Vietnam produces biodegradable plastic bags into ... water

In less than 3 years, the bag will decompose into water and carbon dioxide, easily penetrating the soil, bringing nutrients to the plants.

In Vietnam, although there are many types of plastic products, especially plastic bags, which are declared biodegradable, they are actually just biological fracturing processes. The process of biodegradation is different from biodegradation, only the aging and disintegration of plastic circuits without complete decomposition. Consequently, leaving soil and water with plastic debris, which pollutes the soil and water, especially preventing microorganisms from growing, making the soil quickly faded and non-porous.

In addition, the utilization of waste plastic combined with oxo-degradable technology to produce useful products is almost neglected . Waste recycling facilities in some trade villages are mainly spontaneous, lack of planning with outdated equipment and technology, causing environmental pollution and significant impacts on the health of people in the region. around.

From that demand, the Institute of Chemistry under the Vietnam Academy of Science and Technology has implemented a research project on manufacturing waste plastic bags from waste plastic. Topic by PhD. Nguyen Trung Duc is the project leader, which was implemented from 2017-2018 and has recently been accepted for excellence.

Previously, the team successfully synthesized oxidation promotion additives (including salts and metal compounds). This type of filler helps to break down the original structure of the waste plastic, making the carbon bonds weakened.

SJ-45 single screw extrusion blow molding machine of Japan is used in the production of self-disposing garbage bags.(Photo: Institute of Chemistry, Vietnam Academy of Science and Technology).

To produce this type of plastic bag, scientists have carefully studied the properties of HDPE - a common plastic waste in Vietnam when discharged directly into the environment which will be extremely toxic. This plastic is processed, mixed well with the aforementioned additives. Next is the extrusion technology, blowing, pressing, pulling . to form a bag. This bag after use, discharged into the environment can decompose.

Compared to the plastic bags on the market, the biodegradable bags of the research group were more durable, the elasticity increased by 5.06%. To test the decomposition, the team buried the bag sample in a soil garden in Phu Tho, after 12 months the bag decomposed 70-100% by weight. It takes less than 3 years to disintegrate the bag, depending on its thickness.

Dr Nguyen Trung Duc, who led the research, said the bag does not break down into small pieces like other plastic bags, but converts it into water and CO2, easily penetrating the soil, bringing nutrients to the plants. . If soaked in activated sludge and compost media, the digestion time of the bag will be shortened to 7-8 months.

On May 28, 2018, self-destructable garbage bags were issued by the General Department of Environment - Ministry of Natural Resources and Environment on the Certificate of environmentally friendly plastic bags No. 74 / CN-TCMT. The research team also submitted an application for a useful solution for the production of biodegradable plastic resins from waste plastic resins and self-destruct packaging made from biodegradable resins.

Currently, the research team has cooperated with Lac Trung Technology and Trading Services Co., Ltd. (Hanoi) to synchronously produce biodegradable bags from waste plastic with a capacity of 30 kg / hour. Thanks to the application of modern technology, the bags are manufactured in different thicknesses, used to hold rough, heavy items and for daily activities. Compared to conventional plastic bags, biodegradable bags have a higher price.

Snapshot of the sample burial process in the soil, Sample burial site: Huong Lung Commune, Cam Khe, Phu Tho (a): preparation of soil samples and bags, (b): soil and sample into bags, (c): Buried sample bags into the trench; (d): Fill the trench with soil.(Photo: Institute of Chemistry, Vietnam Academy of Science and Technology).

According to scientists' evaluation, the research results have opened up the prospect of utilizing the waste plastic waste which is causing environmental pollution to produce useful products, and at the same time, contributing to the implementation of the production policy. environmentally friendly products, replacing traditional products. On the basis of technology, equipment has been built in the subject, can be applied immediately to produce biodegradable bags for other fields, such as food packaging, medicine packaging .

The research team also petitioned the Vietnam Academy of Science and Technology to allow the implementation of a pilot production project to finalize the product, create models, and choose the time to decompose to suit the items. different purpose of use. At the same time, in order for the product to be effectively applied in life, the State needs a synchronous solution, such as production support; propagandize and support people to access and use biodegradable bags. Because the production cost of biodegradable plastic bags is always higher than normal bags, without the support policy, the product can hardly be widely used among people.