Research, design and implementation of a coconut shell shredder and dehydrator machine for organic fertilizer production

MINISTRY OF EDUCATION AND TRAINING HCMC UNIVERSITY OF TECHNOLOGY AND EDUCATION FINAL REPORT STUDENT'S SCIENTIFIC RESEARCH TOPIC RESEARCH, DESIGN AND IMPLEMENTATION OF A COCONUT SHELL SHREDDER AND DEHYDRATOR MACHINE FOR ORGANIC FERTILIZER PRODUCTION S K C 0 9 TOPIC NUMBER: SV2022-200 PROJECT LEADER: CHU HUY HOANG SKC008102 Ho Chi Minh City, October 2022 MINISTRY OF EDUCATION AND TRAINING HOCHIMINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FINAL REPORT STUDENT’S SCIENTIFIC RESEARCH TOPIC RESEARCH, DESIGN AND IMPLEMENTATION OF A COCONUT SHELL SHREDDER AND DEHYDRATOR MACHINE FOR ORGANIC FERTILIZER PRODUCTION TOPIC NUMBER : SV2022-200 Science group : Engineering Student: Ethics: Faculty: Major: Chu Huy Hoang Men, Women: Men Kinh Faculty for High Quality Training Year: 04 /Training year: 04 Machine Manufacturing Technology Instructor : Phan Thanh Vu, ME Ho Chi Minh city, October,2022 Disclaimer Project title: RESEARCH, DESIGN AND IMPLEMENTATION OF A COCONUT SHELL SHREDDER AND DEHYDRATOR MACHINE FOR ORGANIC FERTILIZER PRODUCTION Advisor: PHAN THANH VU, ME Student: CHU HUY HOANG – Student ID: 18143010 Student: DANG NGOC THIEN – Student ID: 18143045 Student: HOANG HUU NGHIA – Student ID: 18143031  Chu Huy Hoang (Project Leader) - Phone: 0334833907 - Email: 18143010@student.hcmute.edu.vn  Dang Ngoc Thien - Phone: 0923055055 - Email: 18143045@student.hcmute.edu.vn  Hoang Huu Nghia - Phone: 0964966692 - Email: 18143031@student.hcmute.edu.vn Disclaimer: “We declare that the report’s content are the outcome of our research and implementation process Nothing was copied without the source being cited in the reference section We take full responsibility if there is a copyright violation in our report.” Acknowledgements Throughout the period of our capstone project, our group had received a considerable of passionate help and support, which has instructed and motivated us to overcome all obstacles and successfully finished this project Firstly, we would like to take this opportunity to thank the Ho Chi Minh University of Technology and Education, as well as Faculty for High Quality training for creating ideal condition for us to finish the project Secondly, we would like to express our gratitude to Advisor Phan Thanh Vu, ME, who provided our group with valuable instruction and advise that support us in completing our graduation project We resolve problems that arose during the project as a result of these recommendations, as well as learn more about machine design and implementationrelated stuff Thirdly, we appreciate the participate of defense committee: Assoc Prof Truong Nguyen Luan Vu, Dr Phan Cong Binh, Dr, Nguyen Minh Ky, ME Nguyen Van Doan, Mr Huynh Tuan for giving us priceless comments to us Besides, we would like to give credit to Mr Pham Bach Duong, ME, MBA for provide us a handful of experiments and recommendation about our report Mr Truong Thanh Cong, ME – lecturer at Vietnamese-German Center for support us when we using machine tools at here Furthermore, we would like to thank Mr Tien – Director of Khoa Thanh Dat Limited Company for sponsoring us in this project Mr Doanh – Mechanical Machinist at Tuan Nam Precision for helping us in machine assembly and welding We also want to express our gratitude to Mr Tuong Hoang – Automation Manager at framas Vietnam Ltd for supporting us about sheet metal design In conclusion, we deeply thank and appreciate to all people who supporting us in this capstone project Best regard Table of Contents CHAPTER INTRODUCTION 1.1 Introduction 1.2 The urgency of the topic 1.3 Objection of the project 1.4 Research method 1.5 Aim, mission and scope of the project 10 1.6 Input data 10 1.4 Expecting output data 12 CHAPTER LITERATURE REVIEW 13 2.1 Shredding mechanism 13 2.2 Transmission system for shredder mechanism 17 2.3 Motor type selection for hammer mill shredder mechanisms 21 2.4 Dehydrator mechanism 23 CHAPTER MECHANICAL DESIGN 25 3.1 Block diagram 25 3.2 Design and calculate the hammer mill mechanism 27 3.3 Design and calculate the press pulley dehydrator mechanism 40 CHAPTER MANUFACTURING PROCESS 55 4.1 Hammer mill mechanism machining process 55 4.1 Hammer mill cover machining process 70 4.1 Machine frames manufacturing 81 4.1 Dehydrator mechanism manufacturing 86 CHAPTER MACHINE ASSEMBLY PROCEDURES 