Article by : Gayathri Geethan
Let us have a look at the steps which have to be followed in industrial bio-degradation process.
Bio-degradation Process and Experiments involved:
Bio-degradation is the breakdown of organic matter by microorganisms, such as bacteria and fungi.In practice, almost all chemical compounds and materials are subject to bio-degradation processes. The significance, however, is in the relative rates of such processes, such as days, weeks, years or centuries. A number of factors determine the rate at which this degradation of organic compounds occurs. Factors include light, water, oxygen and temperature. The degradation rate of many organic compounds is limited by their bio-availability, which is the rate at which a substance is absorbed into a system or made available at the site of physiological activity as compounds must be released into solution before organisms can degrade them.The rate of bio-degradation can be measured in a number of ways. Respirometry tests can be used for aerobic microbes. First one places a solid waste sample in a container with microorganisms and soil, and then aerates the mixture. Over the course of several days, microorganisms digest the sample bit by bit and produce carbon dioxide – the resulting amount of CO2 serves as an indicator of degradation. Biodegradability can also be measured by anaerobic microbes and the amount of methane or alloy that they are able to produce.
It’s important to note factors that affect bio-degradation rates during product testing to ensure that the results produced are accurate and reliable. Several materials will test as being biodegradable under optimal conditions in a lab for approval but these results may not reflect real world outcomes where factors are more variable. For example, a material may have tested as biodegrading at a high rate in the lab may not degrade at a high rate in a landfill because landfills often lack light, water, and microbial activity that are necessary for degradation to occur. Thus, it is very important that there are standards for plastic biodegradable products, which have a large impact on the environment. The development and use of accurate standard test methods can help ensure that all plastics that are being produced and commercialized will actually biodegrade in natural environments.
Do ‘Biodegradable’ Plastic Bags Actually Degrade?
This article is an excerpt of an article was submitted by scientists from the University of Plymouth in the UK. This article is highly commendable as it seemed to be an eye opener for fradulent practice of plastic in the name of biodegradable plastic.
As we know that the world has a plastic bag pollution problem which has become a big threat to organisms on earth. In United States alone, 100 billion are used each year. The European Union goes through another 100 billion bags and these single-use plastics often end up in the environment, where they pose a threat to animals. Rather than decomposing, the standard plastic bags break down into tiny pieces that get consumed by a variety of organisms and make their way up the food chain.
In midst of these clearheaded realities, biodegradable plastic bags have been promoted as a better way to get your groceries and other purchases home from the store. A new study has found that biodegradable bags may not actually degrade all that quickly in the environment. Some, in fact, were still able to carry nearly five pounds of groceries after being exposed to the elements for three years.
The report, published in Environmental Science & Technology, describes an experiment by researchers at the University of Plymouth, who sought to find out how plastcis named as biodegradable behaved in three environments such as soil, sea and in open air over time. It gave them a shocking experience after looking at the result because none of them are degraded. Even few could still hold full bag of shopping which could be used to carry near to six pounds of purchases. This research conducted by Richard Thompson, a marine biologist and he said “We examined the materials and found plastic bags, they simply weren’t reliably degrading in any meaningful time scale in the natural environments”.
As we know , a lot of countries are involved in abating plastic use and bringing in alternatives named bio-degradable plastics but this new introduction rather than reducing the problem, it maintains the severity. This study proved that plastics labelledas biodegradable, like shopping bags will only break down in temperatures of 50 degree centigrade. These plastics are also not buoyant, so they are going to sink and they are not going to be exposed to UV rays. This study further revealed that the environment these bags are placed in determines the efficiency of the degrading process.
It is recommended for industrial composting facility at 50 degree centigrade to 60 degree centigrade with specific conditions of pH, humidity and oxygen facility as natural envioronments not paving way for such degrading to happen. As we know these plasic bags are made from polymers combined with mineral oxidant additives that promote their breakdown into smaller pieces. But these plastics break down only under certain conditons that are hard to find in nature.They could even inadvertently malign the beauty of nature via accumulation of residues.
Recycle Mithra- இது புவி நேசர்களின் சங்கமம் 