Fuel preparation

Specific gravity is direcdy related to the bulk density of waste fuels prepared ia a variety of ways. Solid oven-dry (OD) wood, for example, has a typical bulk density of 48.1 kg/m (301b/ft ). In coarse hogged form, eg, <1.9-cm minor dimension, this bulk density declines to about24kg/m (151b/ft ). In pulverized form, at a particle size <0.16 cm, this bulk density declines to 16—19 kg/m (10—12 Ib/ft ). Similar relationships hold for municipal waste, agricultural wastes, and related fuels. 

Also, EPRI is iavestigatiag whole-tree bum power plants that will dry and bum SRWC fuel without requiring tree trimming, wood chipping, or other fuel preparation. The concept iavolves the combustion of tree crops from farms distributed within a 40-km radius of a given plant. 

Another furnace that does not require fuel preparation is the stoker boiler, which was used by New York State Electric Gas Corporation (NYSEG) in its TDE tests. At NYSEG, the stoker boiler, which has a 1649°C (3000°E) flame temperature (as does the cyclone boiler), has routinely blended low quaUty coal, and more recently, wood chips with its standard coal to reduce fuel costs and improve combustion efficiency. In the tire-chip tests, NYSEG burned approximately 1100 t of tire chips (smaller than 5x5 cm) mixed with coal and monitored the emissions. The company determined that the emissions were similar to those from burning coal alone. In a second test-bum of 1900 t of TDE, magnetic separation equipment removed metal from the resulting ash, so that it could be recycled as a winter traction agent for roadways. 

In the case of residual fuel firing for gas turbines it is necessary to provide extensive fuel-preparation plant for... 

The fuel management system includes the various types of fuel preparation and fuel delivery equipment, burners, ignitors, stokers, soot blowers, and ash handling equipment. 

A continuous rubber belt used to transport coal from the coal yard to a fuel preparation and storage area. 

First, discussing the established production methods, the steps in propellant processing are oxidizer preparation, fuel preparation, propellant mixing, cast, and cure. A standard practice in industries handling... 

Nash, A. W., Howes, D. A., Principles of Motor Fuel Preparation and Application, ... 

The energy recovery system selected dictates the extent that solid waste must be prepared. Some systems require nothing more than the removal of massive noncombustibles, such as kitchen appliances from the refuse, while other processes require extensive shredding, air classification, reshredding, and drying, In conjunction with fuel preparation, it is usually worthwhile to reclaim metals and glass for recycling. 

The uranium and thorium ore concentrates received by fuel fabrication plants still contain a variety of impurities, some of which may be quite effective neutron absorbers. Such impurities must be almost completely removed if they are not seriously to impair reactor performance. The thermal neutron capture cross sections of the more important contaminants, along with some typical maximum concentrations acceptable for fuel fabrication, are given in Table 9. The removal of these unwanted elements may be effected either by precipitation and fractional crystallization methods, or by solvent extraction. The former methods have been historically important but have now been superseded by solvent extraction with TBP. The thorium or uranium salts so produced are then of sufficient purity to be accepted for fuel preparation or uranium enrichment. Solvent extraction by TBP also forms the basis of the Purex process for separating uranium and plutonium, and the Thorex process for separating uranium and thorium, in irradiated fuels. These processes and the principles of solvent extraction are described in more detail in Section 65.2.4, but the chemistry of U022+ and Th4+ extraction by TBP is considered here. 

Winkler, W., Lay out principles of the integration of fuel preparation in fuel cell systems, in Proceedings 2ndlFCC (International Fuel Cell Conference), NEDO, Kobe, Japan, 1996, pp. 397 100. 

The aim of this study is to convert as much as the hydrogen in the fuel into hydrogen gas while decreasing CO and CH4 formation. Process parameters of fuel preparation steps have been determined considering the limitations set by the catalysts and hydrocarbons involved. Lower S/C (steam to carbon) ratios favor soot and coke formation, which is not desired in catalytic steam and autothermal reforming processes. A considerably wide S/C ratio range has been selected to see the effect on hydrogen yield and CO formation. 

Figure 6. Product compositions of fuel preparation reactors...

The model combustor used in the present study was a copy of one configuration (Configuration 2C) evaluated under the DOE/NASA Low N0x Heavy Fuel Combustor Concepts Program, and consisted of four component sections fuel preparation, fuel-rich combustion, air quench, and fuel-lean combustion sections (2). All of the test fuel was injected into a rich combustion... 

Smoke emissions increased with hydrogen deficient fuels. Results indicated that the smoke level was primarily sensitive to fuel hydrogen content and fuel preparation technique. Smoke levels also showed sensitivity to fuel viscosity and initial boiling point. A better understanding of these interrelated effects is necessary to more confidently translate these subscale results into definitive design data. 

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