89 5.1 Hammer mill mechanism assembly 89 5.2 Press belt mechanism assembly 93 5.3 Electrical box wiring and assembly 96 CHAPTER EXPERIMENT AND ANALYSIS 99 6.1 Experiment design 99 6.2 Analysis 104 CHAPTER IMPROVEMENT, RESULT AND CONCLUSION 111 7.1 Improvements 111 7.2 Result 112 7.3 Conclusion 113 References 115 List of Figures Fig 1.1 Vietnam coconut production (ICC) Fig 1.2 Structure of coconut fruit Fig 1.3 Mechanical properties of coconut shell Fig 1.4 Coconut shredder machine from MKS and 3A Fig 1.5 Coconut shredder machine from XTmachinery and JF Brazil Fig 1.6 Fresh and dry coconut weight 11 Fig 1.7 Overall size of fresh and dry coconut husks 12 Fig.2.1 Mechanism of shaft shredder 13 Fig.2.2 Double shafts shredder machine 13 Fig 2.3 Rotary blade mechanism by 3A machinery 14 Fig 2.4 Rotary blade mechanism in food industry 14 Fig 2.5 Hammer mill mechanism 15 Fig 2.6 Gear drive mechanism 17 Fig 2.7 Chain drive 18 Fig 2.8 Belt drive 19 Fig 2.9 3-phases motor working principle 21 Fig 2.10 Wire diagram of 1-phase motor 22 Fig 2.11 1-phase induction motor structure 22 Fig 2.12 General structure of a screw press mechanism 23 Fig 2.13 Belt press mechanism applied in industry 24 Fig 3.1 Block diagram of coconut husk shredder and dehydrator machine 26 Fig 3.2 Mechanism diagram of hammer mill 27 Fig 3.3 Force diagram on hammer mill shaft 34 Fig 3.4 Free body diagram of hammer mill shaft 34 Fig 3.5 Force and moment diagram of hammer mill shaft on yOz plane 35 Fig 3.6 Force and moment diagram of hammer mill shaft on xOz plane 36 Fig 3.7 Mechanism diagram of press pulley 40 Fig 3.8 Force diagram on press pulley 45 Fig 3.9 Free body diagram of press pulley 45 Fig 3.10 Force and moment diagram of press shaft on xOz plane 46 Fig 3.11 Force and moment diagram of press shaft on yOz plane 46 Fig 3.12 Force diagram of belt conveyor shaft 50 Fig 3.13 Free body diagram of belt conveyor shaft 50 Fig 3.14 Force and moment diagram of belt conveyor shaft 51 Fig 4.1 Assembly drawing of hammer mill mechanism 55 Fig 4.2 Technical drawing of main shaft 57 Fig 4.3 Main shaft machining on lathe machine at Vietnamese-German Center 59 Fig 4.4 Main shaft machining on milling machine at Vietnamese-German Center 60 Fig 4.5 Main shaft finished 60 Fig 4.6 Technical drawing of hammer mill rod 60 Fig 4.7 Hammer mill shaft machining at Vietnamese-German Center 63 Fig 4.8 Technical drawing of bushes 64 Fig 4.9 Cutting work piece and drilling bushes at Vietnamese-German Center 66 Fig 4.10 Final product of bushes 66 Fig 4.11 Technical drawing of side plate 67 Fig 4.12 Technical drawing of center plate 67 Fig 4.13 Center and Side plates 68 Fig 4.14 Technical drawing of hammer mil 68 Fig 4.15 Hammer mill 69 Fig 4.16 Hammer mill cover 70 Fig 4.17 Upper cover 70 Fig 4.18 Upper cover assembly drawing 72 Fig 4.19 Upper cover final product 73 Fig 4.20 Middle cover technical drawing 73 Fig 4.21 Middle cover technical drawing 75 Fig 4.22 Middle cover assembled 75 Fig 4.23 Lower cover technical drawing 76 Fig 4.24 Lower cover assembly drawing 78 Fig 4.25 Lower cover manufactured 78 Fig 4.26 Screen technical drawing 79 Fig 4.27 Screen cover technical drawing 79 Fig 4.28 Screen manufactured 80 Fig 4.29 Screen cover 80 Fig 4.30 Machine frame technical drawing 81 Fig 4.31 Welding drawing of machine frame 84 Fig 4.32 Frame manufacturing 84 Fig 4.33 Machine frame finished 84 Fig 4.34 Machine frame wheel and take-up mechanism assembled and painted 85 Fig 4.35 Driving shaft technical drawing 85 Fig 4.36 Driven shaft technical drawing 86 Fig 4.37 Roller support plate technical drawing 86 Fig 4.38 Support plate welded onto machine frame 87 Fig 4.39 Assembled rollers on machine 88 Fig 5.1 Machine assembly procedure 89 Fig 5.2 Hammer mill mechanism assembly 89 Fig 5.3 Assembly hammer mills and bushes onto hammer mill shaft and plates 90 Fig 5.4 Assembly last side plate onto the mechanism by screws and washes 90 Fig 5.5 Assembly the lower cover onto machine frame 91 Fig 5.6 Finished assembly of hammer mill mechanism 91 Fig 5.7 Belt drive assembly process 92 Fig 5.8 Belt drive assembly in practice 92 Fig 5.9 Dehydrator mechanism assembly procedure 93 Fig 5.10 Welding support plate 93 Fig 5.11 Assembly bottom pulley 94 Fig 5.12 Assembly front pulley, belt and under pulley 94 Fig 5.13 Assembly top pulley 95 Fig 5.14 Assembly chain drive 95 Fig 5.15 Wiring diagram 96 Fig 5.16 Thermal relay 96 Fig 5.17 Diameter of