Development of Electrically Powered Reciprocating Cocoa Pods Breaking Machine

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International Journal of Excellence Innovation and Development ||Volume 2, Issue 1, Jan. 2019||Page No. 016-020||

Development of Electrically Powered Reciprocating Cocoa Pods Breaking Machine O.O Caleb 1, B.O Akinnuli 2 1 Department of Mechanical Engineering, Federal University of Technology, Akure, Nigeria Department of Industrial and Production Engineering, Federal University of Technology, Akure, Nigeria

2

Abstracts––Cocoa (Theobroma cacao) is one of the main cash crops exported from Nigeria to other countries. The removal of the beans from the cocoa pods has been done manually for a very long time which reduces the efficiency of the process and sometimes results in loss of an amount of the beans. This work considers the design, fabrication and cost of a simple reciprocating electrically powered cocoa pod breaking machine to facilitate the removal of cocoa beans from the pods. Electric motor of 1 hp power rate and 1400 rpm was installed. After evaluation of the machine, the seed damage percentage was found to be 0 %. This shows 100 % effectiveness while the efficiency of the machine was 93 %.The belt speed of 6.6 m/s was used with designed hammer weight of 150 N and the breaking rate per hour ranges from 3600-7600 pods depending on the size of the pods. The machine production cost was fifty-six thousand eight hundred Naira (N56,800) only equivalent of US$ 2,272 at exchange rate of N 250 per Dollar as at the time of this research. Keywords––Cocoa pods, design, estimation, reciprocating machine

fabrication,

Plate 1: Transverse Section of Cocoa Fruit (Source: Adzimah and Asiam, 2010)

cost

INTRODUCTION Cocoa is one of the cash crops of great significance grown in the world. In Nigeria, Cocoa is a prominent perennial cash crop planted in the south western part of Nigeria. Cocoa production has been a supporting factor for the economy of producing countries because of its high export earnings. The cocoa seed usually referred to as cocoa beans is exported to the western world for processing where several products are manufactured and imported back to Nigeriaand other developing countries at a relatively high cost (Adewumi, 1997). Cocoa is key import goods for consuming countries due to its various uses and its economic value. The cocoa fruit is made up of the pod, beans, husk, placenta and mucilaginous pulp which has a sweet juice called ‘sweating’ (Adzimah and Asiam, 2010). The cocoa pod is a berry which varies in size, shape and colour. The fully grown and ripe cocoa pod is about 15.24 cm to 32 cm in length, 7.62 cm to 10.16 cm in diameter at the centre (Adzimah and Asiam, 2010 and Ramji et. al., 2018). The pod takes about 5 - 6 months to ripen and Figure 1 and Plate 1 show the transverse section while Figure 2 shows longitudinal section of a whole cocoa fruit. The husk has an appreciable thickness. A pod contains between 30 and 40 beans usually with each bean surrounded by mucilaginous pulp (Adzimahans Asiam, 2010; and Ramji et. al., 2018). www.ijeid.com

Fig. 1: Transverse Cross Section of a Matured Cocoa Pod.

Fig. 2: Longitudinal section of a whole cocoa pod.

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Development of electrically powered reciprocating cocoa pods breaking machine The principal use and economic importance of cocoa are in medicine, production of chocolate, oil, petrol, candles, lightning oil, ointments, and soaps (Opeke, 1987). Cocoa butter, made from the fat extracted from the beans, is a stable fat used in the production of cosmetics and pharmaceutical products. The beans are milled into powder for making beverages, chocolates, ice cream, soft drinks, cakes, biscuits, flavouring agents and other confectionaries (Ramji, et.al, 2018). Syamsiro et. al. (2012) revealed that cocoa husk is a promising biomass for renewable energy production which can replace fossil fuel and reduce CO2 emissions. The productivity of the cocoa farm can be increased by simplifying the bean removing process (Arivu et. al, 2018). Cocoa beans processing for human consumption is growing into different products from time to time (Akinnuliet.al,2015).The processing of cocoa for production of cocoa butter, beverage and cake includes the breaking of the pods; extraction, fermentation, drying, dehulling and winnowing of the beans, (Ademosun, 1993; Adewumi, 1997; Faborode and Oladosun, 1991). The breaking of pods is a size reduction process, whose aim is to extract the beans from the pod. According to Audu et al.,( 2004); Vejesit and Salohkhe, (2004), and Adewumi et al., (2006) compressive, impact or shearing forces are the forces involved in breaking of cocoa pods depending on the type of machine and process used. When done manually, a lot of seeds are damaged in the process when cutlass/machete is used in the splitting of the cocoa pods, reducing the quantity of beans suitable for fermentation. The process is time consuming, dependent on the strength of the manpower, and prone to accidents (Bamgboye, 2003). Fonsso et al.,(2016) observed that a major problem facing cocoa farmers during breaking process is Cocoa seeds damage. Over the years, efforts have been put in place to simplify the procedures of processing cocoa through mechanical means. Jabagun (1965) reported that the first cocoa pod breaker in Nigeria was constructed and tested at the Cocoa Research Institute of Nigeria (CRIN).This machine required at least two operators in which one will be feeding the cocoa pods and the other one will collect the beans. Ademosun (1990) designed a medium-scale

