Combustion compounds

Catalytic combustion is a process in which a combustible compound and oxygen react on the surface of a catalyst, leading to complete oxidation of the compound. This process takes place without a flame and at much lower temperatures than those associated with conventional flame combustion. Due partly to the lower operating temperature, catalytic combustion produces lower emissions of nitrogen oxides (NOx) than conventional combustion. Catalytic combustion is now widely used to remove pollutants from... 

General Incineration (oxidation) is the best-known method for the removal of gaseous industrial waste. Combustible compounds containing carbon, hydrogen, and oxygen are converted to carbon dioxide and water by the overall exothermic reactions [Eq. (13.72)]. When chlorinated or sulfur-containing compounds are present in the effluent, the products of combustion include HCl/CE or S02/S03. ... 

Table 4.3 lists some upper and lower flammability limits (in air) taken from Refs. [24] and [25] for some typical combustible compounds. Data for other fuels are given in Appendix F. 

One important thermal degradation mechanism of cellulose fibres (cotton, rayon, linen, etc.) is the formation of the small depolymerisation product levoglucosan (Fig. 8.7). Levoglucosan and its volatile pyrolysis products are extremely flammable materials and are the main contributors to cellulose combustion. Compounds that are able to hinder levoglucosan formation are expected to function as flame retardants for cellulose. The crosslinking and the single type of esterification of... 

It is worth pointing out some differences between complete catalytic oxidation for abatement of hydrocarbon emissions and catalytic fuel combustion for the generation of heat and electric power. The most important difference is the operating temperature, which is between 1(X) and 5(X) C for catalytic oxidation and between 300 and 1(KX)-1400°C for catalytic fuel combustion. The other main difference is the concentration of the combustible compound. In catalytic oxidation, trace amounts of hydrocarbons may be removed, which... 

The rate at which a combustible compound is oxidized is greatly affected by temperature. The higher the temperature, the faster the oxidation reaetion will proceed. The chemical reactions involved in the combination of a fuel and oxygen can occur even at room temperature, but very slowly. For this reason, a pile of oily rags can be a fire hazard. Small amounts of heat are liberated by the slow oxidation of the oils. This, in turn, raises the temperature of the rags and increases the oxidation rate, liberating more heat. Eventually, a full-fledged fire can break out. For... 

Combustion is an intensive oxidation reaction of combustible compounds, resulting in high temperatures, heat release, and strong radiation. As discussed in Chapter 1,... 

Ei ure 4.12 Combustion analysis of a hydrocarbon. If a compound containing C and H is burned in oxygen, CO2 and H2O are formed, and the mass of each can be determined. The H2O is absorbed by magnesium perchlorate, and the CO2 is absorbed by finely divided NaOH supported on asbestos. The mass of each absorbent before and after combustion gives the masses of CO2 and H2O. Only a few milligrams of a combustible compound are needed for analysis. 

D. Flammable or Combustible Compounds are any solids, liquids, or gases that ignite easily or bum rapidly. They are classified as compounds with a flash point below 100° F. 

It is obvious that such a mixture as this would form an exceedingly combustible compound but it could not possess any of those marvelous qualities which were attribaced to the Greek Are. It could not bom under water, though some substances, os will presently be explained, have this property. 

Aqueous wastes contain oxidizable compounds within a liquid water stream and may be endothermic or exothermic depending on the concentration of oxidizable compounds. Proper atomization of fhe liquid stream is probably the most critical aspect of handling aqueous wastes. This is because the droplet must be small enough to be capable of completely evaporating within the thermal oxidizer chamber and still allow for sufficient residence time to oxidize the combustible compounds. The fluid nozzle, pressure drop, and atomization fluid (e.g., air or steam) demand (if dual fluid atomization is used) should be matched to what is used in the field to obtain a meaningful simulation. 

ZrOj I Au at 410 °C in the same gas consisting of air with variable concentrations of different combustible compounds [74]. 

Only a few metals unite with hydrogen, and these form gaseous and combustible compounds not yet known in a pure state, but only in a state tof mixture with hydrogen gas. The following metals only are as yet known to combine with hydrogen —zinc, potassium, arsenic, antimony, and tellurium. 

In practice, organic solvents increase the amount of combustion compounds in the flame and, because of that, the ratio between the fuel and oxidant gases must always be optimized when organic solvents are sprayed directly into the flame. The flow rate of the fuel gas and the sample intake may be decreased or the flow of the oxidant increased. 

Tetranitromethane is of explosion whose oxygen balance is 49 % with explosion heat of 1,892 J/g. The pure tetranitromethane is of poor sensitivity that cannot be detonated by even 10 g special as booster. However, it is violently explosive when it is mixed with combustible material at almost zero oxygen balance, and it has a small critical diameter (thickness) and significant detonation and shock sensitivity. Such explosives are generally prepared when they are needed and the quantity addresses the requirement exactly regarding the safety considerations. Table 7.14 lists the detonation properties of tetranitromethane and certain combustible compounds at zero oxygen balance. 

Combustible compound Combustible compound content (%) C(N02>4 content (%) ... 

Fuel gases consist of combustible compounds like hydrocarbons, hydrogen (H2), and carbon monoxide... 

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