Supplemental fuel

The demonstration unit was later transported to the CECOS faciHty at Niagara Falls, New York. In tests performed in 1985, approximately 3400 L of a mixed waste containing 2-chlorophenol [95-57-8] nitrobenzene [98-95-3] and 1,1,2-trichloroethane [79-00-5] were processed over 145 operating hours 2-propanol was used as a supplemental fuel the temperature was maintained at 615 to 635°C. Another 95-h test was conducted on a PCB containing transformer waste. Very high destmction efficiencies were achieved for all compounds studied (17). A later bench-scale study, conducted at Smith Kline and French Laboratories in conjunction with Modar (18), showed that simulated chemical and biological wastes, a fermentation broth, and extreme thermophilic bacteria were all completely destroyed within detection limits. 

In addition to predicting the exhaust composition of both gases and soHds, the abiHty of these chemical equiHbrium programs to do adiabatic calculations makes them useful for computing supplemental fuel requirements and the effect of excess oxidant on temperature. 

StUl another ore preparation is the nodulizing process where the ore is heated in a rotary kiln to incipient fusion. The tumbling action in the kiln causes the phosphate ore to cohere and form spheroidal agglomerates. Combustion of carbon monoxide from the furnaces is used along with supplemental fuel to supply heat to 1300—1500°C. A boring bar is used near the kiln discharge to aid in breaking up the fused ore. The material is then cooled, cmshed, and screened to the appropriate size for furnace feed. 

In 1991, Goodyear began working with Cadence Environmental Energy (Indiana) to market a whole tine feed system to supplement fuel for cement kilns. The system is used by several cement manufacturers. In 1992, Goodyear furnished tines for a Tennessee Valley Authority (TVA) test bum at a Memphis power plant. The electric utiUty used tine-derived fuel (TDE) to supplement coal fuel in a cyclone boiler. These tests were successflil. 

Cement Kilns. The use of scrap tires as a supplemental fuel in cement kilns has had a fairly long history in Germany and Japan, where tires have been used for fuel since the early 1970s. Initially, the scrap tires were purchased by kilns for thek fuel value. As the relative cost of other fuels has... 

The use of scrap tires in industrial faciUties is also a potential growth market. Perhaps the best known user in this category is Archer-Daniels-Midland Company (Decatur, Illinois). Another industrial user, Elexsys (Sauget, Illinois), uses energy derived from its use of IDE as a supplemental fuel to manufacture chemicals used in the mbber industry. 

In 1985, the Emanuel Tire Company in Baltimore processed more than 3 x 10 tires into chips, which are mostly sold to pulp and paper mills as a supplemental fuel the remainder is sold to reclaiming facHities or landfiUed. Only 20% of passenger tires are suitable for recapping. Nonrecappable tires are shredded into 5-cm chips. The Emanuel Tire operation is capable of reducing the 5-cm chips to smaller sizes. Shredded waste tire chips can be granulated into very fine wire and fabric-free mbber particles. 

However, not all the hydrogen that is produeed is used in the produetion of methanol. To prevent an exeessive buildup of hydrogen in the reeireulating methanol synthesis loop, a slipstream is drawn off eonsisting of hydrogen and some CO and CO2. It is fed to the boiler as supplemental fuel to the main natural gas fuel supply. The slipstream is at approximately 800 psi pressure and must be redueed to 75 psi before it ean be fed to the boilers. 

Both of the regenerative oxidizers begin to show high temperature bypass at the 10% LEL loading. This means that the loading point at which the oxidizers would require zero supplemental fuel has been exceeded. Excess heat is now being produced in the oxidizer. This heat must be able to escape from the oxidizer by way... 

Cost. Both capital and operation and maintenance costs, including costs for supplemental fuel, are generally higher than for other disposal alternatives. 

Vessels, e g., waste heat boilers, in which steam is generated incidental to the operation of a processing system containing a number of pressure vessels, such as are used in chemical and petroleum products manufacture. (Equipment which may fire a supplemental fuel should be considered as a fired pressure vessel.)... 

H. W. Frago and R. D. Powell. Re-use of certain oil exploration and production waste as supplemental fuel in the manufacture of cement. In Abstracts Volume, page 151. Annu Aapg-Sepm-Emd-Dpa-Deg Conv (Denver, CO, 6/12-6/15), 1994. 

Methanol contains no sulfur and produces very little nitrogen oxide pollutants when burned, making it a very clean combustion fuel. At a power generating facility, it could be used as a supplemental fuel for gas turbines to meet peak electricity generation requirements, or it could be sold over the fence to commercial fuel and chemical companies. A commercial-scale power facility might generate 200 to 350 MW of electricity, while also producing 150 to 1000 tons per day of methanol. 

Figure 14 Incineration system flow diagram. Waste is incinerated in the presence of air and supplemental fuel the incinerator can be multiple hearth, fluidized bed, liquid injection, rotary kiln, or other types caustic or lime scrubbers are used to remove gaseous pollutants from exhaust gases (from Ref. 11).

Trade-off between oxygen and supplemental fuel source is a direct result of their underlying cost (D13940M, p.l7). 

According to the vendor, HD CatOx, because of its low operating temperature and the integral heat exchanger, minimizes the need for supplemental fuel (D14851Q, p. 3). 

At the Davis-Monthan Air Force Base in Arizona, a full-scale system removed over 700,000 lb of total volatile hydrocarbons (TVH) in a period of 21 months. The average cost was 0.14/lb (D17189V, p. 1). Table 1 displays this cost and the average treatment costs from S.A.V.E. demonstrations at other U.S. Department of Defense (DOD) Air Force Bases. According to the vendor, higher costs represent lower influent total volatile hydrocarbon (TVH) concentrations and increased use of supplemental fuel as a result of decreasing extracted hydrocarbon concentrations (D17146K, p. 1). 

Although tyres can be used as an alternate fuel, they are most often utilized as a supplemental fuel. Tyre fuel exists either in shredded form (known as TDF, or tyre-derived fuel) or as whole tyres. Tyre-derived fuel consists of tyre chips, usually no larger than 5 cm on a side (Blumenthal 1993). The size reduction procedure is itself an energy-intensive process, and costs increase as the particle size decreases (Atal Levendis 1995 Amari et aL 1999). The cost of cryogenic grinding of tyres can be as much as five times higher than that of pulverizing coal (Atal Levendis 1995). Whole tyres or TDF... 

Barlaz, M. A., Eleazer, W. E. Whittle, D. J. 1993. Potential to use waste tires as supplemental fuel in pulp and paper mill boilers, cement kilns and in road pavement. Waste Management and Research, 11, 463-480. 

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