Caleb and Akinnuli

cocoa dehulling and winnowing machine. From the performance evaluated, the machine is easy to operate with only the adjustment of roller clearance. The machine was found to have high dehulling and winnowing efficiencies at the optimum roller clearance. Faborode and Oladosun (1991) developed a machine to break cocoa pods and extract wet beans. The machine consists of a hopper, meter plate, hammer and a reciprocating sieve. The pods were broken by the hammer. The husk was separated by the vibrating sieve. The beans were then collected through the discharge chute. In 2010, Adzimah and Asiam designed a cocoa pod splitting machine which was manufactured from locally available scrap materials. It was assembled and maintained at a relatively low cost. The knives were actuated by simple hydraulic mechanisms devoid any major stresses, forces or moments acting on them. These mechanisms were powered by hydrostatic hydraulic pumps of power rating of 87.5 kW (65.625 hp). The machine can be assembled and/or disassembled easily and quickly, and, therefore can be owned by a group of cocoa farmers who can easily bear the cost. The problems identified from the existing technology are to: reduce the human effort, improve the production, and make working process simple and easily controlled by farmers. The aim of this work is to design a cocoa pod breaking machine. The objectives are to design a simple electrically powered reciprocating cocoa pod breaking machine and to carry out the cost estimation of the design of the machine towards its development.

METHODOLOGY The aim of breaking cocoa pod is to extract cocoa beans from placenta. The machine was designed and fabricated using locally available materials. Thorough design analysis was done. The size of the cocoa pods in terms of length and diameter were found to range from 160 mm to 234 mm and 88 mm to 118 mm respectively. The dimension of hopper outlet and the clearance between the hammer and the breaking surface is determined by the size of the cocoa pod. Physical properties of wet cocoa pods are shown in Table 1 and the properties of wet cocoa beans are shown in Table 2.

Table 1: Physical properties of whole cocoa pods (± standard error). S/N Physical properties Variety amelonado criollo trinitario 1 Angle of repose (o) 15.5 ± 1.0 16.1 ± 1.4 20.1 ± 1.3 2 Bulk density (kg/m3) 389.9 ± 8.9 464.5± 7.8 470.3 ± 8.0 3 Volume (cm3) 397.3 ±22.7 710.5 ± 57/2 599.5 ± 44.0 4 Coefficient of friction On wood 0.38 ±0.01 0.25 ± 0.02 0.25 ± 0.03 On galvanised steel 0.32 ± 0.02 0.25 ± 0.02 0.25 ± 0.03 5 Number of wet beans per pod 38 ±1 38 ±2 36 ± 2 6 Gravimetric composition Pod husk (%) 68.6 ± 0/84 78.3 ± 1.0 76.5 ± 1.2 Wet beans (%) 28.5 ±0.76 18.7 ± 0.8 20.2 ±1.2 www.ijeid.com

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International Journal of Excellence Innovation and Development ||Volume 2, Issue 1, Jan. 2019||Page No. 016-020|| Table 2: Physical properties of wet beans. Sr. No. Physical properties Variety amelonado criollo trinitario o 1 Angle of repose ( ) 52.3 ± 1.4 48.6 ± 2.4 51.4 ±2.9 2 Coefficient of friction On wood On galvanised steel

Sr. No. 1 2 3 4 5 6 7

0.39 ± 0.03 0.48 ± 0.06 0.57 ± 0.07 0.24 ± 0.01 0.44 ±0.06 0.55 ±0.01

Table 3: Material selection and criteria for selection. Criteria for selection Material selected Resistance to wear Wood Rigidity and stability Angle iron Resistance to torsional Mild steel stress Hopper and outlet collector Durability and rigidity Mild steel Hammer High density Mild steel Breaking surface Strength Angle iron Belt Tension and strength V- belt Component Pulley Frame Shaft

The angle of repose of cocoa pods, husks and beans were determined. For a solid material to flows down an inclined surface freely, the angle of inclination of the surface to the horizontal must at least be equal to the dynamic angle of repose of the material (Maduako and Faborode, 1990).

