Compostable Plastic Bags are the Future
With the increase in the world population, and many developing countries having overcrowded cities, the problem of waste disposal has assumed drastically alarming proportions. The landfills are increasingly polluted with non degradable products which tend to have a direct impact not only on the surroundings in the form of air pollution due to burning of waste and seepage of pollutants into the soil and nearby water bodies, but would also exert a devastating effect on the health of the population.
This situation warrants a permanent solution to the problem of waste management. The best way to attain better waste management is the concept of segregation of waste at source. This is achieved by segregating biodegradable, non-biodegradable and reusable things at home. The best way to dispose biodegradable waste such as kitchen and yard trash is through the usage of bags for waste disposal which could easily get composted to reduce the burden on the environment.
A compostable plastic bag is one which is capable of being decomposed under aerobic conditions, with specific control of temperature and humidity such that the material is not visually distinguishable and breaks down into carbon dioxide, water, inorganic compounds and biomass at a rate consistent with known compostable materials (ref: ASTM International D 6002). The usage of compostable bags calls for better management of the environment by ensuring that these bags are plastic free and so are compostable in aerobic environments.
The common paper bags are not only biodegradable but also compostable. These bags could also be recycled in order to reduce the cutting down of trees. Recycled paper is nowadays more popularly used as carry bags as well as small pouches. Certain types of compostable plastics are also deemed compostable if they biodegrade, disintegrate and do not have eco toxicity (wastezerosf, 2010). Some compostable materials are also made from corn or potato starch with added resin to enhance the strength to the material.
Other than the option of recycling, the only sensible way is the usage of compostable bags which through their capacity to degrade would reduce environmental pollution.
When these compostable bags were first introduced, they were not so popular because of their flimsy nature and the tendency to tear even if slightly wet things were added to them. However, nowadays the bags have gained strength with the addition of more durable grades of compostable resins, the temperature at which the bags are sealed and the design of the bags (Oder, 2013). One more important feature of compostable bags is that they do not require any special additions to enable them to be composted.
However, for the composting to take place, micro-organisms play a crucial role. The number of micro-organisms should be decorumed by keeping correct temperature and moisture conditions in the compost pit, such that these active organisms really put effect in quick composting without much odor.
The disadvantage of using polyethylene and polypropylene bags is that they are non biodegradable and they would stay on the planet for greater than one hundred years. This problem is overcome with the use of compostable bags. Another advantage is that any form of kitchen or garden waste when added to polyethylene and polypropylene bags would emit odor when the waste is degrading as these bags do not allow aeration inside them.
On the contrary, compostable bags, being made of materials like corn or potato starch, have the capacity to allow air inside them thus making it possible for the waste to degrade without emitting odor as it allows the release of moisture and gases and reduces unwanted side effects (Oder, 2013)
Compared to paper bags, the compostable bags made of corn or potato starch are a better option as they could be used with much ease due to their lighter weight and the capacity to hold more materials for composting. One more advantage of using compostable bags is their capacity to fit in the trash cans of kitchens in a better manner than paper bags.
Considering the advantages and disadvantages of using compostable bags either made of corn or potato starch, they are made into ready to fit sizes which suit the purpose of being used as kitchen waste bags, readily get composted in the presence of moisture, do not leave residues behind and are strong enough to carry kitchen and yard waste, as they contain binders in the form of resins.
Compostable polymers are renewable the reason behind this because they are made from plant materials which can be grown year upon year indefinitely. These plant stuffs come from agricultural non food crops. Therefore, the consumption of polymers would create a sustainable industry. In addition compostable polymers have the latent to cut carbon emissions and decrease CO2 quantities in the atmosphere: this is because the CO2 released when they degrade can be reabsorbed by crops grown to replace them. This makes them close to carbon neutral (The City of Houston, 2016)
However, the most annoying disadvantage is that they start composting once there is sufficient moisture, which brings in the possibility of the bags starting to disintegrate in the trash cans itself. Also other forms of non degradable waste cannot be added to these compostable bags.
Not only these compostable bags are used for waste disposal but also serve important roles in the food industry as they lend themselves as packaging materials for take-away food and door delivered items. The use of compostable bags in the food industry is guided by government norms and it would vary in each country. Some food services charge the customer for the compostable bags. However, the main advantage is that the use of plastics is reduced thus paving way for reduction in environmental pollution.
Though it is just a beginning for the industry to use compostable bags, it would go a long way in preventing excessive usage of polyethylene and other such bags. Providing subsidy for those industrial sectors using compostable bags should be thought about by the governments. Compostable bags are here to stay replacing polyethylene bags!!!