wire 97 Fig 5.18 Exterior electrical box 97 Fig 5.19 Interior electrical box 97 Fig 5.20 Assembled machine 98 Fig 5.21 Frond and back views of finished machine 98 Fig 5.22 side views of finished machine 98 Fig 6.1 Starting time (s) 104 Fig 6.2 Time required to change the screen (s) 105 Fig 6.3 Maximum size of input material (mm) 105 Fig 6.4 Maximum size of output material (mm) 106 Maximum size of input material (s) (dynamic) Table 6.9 Maximum size of input material (s) Ideal value 200 Marginal Test Measured Result Test value n’’ value n’’ 100 100 OK 120 OK 140 OK 160 OK 180 OK 10 Maximum measured value: 220 Average %: 80% Maximum size of output material (s) (dynamic) Measured value 200 220 240 230 220 Result Measured value 54 49 50 47 56 45 48 52 51 54 Result OK OK FAIL FAIL OK Table 6.10 Maximum size of output material (s) Ideal value 50 Marginal Test Measured Result Test value n’’ value n’’ 60 52 80% 11 45 100% 12 50 100% 13 48 100% 14 53 70% 15 55 50% 16 48 100% 17 57 30% 18 43 100% 19 10 56 40% 20 Average measured value: 50.4 Average %: 80% Maximum weigh of input material per minute 60% 100% 100% 100% 40% 100% 100% 80% 90% 60% Table 6.11 Maximum weight of input material per minute (kg/min) Ideal value 15 Marginal Test value n’’ 10 Average measured value: 11.5 Working noise (Db) (dynamic) Measured value 10 11 Result Test Measured n’’ value 0% 13 0% 14 20% 14 Average %: 56.6% Result 60% 80% 80% Table 6.12 Working noise (Db) Ideal value 100 Marginal Test Measured value n’’ value 110 96 102 107 98 105 Averaged measured value: 103.7 Result Test n’’ 100% 80% 30% 100% 50% 10 Average %: 57% Measured value 109 104 106 107 103 Result 10% 60% 40% 30% 70% 103 6.2 Analysis 6.2.1 Static test analysis Table 6.13 1-time sampling test results and comments Specification name Result % Comment Material 100% Most of the static test meet the tolerances and requirement except “Weight” and Design of body frame 100% “Overall dimension” Design of hammer mill 100% Most of our mechanical component mechanism manufactured on machine tools are Design of dehydrator 100% precise and working well, but others mechanism elements was welded So that we cannot Working mode 100% avoid the displacement between each Drive cover 100% component The weight of this machine Upgrade machine 100% also fall of our expected because there is component some component heavier than normal Weight (grams) 100% Overall dimensions 0% 6.2.2 Dynamic test analysis Starting time (s) (dynamic) Starting time (s) 12 11 10 Time (s) 8 8 7 2 10 11 Number of experiment Fig 6.1 Starting time (s) Comment: The starting time mainly focus on the required time for the main motor (hammer mill motor) to run stable at maximum speed Because we use 1-phase motor, so we need time for the fuse to pulse the energy into motor and run at stable speed Most of time, we will need at least seconds for the machine to properly run and get ready for shredding But in some case there are a problem related to the drive or the electrical, it will take a little bit longer to get stable stage 104 Time required to change the screen (s) (static) Time requred to change the screen 42 45 40 35 34 35 32 31 32 Time (s) 30 25 20 15 10 Number of experiment Fig 6.2 Time required to change the screen (s) Comment: This is the time we need to spent each time we want to change to others type of screen It mostly around 34 seconds But sometime, there are the stuck coconut coir on the machine so it makes longer to take out the screen Maximum size of input material (mm) Maximum size of input material (mm) 250 220 220 200 200 180 Size (mm) 160 140 150 120 100 100 50 0 10 Number of experiment Fig 6.3 Maximum size of input material (mm) Comment: In this experiment, we try our best to put the largest coconut husk onto the machine which still make the machine work properly The largest size is 220mm At experiment and 10, we put 240mm and 230mm coconut husk into the machine but it gets stuck, so the largest size up to now is 220mm 105 Maximum size of output material (s) (dynamic) Maximum size of output material (mm) Size of output material (mm) 60 50 40 30 20 10 10 11 12 13 14 15 16 17 18 19 20 Nuimber of experiment Fig 6.4 Maximum size of output material (mm) Comment: The maximum size of output material data is mostly the length of coconut coir because the coco peat is too small for considering The thickness of coconut coir is much smaller than our screen so it can