Fuel equivalent concept

Equation (4) states that, to quantify the combustion efficiency, the volume fractions of carbon monoxide and the total hydrocarbon (methane equivalents), the mass flow and the stoichiometry of conversion gas, and the volume flows of primary and secondary air need to be measured. The concept of combustion efficiency is a function of emissions, air dilution, and type of fuel. This concept can be applied to any type of continuous combustion system and any type of fuel. 

Three fundamental concepts are discussed in this chapter. The first one is the eoneept of converting all energy back to fuel equivalent. This concept makes aU forms of energy on the same basis, that is, fuel fired or fuel equivalent. The second one is specific net energy, which describes the energy intensity for production. The third concept is guideline energy performance (GEP) as the best alternative for comparison with actual performance. 

Both enthalpy and work-based steam pricing methods rely on thermodynamic laws as the basis. Cooper (1989) argued that the steam pricing should reflect economic reality. Since the operating cost for a steam system mainly consists of fuel burned for steam generation. Cooper (1989) proposed to use the concept of fuel equivalent (FE) as the basis for steam pricing. In this method, the ratio of FE for steam at different pressures is used to derive the steam prices in placement of the ratios of enthalpy and availability. 

The numerical parameters for each concept are summarized in Table 3.3. The inlet pressure was p = 1 bar, the preheat temperature ranged from Tin = 300-800 K. and the total equivalence ratio ( tot. based on the total amount of air) was fuel-lean and varied from 0.1 to 0.5. For the fuel-rich concept in Fig. 3.16A, the equivalence ratios inside the catalytic channel ranged from 1.0 to 5.0, while Tin was the same for both reacting and bypass air flows. Two total inflow velocities L/in were considered, 10 and 20 mZs. In the CST and i-CST concepts (Figs. 3.3 and 3.16B), the total Uin was the... 

The diesel engine operates, inherently by its concept, at variable fuel-air ratio. One easily sees that it is not possible to attain the stoichiometric ratio because the fuel never diffuses in an ideal manner into the air for an average equivalence ratio of 1.00, the combustion chamber will contain zones that are too rich leading to incomplete combustion accompanied by smoke and soot formation. Finally, at full load, the overall equivalence ratio... 

Two emerging trends endorse the concept of heat-integrated processes first, the production of basic chemicals is moved close to oil and gas wells where crude oil or natural gas is processed in large stand-alone units [1]. Second, fuel cell systems require on-site and on-demand hydrogen production from primary fuels (i.e., natural gas, liquid hydrocarbons or alcohols) [2]. Net heat generation in these processes is equivalent to raw material and energy loss, and is therefore undesirable. 

At the 2000 Detroit Auto Show, GM showed a fuel cell version of its Precept concept car, introduced earlier as a hybrid. The car wasn t functional, but GM vice chairman Harry Pearce said it would be by the end of the year. With a 75-kilowatt-continuous, 105-kilowatt-peak PEM fuel cell and a secret lightweight hydride, the Precept was said to have a range of 500 miles and fuel economy equivalent to 108 miles per gallon of gasoline. Pearce called it simply a step on the long journey to a very different future that we see for the automobile. ... 

The fuel value of food is an important concept in nutrition science. The fuel value is generally reported in units of nutritional Calories. One nutritional Calorie is equivalent to one kilocalorie (1000 calories). It is also known as the large Calorie (uppercase C). 

The operational ability of an air-breathing, liquid-fueled PDE is dependent on the fuel used. In the authors previous publications, a concept of a dual-fuel PDE has been suggested and substantiated [1-3]. The concept particularly implies the use of two liquid energetic materials conventional JPF and HP. In terms of the critical initiation energy, the gas-phase JPF-air mixtures with 5% and 20% of HP vapor were shown to be equivalent to stoichiometric ethylene-air and hydrogen-air mixtures, respectively [3]. As the dual-fuel, air-breathing PDE [1-... 

In 1983 Dr Mark Dry, working for Sasol, proposed a process scheme for maximum diesel production in 1983 (15). While this scheme - shown in Figure 6 - was conceived for a coal based LTFT plant, it is also applicable when natural gas is selected as feedstock thus replacing the coal gasifiers with natural gas reformers. The major difference relative to most LTFT GTL concepts is the inclusion of an oligomerisation unit for the conversion of the light hydrocarbons to liquid fuels which might lead to some 7% additional distillates production compared to equivalent schemes that exclude this process. 

As it has been mentioned above, increasing the make-up fuel enrichment reduces these demands considerably. It should be also pointed out that the concepts of the core complete equipment, scheme and partial refuelings schedule, as they have been accepted in calculations at the phase of preliminary study, are not optimal. They need further multicriterion optimization by using calculational algorithms in which reactor dimensions are reflected equivalently. It enables to reduce the requirements for fuel elements operation. One such method has been presented in paper [30]. 

Let us start as soon as possible with wide introduction of CCS to reduce CO2 emissions. So far, as fossil fuels are combusted this captured (or an equivalent amount of) CO2 must be sequestrated. It is best in the form of elemental carbon (see later) to avoid any diffusive loss. To keep carbon fluxes as small as possible, basic energy should be provided from solar sources as much as possible (for example, the DESERTEC conception). This solar energy is needed for CO2 capture from air and exhaust gases and for CO2 chemical processing (CCC technology). Hence, a combination of DESERTEC with SONNE (see below) is essential and will even deliver the benefit of providing solar electricity for CO2 processing to sun-belt countries. This approach is the precondition for the stepwise replacement of all fossil fuels by solar fuels. 

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