Using hydraulic compression technology with appropriate heating levels, a group of students from Da Nang successfully created a machine that molds bowls and plates from bamboo, achieving a production capacity of 60 products per hour.
The product was developed by Le Van Tuan, Dang Huu Tai, Mai Xuan Son, Phan Tan Sang, and Ho Van Ly, students from the Mechanical Engineering Department at Da Nang University of Science and Technology.
Le Van Tuan, the team leader, stated that the group aims to produce natural bowls and plates as alternatives to disposable foam products, which pose health risks and contribute to environmental pollution. Therefore, the chosen materials include bamboo, bamboo shoots, coconut husks, and various types of abundant leaves in nature that have a high cellulose content, ensuring durability and usability when molded.
Over the span of four months, the student team designed and fabricated the pressing machine. The machine has a rectangular shape made of welded steel tubes, measuring 1.2 meters tall, nearly 70 cm wide, and weighing around 150 kg.
The machine includes a hydraulic piston cylinder, a mold for forming bowls and plates, along with control panels and sanitation systems. When the button on the control panel is pressed, the heating system activates, raising the temperature in the mold to approximately 120 – 180 degrees Celsius for 60 – 90 seconds. Once the raw material is placed into the mold, the user presses the button on the control panel to supply power to the hydraulic machine. The piston then moves to exert pressure, forming the product before retracting, completing the process.
Introducing the working principle of the bamboo bowl and plate molding machine developed by the team. (Video: NVCC).
Before molding, the bamboo is cleaned using high-pressure air to blow away dust, enhancing the cleanliness of the material’s surface. After successfully forming the bowls and plates, they are sanitized using ultraviolet (UV) light in the machine’s container. During operation, in case of emergencies, users can press a button to cut power and halt all machine functions.
Testing by the team has shown that the production capacity varies depending on the heating time for different materials during a single pressing cycle. For bamboo and bamboo shoots, one minute of pressing yields one product, meaning the machine can create 60 products per hour. For leaf materials, the hourly output is about 120 products. The temperature will be adjusted based on each material to achieve the best product quality.
Bowls molded from bamboo and leaves such as banana leaf, lotus leaf, and banyan leaf. (Photo: NVCC).
The molded bowls and plates can be used to hold various fast foods such as sticky rice, sausages, cakes, and fruit salad. According to Tuan, with materials like bamboo and bamboo shoots that have a fibrous cellulose structure with strong connections, they can easily hold liquids without damaging the surfaces of the bowls and plates. The team does not use any additives or binders during the molding process. The reason is that using additives at high temperatures during pressing can cause chemical reactions that create harmful substances affecting human health when using the products.
“In the near future, the team plans to collaborate with professors from the Chemistry Department to research natural, health-friendly biological adhesives to enhance the adhesion and finish of the products, making them more aesthetically pleasing and suitable for consumer preferences,” Tuan said. The team also aims to improve the molds to create more diverse shapes and types of pressed materials. This serves as a foundation for the group to introduce the machine to businesses and farmers producing single-use plastic products.
3D design of the machine. (Photo: NVCC).
Dr. Bui Hệ Thống, a lecturer at the Mechanical Engineering Department of Da Nang University of Science and Technology, evaluated the team’s product as having significant potential for practical application in the context of green economic development. However, he noted that the machine’s current capacity is relatively low, and the mechanical system has not yet achieved a high level of refinement. Therefore, the team needs to research increasing the motor power and improving the pressing and mold systems to diversify the types of products produced.
