Composting plastics and

Narayan R (2001) Drivers for biodegradable/compostable plastics and role of composting in waste management and sustainable agriculture. Bioprocess Solid Waste Sludge 1(1)... 

To meet the requirements of biodegradability under industrial composting conditions (compostable plastics), a plastic must satisfy the primary requirement of complete biodegradability as measured by the microbial conversion of the plastic carbon to CO2 under composting conditions, as discussed in an earlier section. In addition, it has to meet the disintegration and safety criteria to make a claim of compostability. ASTM D6400, ASTM D6868, ISO 17088 and EN 13432 are specification standards for compostable plastics and require ... 

The American standard ASTM 6400 provides standard specifications for compostable plastics and products manufactured from these materials. ASTM 6400, like all other standards, states its scope of validity, defines its concepts, and states the specific requirements (here for compostable materials and/or products). Similar to DIN EN 13432, subsection 6 (Detailed Requirements) describes the chemical tests as well as the general proof of general biodegradability, followed by the test for total disintegration. However, ASTM 6400 provides little detailed information, but rather refers repeatedly to ASTM D6002 regarding test execution. 

Most of the plastics and synthetic polymers that are used worldwide are produced from petrochemicals. Replacing petroleum-based feedstocks with materials derived from renewable resources is an attractive prospect for manufacturers of polymers and plastics, since the production of such polymers does not depend on the limited supply of fossil fuels [16]. Furthermore, synthetic materials are very persistent in the environment long after their intended use, and as a result their total volume in landfills is giving rise to serious waste management problems. In 1992,20% of the volume and 8% of the weight of landfills in the US were plastic materials, while the annual disposal of plastics both in the US and EC has risen to over 10 million tons [17]. Because of the biodegradability of PHAs, they would be mostly composted and as such would be very valuable in reducing the amount of plastic waste. 

PLA is a compostable plastic material. Chemical hydrolysis is considered to be the main degradation route for PLA [14]. This hydrolysis process takes place at high humidity and at elevated temperatures (for example in industrial composting facilities). The fragments that result from the hydrolysis process, i.e., short oligomers and monomers, then can be metabolized by microorganisms. Therefore,... 

BASE sells compostable and bio-based Ecoflex /PLA blends under the trade name Ecovio . Years of experience with biodegradable plastics and the vast compounding know-how of BASE has led to Ecovio , with most optimal mechanical properties and processability that by far exceed the properties of pure dryblends of the compound partners. 

This report uses the American Society for Testing and Materials (ASTM) definitions of biodegradable and compostable plastics. 

For each of the steps in the flow diagram, Figure 1, standards organizations worldwide have developed very similar and entirely appropriate laboratory simulation methods for testing plastics for use in various environments such as compost, soil, water, etc. Developing plastics may, therefore, be tested and approved as environmentally degradable in a particular environment, such as soil, compost, seawater and freshwater. Based on these methods, specifications have been established for what is and what is not disposable in such sites or use environments. 

Remove the plastic and plant your crops, disturbing the soil as little as possible, Solarization will only treat the top 3"-5" of soil, so deeper cultivation may bring up pathogens and seeds that can reinfest the newly treated plot. Since solarizing may also harm the microorganisms that help make soil organic matter available to plants, you may want to top-dress your crops with a microbe-rich material such as finished compost. 

The easiest, neatest way to make compost in a small space is in a ready-made compost bin. Most are made from recycled plastic, but if the bin has to be positioned in view, there are also attractive wooden bins available, which can be painted or stained any color you want. Most come without a base so that they can stand on top of the soil—this allows the microorganisms in the soil and larger composting worms and beetles to move up through the material in the bin, composting as they go. If you do not have access to soil, choose a bin with a base and start off with a layer of soil, adding some more if you can as your heap builds up. 

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