Reason for selection Readily available Rigidity Great machinability and Readily available Readily available Readily available durability

Maintenance of the Machine Since usage of this machine is seasonal and only used when there is ripe cocoa, it should be water washed after use. The surfaces that made contact with cocoa should be covered with film of oil. This will prevent corrosion and increases the life span of the machine.

Summary of Component Design The resistance force of the cocoa pod was also determined for the appropriate selection of weight of hammer that will not cause damage to the cocoa beans. The weight of the hammer was determined to be 150 N. Electric motor of 1hp was selected. V-belt “A” type was selected based on the type of electric motor. Diameter of the small pulley on the motor was found to be 90 mm while that of the big pulley was determined to be 270 mm with a centre distance of 270 mm between them. The V-belt rating is 1.39 kW for belt speed of 6.6 m/s and equivalent pitch diameter 102.6 mm and one belt is selected for the operation. The shaft of length 690 mm with diameter 25 mm carrying hammer is supported on two bearings. The designed machine is shown in Figure 3. Materials selected for various components of the machines are shown in Table 3. Principle of Machine Operations The hopper is fed manually with the cocoa pods to be broken. As the hopper is filled, the electric motor of the machine is energized. The hammer with its sheet plate moves vertically upward which allows the cocoa pods to be rolled in between the hammer and the fixed angle bars horizontally welded to the frame directly under the flat hammer. As the hammer is coming down, it compresses the cocoa pods against the horizontal angle bars this makes the pods broken into smaller pieces both the seeds and the broken pods falls by gravity into the collector. The process continues to repeat till all the pods were crushed and operation stopped. www.ijeid.com

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Sr. No. 1 2 3 4 5 6 7

Description Hopper Bearing V- belt – A –SO Shaft Pulley Frame Electric motor

Qty. 2 2 1 1 1

Material Metal sheet Rubber Mild steel Wood Angle iron

1

Fig. 3: Machine Designed.

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Development of electrically powered reciprocating cocoa pods breaking machine The machine was fabricated component by component according to the design specifications and materials selected on Table 3. Arc welding was used in fabrication of the frame, hopper, crushing surface and housing support. The components were assembled together and the machine was tested by an operator. The cost of production of the machine is presented on Table 4.

Sr. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Table 4: Bill of engineering measurement and evaluation. Components Specification Qty Unit Total and cost cost materials (N) (N) Hammer 460 mm by 1 3,200 3,200 460mm Angle iron 2 length 2 4,500 9,000 Bearing 1 2,200 2,200 pair Pulley 1 1,100 1,100 Hacksaw 1 500 500 blade Electrode Guage 12 1 3,500 3,500 pack Iron rod 1 ft 3 1,500 4,500 Metal plate 2.5 mm thick 1 7,500 7,500 sheet Paint and 1 2,000 2,000 brush litre Belt A 80 1 1,300 1,300 Cutting disc 1 1,000 1,000 Grinding disc 1 1,200 1,200 Electric motor 1 hp 1 10,300 10,300 Workmanship 5,000 Miscellaneous 4,000 Total 56,800

RESULTS AND DISCUSSIONS The machine developed has a total mass of 45 kg; the hammer was designed to be 150 N by weight, while the electric motor was 1 hp of power rating. The small and big pullies were of 90 mm and 270 mm diameter with their centre distance of 270 mm. the driving belt of type “A” was designed to have a power rating of 1.39 kW, speed of 6.6 m/s and equivalent pitch diameter of 102.6 mm. the driving shaft is of 690 mm in length and 25 mm diameter. Concerning the machine performance evaluation, 500 cocoa pods were crushed at 100 pods per batch that gave an average efficiency of 93 %, 0 % of damage which proved the machine to be 100 % effective, while the production cost is N 56,000.

