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<Municipal Solid Waste Management> Europe 2.3 Topic f: Special wastes Separation of hazardous waste from MSW There is a wide range of practice in the handling of household hazardous waste (HHW) in Europe, and in its separation from MSW. In Northern European countries, like Germany, the Netherlands, and Switzerland, the use of traveling chemocars, vans equipped to collect HHW, is widespread. A typical scheme for collection of HHW, which includes oil, is monthly collection in each neighborhood, with the chemocar standing in a shopping center for a few hours at the end of the route. The overall trend in Europe seems to be to provide a convenient, frequent, and reliable opportunity for separation of HHW. Where there is drop-off of waste or recyclables, it is common to set up permanent acceptance sites for HHW, and most drop-off centers include such facilities. The collection of batteries, sometimes considered to be a part of HHW, is usually handled separately. In many countries in Northern Europe, a purchaser will be asked at the time of battery purchase to turn in the batteries he or she is replacing. In the Netherlands and Germany, glass igloos often include a small container for batteries. Batteries in Europe are recycled for their metals. Also, the use of rechargeables appears to be growing, together with the availability of simple, relatively low-cost rechargers. Construction and demolition debris (C&D) In general, European countries reclaim more construction and demolition waste than other regions. Europe's dense population and old urban infrastructure lend themselves well to intensive recovery. A second factor is the long experience in brick and stone construction. In Northern Europe, the combination of increasing reliance on incineration and the rapidly escalating weight-based landfill tipping fees for non-combustible C&D combine to discourage both waste haulers and contractors from disposing of materials that can be recovered. Furthermore, C&D waste has been the focus of a number of policy initiatives in the last several years, and the concept of producer responsibility is an influence here as well. Increasingly, European construction and demolition sites are served by a multi-container waste removal system, which allows the contractor to source separate recoverable and non-recoverable materials. In regions where this has not yet become accepted practice, waste hauling firms are likely to separate recoverable materials in a separation plant, using some combination of mechanical and manual separation. The most common configuration involves a tipping floor for the materials, which are then partially separated by a loader or bulldozer to remove the oversize or clearly recoverable materials, such as cardboard (generated in large quantities in C&D waste streams). The remaining materials are either pushed into a pit conveyor or loaded in to a hopper conveyor, where they are separated by hand, usually in conjunction with one or more shredding or milling steps. Magnetic separation is also common, especially at the end of the separation process, after size reduction. Where facilities for separation are not available, and economics are favorable (that is, disposal is expensive), limited separation on the tipping floor of transfer stations is not unusual. Recoverable C&D materials in Europe include brick, concrete, stone, wood, and construction-related paper products. Except for wood and paper, most of these materials are crushed in sophisticated stone-crushing plants (similar to those associated with the quarrying of virgin stone), screened to standard sizes, and resold into the market for construction, paving, and other materials. Wood is frequently shredded for mulch, although there is a body of opinion that states that the most environmentally sound disposal strategy for wood, because of its high BTU content, is combustion in a waste-to-energy facility. In deforested, wood-poor countries like Spain, there is a potential for the use of waste wood in domestic cooking and heating. Paper, consisting primarily of kraft paper and corrugated cardboard, is often pulled off the tipping floor, if it is not source-separated, and baled for marketing to traditional paper markets. Recently, there have been some efforts to recover, bale, and market the polyethylene sheeting used in the packaging of construction material pallets, together with the sheeting used to protect curing concrete from rain. Tires Western Europe generates well over 100 million waste tires per year. The European Commission, although giving attention to waste tires, has not yet produced either a recommendation or a directive for its member nations. Although Europeans are suffering from a theoretical tire disposal crisis, the sorts of tire piles sometimes seen in North America are not widely in evidence, except, to some degree, in the UK. Some countries, such as the Netherlands, have extremely high rates of retreading, even of passenger tires, and there is a small amount of reclaiming. Retreading rates of 25-30% are not uncommon in Europe, and in some countries, they are higher. Where reclamation possibilities do not exist, the recognized tire disposal option in Europe is either burning in a waste-to-energy facility or burial, after shredding, in a landfill. European Union laws and regulations continue to restrict these options, due in part to concern over operational and environmental consequences of too many tires in the disposal stream. In some more southern European countries, like Greece, Portugal, and Spain, fewer waste tires are generated, since there are fewer cars, and the tires are used for longer. In the Naples, Italy region, there are a large number of small-scale tire reclamation businesses, including several that re-groove bus and truck tires. Used oil Used oil is considered neither a hazardous waste nor a "normal" solid waste in much of Europe. Many European drop-off centers offer used-oil depots, and some countries have special containers placed near glass igloos and other drop-off facilities. In most countries, certain if not all gas stations and retail outlets take oil back in point-of-purchase collection programs. Waste oil is accepted in most household hazardous waste programs, but waste oil containers are not generally considered hazardous. Improperly disposed of oil is considered so dangerous in densely populated Europe that at least one country, Austria, has prohibited do-it-yourself oil changes to force all used oil to be removed in gas stations, where it can be separately collected and recycled. Medical and hospital waste The overwhelming majority of hospital waste in Western Europe is incinerated, in incinerators meeting stringent air pollution control standards; this is the ideal for Eastern European countries as well. In many Western European nations, air pollution control regulations are forcing a shift from smaller, on-site, hospital-based incinerators to larger, regional medical waste incinerators with acid gas scrubbers and electrostatic precipitators or baghouses. Some governments, like that of Switzerland, have a bias against on-site incineration, as pollution control equipment is seldom affordable at a small scale. Both dedicated regional medical waste incinerators and waste-to-energy plants figure in the disposal of European medical waste. A German innovation co-locates smaller, dedicated medical waste incinerators on the sites of high-tech waste-to-energy facilities, and cycles their waste gases through the pollution control system of the larger installation. In Germany and Sweden, there is in some cases 100% redundancy, meaning that there is a fully capable backup incinerator which can burn all medical wastes. It is not usual for dedicated medical waste incinerators, which are designed in the same manner as hazardous waste incinerators, to recover energy. In rare cases, the older practice of sterilization or autoclaving before landfilling is used as an alternative. Formerly, many hospitals had their own on-site incinerators, and in some places this is still the case, although these smaller incinerators are increasingly being phased out as appropriate regional waste-to-energy capacity becomes available. Sewage sludge Sewage sludge is arguably not a waste stream, but a product of waste processing. Sewage sludge is a product of primary or secondary wastewater treatment, and is usually generated in the form of a moist, cake-like substance whose moisture content varies from 40% to 60% by weight. There are six general options for sludge handling, four of which produce an inter-mediate substance or product, which must be further handled through processing or land application. These are: (a) land application without treatment; (b) neutralization, using lime or other substances; (c) drying; (d) composting or co-composting; (e) incineration; and (f) landfilling and/or use as a cover material in landfill management. Europeans employ all of these methods. When mixed MSW composting was a more important waste processing strategy, the co-composting of sludge with this material was more common, since the moisture content and high nitrogen of the sludge was able to complement and offset the dryness and high carbon content of the paper in the waste stream. The decrease in co-composting, in part due to the implementation of high compost standards, means that more sludge must be handled in other ways. Where incinerators are available, incineration of sludge is deemed helpful in reducing the combustibility of excessively combustible waste streams.
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