pass out easy But the length of them is quite longer than our expected So that our machine only bears out 80% of the test required Working noise (Db) (dynamic) Working noise (Db) 109 110 107 106 105 Noise level (dB) 105 107 104 103 102 98 100 96 95 90 85 10 Experiment number Fig 6.5 Working noise (Db) Comment: We run the machine and then using our smartphone to record the value of noise by app Our machine is considerably noisy because we have the lack in dynamic balancing, so our hammer mill mechanism is very noisy By contract to our dehydrator mechanism which is quite and smooth 106 Maximum weigh of input material per minute Maximum weight of input material per minute (kg/min) Weight per minute (kg/min) 16 13 14 12 10 14 14 11 10 2 Number of experiment Fig 6.6 Maximum size of weight of input material per minute (kg/hour) Comment: We try our best to put as much as coconut husk into the machine But due to a lot of factor like the top cover is quite small and for the safety factor, the best we can is 14kg per minute and average about 11.5 kg per minute At first time we try to run the machine with load, went we start to shred couple of coconut husk, the coconut coir gets stuck in our screen too much so that it blocks the outlet of our machine Although the hammer mill mechanism can work perfectly fine but the output material cannot go through to the next stage so we need to have some adjusting with the screen After we adjusting the screen and start to run in second time, the machine has the problem because the belt conveyor is too near the outlet, so that our coconut gets stuck between the hammer mill mechanism cover and belt conveyor At last, our machine can reach up to 14kg of coconut husk per minute Fig 6.7 First load experiment, coconut coir stuck at screen 107 Fig 6.8 Coconut coir get through after fixing the screen Fig 6.9 Coconut coir get stuck dual to the outlet is small at high output material volume Fig 6.10 Coco peat and coconut coir drop out of the belt conveyor 108 Table 6.14 Test criterial Specification name Materials Imp Unit Ideal value list Weight Overall dimension kg mm Design of body frame Design of hammer mill mechanism Design of dehydrator mechanism Starting time Maximum size of input material Maximum size of output material Maximum weigh of output material per minute Time required to change screen Working noise list Part list in Chapter 100% list Part list in Chapter 100% list Part list in Chapter 100% s mm 200 10 100 220 85% 100% mm 50 60 50.4 80% Kg/min 15 10 11.5 56.6% s 30 40 34.3 45% Db 100 110 103.7 57% Working mode list Drive cover list Upgrade machine component Average match list 500 1750 x450 x830 Marginal value 600 ±5 Measured value C45 Structure steel SPC sheet metal 545 1722x535x800 % Match 100% 100% 0% Low suction force 100% Medium suction force High suction force Belt cover 100% Chain cover Chain tensioner 100% 81.6 % 109 Overall, the matching rate is about 80%, not meet our expectancy although the expectancies are set at moderate low level There are two experiments have lowest performance are: “Time required to change screen” and “Maximum weigh of output material” recorded at 45% and 57% respectively For the first one, we have two main reasons that lead to the latency of this task First, our screen takes out position is not a good position which is blocked by our press roller So that it requires more effort to remove the screen Secondly, the coconut coir sometime gets stuck between the screen and the fixture plate and make it harder to put out the screen For the second one The main reason why this not meet our requirements is the design of inlet and outlet of hammer mill mechanism cover The inlet is quite small so that we cannot put too much material onto the machine at one time The screen and the belt conveyor are to close that lead to the output material getting stuck between them The solution for these problems are: Redesign the upper cover, optimize the screen and adjusting the distance between screen and belt conveyor In conclusion, after series of experiments and analysis Our machine although cannot meet our requirement but still a usable machine after some adjustments Fig 6.11 Conclusion graphic about the experiment 110 CHAPTER 7: IMPROVEMENT, RESULT AND CONCLUSION 7.1 Improvements In order to enhance the quality of life, safety and mechanical aspect of our machine My group have several improvements and addition