for the inconsistent nature of renewable energy, thereby supplying clean and sustainable electricity. However, proper component sizing and operation planning for different system components are necessary for a reliable and cost-effective system. This paper compares the performance of three widely used optimisation techniques (Artificial Bee Colony (ABC), Genetic Algorithm (GA), and Particle Swarm Optimisation (PSO)) in determining the size of a hybrid renewable energy system (HRES) with the lowest levelised cost of energy (LCOE) to meet the energy needs of a dairy farm in a rural settlement. PSO is observed to be the best-performed algorithm proposing a system with an LCOE of $0.162 per kWh, a net present cost (NPC) of 2.05 million dollars and a payback period of 5 years and 7 months when compared with the existing power system. The proposed HRES is determined to reduce annual diesel usage by 96%. Therefore, significantly decreasing greenhouse gas (GHG) emissions. The PSO algorithm performs satisfactorily in terms of results and convergence time compared to the results from commercially available hybrid optimisation software (HOMER Pro)
Performance evaluation of a tractor mounted kenaf harvesting machine
No full textThe potential of kenaf (Hibiscus cannabinus L.) as an industrial commercial crop has been exploited in recent times. Recent findings from field studies have drawn
attention to the need to develop an efficient kenaf harvesting machine. Hence, field equipment for harvesting whole kenaf stems continues to be of interest in Kenaf
production. In this study, kenaf harvesting machine incorporating a rotary serrated cutting system was developed at Universiti Putra Malaysia. The kenaf harvester
which can harvest both row and broadcast planted kenaf is tractor mounted and comprises of hydraulic, cutting and the gathering systems. The parameters evaluated were the harvesting field efficiency (FE), effective field capacity (EFC) and machine material capacity (MC). Kenaf varieties V36 and FH 952 were used for the experiments to determine the performance of the machine. Different tractor speeds
ranging from 2.0 to 7.7 km hr-1 were used. The optimal operating forward speed at 3.7 km hr-1 achieved an efficiency of 76%. Results of the field test showed that the
tractor speed had a significant effect on the performance of the machine, in terms of its effective field capacity, field efficiency and the machine material capacity
Effects of tractor speeds on the performance of a kenaf harvesting machine
No full textKenaf (Hibiscus cannabinus L.) may next be an industrial crop based on research findings about its technical and commercial potentials. Field equipment for harvesting kenaf continues to be an important aspect of commercialization. Various studies have drawn attention to the need to develop an efficient kenaf harvesting machine. In this study, a rotary serrated cutting system kenaf harvesting machine developed at Universiti Putra Malaysia and kenaf varieties V36 and Fh 952 were used for the experiment. The effects of tractor speeds on the performance of the machine were investigated. Seven different tractor speeds, 2.0, 2.5, 3.7, 4.6, 5.8, 6.9, and 7.7km/hr were used based on the results of the experiments, the tractor speed had significant effect on the performance of the machine in terms of its effective field capacity and the machine capacity. The optimum operating forward speed that gave the highest efficiency of 76% was 3.7 km/h
Prevalence and Antibiotic susceptibility pattern of Salmonella isolates from milk products and water reservoirs in Maiduguri, North-Eastern Nigeria
No full textPRODUCTION OF COMPOSITE SOLID FUEL USING ORANGE PEELS AND CORN COBS FOR ENERGY SUPPLY
No full textAbstract: This study presents investigation of orange peels and corn cobs being some of the numerous biomass wastes in Nigeria to determine their characteristics through briquetting technology. This is part of the efforts geared towards production of fuel product from agro-waste biomass and a more environmentally friendly fuel that can be used as an alternative fuel to the commonly used fossil fuel that has brought about global warming threatening our environment and the earth. This effort is also to reduce our over-dependence on the use of fuel-wood so as to reduce its consequences on climate change and other consequences on the environment. In the process, orange peels and corn cobs were collected from within the environment of Chanchaga and Kasuwan-Gwari Local Government Area of Minna, Niger State, Nigeria. The materials were sun-dried and milled using locally fabricated harmer mill, sieved through a 2.36mm sieve and mixed in the ratio of 20:80, 80:20, and 50:50 – orange peels to corn cobs; labelled sample A, B and C respectively. The samples were mixed at varying weight with the paste of 80g of starch as the binder and compacted in a manually operated hydraulic jack briquetting machine. Their physical properties, proximate and ultimate analysis, ignition time, and water-boiling capacity of the produced briquettes were determined according to ASTM standard. Results from the produced briquette shows sample A with highest calorific value of 31886.041kcal/kg followed by sample B with 31295.618kcal/kg and the least was sample C with 31136.771kcal/kg respectively. Sample A also has the highest carbon content followed by sample B and C respectively. Meanwhile, sample B has the highest fixed carbon content followed by A and C respectively. The sulphur and nitrogen contents which are the toxic elements in fuel are 0.110% 0.345%, 0.280% and 2.024%, 2.086% and 2.009% for sample A, B and C respectively. This shows low toxic contents in the briquettes
Design, fabrication and testing of shea nut shelling machine
No full textSheanut (Butyrospernum paradoxum) is an oil rich tropical tree crop, which is indigenous to the West African savannah zone. In Nigeria, most of the sheanuts shelling are done manually by rural women and children, which is labour demanding and tedious. This research work was carried out to determine some physical and mechanical properties of sheanut in order to minimize economic losses associated with its processing. The mean values recorded for the physical properties at 25% moisture content (wb) are; major diameter (29.20 mm), intermediate diameter (21.90 mm), minor diameter (15.00 mm), geometric mean diameter (21.90 mm), arithmetic mean diameter (21.20 mm), angle of repose (30.280). The mean values for the mechanical properties are; linear limit force (0.80 kN), linear limit deformation (4.60 mm), bioyield point force (1.40 kN), bioyield point deformation (6.50 mm), rupture point force (2.10 kN) and rupture point deformation (9.60 mm). Based on the physical and mechanical properties, a sheanut shelling machine was developed that is capable of addressing the aforementioned problems. Putting into consideration better shelling and efficient separation of shea nuts so as to encourage more utilization and processing of shea nuts and its products. The machine was designed to be powered by 5 hp electric motor. It was tested to shell, separate and clean sheanuts. The result of the performance evaluation showed that the machine had shelling efficiency of 96%; cleaning efficiency of the machine was 69.56% while the recovery efficiency was 82.7%. The successful development of this machine will reduce drudgery and time taken associated with the traditional method of sheanut shelling and therefore will increase productivity and utilization
