Agenda - Council - 11/25/1980 - Laserfiche WebLink

Home

- 17 - The separation programs with the greatest potential waste stream impact are curb-side pickup of recyclables, yard waste composting and mechanical separation of metals. Mandatory programs will have greater potential for recovery but will.require county, city and township elected officials to adopt ordlnances. Centralized yard waste composting systems are readily implement- able but require additional capital for equipment, land and publicity. Aggressive campaigns to increase back yard composting may prove to be the most feasible short-term waste separation strategy. Mechanical separation systems are expected to be developed in conjunction with resource recovery facilities. Because of the fragmented nature of the Region's present solid waste management system, source separation programs will probably ~ ~ .... l~n,~ hv {ndlvidual counties, cities or ~rivate haulers and not on a region-wide basis. Notwithstanding, w~th approprla technical assistance from MPCA and the Metropolitan Council and through implementation of the counties' solid waste master plans, source separation programs can be increased to play a more signifi- cant role in reducing our dependence on landfills. (See Section V regional objectives for source separation goals.) WASTE PROCESSING Waste processing, for purposes of this report, is defined as volume reduction techniques that are employed prior to landfilling, with or without materials recovery systems. SHREDDING Shredding is a solid waste volume reduction technique that con- sists of milling the wastes to reduce waste constituents to smaller, more uniformly sized particles. A shredding operation normally consists of a shredding unit, a ' transport network and the shredfill (landfill accepting shredded wastes). Several types of shredding devices are used, including vertical and horizontal axis hammer mills, vertical axis grinders and horizontal axis impactors. These shredders also usually include a variety of conveyors for waste routing scales, truck loading and .unloading platforms and storage bins or areas. In the shredding process, solid wastes are milled to produce uni- form particle sizes on the order of two to four inches in diam- eter. Waste size reduction results in up to 30 percent greater in-place waste density at the shredfill site. On a site-specific basis, daily cover may not be required, since litter and pathogen problems are reduced. Decreased settlement and improved operation during cold and wet weather have also been noted.