Fuel final products

The Beckstead-Derr-Price model (Fig. 1) considers both the gas-phase and condensed-phase reactions. It assumes heat release from the condensed phase, an oxidizer flame, a primary diffusion flame between the fuel and oxidizer decomposition products, and a final diffusion flame between the fuel decomposition products and the products of the oxidizer flame. Examination of the physical phenomena reveals an irregular surface on top of the unheated bulk of the propellant that consists of the binder undergoing pyrolysis, decomposing oxidizer particles, and an agglomeration of metallic particles. The oxidizer and fuel decomposition products mix and react exothermically in the three-dimensional zone above the surface for a distance that depends on the propellant composition, its microstmcture, and the ambient pressure and gas velocity. If aluminum is present, additional heat is subsequently produced at a comparatively large distance from the surface. Only small aluminum particles ignite and bum close enough to the surface to influence the propellant bum rate. The temperature of the surface is ca 500 to 1000°C compared to ca 300°C for double-base propellants. 

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). 

A modem petroleum refinery is a complex system of chemical and physical operations. The cmde oil is first separated by distillahon into fractions such as gasoline, kerosene, and fuel oil. Some of the distillate fractions are converted to more valuable products by cracking, polymerization, or reforming. The products are treated to remove undesirable components, such as sulfur, and then blended to meet the final product specifications. A detailed analysis of the entire petroleum production process, including emissions and controls, is obviously well beyond the scope of this text. 

The most commonly used fuels for combustion are hydrocarbons, materials that are compounds of only hydrogen and carbon. Occasionally, fuels such as alcohols, that contain oxygen, are burned. Wlieti hydrocarbon fuels with or without oxygen arc burned in air (combusted) to completion, the products are water, from the hydrogen part of the fuel, and carbon dioxide, from the complete conversion of the carbon part. If oxygen is present m the fuel, it shows up in the final product as part of either the water or carbon dioxide. 

Like LNG, the natural gas-to-methanol fuel market relies on stranded gas as feedstock. The advantages of conversion to methanol is that it requires far less specialized infrastructure than LNG since the final product is a 110-octane liquid that ships in regular tanks, and does not need regasification. And because of a plentiful natural gas supply in the... 

The basic approach taken in the analytical studies of composite-propellant combustion represents a modification of the studies of double-base propellants. For composite propellants, it has been assumed that the solid fuel and solid oxidizer decompose at the solid surface to yield gaseous fuel and oxidizing species. These gaseous species then intermix and react in the gas phase to yield the final products of combustion and to establish the flame temperature. Part of the gas-phase heat release is then transferred back to the solid phase to sustain the decomposition processes. The temperature profile is assumed to be similar to the situation associated with double-base combustion, and, in this sense, combustion is identical in the two different types of propellants. 

In the complicated reaction networks involved in fuel decomposition and oxidation, intermediate species indicate the presence of different pathways that may be important under specific combustion conditions. While the final products of hydrocarbon/air or oxygenate/air combustion, commonly water and carbon dioxide, are of increasing importance with respect to combustion efficiency—with the perception of carbon dioxide as a... 

Heat from all the hot exhaust gas streams is used for steam generation to drive the steam turbine. Thus, the final products from the GE fuel-flexible process are pure hydrogen from the first reactor, C02 from the second reactor, and heat for electricity production from the third reactor. A portion of the solids in the chemical loops needs to be purged to avoid ash accumulation and maintain solid reactivity (Rizeq et al., 2002). The overall energy conversion efficiency for the GE fuel-flexible process is estimated to be 60% (Rizeq et al., 2003). 

Selected Properties of the Motor Gasoline and Diesel Fuel Refined from Fe-HTFT Syncrude and Coal Liquids at Sasol 2, Which Were Marketed as Final Products in South Africa in the 1980s... 

The additional and steadily increasing demand for biofuels could lead to a situation where production of biomass derived fuels finally compete with food production. People who can afford cars can pay more for biomass for fuels than people in non-industrialised countries can pay for food production. Fertile soil in non-industrial countries might then be used for energy crops instead of food. This may eventually lead to a situation where only bad soil is left for food crops and the poor, which in addition would eventually also lead to further deforestation of the World s rainforests. 

MTBE is a well known enhancer of the number of octanes in gasoline and as excellent oxygentated fuel additives that decrease carbon monoxide emissions. Therefore, MTBE has been one of the fastest growing chemicals of the past decade. MTBE is produced by reacting methanol with isobutylene from mixed-C4 stream liquid phase over a strong acid ion-exchange resin as catalyst. An excess of methanol is used in order to improve the reaction conversion. This excess has to be separated from the final product. The pervaporation technique, more energy efficient and with lower cost process, has been proposed as alternative to distillation [74],... 

As the electrolyte of a direct methanol fuel cell, acid media is preferable. In alkaline media, carbon dioxide, the final product of menthol oxidation, is adsorbed and accumulated in the electrolyte ... 

Pyrolysis oil (bio-oil) is produced in fast and flash pyrolysis processes and can be used for indirect co-firing for power production in conventional power plants and potentially as a high energy density intermediate for the final production of chemicals and/or transportation fuels. Gas chromatographic analysis of the liqtrid fraction of pyrolysis products from beech wood is given in Table 3.6 (Demirbas, 2007). Biocmde resrrlts from severe hydrothermal upgrading (HTU) of relatively wet biomass and potentially can be used for the production of materials, chemicals,... 

Both fossil fuels and hazardous waste fuels used in Southdown cement kilns contain metals. The raw materials (limestone, clay, sand) used to make cement clinker also contain metals. In fact, certain metals, such as iron and aluminum, are essential components of the final product. While metals cannot be destroyed, the Southdown cement kiln process effectively manages them in the following ways (a) cement kiln operators limit emissions by carefully restricting the metals content in wastes accepted for recycling (b) dust particles containing metals are returned to the kUn through closed-loop mechanisms, where metals are chemically bonded into the cement clinker (c) particles not returned to the kiln are captured in state-of-the-art pollution control devices and (d) small amounts are emitted from the stack in quantities strictly hmited by USEPA s BIF mle. 

The castor plant is widely considered to be a nuisance plant, because it proliferates rapidly in poor, depleted soils that cannot sustain other more important commercial crops. It spreads quickly as a weed, and in some places has been listed as an intrusive species to be eliminated [51, 52]. Nevertheless, in recent years the industrial volume of castor oil has increased dramatically, driven primarily by the global interest in renewable resources for fuel and feedstocks as an alternative to petrochemicals. The majority of the volume growth has come from the Asian continent, primarily from India, where the castor plant is harvested commercially [53]. In addition to its direct use in pol3mrethane products, the oil and its components have been the focus of innovative new derivatization strategies to improve their properties for use in plastics, while retaining high levels of renewable content in the final products. These developments will be described in Section 4.5. 

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