2010-05-25_PWETC_AgendaPacket - Laserfiche WebLink

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ttac e - iionl iscussi o e Stu its iea olis Waste Management, Inc (WM) conducted a composition analysis at its Twin Cities Material Recovery Facility (MRF) located in Minneapolis. The study is entitled, Summar~~ -Single-Sort Constituent Test, is dated October 18, 2003, and was provided to the Project Team. Purpose of Study -The report provides summary information resulting from the sorting and analyses performed by WM at their Twin Cities MRF. The purpose for the test was to determine the resulting material constituents resulting from single-sort collection and processing. Methodology -Single stream recyclables loads from fourteen (14) WM trucks from nine (9) different cities were stockpiled for the test on Friday, October 17, 2003. The total stockpile was 74.907 tons. The single stream recycling collection systems utilized the standard WM lidded carts. Recyclables were Loaded into the truck using semi-automated or fully automated collection vehicles. The WM report states they ran the test on Saturday, October 18, 2003 as a single test batch, but using normal operating procedures for their Twin Cities MRF. Processed materials and residuals were collected and weighed to determine make-up. Operations and data collection were witnessed by Mr. Dave Kohorst, Financial Analyst, acting in an accounting role for the tabulation of data. Findings - WM reported that the resulting "Residue Fraction of Processed Materials" from this test as 5.95 percent. The WM Twin Cities MRF is comprised of two sequential processing systems: the "single stream process system" (i.e., screens and sorting stations to recover paper) and "containers process system" to recover glass, cans and plastic products. The residue is derived from unrecoverable materials sorted from both systems, including bulky items, air classifier cyclone "fluff ', unmarketable grit, and other trash. It also included floor sweepings. WM stated that unrecoverable materials were defined as materials not targeted for recycling at the Twin Cities MRF. These materials were comprised largely of plastic bags, bulky items and materials incorrectly placed in the recycling cart rather than the trash container by the resident. The WM study categorized these items as "residue" from plant operations, but should be better termed as "unrecoverable." The WM report provided a separate breakdown of products and process residue from both the single stream process system (i.e., "paper line") and the container process system ("paper line"). Paper products represented 74 percent of the total input and the paper line produced about two percent residue of total input. Container products represented 21 percent of the total input and the container line produced about four percent residue of total input. (Approximations do not add to 100 percent due to Project Team rounding.) Color-mixed, broken glass was defined as a product by the 81605