Uncontrolled production and use of disposable plastic tableware will cause global pollution problems. The use of paper tableware (pulp molded tableware) and degradable plastic tableware is one of the methods to reduce pollution.
First of all, what is paper tableware and degradable plastic tableware? Paper tableware refers to pulp molded tableware materials (mainly plant fibers). Degradable plastic tableware can be divided into photo-degradation, bio-degradation, starch degradation and industrial degradation.
Let's talk about the degradation of pulp molded tableware and degradable plastic tableware.
What are the degradation conditions for degradable plastic tableware?
According to manufacturer of degradable plastic, it is only under industrial composting degradation that it is possible to achieve complete degradation the degradable plastic in 6 months.
What are the conditions of industrialized composting?
A specific temperature is required, usually need about 50-60 degrees Celsius, which is not achievable in general soil. In addition, certain humidity, flora and oxygen consumption are needed to reach the conditions of industrial composting. These conditions are can not be achieved in the natural environment.
Source: End-of-life options for bio-plastics. (Image European Bio-plastics)
What happens when degradation plastic enter ordinary soil?
Athens Agricultural University in Greece conducted the degradation test of PLA biodegradable plastics with the actual Mediterranean soil in 2010, and only partial physical disintegration and partial fragmentation were carried out in 11 months. Central South University of forestry science and technology conducted a 12 month PLA plastic degradation test on simulated natural soil in 2014, and its mass loss was only 0.23% after 12 months which is almost no degradation.
What happens when you enter the ocean?
There are have 400 day experiment at Miloit University in Germany that put the biodegradable plastics can be degraded by industrial composting in to seawater and fresh water to test the degree of degradation in 2017. At the result, there are only about 0.5% mass loss of biodegradable plastics. Therefore, degradable plastic tableware can not be degraded naturally in the ordinary environment, only can be degraded in a specific environment.
What is the degradation conditions of pulp molding tableware?
The degradation condition of pulp molding can be degraded as long as the pulp molding tableware is buried in ordinary soil. Because the pulp molded tableware is made of pure natural plants and pulp fiber as raw materials (such as straw, wood, bamboo, reed,etc). Therefore, pulp molding tableware can be 100% degraded in natural environment, and its impact on the environment is lower than that of degradable plastic tableware.
Here are some images for experiments of degradation pulp molding tableware.
Degradation in 20 days (source:Huagong Huanyuan,2020/11/05)
Degradation in 60 days (source:Huagong Huanyuan,2020/11/05)
Advantages of pulp molded tableware
- The raw materials are waste pulp or renewable straw fibers such as wheat, reed, rice straw, bamboo, sugarcane and palm. They come from a wide range of sources and are cheap.
- No waste water is produced and discharged in the production process. Environmentally friendly.
- The product can be fully degraded in natural state within 45-90 days and can be composted at home. After degradation, the main component is organic matter and will not produce any waste residue and pollution.
