Original by Dr. Steve Wong
August 31,2024
The invention of plastic has undeniably significantly increased crop production. For example, greenhouse films allow many fruits and vegetables to be grown throughout the year, while drip tapes and hoses bring many benefits in irrigating plants like strawberries and vegetables. Farmers can harvest strawberries three times a year in California, and the yield per acre has significantly increased. Mulch film can provide the soil with the right amount of moisture, and hay film and PP twine can store grass for livestock to feed on during the winter.
Global plastic production is about 400 million tons, with agricultural plastics accounting for 4%, which is 16 million tons. The amount that can ultimately be recycled is meager among this large amount of agricultural plastic. The main reason is that waste agricultural films and drip tapes, especially the thinner ones, have very low recycling rates, with only 20% for mulch films. Eventually, due to high costs, they are not recycled. In contrast, thick greenhouse films and drip hose have an 80% recycling rate and are recycled for agricultural plastic or other plastic products.
Plastics that cannot be recycled are either disposed of in landfills by environmental entities or sent to incinerators to produce fuel. In recent years, there have been proposals to recycle them into crude oil chemically, but the feasibility of this approach is doubtful. In some countries, farmers burn waste plastics without supervision, either due to a lack of diligence in collecting and disposing of them or because of high transportation and handling costs. Even in advanced countries like the United States, some farmers burn agricultural waste plastics before dawn, causing permanent harm and damage to the environment and ecology.
I presented the recycling costs of various agricultural wastes compared with the cost of raw materials at the APRC Conference. This indicates that there is a greater financial incentive to use raw materials than recycled materials due to the overproduction of prime materials. Not only is the price of prime-grade materials overwhelming the recycled market, but their chemical properties are also superior to those of recycled materials. Factories might consider using prime-grade materials directly rather than recycled materials. This hinders the recycling rate of agricultural waste. In addition, I proposed to the United Nations Environment Programme that it establish a responsibility system for producers, mandating the use of recycled materials in agricultural production to enhance the recycling of agricultural plastic waste.