TDF AS FUEL IN WASTE WOOD BOILERS AT PULP AND PAPER MILLS

Many mills bum this wood waste in boilers to obtain heat energy for process steam, and to alleviate possible solid waste disposal problems. These waste wood boilers are known as hog-fuel boilers. A base load of supplemental fuel of some kind is required in hog-fuel boilers, because the significant variations of the size, moisture content, and heating value of the wood waste may not allow consistent boiler performance. Supplemental fuel facilitates uniform boiler combustion, and ensures that a minimum amount of power is generated regardless of the fuel value of the wood waste at any one time. 

Operators traditionally use coal, gas, or oil, whichever is the cheapest fuel in their area, as the supplemental fuel. For the past 15 years, however, some paper mills have used TDF commercially or on a test basis in hog-fuel boilers.2 The consistent Btu value and low moisture content of TDF in combination with its low cost in comparison to other supplemental fuels make TDF an especially attractive alternative fuel in this industry. 

The economic value added by the use of TDF varies by location, and, thus, TDF is not universally the most economical fuel for use in pulp and paper mill hog fuel boilers. 

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TDF as Fuel in Waste Wood Boilers at Pulp and Paper Mills... 

TDF as fuel in Waste Wood Boilers at Pulp and Paper Mills. Another plant in this category, Boise-Cascade, was burning ... 

As of the Summer of 1991, at least 10 pulp and paper companies are adding tire-derived-fuel (TDF) to their hog fuel boilers as an alternative supplemental fuel. In addition to boilers at pulp and paper plants, one boiler at a silicon manufacturing facility burns TDF supplementally with their primary fuel of waste wood chips. Information and emissions data from this boiler have been included with this section. Table 5-1 contains a list of pulp and paper mills that have burned TDF commercially, or have tested TDF in the past. 

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