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278 Waste Management Practices: Municipal, Hazardous, and Industrial
coals. The higher Cl contents result from the presence of PVC in MSW as well as the presence of Cl in
paper waste from the bleaching process and other Cl-containing materials, for example NaCl.

9.8.4 UTILIZATION OF RDF: PRACTICAL ISSUES
The so-called “densified” or d- RDF is available for use as a fuel immediately after processing, or
mixed with coal in the field (Figure 9.16) and into a loading hopper of a boiler equipped to handle
solid fuels (Figure 9.17). For RDF utilization to be successful, whether burned alone or as a co-fuel
with coal, however, various potential difficulties must be addressed. For example, many coal-burning
plants have experienced problems in handling, storing, and conveying materials; for starters, RDF
is less dense than coal. It has been found that when coal and RDF are mixed and stored for long
periods, the more dense coal tends to sink to the bottom of the mixture. If the mix continues to
remain separated at the boiler hopper, uneven combustion will take place as the RDF is burned first

FIGURE 9.16 Piles of coal and RDF to be mixed in the field prior to shipment to heating plant.

FIGURE 9.17 Truck loading a coal–RDF mixture for combustion at a heating plant.