Boiler fuel

The volatiles contents of product chars decreased from ca 25—16% with temperature. Char (lower) heating values, on the other hand, increased from ca 26.75 MJ /kg (11,500 Btu/lb) to 29.5 MJ /kg (12,700 Btu/lb) with temperature. Chars in this range of heating values are suitable for boiler fuel apphcation and the low sulfur content (about equal to that of the starting coal) permits direct combustion. These char products, however, are pyrophoric and require special handling in storage and transportation systems. 

B. K. Schmid and W. C. Bull, "Production of Ashless, Low-Sulfiir Boiler Fuels From Coal," paper presented at ACS Division of Fuel Chem. Symposium on Pollution Control, New York, Sept. 12, 1971. 

The overall yield of the process is at least 87 mol %, and 2.3 mol of methanol per mole of final product are needed, an excess of 15% over the 2.0 theoretical amount. The methanol can be recycled from the manufacture of poly(ethylene terephthalate). Reported utilities consumptions per kilogram of product are 1.2 kg of 1400-kPa steam, 420 kj of boiler fuel, and 0.5 kWh of electricity (72). 

In the SRC work, coal was slurried with a process-derived anthracene oil and heated to 400—455°C at 12.4—13.8 MPa (1800—2000 psi) of hydrogen for 0—1 h. A viscous Hquid was extracted. The product stream contains some hydrocarbon gases, and H2S. The residue is gasified to generate hydrogen for the process. The remaining filtrate is separated into solvent, which is recycled, and SRC, a low ash, tadike boiler fuel. 

Heating value of the product (SRC) is ca 37 MJ/kg (16,000 Btu/lb). Sulfur contents have been reduced from 2—7% initially to 0.9% and possibly less. Ash contents have been reduced from 8—20% to 0.17% (102). These properties permit compliance with EPA requirements for SO2 and particulate emissions. The SRC is primarily intended to be used as a boiler fuel in either a soHd or molten form (heated to ca 315°C). The soHd has a Hardgrove index of 150 (103). Boiler tests have been successfully carried out using a utiHty boiler. 

Solvent Refined Coal Process. Work ia the mid-1960s by the Speacer Chemical Co. (9) and dating the 1970s by the Gulf Chemical Corp. led to two solvent refined coal (SRC) processiag schemes SRC-I for productioa of low ash soHd boiler fuels and SRC-II for distillates, eg, "syn-cmde."... 

Ferguson, B. C.. Monitor Boiler Fuel Density to Control Air/Ftiel Ratio. Hydrocarbon Processing, February 1974. 

Coal competes primarily in the market for low-cost boiler fuels. Coal is also characterized by a relatively low energy content per unit of weight (at best two-thirds chat of residual oil). Consequently, low-cost... 

Tn the early to mid-1980s, retail gas prices began to rise as the more expensive new gas constituted an increasing percentage of the pipelines average cost of gas. This drove consumer prices above the level that would exist in a competitive market, and demand for natural gas was subsequently reduced as large industrial customers switched to other fuels. Also reducing demand were the Fuel Use Act, which prohibited the use of natural gas as a boiler fuel, increased consen a-tion by residential and commercial customers, warnier-than-normal winters, and an economic recession. 

Regional scarcities of coal initially drove these uses. As petroleum became more abundant and as its price fell, oil became more attractive. In firing boilers, fuel oil possessed only a slight advantage over good-quality coal in Btus per unit volume. But liquid fuels were much easier to handle and store than coal. Competitive pressures kept the prices per Btu of residual oil and coal quite close. 

The temperature at which water vapor (steam) condenses. The dewpoint temperature is important in boiler fuel combustion processes, as whenever a metal surface is cooler than flue gas, condensation occurs. If sulfur gases are present and the acid dewpoint (the tem-... 

One of several different types of flue-gas analysis equipment (such as electronic, Fyrite, or Or sat types). They are used to determine boiler fuel combustion efficiency. 

Landfill gas is produced as a result of organic wastes decomposing in landfill sites. It can be recovered at an inexpensive cost of for direct use as a boiler fuel, converted into electricity with a microturbine or upgraded to a higher value fuel gas. This is a very effective mitigation technology since methane is 21 times as powerful as carbon dioxide as a greenhouse gas. 

Low sulfur boiler fuel can potentially be produced from low sulfur western coals with reduced capital investment. 

Similarly, a subbituminous coal (Wyodak-Anderson) which gave only 60% conversion at 427°C in 2 minutes could be converted to >70% at 460°C with no ill effects (see Figure 17). At 470°C there was an indication that conversion had begun to decline at 2 minutes however, this data is extremely limited. The implications of these results with a western subbituminous coal is that a low sulfur boiler fuel may potentially be produced in a single-stage short contact time process. 

Tampella Power Inc. Biomass, coal LHV Fuel for gas turbines, boiler fuel 40 290-334... 

Fuel oil a general term applied to oil used for the production of power or heat. In a more restricted sense, it is applied to any petroleum product that is used as boiler fuel or in industrial furnaces. These oils are... 

The chemistry of a third group of conversion techniques -i.e., partial conversion methods which skim hydrocarbon gases and/or liquids from the coal and leave a char suitable for use as a boiler fuel or gasification feedstock - is. If anything, even more speculative than the chemistry of liquefaction. 

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