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[2]

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CONCLUSION AND RECOMMENDATIONS The machine for breaking cocoa pods was designed and fabricated based on reciprocating motion principle. One operator is needed for the efficient use of the machine. The machine was found to be more efficient in breaking cocoa pods at preliminary processing level before fermentation for sun drying. This has reduced drudgery, and injury sustained by farmers when cutlass is used as means of breaking cocoa pods. www.ijeid.com

Caleb and Akinnuli

[13]

Ademosun, O. C. 1990.Performance Evaluation of a Medium-scale Cocoa Dehulling and Winnowing Machine. Agriculture Mechanization in Asia, Africa and Latin America. 21(2): 57-64. Ademosun, O.C. 1993.Performance evaluation of a medium scale dehulling and winnowing machine. Agricultural Mechanization in Asia, Africa and Latin America. 24(2): 57-60. Adewumi, B. A. 1997.Cocoa bean processing and drying equipment for small and medium scale industries. A paper presented at a conference titled ‘The Role of Science and technology in the Development of Small/Medium Scale Industries in Nigeria’ organized by the Centre for Research and Development, Ondo State University, Ado-Ekiti. 17pp. Adewumi, B. and Fatusin,A. 2006. “Design, Fabrication and Testing of an Impact-Type Hand Operated Cocoa Pod Breaker” Agricultural Engineering International: the CIGR ejournal. Manuscript PM 06 022 Vol. VIII. Adewumi, B. A, Ademosun, O. C. and Ogunlowo, A. S. 2006. Design, fabrication and preliminary testing of a thresher-cleaner for legume. Journal of Food Science and Technology, India 44(3). Adzimah, S. K. and Asiam, E. K. 2010.Design of a Cocoa Pod Splitting Machine. Research Journal of Applied Sciences, Engineering and Technology 2(7): 622-634. Akinnuli, B.O.; Bekunmi, O.S.; and Osueke, C.O. 2010. “Design Concepts towards Cocoa Winnowing Mechanization for Nibs Production” in Manufacturing Industries International Research Journal of Engineering and Technology, Vol 3, Dec 16. Arivu, Y., Manikandan S., Sivakarthi T., Gowtham M. M. 2018. Design and Fabrication of Cocoa Pod Splitting and Bean Extraction Machine. International Research Journal of Engineering and Technology (IRJET).Vol. 5.www.irjet.net Audu, I.; Oloso, A. O.; and Umar, B. 2004. “Development of a concentric cylinder locust dehullerˮ CIGR-Ejournal, PM 04 003 Vol. 6. Bamgboye, A. I. 2003. Effect of some physical properties of cocoa bean on post harvest delay on its compressive and impact rupture. Discovery and Innovations 15(3): 137-141. Faborode, M. O. and Oladosun, G. A. 1991.Development of a cocoa pod processing machine. The Nigerian Engineers. 26(4): 26-31. Fonsso, J. D., Nzié1, W., Ntamack, G. E., and Kenmeugné, B. 2016.Hertz Theory Application in Modeling and Analysis of Mechanical Rupture Force of Cocoa Pod. International Journal of Mechanical Engineering and Applications 2016; 4(5): 182-188. http://www.sciencepublishinggroup.com/j/ijmea Jabagun, J. A. 1965.A mechanised cocoa pod sheller. The Nigeria Aquaculture Journal 2(1): 4445.

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International Journal of Excellence Innovation and Development ||Volume 2, Issue 1, Jan. 2019||Page No. 016-020|| [14] Maduako, J. N. and Faborode, M. O. 1990.Some Physical Properties of Cocoa Pods in Relation to Primary Processing. Ife Journal of Technology 2 (1): 4-5 [15] Opeke, L. K. 1987.Tropical Tree Crops. John and Sons, Clichester, Pg 108 – 119. [16] Ramji, K. S. H.; Kumar, P. S; Yogeshkumar, T. and Bharathkumar, M. 2018.Design and Development of Semi-Automatic Cocoa Pod Splitting Machine. International Journal for Scientific Research & Development. Vol. 6 (01), 2321-0613. [17] Syamsiro, M; Saptoadi, H; Tambunan, B. H. and Pambudi, N. A. 2012.A Preliminary Study on Use of Cocoa Pod Husk as a Renewable Source of Energy in Indonesia. Energy for Sustainable Development 16:74-77.

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[18] Vejesit, A. and Salokhe, V. 2004. “Studies on machine-crop parameters of an axial flow thresher for threshing soy bean”. CIGRE journal Vol. 6.

Biography of Author(s) O. O. Caleb (B. Eng. Mechanical Engineering, M. Eng. Building Services Engineering) is a lecturer at the Department of Mechanical Engineering Federal University of Technology Akure, Ondo State, Nigeria B.O Akinnuli (B. Eng. Mechanical Engineering, M. Eng. and Ph. D in Industrial and Production Engineering,) is associate Professor at the Department of Industrial and Production Engineering, Federal University of Technology, Akure, Ondo State, Nigeria.

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