Oxidation furnace radiant tubes

Besides the high temperature corrosion processes (such as oxidation, sulfidation and ash deposition) that occur on the outer wall of furnace radiant tubes, high temperature sulfidation, naphthenic acid corrosion and coking on... 

High temperature oxidation of coking furnaces (furnace radiant tubes work at about 500X)... 

Control of high temperature oxidation of furnace radiant tubes... 

The obtainable NO, emissions depend not only on the burner, but are also affected by the particular application. For instance, in a small radiant tube it is clearly more difficult to obtain an efficient recirculation of flue gases as required by flameless oxidation (Figure 23.17). The lowest NO values down to 1- digit ppm could be reached with burners, for which the combustion chamber had been optimized on purpose for flameless oxidation (combustor). In applications of direct firing in industrial furnaces with air preheating in the range... 

Radiant Tubes. For charges that require a special atmosphere for protection of the stock from oxidation, decarburization, or for other purposes, modern indirect-fired furnaces are built with a gas-tight outer casing surrounding the... 

The operating temperature of the radiant tubes in the irradiation chambers of the atmospheric and vacuum heating furnaces is around 300-400°C. ICr-5Mo is used and shows a relatively low high temperature oxidation rate. Combustion products will adhere onto the tube surfaces to form an ash deposit which can decrease the heat transfer efficiency when the ash is quite thick (Fig. 17.9). 

Our consideration of the laws of radiation starts with the concept of a black body, defined as a solid that emits and absorbs (but does not reflect) radiation of all wavelengflis in certain proportions, the absolute and relative amounts governed by the Stefan-Boltzmann Law, Planck s Law, and Wien s Displacement Law, Even though the ideal black body is a theoretical concept, radiant emission from a hole in an otherwise enclosed heated cavity, such as a tube furnace, and from certain dark substances, such as carbon, oxidized iron, and the metal platinum, approximates the black body emission. 

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