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Banana as a famous tropical and subtropical fruit, is one of the four most famous fruits in the world, which is a monocotyledon herb belonging to the fruit of the genus Musa (family Musaceae). Banana pseudo stem is the by-product of the planting process. The biomass of banana pseudo stem can reach 27 million tons, which is calculated according to the 2 600 strains per hm2 and pseudo stem's fresh weight of 35 kg per strain. Therefore, banana pseudo stem is a large quantity of agricultural waste of tropical zones in China. The soil nutrients and organic matter can increase soil organic content effectively, and improve soil structure, quality and yield of banana by returning chopped pseudo stem to field in time. The straw shattering and returning technology research are mainly concentrated on wheat straw, corn stover and by-products of other crops in domestic, such as rice and cotton. There are problems such as the excessive consumption of machine power, cutting tool damaged easily due to the winding of stem fiber, which needs further improvement to the machine. In view of the above problems, this paper designed a horizontal-shaft returning chopped machine, which was suitable for the banana pseudo stem that was bulky, brittle and with high moisture content. This paper described the overall design of the machine, and determined the structure parameters and working parameters of main parts, such as pushing device, roll-cutter feeding device and chopped device. The movement and force analysis of chopped blade was also carried out. This machine composed mainly of down device, roll-cutter feeding device, chopped device, leveling device, suspension mechanism and hood. It will by overturn, cut broken feed, crushing returning and leveling four processes to deal directly with banana pseudo. Pushing device mounted on the front of the tractor. Roll-cutter feeding device, chopped device and leveling device connected together in order from front to back on the rear of the tractor. Chopped device located inside the hood, and constitute the grinding chamber with hood. In the course of their work, roll-cutter feeding device and chopped device driven by the power output shaft of the tractor rear, leveling device scrolling rely on friction of between leveling roller and the straw residue on the ground. And this machine can be adapted to different operating environments and operating requirements by adjusting the working height of the suspension mechanism. Field experiments indicated that the chopped percent of banana pseudo stem had reached 96.6% with the 21.4 L/hm2 oil consumption, and the 0.42-0.46 hm2/h efficiency of machine. When the tractor's forward speed reached 2.16-3.60 km/h, the back power shaft output the speed of 720 r/min. The chopped stem's average length of 57 mm had satisfied the agronomic requirements of returning straw. The machine has advantages of excellent performance, simple operation, safe and reliable work, and remarkable ecological and economic benefit, which has a broad prospect for the promotion in the banana planting areas of the south of China. [ABSTRACT FROM AUTHOR]

In recent years, the trend of global warming has become increasingly evident. This grim situation has become a common problem which countries around the world have to face. In addition, with decreasing fossil energy resources, energy shortages have become a major problem to be solved. China is a large agricultural country whose residues of straw, wood and other organic matters are over 900 million tons every year, among which there are more than 300 million tons that can be effectively and easily processed and utilized ( straw occupies about 200 million tons). Biomass resources are extremely rich; once processed into "briquettes", they can replace 200 million tons of ordinary coal. Bio-briquette technology research is of great economic and social importance and plays an invaluable role in easing the global environmental issues and the "energy crisis.". Since the oil crisis in the 1970s, biomass as a kind of clean and renewable energy has attracted the world's attention. China has also conducted a series of research and carried out applications in this field. For now, biomass fuels are the main screw extrusion molding equipment, piston-type and roller die stamping. Roll mode compacted biomass molding machines are most widely used for it has a simple structure, being both compact and easy to use. Flat molding machines are one of the biomass briquetting machines. Flat molding machines applied on the market currently are mostly single pairs of straight rollers, using pulleys and gears for a 2-stage-transmission, and are mainly used with woody biomass, wheat straw, corn stalks, forestry waste and other raw materials. But there is not much research on the use of molding machines for solid fuel made of mixed raw materials such as tropical crop residues, including banana stalks, coconut shell, and sugarcane leaves. In the existing operation processes of die-cutting (flat molding) machines, the vertical rollers (straight press roller) have a more serious abrasion. And in order to achieve a greater transmission ratio, the 2-stage-transmission system applied will make the size of the complete machine too large. To solve the above problems, this paper research designed a tapered roller planetary wheel and an outside molding machine solid fuel level and describes the main components of the aircraft structure. This paper also focuses on the motion analysis and stress analysis of the roll device and determines the optimum value of the key parameter. Performance test results show that: In the case when motor power is 45 kW, cone roll revolution speed is 190 r/min and rotation speed is 543 r/min and the feed conveyor means is 3 kW. The production rate is 850 kg/h, pellet fuel forming rate is 96.5%, particle mass density is 1.25 g/cm3, and the moisture content of the particles after forming is 2.82%, mechanical durability is 96.74%, comply with the requirements of biomass pellet fuel molding. The whole working process with low noise and smooth operation, it has significant economic and ecological benefits and provides a reference for China tropics solid fuel molding machine development and promotion. [ABSTRACT FROM AUTHOR]

Bananas occupy an extremely important position in the world of fruit trade; it is the most important fruit in tropical and subtropical areas. China is one of the world's largest producers of bananas, and bananas have become an agricultural pillar industry in China's subtropical regions. However, the banana stalks are a major agricultural waste. According to the Food and Agriculture Organization (FAO), in 2010, 24 million tons of annual output of waste is banana straw in China. If such a large amount of waste straw is not handled in time, it would seriously pollute the environment and affect the renewal of the banana plantation. Because banana stalks are thick with a high level of moisture and other issues, there are less mature mechanical equipments for banana stalks treatment at the present. There are usually two main types of banana stalk treatment: one is to cut down and pile the stalk in the fields by laborers, and then let it rot; the other one is a centrally smash processing with machines. This kind of machine can achieve a certain crushing effect, but, due to the characteristics of its own design, can't achieve the field operations, and thus brings great inconvenience for the laborers. In view of above situations, according to craft about the banana stalks' crushing and returning in the field, this study designed a feeding type vertical shaft flail extracting machine for banana stalks' crushing and returning, and expounded the machine's overall configuration and the main components of the structure, and determined the key parameters of the optimal value through the analysis of the relationship between components and performance test. The machine could work directly in the field under the tractor traction, for the stalks to achieve down, tackle, grab, feed, crush and return. Field experiments showed that: with the speed for forwarding at 2.16 - 3.60 km/h, for the feed roller at 127.39 r/min, and for the vertical sling knife at 1080 r/min, this machine could achieve a qualification rate of straw smashing of 94.9%, field coverage of 88.61%, stem stubble height of 30 - 35 mm, energy consumption of 4.625 kg/h, and working efficiency of 0.39 hm2/h. This machine was easy to operate and its crushing effect was satisfactory. Its successful implementation could not only greatly improve the production efficiency, and solve the problem of large-scale banana cultivation facing massive stalks processing, but also prevent the pollution of the environment and had important economic and ecological benefits. [ABSTRACT FROM AUTHOR]