Summary： Since the release of the "plastic restriction order" in 2020, the market for biodegradable plastics has grown rapidly. Under the promotion and publicity of biodegradable plastics, the concept of "degradable" equivalent to "environmental protection" began to be known and accepted by the public.

Since the release of the "plastic restriction order" in 2020, the market for biodegradable plastics has grown rapidly. Under the promotion and publicity of biodegradable plastics, the concept of "degradable" equivalent to "environmental protection" began to be known and accepted by the public.

However, are biodegradable plastics "degradable" in all situations? Are biodegradable plastics suitable for use in any situation? Are biodegradable plastics really "environmentally friendly"? In fact, according to the results of existing research, there are only a few scenarios where the use of biodegradable plastics as an alternative has positive environmental benefits.

Agriculture

A small amount of substitution can greatly improve the environmental leakage problem

Agricultural film is one of the products suitable for the application of biodegradable plastics, which is related to the low recovery rate of agricultural film. If the traditional plastic film is allowed to enter the soil, it will cause the problem of soil compacting and fertility decline. If the biodegradable agricultural film is used to replace the traditional agricultural film, the biodegradable agricultural film can be directly degraded in the soil without recycling. This will not only reduce plastic pollution, but also reduce the labor and cost of waste disposal.

The Tsinghua University team and Sinopec analyzed in the newly released ''Environmental Impact Assessment and Policy Support Research Report on Degradable Plastics'' and pointed out that the use of biodegradable plastics instead of traditional plastic mulch can greatly improve the environmental leakage of plastics. The effect of getting twice the result with half the effort.

 

According to the current use of biodegradable plastics in various scenarios, the amount of biodegradable plastics in agriculture is small. If 35% of biodegradable plastics replace traditional agricultural films by 2023, the amount of biodegradable plastics in agriculture will not exceed 500000 tons, with a total production capacity of nearly 18 million tons in the same year. Such a small amount can make a huge difference. If 35% replacement can be achieved, the improvement rate of environmental leakage will reach 50% by 2023. Even if only 15% replacement is achieved, the improvement rate of the environment can reach 25%.

The study suggests that from the perspective of environmental leakage improvement rate, administrative costs can be invested in agricultural areas where environmental leakage problems are more prominent.

 

In contrast, in the overall substitution scenario of the source of life, even if 100 percent of the traditional plastic products within the policy constraints are replaced by biodegradable plastic products, the amount of biodegradable plastic in this field will reach nearly 4 million tons in 2023. However, a large number of replacement for the improvement rate of environmental leakage is only about 20%.

 

It is calculated that the route of replacing 100 per cent of the source of life requires nearly 20 times the amount of biodegradable plastics to achieve the 25% environmental improvement rate achieved by replacing 15 per cent of the agricultural sector. This means that in life to take biodegradable plastics to replace traditional plastics, first of all, a large number of biodegradable plastics are needed, which is prone to waste; secondly, the improvement rate of environmental leakage is low, and the effect is not considerable; to achieve 100 percent replacement in the field of life requires a lot of manpower and material resources to supervise and manage, and the administrative cost is high.