into this machine Drive cover Fig 7.1 Belt drive with cover Fig 7.2 Chain drive with cover The belt and chain cover play an importance role to protecting the operator from the risk of getting injuries by these drive They also prevent the dusks form coco peat and working environment, as well as enchant the aesthetics of the machine 111 Chain tensioner Fig 7.3 Chain tensioner The chain tensioner helps to fix one of our chain drive problem – loosened chain by using small sprocket that freely rotate on the shaft 7.2 Result: After six months of research, design and implementation Our group finally finished our coconut husk shredder and dehydrator machine using hammer mill mechanism and press belt mechanism Our machine capabilities are: - The machine can shred the coconut husk properly regardless the condition - The output material (coco peat and coconut coir) partly meet our requirement - The hammer mill mechanism work effectively - Safety with feeding door mechanism and drive cover - Productivity is about 720 kg/hour Much higher than we expectation Beside the capability, our machine still has a few weakness including: - Hammer mill mechanism create very annoying sound (about 103.7 Db) - The inlet and outlet quite small for higher feed rate of material - The dehydrator mechanism is not that efficiency Table 7.1 Machine specification Specification Unit Value Hammer mill motor kW Number of hammers Pieces 32 Dehydrator motor kW 0.75 Power grid V 220 Productivity kg/hours 720 Overall dimension mm 1722x535x800 Machine weigh kg ~650 kg 112 7.3 Conclusion Overall, our machine was finished with fully functioned hammer mill mechanism and press belt mechanism The machine generally reaching 80% of our expectation Although the productivity is not meet our requirement, but this still considerable high compared to the same machine on the market For example, the same machine from MKS company limited, with same motor power at 4kw, but they productivity is about two or three husks per minute while these price is about 80 million VND Compared to our machine with take about 35 million VND while productivity is 11.5 kg per minute Just about 1/2 the price but the efficiency is much higher Although our machine aesthetics, dynamic balancing and others mechanical stuff are weaker than MKS After the capstone project, this machine will be transferred to Khoa Thanh Dat company limited at D555A , Long Binh Ward, Bien Hoa city, Dong Nai province as technology transfer Despite the fact that we try our best in both design and implementation, but the lack of time and the financial problem as well as our self that make our machine have few disadvantages First, we cannot afford the polyester belt conveyor which would take about million VND, so that we using textile belt instead That lead to our dehydrator mechanism work not that well although they can squeeze the water on the mix of output material The next problem is our inlet and outlet are not that optimized design, so we cannot put too much material onto the machine at once which decrease our productivity The last thing is our first screen design is not that good for coconut coir, the coir getting stuck frequently between the holes of screen so that we need to change to different design which is sacrifice the output material quality After the machine finished, we also try our best to improving our machine We already add drive cover for belt drive and chain drive as well as assembly the chain tensioner for better and stable chain drive To make it easier for transporting, we added four high quality wheels as well as take-up mechanism when the machine working We also fixed the inlet of upper cover for the safety For the future improvement, we want to adding some feature and improving our existed machine including: - Dynamics balancing our hammer mill mechanism - Changing the textile belt into polyester belt or chain link belt - Redesign and implement the cover for hammer mill mechanism - Adding belt conveyor system to providing material onto the machine automatically - Design and implement the auto packing system for the coconut and coco peat - Adding the inverter on both motor so that our machine can work at 3-phase grid 113 114 References [1] Trinh Chat, Le Van Uyen “Tính tốn thiết kế hệ dẫn động khí” Vietnam Education Publishing House, 2012 [2] Nguyen Ngoc Dao, Tran The Sang, Ho 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