compost bag
August 23, 2018
Bioplastics and biodegradable plastics are new environmentally friendly materials. "Biodegradable" and "compostable" are terms that people often refer to when talking about these materials. They are similar but different.
Biodegradable plastics are plastics that can be completely digested by microorganisms as food for energy. When we think of something that is biodegradable, most people are likely to think that such things will be automatically buried in the garbage disposal plant or in compost, exposed to the sun or dumped in water. The decomposition eventually disappeared without a trace. In fact, biodegradable plastics require a certain amount of time to complete their decomposition process under the action of microorganisms (bacteria and fungi), although there are no specific regulations and requirements for the speed of their decomposition.
Biodegradable plastics are often added with 5% cornstarch or vegetable oil, but according to the US Energy Information Administration (EIA), starch or oil additives have a certain impact on the quality of recycled plastics, so biodegradable plastics and Can not be recycled.
In addition to being biodegradable by microorganisms, a plastic called "compostable plastic" must also meet a time requirement. For example, some standards state that these materials should biodegrade within 180 days in an industrial composting environment. A plastic that is considered compostable means that the material is biodegradable in the composting system (eventually decomposed into carbon dioxide, water, and biomass) and disintegrated (no clearly distinguishable residue) and no toxicity.
Bags made of compostable plastic can only be degraded in an industrial scale composting plant, but not in a home composting box, and they cannot be recycled together with ordinary plastic bags because they contaminate the waste material.
The only difference between biodegradable plastics and compostable plastics is that the former is eaten by bacteria, and the latter needs reprocessing? Of course not entirely, because bags made of biodegradable plastics also need to be disassembled in the equipment. The American Chemical Industry Association (ACC) pointed out that both biodegradable materials and compostable materials require the use of large-scale composting devices for decomposition, and apparently most people do not understand this.
In addition, bioplastics refers to plastics produced from biomass as raw materials. Raw materials include castor oil, soybean oil, or corn starch, some of which are biodegradable, while others are not biodegradable.
Landfill and biodegradation "Only landfills, whether plastic bags or those that can be highly biodegradable, such as paper and intact agricultural products, cannot be biodegraded," one professional pointed out. The Canadian Environment and Plastics Industry Association (EPIC) believes that at present, bio-decomposition will not help solve any existing problems with landfilling legislation. According to them, the solid waste that normally enters landfills has a humidity of about 25% to 30%. However, if it is to be biodegraded, the humidity must reach a level of 65%. Modern landfills basically directly bury ash, blocking air, water, or sunlight. This is why newspapers that were dug up from the rubbish dump 20 years ago can still read. So for the biodegradable polymer market to succeed, it's important to invent a device that can effectively compost.
The idea of turning a traditional food bag into a biodegradable bag has changed its value proposition to whether organic recycling can be used, not just a bag problem. In North America and Europe, biodegradable bags are currently being used as organic garbage collection bags, can liners and garden garbage bags. Basically, these bags are always found in places where food waste collection or organic recycling programs are carried out.
The value of biodegradable food bags is closely related to collection and reuse. In some residential areas, biodegradable bags can be used for secondary use at home, for example, as an organic waste bag and treated together with organic waste. This reuse has been recognized by industry insiders who believe that these bags are biodegraded during the composting process, which means that no bags will be required for landfill disposal.
Challenges and Opportunities Overall, the cost of biodegradable or compostable bags is 3-6 times that of conventional bags. The raw material needed to produce a genuine compostable plastic bag (ie, biodegradable during composting) will be 2 to 3 times more than the polyethylene (PE) material. The California Food Merchants Association objected to San Francisco’s ban on plastic bags for food. Their data shows that the cost of a standard plastic bag is about 2 cents, and that of a bag is 5-8 cents, and the cost of a biodegradable bag. Up to 15 cents. The high price is only one of the major problems facing the biodegradable polymer industry.
Despite this, possible government legislation and expected increases in landfill prices (although these two items are unlikely to occur in the next five years) and the search for alternatives to petroleum products have greatly boosted the world's biodegradable plastics industry. The European Bioplastics Industry Group predicts that global bioplastic production (including biodegradable and non-biodegradable materials) will triple in 2011 to 3 billion pounds (1.36 million tons). The U.S. market research company predicts that the demand for biodegradable plastics in the United States is growing rapidly at an average annual rate of 17%. By 2010, it will reach 507 million pounds, with a total value of 610 million U.S. dollars. A recently released market report shows that in 2007, the global market for biodegradable polymers reached 541 million pounds, which is expected to grow to 1.203 billion pounds in 2012, an average annual compound growth rate of 17.3%. Compostable bags accounted for the largest share of the market, with nearly 242 million pounds in 2007. The sector is expected to reach 586 million pounds in 2012, with a compound annual growth rate of 19.4%.
