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Show INTRODUCTION Most industrial operations produce waste products as a result of their production. Additionally, most industrial process are energy intensive requiring large amounts of steam, process heating, etc. Some of these generated waste products may posses heating value allowing them to be used as a fuel source. The utilization of waste products as a fuel source can have dramatic effects on the cost of production. Environmental regulations for N O x , C O , particulates and hazardous materials can also have dramatic effects on the design of combustion equipment. An excellent example of a waste to energy application is the refinery process that produces gasoline, kerosene, and other petroleum products. Crude oil is distilled, cracked, and processed to produce a liquid product with specific distillation characteristics. This process is extremely energy intensive as it essentially involves boiling vast amounts of crude oil. While generating a liquid with a specific distillation range, such as gasoline, light gaseous and heavy liquid wastes are generated. These waste products are called refinery gas and residual oil and posses significant heating value. The refinery industry has long used these waste gaseous and liquid products as fuels to generate the heat required to process the crude oil into the desired petroleum product allowing for economical manufacture of petroleum products. Waste fuels can be gaseous, liquid, solid, or any combination thereof (multi-phase). Special considerations must be made when firing waste fuels. Typically, the heating value and flame temperature of the fuel is evaluated for combustion stability to determine if sustaining fuel must be used. Atomization quality and fuel volatility are important considerations for liquid waste fuels. Conveying of solid fuels and its distribution from the burner into the flame can be a problematic issue. The following table lists several of the more common waste fuels used for energy generation and the special considerations required. Table I: Examples and Considerations for Waste to Energy Fuels Typical Examples Considerations Gaseous Waste Fuels • Refinery Gas • Landfill Gas • Off-Gas • Casing Gas • Vent Gas • Digester Gas • Heating Value (low, med, high Btu) • Composition • Water Content • Particulates & Aerosols • Coke Formation • Available Pressure Liquid Waste Fuels • Raffmate Oil • Heads Fuel • Crankcase Oil • Solvents • Alcohols • Acids • Heating Value • Atomization Characteristics • Volatility • Pollutant Precursors • Ash Composition • Conradson Carbon Solid Waste Fuels • Sander Dust • W o o d Bark/Chips • Foodstuff Biomass • Coke • Dried Paper Sludge • Municipal Solid Waste • Heating Value • Volatility • Water Content • Particle Size • Pollutant Precursors • Fuel Conveying • Ash & Slag 2 |