Burners flame types

All variations of the previous paragraph are reasons for careful attention to (a) zoning for temperature uniformity control (this chapter) and (b) burner locations, burner flame types, and furnace flow patterns (chap. 7). (See fig. 6.8 showing soak temperature variations between three and five lengthwise zones at minimum firing rates (top set of curves) and at moderate firing rates ([bottom set of curves]). 

Laminar Versus Turbulent Flames. Premixed and diffusion flames can be either laminar or turbulent gaseous flames. Laminar flames are those in which the gas flow is well behaved in the sense that the flow is unchanging in time at a given point (steady) and smooth without sudden disturbances. Laminar flow is often associated with slow flow from small diameter tubular burners. Turbulent flames are associated with highly time dependent flow patterns, often random, and are often associated with high velocity flows from large diameter tubular burners. Either type of flow—laminar or turbulent—can occur with both premixed and diffusion flames. 

Acid sludge Cone and flat-flame type burners, steam-atomized 10-15... 

Conceptually, there are two types of flame spread tests. The length of the specimen is generally much greater than the width and flame propagation is measured in the direction of the longest dimension. In the first type of flame spread tests, the specimen is exposed to a gas burner flame at one end. In the second type, the specimen is exposed to a radiant panel producing a heat flux that varies from one end of the specimen to the other. A pilot flame is used to ignite the specimen at the hot end. An example of each of the two types is described as follows. 

The tool used to produce flames suitable for working glass tubes is variously named torch, burner, blowpipe, lamp, cannon, fire and gun. In the interests of simplicity that used for bench work will be referred to as a bench burner or a burner that used in the hand will be called a handlamp or a lamp. The multiple flame type of burner is used in some workshops for bench work and is universally used for working glass in a glassblower s lathe they will be referred to as crossfires and are shown in Plate 4.5. 

The ammonia gas is detected either by noting its characteristic odor or by observing a piece of wet red litmus paper turning blue when placed above (not in contact with) the solution. To confirm the presence of Na and ions, we usually use a flame test, as follows A piece of platinum wire (chosen because platinum is inert) is moistened with the solution and is then held over a Bunsen burner flame. Each type of metal ion gives a characteristic color when heated in this manner. For example, the color emitted by Na ions is yellow, that of ions is violet, and that of Cu ions is green (Figure 16.11). 

A number of instrumental parameters will affect precision and sensitivity in these atomization techniques. In both systems, bandpass (slitwidth) and lamp current must be optimized. In flame AAS, the other operating parameters are burner height,burner alignment, fuel flow, flame, type, and... 

Fig. 3.14. Heat treating furnace with radiant U-tubes on the roof and back wall. The return legs (2nd and 4th from the hearth) are less radiant than the burner legs (1 st and 3rd from the hearth). Tumbling around the bends completes gas-air mixing so the renewed delayed-mixing flame (type F, fig. 6.2) causes a glow in the second leg. Courtesy of Rolled Alloys, Temperance, Ml.

Rg. 3.15. Evolution of gas-fired radiant tube flames, a = premix flame, open burner, b = nozzle-mix flame, sealed-in burner, c = long, laminar, delayed-mix flame (type F) sealed-in. d = partial premix, followed by long, laminar, delayed-mix flame, sealed-in. 

Fig. 4.16. Modern skelp-heating furnace with heat recovery by load preheating. Some furnaces use type H high-velocity impinging burners others use refractory radiating burners similar to type E, but with concave refractory tiles. (See fig. 6.2 for these flame types.)...

The sawtoothed roof furnaces sometimes had several zones practically im-fired, but they at least had some firing even with reversed gas flow. Furnaces side fired, or roof fired with flat-flame (type E) burners had burners all along the walls or roof. Sawtoothed roof furnaces may have cost less, but with large loads and one fixed baffle, control was difficult. Regardless, a move to sawtooth roofs proceeded because of less cost. 

If the furnace is fired only with conventional (type A) burners or with long-flame (type F or G) burners (fig. 6.2), in its outer wall, the recommended positioning usually puts loads where they can benefit most from the radiation and convection characteristics of those flames. This combination plus two more baffles (to control gas movement and allow effective furnace pressure control, and reinstating the firing of zone 1 almost to the charge door) raised the furnace capacity (figure 6.7). 

For the tests in BS 5438 1976, a test chamber with a minimum volume of 4 m and of 2 m minimum height, easily viewed from the outside, is necessary. The specimen (an assembly of two or more loose layers) is fastened vertically on a test frame with horizontal pins and then ignited by a 45 mm long horizontal-tube burner flame of butane, 45 mm above its lower edge. Specimens for the different types of tests (Test 7, Test 2, Test 3) are characterized in Table 3.37. 

Optimize syngas burner flames for different types of glass productions... 

Boiler trimming methodology varies by boiler manufacturer, fuel type, and control scheme regulating injected air, fuel, or both. However, in any scheme, it is critical, for safety and efficiency, to know the amount of oxygen in the process. This optimization is normally based on overall excess oxygen estimation maintaining an adequate local stoichiometry for each burner, adjustment of the flame type (based on an appropriate control of the air inputs and the operation of the mills), and identification of the optimum number of active burners for each operating load. 

Flame-type burners are commonly used, but may have to be replaced with some other heat source to comply with local safety regulations. An automatic device for temperature control is... 

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