Students make dish shaping machine from areca spathe

Using hydraulic pressing technique with appropriate heating level, a group of students from Da Nang successfully created a dish-forming machine from areca spathe, with a capacity of 60 products per hour.

The product was made by Le Van Tuan, Dang Huu Tai, Mai Xuan Son, Phan Tan Sang, Ho Van Ly , students of the mechanical engineering department, University of Technical Education - University of Danang .

Le Van Tuan, the group leader, said that the group wanted to create natural bowls and plates to replace disposable foam products that affect human health and pollute the environment. Therefore, the selected materials are areca spathe, bamboo shoots, coconut fiber, and leaves that are abundant in nature, with high cellulose content, so when pressed into shape, they have high durability and usability.

During four months, the group of students designed and manufactured the press. The machine is rectangular in shape, made of steel pipes joined together, 1.2 m high, nearly 70 cm wide, and weighs about 150 kg.

The machine has a hydraulic cylinder piston press, a dish mold, controls and a cleaning system. When pressing the button on the control panel, the heating system starts to increase the temperature in the mold to about 120 - 180 degrees Celsius in 60 - 90 seconds. When putting the raw material into the mold, the user presses the button on the control panel to supply power to the hydraulic machine. The piston performs the pressing force stroke to shape the product and then retracts back into the cylinder, ending the process.

Introducing the operating principle of the group's dish making machine from areca leaves. (Video: NVCC).

Before being pressed, the areca spathe is cleaned with high pressure compressed air to blow out dirt, increasing the cleanliness of the material surface. After successfully shaping the dishes, they are cleaned with UV light in the machine's tray. During operation, in case of an emergency, the user will press the button to cut off the power and the parts will stop working.

The group's test shows that in one pressing session, depending on the heating time for different materials, the machine's productivity is different. With areca spathe and bamboo shoots, the pressing time is one minute to produce one product, meaning the machine can produce 60 products per hour. With leaves, the pressing time is about 120 products per hour. For each different material, the temperature will be adjusted appropriately to create the best product quality.

The discs are pressed from areca spathes and leaves such as banana leaves, lotus leaves, and almond leaves by the group. (Photo: NVCC).

After shaping, the dishware products can be used to hold fast foods such as sticky rice, sausages, cakes, mixed fruits, etc. According to Tuan, with ingredients such as areca spathe and bamboo shoots having a cellulose fiber structure with strong bonds, it is completely possible to contain liquid foods without damaging the surface of the dishware. The group does not use any additives or adhesives in the process of shaping the dishware. The reason is that if additives are used during pressing, the heating time at high temperatures will cause chemical reactions that create toxic substances that affect human health when using the product.

"In the coming time, the group will cooperate with chemistry teachers to research natural biological glue products that are friendly to human health to create adhesion and polish products with beautiful designs, quality, and better suit the tastes of users ," Tuan said. The group also aims to improve the mold to create more material shapes and a wider variety of pressed materials. This is the basis for the group to introduce the machine to businesses and farmers producing disposable plastic products.

3D design of the machine. (Photo: NVCC).

Dr. Bui He Thong, Lecturer of Mechanical Engineering, University of Technical Education - University of Da Nang, assessed that the group's products have great potential for practical application in the direction of green economic development. However, he said that the current capacity of the machine is quite low, the mechanical system is not yet fully completed. Therefore, the group needs to study to increase the engine capacity, improve the pressing system and mold to be able to diversify the product types.