Mixed Plastics in Recycling Programs

A study by the Center for Plastic Recycling Research (CPRR) at Rutgers University analyzed the curbside and drop-off collection of mixed plastics in which the only plastic types specified were heverape bottles. It showed the bottle composition to be roughly 50% PET soda bottles, 30% milk and water bottles and 10-20% non-specified plastic, by weight [Morrow and Metriam, 1989]. The plastic composition from two of the communities (curbside collection in Mt Olive, NJ and drop-off collection in South Plainfield, NJ) is shown in Table 2.4. It provides details on plastics contributed that were not specified for collection in the program. There is a large increase in non-specified plastic collection for the drop-off site study in comparison to the curbside collection study. This illustrates the need for public education and clear, simple collection instructions. 

In 1989 it was estimated that 9 million U.S. households were part of curbside recycling programs attd that 20% collected some type of plastic. Twenty percent of U.S. households ate projected to have ertrbside collection by 1992 with an annual plastics collection of 334 million pounds. In Illinois by the end of 1990,600.000 households were expected to have curbside recycling. It is ctmently estimated tlrat 43 municipalities in Illinois collect some type of plastic, alTecting a total of 221, (XX> residences. Of these, approximately 40% collect some type of mixed pla.stic. None of the curbside programs in Illinois collect LDPE (rims and only a few collect RPC or any type of plastic bottle. 

One of the issues facing PVC recycling is separation of PVC from a stream of mixed plastics. This is particularly important in the United States for PVC packaging, since PVC, where it is collected at all, is generally collected in a program which targets all types of plastic bottles. Several systems have been developed to automatically identify... 

---