Outdoor stockpiles

Stackers with fixed or movable booms (which can be raised and lowered) are used for covered as well as for outdoor blending beds. For reasons of cost it is not a good idea to install permanently mounted belt conveyer systems over outdoor stockpiles. A drawback associated with fixed-boom stackers is that dust nuisance may arise, and the attachment of telescopic discharge spouts or similar devices to... 

Coal can be stored in outdoor stockpiles, in bunkers or in silos. It is usually supplied in the form of "washed smalls" and suitably large discharge cross-sections at bun)cer outlets, etc. should be provided in order to prevent choking, because the coal has poor flow properties. The requisite storage capacity will depend on local conditions and on the rate of fuel consumption of the works. Safety regulations applicable to coal storage must be duly complied with. 

Where environmental conditions permit it, outdoor stockpiling of clinker is an alternative form of storage. In that case, however, precautions to prevent excessive dust formation are necessary. Some possible ways of overcoming dust nuisance more particularly in connection with depositing the clinker on the pile are indicated here. 

In general, any operation involving the suction of air through a flow of material should be avoided, if possible, because this substantially increases the dust content of the exhaust air (classifying effect). When materials are deposited onto an outdoor stockpile, preliminary removal of the finer particles may be advantageous as a means of curbing dust nuisance. 

Outdoor tyre stockpiles also represent a breeding ground for insects and rodents. Rainwater collects in the open space of the impermeable tyres, and, together with trapped windblown pollen and dust, creates an ideal environment for the development of mosquito larvae. The warm, dark recesses of the tyres also provide a supportive environment for rodent habitation. Both rodents and mosquitoes pose a potential threat to human health due to their ability to transmit various diseases (Ohio Air Quality Development Authority 1991). 

The most obvious advantage to using tyres as a fuel source is the partial alleviation of many of the environmental problems associated with traditional disposal of scrap tyres in stockpiles and landfills. The eradication of tyre piles and landfill waste will reduce many of the risks to human health linked to the buildup of tyre waste. The removal of outdoor tyre stockpiles provides great aesthetic benefits as well. 

A large quantity (ca. 1000 Mg) of d-RDF had to be stored and stockpiled for a test burn for periods of ca. 1 year. Storage was outdoors, under cover of plastic sheeting, on a 100 m2 asphalt pad. The pile was originally 2 m high and later increased to 4 m. Moisture evaporated continuously and some condensed on the under surface of the plastic sheeting, forming a "cap" 15 -30 cm thick of wet pellets on the surface of the pile. 

In order to minimise fugitive dust emissions, the following techniques may be employed the covering of skips and vessels the avoidance of outdoor or uncovered stockpiles... 

Fig. 14 Steel tubular structure on outdoor clinker stockpile, at end of belt conveyor (from Funke, 1968)...

Despite restrictions, large amounts of foam furniture, baby products, carpets, plastics, and insulation containing BERs are still sources of exposure in homes and buildings, and must be disposed of after their lifetimes, creating outdoor reservoirs (e.g., landfills, wastewater treatment plants, e-waste recycling facilities, or stockpiles of hazardous wastes) for the future dispersal of PBDEs to the environment (Shaw and Kannan 2009). 

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